edit.c

Go to the documentation of this file.

/*
 *  Edit control
 *
 *  Copyright  David W. Metcalfe, 1994
 *  Copyright  William Magro, 1995, 1996
 *  Copyright  Frans van Dorsselaer, 1996, 1997
 *  Copyright  Frank Richter, 2005
 *
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 *
 * TODO:
 *   - EDITBALLOONTIP structure
 *   - EM_GETCUEBANNER/Edit_GetCueBannerText
 *   - EM_HIDEBALLOONTIP/Edit_HideBalloonTip
 *   - EM_SETCUEBANNER/Edit_SetCueBannerText
 *   - EM_SHOWBALLOONTIP/Edit_ShowBalloonTip
 *   - EM_GETIMESTATUS, EM_SETIMESTATUS
 *   - EN_ALIGN_LTR_EC
 *   - EN_ALIGN_RTL_EC
 *   - ES_OEMCONVERT
 *
 */

#include "config.h"

#include <stdarg.h>
#include <string.h>
#include <stdlib.h>

#include "windef.h"
#include "winbase.h"
#include "wingdi.h"
#include "winuser.h"
#include "imm.h"
#include "usp10.h"
#include "commctrl.h"
#include "uxtheme.h"
#include "vsstyle.h"
#include "wine/unicode.h"
#include "wine/debug.h"
#include "wine/heap.h"

WINE_DEFAULT_DEBUG_CHANNEL(edit);

#define BUFLIMIT_INITIAL    30000   /* initial buffer size */
#define GROWLENGTH      32  /* buffers granularity in bytes: must be power of 2 */
#define ROUND_TO_GROW(size) (((size) + (GROWLENGTH - 1)) & ~(GROWLENGTH - 1))
#define HSCROLL_FRACTION    3   /* scroll window by 1/3 width */

/*
 *  extra flags for EDITSTATE.flags field
 */
#define EF_MODIFIED     0x0001  /* text has been modified */
#define EF_FOCUSED      0x0002  /* we have input focus */
#define EF_UPDATE       0x0004  /* notify parent of changed state */
#define EF_VSCROLL_TRACK    0x0008  /* don't SetScrollPos() since we are tracking the thumb */
#define EF_HSCROLL_TRACK    0x0010  /* don't SetScrollPos() since we are tracking the thumb */
#define EF_AFTER_WRAP       0x0080  /* the caret is displayed after the last character of a
                       wrapped line, instead of in front of the next character */
#define EF_USE_SOFTBRK      0x0100  /* Enable soft breaks in text. */
#define EF_DIALOGMODE           0x0200  /* Indicates that we are inside a dialog window */

#define ID_CB_LISTBOX 1000

typedef enum
{
    END_0 = 0,          /* line ends with terminating '\0' character */
    END_WRAP,           /* line is wrapped */
    END_HARD,           /* line ends with a hard return '\r\n' */
        END_SOFT,               /* line ends with a soft return '\r\r\n' */
        END_RICH                /* line ends with a single '\n' */
} LINE_END;

typedef struct tagLINEDEF {
    INT length;         /* bruto length of a line in bytes */
    INT net_length;         /* netto length of a line in visible characters */
    LINE_END ending;
    INT width;          /* width of the line in pixels */
    INT index;          /* line index into the buffer */
    SCRIPT_STRING_ANALYSIS ssa; /* Uniscribe Data */
    struct tagLINEDEF *next;
} LINEDEF;

typedef struct
{
    LPWSTR text;            /* the actual contents of the control */
        UINT text_length;               /* cached length of text buffer (in WCHARs) - use get_text_length() to retrieve */
    UINT buffer_size;       /* the size of the buffer in characters */
    UINT buffer_limit;      /* the maximum size to which the buffer may grow in characters */
    HFONT font;         /* NULL means standard system font */
    INT x_offset;           /* scroll offset    for multi lines this is in pixels
                                for single lines it's in characters */
    INT line_height;        /* height of a screen line in pixels */
    INT char_width;         /* average character width in pixels */
    DWORD style;            /* sane version of wnd->dwStyle */
    WORD flags;         /* flags that are not in es->style or wnd->flags (EF_XXX) */
    INT undo_insert_count;      /* number of characters inserted in sequence */
    UINT undo_position;     /* character index of the insertion and deletion */
    LPWSTR undo_text;       /* deleted text */
    UINT undo_buffer_size;      /* size of the deleted text buffer */
    INT selection_start;        /* == selection_end if no selection */
    INT selection_end;      /* == current caret position */
    WCHAR password_char;        /* == 0 if no password char, and for multi line controls */
    INT left_margin;        /* in pixels */
    INT right_margin;       /* in pixels */
    RECT format_rect;
    INT text_width;         /* width of the widest line in pixels for multi line controls
                       and just line width for single line controls */
    INT region_posx;        /* Position of cursor relative to region: */
    INT region_posy;        /* -1: to left, 0: within, 1: to right */
    EDITWORDBREAKPROCW word_break_proc;
    INT line_count;         /* number of lines */
    INT y_offset;           /* scroll offset in number of lines */
    BOOL bCaptureState;         /* flag indicating whether mouse was captured */
    BOOL bEnableState;      /* flag keeping the enable state */
    HWND hwndSelf;          /* the our window handle */
    HWND hwndParent;        /* Handle of parent for sending EN_* messages.
                           Even if parent will change, EN_* messages
                       should be sent to the first parent. */
    HWND hwndListBox;       /* handle of ComboBox's listbox or NULL */
    INT wheelDeltaRemainder;        /* scroll wheel delta left over after scrolling whole lines */
    /*
     *  only for multi line controls
     */
    INT lock_count;         /* amount of re-entries in the EditWndProc */
    INT tabs_count;
    LPINT tabs;
    LINEDEF *first_line_def;    /* linked list of (soft) linebreaks */
    HLOCAL hloc32W;         /* our unicode local memory block */
        HLOCAL hlocapp;                 /* The text buffer handle belongs to the app */
    /*
     * IME Data
     */
    UINT composition_len;   /* length of composition, 0 == no composition */
    int composition_start;  /* the character position for the composition */
    /*
     * Uniscribe Data
     */
    SCRIPT_LOGATTR *logAttr;
    SCRIPT_STRING_ANALYSIS ssa; /* Uniscribe Data for single line controls */
} EDITSTATE;


#define SWAP_UINT32(x,y) do { UINT temp = (UINT)(x); (x) = (UINT)(y); (y) = temp; } while(0)
#define ORDER_UINT(x,y) do { if ((UINT)(y) < (UINT)(x)) SWAP_UINT32((x),(y)); } while(0)

/* used for disabled or read-only edit control */
#define EDIT_NOTIFY_PARENT(es, wNotifyCode) \
    do \
    { /* Notify parent which has created this edit control */ \
        TRACE("notification " #wNotifyCode " sent to hwnd=%p\n", es->hwndParent); \
        SendMessageW(es->hwndParent, WM_COMMAND, \
             MAKEWPARAM(GetWindowLongPtrW((es->hwndSelf),GWLP_ID), wNotifyCode), \
             (LPARAM)(es->hwndSelf)); \
    } while(0)

static LRESULT EDIT_EM_PosFromChar(EDITSTATE *es, INT index, BOOL after_wrap);

/*********************************************************************
 *
 *  EM_CANUNDO
 *
 */
static inline BOOL EDIT_EM_CanUndo(const EDITSTATE *es)
{
    return (es->undo_insert_count || strlenW(es->undo_text));
}


/*********************************************************************
 *
 *  EM_EMPTYUNDOBUFFER
 *
 */
static inline void EDIT_EM_EmptyUndoBuffer(EDITSTATE *es)
{
    es->undo_insert_count = 0;
    *es->undo_text = '\0';
}

static HBRUSH EDIT_NotifyCtlColor(EDITSTATE *es, HDC hdc)
{
    HBRUSH hbrush;
    UINT msg;

    if ((!es->bEnableState || (es->style & ES_READONLY)))
        msg = WM_CTLCOLORSTATIC;
    else
        msg = WM_CTLCOLOREDIT;

    /* Why do we notify to es->hwndParent, and we send this one to GetParent()? */
    hbrush = (HBRUSH)SendMessageW(GetParent(es->hwndSelf), msg, (WPARAM)hdc, (LPARAM)es->hwndSelf);
    if (!hbrush)
        hbrush = (HBRUSH)DefWindowProcW(GetParent(es->hwndSelf), msg, (WPARAM)hdc, (LPARAM)es->hwndSelf);
    return hbrush;
}


static inline UINT get_text_length(EDITSTATE *es)
{
    if(es->text_length == (UINT)-1)
        es->text_length = strlenW(es->text);
    return es->text_length;
}


/*********************************************************************
 *
 *  EDIT_WordBreakProc
 *
 *  Find the beginning of words.
 *  Note:   unlike the specs for a WordBreakProc, this function can
 *      only be called without linebreaks between s[0] up to
 *      s[count - 1].  Remember it is only called
 *      internally, so we can decide this for ourselves.
 *      Additionally we will always be breaking the full string.
 *
 */
static INT EDIT_WordBreakProc(EDITSTATE *es, LPWSTR s, INT index, INT count, INT action)
{
    INT ret = 0;

    TRACE("s=%p, index=%d, count=%d, action=%d\n", s, index, count, action);

    if(!s) return 0;

    if (!es->logAttr)
    {
        SCRIPT_ANALYSIS psa;

        memset(&psa,0,sizeof(SCRIPT_ANALYSIS));
        psa.eScript = SCRIPT_UNDEFINED;

        es->logAttr = heap_alloc(sizeof(SCRIPT_LOGATTR) * get_text_length(es));
        ScriptBreak(es->text, get_text_length(es), &psa, es->logAttr);
    }

    switch (action) {
    case WB_LEFT:
        if (index)
            index--;
        while (index && !es->logAttr[index].fSoftBreak)
            index--;
        ret = index;
        break;
    case WB_RIGHT:
        if (!count)
            break;
        while (index < count && s[index] && !es->logAttr[index].fSoftBreak)
            index++;
        ret = index;
        break;
    case WB_ISDELIMITER:
        ret = es->logAttr[index].fWhiteSpace;
        break;
    default:
        ERR("unknown action code, please report !\n");
        break;
    }
    return ret;
}


/*********************************************************************
 *
 *  EDIT_CallWordBreakProc
 *
 *  Call appropriate WordBreakProc (internal or external).
 *
 *  Note: The "start" argument should always be an index referring
 *      to es->text.  The actual wordbreak proc might be
 *      16 bit, so we can't always pass any 32 bit LPSTR.
 *      Hence we assume that es->text is the buffer that holds
 *      the string under examination (we can decide this for ourselves).
 *
 */
static INT EDIT_CallWordBreakProc(EDITSTATE *es, INT start, INT index, INT count, INT action)
{
    INT ret;

    if (es->word_break_proc)
        ret = es->word_break_proc(es->text + start, index, count, action);
    else
        ret = EDIT_WordBreakProc(es, es->text, index + start, count + start, action) - start;

    return ret;
}

static inline void EDIT_InvalidateUniscribeData_linedef(LINEDEF *line_def)
{
    if (line_def->ssa)
    {
        ScriptStringFree(&line_def->ssa);
        line_def->ssa = NULL;
    }
}

static inline void EDIT_InvalidateUniscribeData(EDITSTATE *es)
{
    LINEDEF *line_def = es->first_line_def;
    while (line_def)
    {
        EDIT_InvalidateUniscribeData_linedef(line_def);
        line_def = line_def->next;
    }
    if (es->ssa)
    {
        ScriptStringFree(&es->ssa);
        es->ssa = NULL;
    }
}

static SCRIPT_STRING_ANALYSIS EDIT_UpdateUniscribeData_linedef(EDITSTATE *es, HDC dc, LINEDEF *line_def)
{
    if (!line_def)
        return NULL;

    if (line_def->net_length && !line_def->ssa)
    {
        int index = line_def->index;
        HFONT old_font = NULL;
        HDC udc = dc;
        SCRIPT_TABDEF tabdef;
        HRESULT hr;

        if (!udc)
            udc = GetDC(es->hwndSelf);
        if (es->font)
            old_font = SelectObject(udc, es->font);

        tabdef.cTabStops = es->tabs_count;
        tabdef.iScale = GdiGetCharDimensions(udc, NULL, NULL);
        tabdef.pTabStops = es->tabs;
        tabdef.iTabOrigin = 0;

        hr = ScriptStringAnalyse(udc, &es->text[index], line_def->net_length,
                                         (1.5*line_def->net_length+16), -1,
                                         SSA_LINK|SSA_FALLBACK|SSA_GLYPHS|SSA_TAB, -1,
                                         NULL, NULL, NULL, &tabdef, NULL, &line_def->ssa);
        if (FAILED(hr))
        {
            WARN("ScriptStringAnalyse failed (%x)\n",hr);
            line_def->ssa = NULL;
        }

        if (es->font)
            SelectObject(udc, old_font);
        if (udc != dc)
            ReleaseDC(es->hwndSelf, udc);
    }

    return line_def->ssa;
}

static SCRIPT_STRING_ANALYSIS EDIT_UpdateUniscribeData(EDITSTATE *es, HDC dc, INT line)
{
    LINEDEF *line_def;

    if (!(es->style & ES_MULTILINE))
    {
        if (!es->ssa)
        {
            INT length = get_text_length(es);
            HFONT old_font = NULL;
            HDC udc = dc;

            if (!udc)
                udc = GetDC(es->hwndSelf);
            if (es->font)
                old_font = SelectObject(udc, es->font);

            if (es->style & ES_PASSWORD)
                ScriptStringAnalyse(udc, &es->password_char, length, (1.5*length+16), -1, SSA_LINK|SSA_FALLBACK|SSA_GLYPHS|SSA_PASSWORD, -1, NULL, NULL, NULL, NULL, NULL, &es->ssa);
            else
                ScriptStringAnalyse(udc, es->text, length, (1.5*length+16), -1, SSA_LINK|SSA_FALLBACK|SSA_GLYPHS, -1, NULL, NULL, NULL, NULL, NULL, &es->ssa);

            if (es->font)
                SelectObject(udc, old_font);
            if (udc != dc)
                ReleaseDC(es->hwndSelf, udc);
        }
        return es->ssa;
    }
    else
    {
        line_def = es->first_line_def;
        while (line_def && line)
        {
            line_def = line_def->next;
            line--;
        }

        return EDIT_UpdateUniscribeData_linedef(es,dc,line_def);
    }
}

static inline INT get_vertical_line_count(EDITSTATE *es)
{
    INT vlc = (es->format_rect.bottom - es->format_rect.top) / es->line_height;
    return max(1,vlc);
}

/*********************************************************************
 *
 *  EDIT_BuildLineDefs_ML
 *
 *  Build linked list of text lines.
 *  Lines can end with '\0' (last line), a character (if it is wrapped),
 *  a soft return '\r\r\n' or a hard return '\r\n'
 *
 */
static void EDIT_BuildLineDefs_ML(EDITSTATE *es, INT istart, INT iend, INT delta, HRGN hrgn)
{
    LPWSTR current_position, cp;
    INT fw;
    LINEDEF *current_line;
    LINEDEF *previous_line;
    LINEDEF *start_line;
    INT line_index = 0, nstart_line, nstart_index;
    INT line_count = es->line_count;
    INT orig_net_length;
    RECT rc;
    INT vlc;

    if (istart == iend && delta == 0)
        return;

    previous_line = NULL;
    current_line = es->first_line_def;

    /* Find starting line. istart must lie inside an existing line or
     * at the end of buffer */
    do {
        if (istart < current_line->index + current_line->length ||
                current_line->ending == END_0)
            break;

        previous_line = current_line;
        current_line = current_line->next;
        line_index++;
    } while (current_line);

    if (!current_line) /* Error occurred start is not inside previous buffer */
    {
        FIXME(" modification occurred outside buffer\n");
        return;
    }

    /* Remember start of modifications in order to calculate update region */
    nstart_line = line_index;
    nstart_index = current_line->index;

    /* We must start to reformat from the previous line since the modifications
     * may have caused the line to wrap upwards. */
    if (!(es->style & ES_AUTOHSCROLL) && line_index > 0)
    {
        line_index--;
        current_line = previous_line;
    }
    start_line = current_line;

    fw = es->format_rect.right - es->format_rect.left;
    current_position = es->text + current_line->index;
    vlc = get_vertical_line_count(es);
    do {
        if (current_line != start_line)
        {
            if (!current_line || current_line->index + delta > current_position - es->text)
            {
                /* The buffer has been expanded, create a new line and
                   insert it into the link list */
                LINEDEF *new_line = heap_alloc_zero(sizeof(*new_line));
                new_line->next = previous_line->next;
                previous_line->next = new_line;
                current_line = new_line;
                es->line_count++;
            }
            else if (current_line->index + delta < current_position - es->text)
            {
                /* The previous line merged with this line so we delete this extra entry */
                previous_line->next = current_line->next;
                heap_free(current_line);
                current_line = previous_line->next;
                es->line_count--;
                continue;
            }
            else /* current_line->index + delta == current_position */
            {
                if (current_position - es->text > iend)
                    break; /* We reached end of line modifications */
                /* else recalculate this line */
            }
        }

        current_line->index = current_position - es->text;
        orig_net_length = current_line->net_length;

        /* Find end of line */
        cp = current_position;
        while (*cp) {
                    if (*cp == '\n') break;
                    if ((*cp == '\r') && (*(cp + 1) == '\n'))
                        break;
                    cp++;
        }

        /* Mark type of line termination */
        if (!(*cp)) {
            current_line->ending = END_0;
            current_line->net_length = strlenW(current_position);
        } else if ((cp > current_position) && (*(cp - 1) == '\r')) {
            current_line->ending = END_SOFT;
            current_line->net_length = cp - current_position - 1;
                } else if (*cp == '\n') {
            current_line->ending = END_RICH;
            current_line->net_length = cp - current_position;
        } else {
            current_line->ending = END_HARD;
            current_line->net_length = cp - current_position;
        }

        if (current_line->net_length)
        {
            const SIZE *sz;
            EDIT_InvalidateUniscribeData_linedef(current_line);
            EDIT_UpdateUniscribeData_linedef(es, NULL, current_line);
            if (current_line->ssa)
            {
                sz = ScriptString_pSize(current_line->ssa);
                /* Calculate line width */
                current_line->width = sz->cx;
            }
            else current_line->width = es->char_width * current_line->net_length;
        }
        else current_line->width = 0;

        /* FIXME: check here for lines that are too wide even in AUTOHSCROLL (> 32767 ???) */

/* Line breaks just look back from the end and find the next break and try that. */

        if (!(es->style & ES_AUTOHSCROLL)) {
           if (current_line->width > fw && fw > es->char_width) {

            INT prev, next;
            int w;
            const SIZE *sz;
            float d;

            prev = current_line->net_length - 1;
            w = current_line->net_length;
            d = (float)current_line->width/(float)fw;
            if (d > 1.2f) d -= 0.2f;
            next = prev/d;
            if (next >= prev) next = prev-1;
            do {
                prev = EDIT_CallWordBreakProc(es, current_position - es->text,
                        next, current_line->net_length, WB_LEFT);
                current_line->net_length = prev;
                EDIT_InvalidateUniscribeData_linedef(current_line);
                EDIT_UpdateUniscribeData_linedef(es, NULL, current_line);
                if (current_line->ssa)
                    sz = ScriptString_pSize(current_line->ssa);
                else sz = 0;
                if (sz)
                    current_line->width = sz->cx;
                else
                    prev = 0;
                next = prev - 1;
            } while (prev && current_line->width > fw);
            current_line->net_length = w;

            if (prev == 0) { /* Didn't find a line break so force a break */
                INT *piDx;
                const INT *count;

                EDIT_InvalidateUniscribeData_linedef(current_line);
                EDIT_UpdateUniscribeData_linedef(es, NULL, current_line);

                if (current_line->ssa)
                {
                    count = ScriptString_pcOutChars(current_line->ssa);
                    piDx = heap_alloc(sizeof(INT) * (*count));
                    ScriptStringGetLogicalWidths(current_line->ssa,piDx);

                    prev = current_line->net_length-1;
                    do {
                        current_line->width -= piDx[prev];
                        prev--;
                    } while ( prev > 0 && current_line->width > fw);
                    if (prev<=0)
                        prev = 1;
                    heap_free(piDx);
                }
                else
                    prev = (fw / es->char_width);
            }

            /* If the first line we are calculating, wrapped before istart, we must
             * adjust istart in order for this to be reflected in the update region. */
            if (current_line->index == nstart_index && istart > current_line->index + prev)
                istart = current_line->index + prev;
            /* else if we are updating the previous line before the first line we
             * are re-calculating and it expanded */
            else if (current_line == start_line &&
                    current_line->index != nstart_index && orig_net_length < prev)
            {
              /* Line expanded due to an upwards line wrap so we must partially include
               * previous line in update region */
                nstart_line = line_index;
                nstart_index = current_line->index;
                istart = current_line->index + orig_net_length;
            }

            current_line->net_length = prev;
            current_line->ending = END_WRAP;

            if (current_line->net_length > 0)
            {
                EDIT_UpdateUniscribeData_linedef(es, NULL, current_line);
                if (current_line->ssa)
                {
                    sz = ScriptString_pSize(current_line->ssa);
                    current_line->width = sz->cx;
                }
                else
                    current_line->width = 0;
            }
            else current_line->width = 0;
            }
            else if (current_line == start_line &&
                             current_line->index != nstart_index &&
                             orig_net_length < current_line->net_length) {
            /* The previous line expanded but it's still not as wide as the client rect */
            /* The expansion is due to an upwards line wrap so we must partially include
               it in the update region */
            nstart_line = line_index;
            nstart_index = current_line->index;
            istart = current_line->index + orig_net_length;
            }
        }


        /* Adjust length to include line termination */
        switch (current_line->ending) {
        case END_SOFT:
            current_line->length = current_line->net_length + 3;
            break;
                case END_RICH:
            current_line->length = current_line->net_length + 1;
            break;
        case END_HARD:
            current_line->length = current_line->net_length + 2;
            break;
        case END_WRAP:
        case END_0:
            current_line->length = current_line->net_length;
            break;
        }
        es->text_width = max(es->text_width, current_line->width);
        current_position += current_line->length;
        previous_line = current_line;

        /* Discard data for non-visible lines. It will be calculated as needed */
        if ((line_index < es->y_offset) || (line_index > es->y_offset + vlc))
            EDIT_InvalidateUniscribeData_linedef(current_line);

        current_line = current_line->next;
        line_index++;
    } while (previous_line->ending != END_0);

    /* Finish adjusting line indexes by delta or remove hanging lines */
    if (previous_line->ending == END_0)
    {
        LINEDEF *pnext = NULL;

        previous_line->next = NULL;
        while (current_line)
        {
            pnext = current_line->next;
            EDIT_InvalidateUniscribeData_linedef(current_line);
            heap_free(current_line);
            current_line = pnext;
            es->line_count--;
        }
    }
    else if (delta != 0)
    {
        while (current_line)
        {
            current_line->index += delta;
            current_line = current_line->next;
        }
    }

    /* Calculate rest of modification rectangle */
    if (hrgn)
    {
        HRGN tmphrgn;
       /*
        * We calculate two rectangles. One for the first line which may have
        * an indent with respect to the format rect. The other is a format-width
        * rectangle that spans the rest of the lines that changed or moved.
        */
        rc.top = es->format_rect.top + nstart_line * es->line_height -
            (es->y_offset * es->line_height); /* Adjust for vertical scrollbar */
        rc.bottom = rc.top + es->line_height;
        if ((es->style & ES_CENTER) || (es->style & ES_RIGHT))
            rc.left = es->format_rect.left;
        else
#ifdef __REACTOS__ /* CORE-11475 */
            rc.left = (short)LOWORD(EDIT_EM_PosFromChar(es, nstart_index, FALSE));
#else
                        rc.left = LOWORD(EDIT_EM_PosFromChar(es, nstart_index, FALSE));
#endif
        rc.right = es->format_rect.right;
        SetRectRgn(hrgn, rc.left, rc.top, rc.right, rc.bottom);

        rc.top = rc.bottom;
        rc.left = es->format_rect.left;
        rc.right = es->format_rect.right;
       /*
        * If lines were added or removed we must re-paint the remainder of the
        * lines since the remaining lines were either shifted up or down.
        */
        if (line_count < es->line_count) /* We added lines */
            rc.bottom = es->line_count * es->line_height;
        else if (line_count > es->line_count) /* We removed lines */
            rc.bottom = line_count * es->line_height;
        else
            rc.bottom = line_index * es->line_height;
        rc.bottom += es->format_rect.top;
        rc.bottom -= (es->y_offset * es->line_height); /* Adjust for vertical scrollbar */
        tmphrgn = CreateRectRgn(rc.left, rc.top, rc.right, rc.bottom);
        CombineRgn(hrgn, hrgn, tmphrgn, RGN_OR);
        DeleteObject(tmphrgn);
    }
}

/*********************************************************************
 *
 *  EDIT_CalcLineWidth_SL
 *
 */
static void EDIT_CalcLineWidth_SL(EDITSTATE *es)
{
    EDIT_UpdateUniscribeData(es, NULL, 0);
    if (es->ssa)
    {
        const SIZE *size;
        size = ScriptString_pSize(es->ssa);
        es->text_width = size->cx;
    }
    else
        es->text_width = 0;
}

/*********************************************************************
 *
 *  EDIT_CharFromPos
 *
 *  Beware: This is not the function called on EM_CHARFROMPOS
 *      The position _can_ be outside the formatting / client
 *      rectangle
 *      The return value is only the character index
 *
 */
static INT EDIT_CharFromPos(EDITSTATE *es, INT x, INT y, LPBOOL after_wrap)
{
    INT index;

    if (es->style & ES_MULTILINE) {
        int trailing;
        INT line = (y - es->format_rect.top) / es->line_height + es->y_offset;
        INT line_index = 0;
        LINEDEF *line_def = es->first_line_def;
        EDIT_UpdateUniscribeData(es, NULL, line);
        while ((line > 0) && line_def->next) {
            line_index += line_def->length;
            line_def = line_def->next;
            line--;
        }

        x += es->x_offset - es->format_rect.left;
        if (es->style & ES_RIGHT)
            x -= (es->format_rect.right - es->format_rect.left) - line_def->width;
        else if (es->style & ES_CENTER)
            x -= ((es->format_rect.right - es->format_rect.left) - line_def->width) / 2;
        if (x >= line_def->width) {
            if (after_wrap)
                *after_wrap = (line_def->ending == END_WRAP);
            return line_index + line_def->net_length;
        }
        if (x <= 0 || !line_def->ssa) {
            if (after_wrap)
                *after_wrap = FALSE;
            return line_index;
        }

        ScriptStringXtoCP(line_def->ssa, x , &index, &trailing);
        if (trailing) index++;
        index += line_index;
        if (after_wrap)
            *after_wrap = ((index == line_index + line_def->net_length) &&
                            (line_def->ending == END_WRAP));
    } else {
        INT xoff = 0;
        INT trailing;
        if (after_wrap)
            *after_wrap = FALSE;
        x -= es->format_rect.left;
        if (!x)
            return es->x_offset;

        if (!es->x_offset)
        {
            INT indent = (es->format_rect.right - es->format_rect.left) - es->text_width;
            if (es->style & ES_RIGHT)
                x -= indent;
            else if (es->style & ES_CENTER)
                x -= indent / 2;
        }

        EDIT_UpdateUniscribeData(es, NULL, 0);
        if (es->x_offset)
        {
            if (es->ssa)
            {
                if (es->x_offset>= get_text_length(es))
                {
                    const SIZE *size;
                    size = ScriptString_pSize(es->ssa);
                    xoff = size->cx;
                }
                ScriptStringCPtoX(es->ssa, es->x_offset, FALSE, &xoff);
            }
            else
                xoff = 0;
        }
        if (x < 0)
        {
            if (x + xoff > 0 || !es->ssa)
            {
                ScriptStringXtoCP(es->ssa, x+xoff, &index, &trailing);
                if (trailing) index++;
            }
            else
                index = 0;
        }
        else
        {
            if (x)
            {
                const SIZE *size = NULL;
                if (es->ssa)
                    size = ScriptString_pSize(es->ssa);
                if (!size)
                    index = 0;
                else if (x > size->cx)
                    index = get_text_length(es);
                else if (es->ssa)
                {
                    ScriptStringXtoCP(es->ssa, x+xoff, &index, &trailing);
                    if (trailing) index++;
                }
                else
                    index = 0;
            }
            else
                index = es->x_offset;
        }
    }
    return index;
}


/*********************************************************************
 *
 *  EDIT_ConfinePoint
 *
 *  adjusts the point to be within the formatting rectangle
 *  (so CharFromPos returns the nearest _visible_ character)
 *
 */
static void EDIT_ConfinePoint(const EDITSTATE *es, LPINT x, LPINT y)
{
    *x = min(max(*x, es->format_rect.left), es->format_rect.right - 1);
    *y = min(max(*y, es->format_rect.top), es->format_rect.bottom - 1);
}


/*********************************************************************
 *
 *  EM_LINEFROMCHAR
 *
 */
static INT EDIT_EM_LineFromChar(EDITSTATE *es, INT index)
{
    INT line;
    LINEDEF *line_def;

    if (!(es->style & ES_MULTILINE))
        return 0;
    if (index > (INT)get_text_length(es))
        return es->line_count - 1;
    if (index == -1)
        index = min(es->selection_start, es->selection_end);

    line = 0;
    line_def = es->first_line_def;
    index -= line_def->length;
    while ((index >= 0) && line_def->next) {
        line++;
        line_def = line_def->next;
        index -= line_def->length;
    }
    return line;
}


/*********************************************************************
 *
 *  EM_LINEINDEX
 *
 */
static INT EDIT_EM_LineIndex(const EDITSTATE *es, INT line)
{
    INT line_index;
    const LINEDEF *line_def;

    if (!(es->style & ES_MULTILINE))
        return 0;
    if (line >= es->line_count)
        return -1;

    line_index = 0;
    line_def = es->first_line_def;
    if (line == -1) {
        INT index = es->selection_end - line_def->length;
        while ((index >= 0) && line_def->next) {
            line_index += line_def->length;
            line_def = line_def->next;
            index -= line_def->length;
        }
    } else {
        while (line > 0) {
            line_index += line_def->length;
            line_def = line_def->next;
            line--;
        }
    }
    return line_index;
}


/*********************************************************************
 *
 *  EM_LINELENGTH
 *
 */
static INT EDIT_EM_LineLength(EDITSTATE *es, INT index)
{
    LINEDEF *line_def;

    if (!(es->style & ES_MULTILINE))
        return get_text_length(es);

    if (index == -1) {
        /* get the number of remaining non-selected chars of selected lines */
        INT32 l; /* line number */
        INT32 li; /* index of first char in line */
        INT32 count;
        l = EDIT_EM_LineFromChar(es, es->selection_start);
        /* # chars before start of selection area */
        count = es->selection_start - EDIT_EM_LineIndex(es, l);
        l = EDIT_EM_LineFromChar(es, es->selection_end);
        /* # chars after end of selection */
        li = EDIT_EM_LineIndex(es, l);
        count += li + EDIT_EM_LineLength(es, li) - es->selection_end;
        return count;
    }
    line_def = es->first_line_def;
    index -= line_def->length;
    while ((index >= 0) && line_def->next) {
        line_def = line_def->next;
        index -= line_def->length;
    }
    return line_def->net_length;
}


/*********************************************************************
 *
 *  EM_POSFROMCHAR
 *
 */
static LRESULT EDIT_EM_PosFromChar(EDITSTATE *es, INT index, BOOL after_wrap)
{
    INT len = get_text_length(es);
    INT l;
    INT li;
    INT x = 0;
    INT y = 0;
    INT w;
    INT lw;
    LINEDEF *line_def;

    index = min(index, len);
    if (es->style & ES_MULTILINE) {
        l = EDIT_EM_LineFromChar(es, index);
        EDIT_UpdateUniscribeData(es, NULL, l);

        y = (l - es->y_offset) * es->line_height;
        li = EDIT_EM_LineIndex(es, l);
        if (after_wrap && (li == index) && l) {
            INT l2 = l - 1;
            line_def = es->first_line_def;
            while (l2) {
                line_def = line_def->next;
                l2--;
            }
            if (line_def->ending == END_WRAP) {
                l--;
                y -= es->line_height;
                li = EDIT_EM_LineIndex(es, l);
            }
        }

        line_def = es->first_line_def;
        while (line_def->index != li)
            line_def = line_def->next;

        lw = line_def->width;
        w = es->format_rect.right - es->format_rect.left;
        if (line_def->ssa)
        {
            ScriptStringCPtoX(line_def->ssa, (index - 1) - li, TRUE, &x);
            x -= es->x_offset;
        }
        else
#ifdef __REACTOS__ /* CORE-15780 */
            x = (lw > 0 ? es->x_offset : x - es->x_offset);
#else
            x = es->x_offset;
#endif

        if (es->style & ES_RIGHT)
            x = w - (lw - x);
        else if (es->style & ES_CENTER)
            x += (w - lw) / 2;
    } else {
        INT xoff = 0;
        INT xi = 0;
        EDIT_UpdateUniscribeData(es, NULL, 0);
        if (es->x_offset)
        {
            if (es->ssa)
            {
                if (es->x_offset >= get_text_length(es))
                {
                    int leftover = es->x_offset - get_text_length(es);
                    if (es->ssa)
                    {
                        const SIZE *size;
                        size = ScriptString_pSize(es->ssa);
                        xoff = size->cx;
                    }
                    else
                        xoff = 0;
                    xoff += es->char_width * leftover;
                }
                else
                    ScriptStringCPtoX(es->ssa, es->x_offset, FALSE, &xoff);
            }
            else
                xoff = 0;
        }
        if (index)
        {
            if (index >= get_text_length(es))
            {
                if (es->ssa)
                {
                    const SIZE *size;
                    size = ScriptString_pSize(es->ssa);
                    xi = size->cx;
                }
                else
                    xi = 0;
            }
            else if (es->ssa)
                ScriptStringCPtoX(es->ssa, index, FALSE, &xi);
            else
                xi = 0;
        }
        x = xi - xoff;

        if (index >= es->x_offset) {
            if (!es->x_offset && (es->style & (ES_RIGHT | ES_CENTER)))
            {
                w = es->format_rect.right - es->format_rect.left;
                if (w > es->text_width)
                {
                    if (es->style & ES_RIGHT)
                        x += w - es->text_width;
                    else if (es->style & ES_CENTER)
                        x += (w - es->text_width) / 2;
                }
            }
        }
        y = 0;
    }
    x += es->format_rect.left;
    y += es->format_rect.top;
    return MAKELONG((INT16)x, (INT16)y);
}


/*********************************************************************
 *
 *  EDIT_GetLineRect
 *
 *  Calculates the bounding rectangle for a line from a starting
 *  column to an ending column.
 *
 */
static void EDIT_GetLineRect(EDITSTATE *es, INT line, INT scol, INT ecol, LPRECT rc)
{
    SCRIPT_STRING_ANALYSIS ssa;
    INT line_index = 0;
    INT pt1, pt2, pt3;

    if (es->style & ES_MULTILINE)
    {
        const LINEDEF *line_def = NULL;
        rc->top = es->format_rect.top + (line - es->y_offset) * es->line_height;
        if (line >= es->line_count)
            return;

        line_def = es->first_line_def;
        if (line == -1) {
            INT index = es->selection_end - line_def->length;
            while ((index >= 0) && line_def->next) {
                line_index += line_def->length;
                line_def = line_def->next;
                index -= line_def->length;
            }
        } else {
            while (line > 0) {
                line_index += line_def->length;
                line_def = line_def->next;
                line--;
            }
        }
        ssa = line_def->ssa;
    }
    else
    {
        line_index = 0;
        rc->top = es->format_rect.top;
        ssa = es->ssa;
    }

    rc->bottom = rc->top + es->line_height;
    pt1 = (scol == 0) ? es->format_rect.left : (short)LOWORD(EDIT_EM_PosFromChar(es, line_index + scol, TRUE));
    pt2 = (ecol == -1) ? es->format_rect.right : (short)LOWORD(EDIT_EM_PosFromChar(es, line_index + ecol, TRUE));
    if (ssa)
    {
        ScriptStringCPtoX(ssa, scol, FALSE, &pt3);
        pt3+=es->format_rect.left;
    }
    else pt3 = pt1;
    rc->right = max(max(pt1 , pt2),pt3);
    rc->left = min(min(pt1, pt2),pt3);
}


static inline void text_buffer_changed(EDITSTATE *es)
{
    es->text_length = (UINT)-1;

    heap_free( es->logAttr );
    es->logAttr = NULL;
    EDIT_InvalidateUniscribeData(es);
}

/*********************************************************************
 * EDIT_LockBuffer
 *
 */
static void EDIT_LockBuffer(EDITSTATE *es)
{
    if (!es->text)
    {
        if (!es->hloc32W)
            return;

        es->text = LocalLock(es->hloc32W);
    }

    es->lock_count++;
}


/*********************************************************************
 *
 *  EDIT_UnlockBuffer
 *
 */
static void EDIT_UnlockBuffer(EDITSTATE *es, BOOL force)
{
    /* Edit window might be already destroyed */
    if (!IsWindow(es->hwndSelf))
    {
        WARN("edit hwnd %p already destroyed\n", es->hwndSelf);
        return;
    }

    if (!es->lock_count)
    {
        ERR("lock_count == 0 ... please report\n");
        return;
    }

    if (!es->text)
    {
        ERR("es->text == 0 ... please report\n");
        return;
    }

    if (force || (es->lock_count == 1))
    {
        if (es->hloc32W)
        {
            LocalUnlock(es->hloc32W);
            es->text = NULL;
        }
        else
        {
            ERR("no buffer ... please report\n");
            return;
        }

    }

    es->lock_count--;
}


/*********************************************************************
 *
 *  EDIT_MakeFit
 *
 * Try to fit size + 1 characters in the buffer.
 */
static BOOL EDIT_MakeFit(EDITSTATE *es, UINT size)
{
    HLOCAL hNew32W;

    if (size <= es->buffer_size)
        return TRUE;

    TRACE("trying to ReAlloc to %d+1 characters\n", size);

        /* Force edit to unlock its buffer. es->text now NULL */
    EDIT_UnlockBuffer(es, TRUE);

    if (es->hloc32W) {
        UINT alloc_size = ROUND_TO_GROW((size + 1) * sizeof(WCHAR));
        if ((hNew32W = LocalReAlloc(es->hloc32W, alloc_size, LMEM_MOVEABLE | LMEM_ZEROINIT))) {
        TRACE("Old 32 bit handle %p, new handle %p\n", es->hloc32W, hNew32W);
        es->hloc32W = hNew32W;
        es->buffer_size = LocalSize(hNew32W)/sizeof(WCHAR) - 1;
        }
    }

    EDIT_LockBuffer(es);

    if (es->buffer_size < size) {
        WARN("FAILED !  We now have %d+1\n", es->buffer_size);
        EDIT_NOTIFY_PARENT(es, EN_ERRSPACE);
        return FALSE;
    } else {
        TRACE("We now have %d+1\n", es->buffer_size);
        return TRUE;
    }
}


/*********************************************************************
 *
 *  EDIT_MakeUndoFit
 *
 *  Try to fit size + 1 bytes in the undo buffer.
 *
 */
static BOOL EDIT_MakeUndoFit(EDITSTATE *es, UINT size)
{
    UINT alloc_size;

    if (size <= es->undo_buffer_size)
        return TRUE;

    TRACE("trying to ReAlloc to %d+1\n", size);

    alloc_size = ROUND_TO_GROW((size + 1) * sizeof(WCHAR));
    if ((es->undo_text = HeapReAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, es->undo_text, alloc_size))) {
        es->undo_buffer_size = alloc_size/sizeof(WCHAR) - 1;
        return TRUE;
    }
    else
    {
        WARN("FAILED !  We now have %d+1\n", es->undo_buffer_size);
        return FALSE;
    }
}


/*********************************************************************
 *
 *  EDIT_UpdateTextRegion
 *
 */
static void EDIT_UpdateTextRegion(EDITSTATE *es, HRGN hrgn, BOOL bErase)
{
    if (es->flags & EF_UPDATE) {
        es->flags &= ~EF_UPDATE;
        EDIT_NOTIFY_PARENT(es, EN_UPDATE);
    }
    InvalidateRgn(es->hwndSelf, hrgn, bErase);
}


/*********************************************************************
 *
 *  EDIT_UpdateText
 *
 */
static void EDIT_UpdateText(EDITSTATE *es, const RECT *rc, BOOL bErase)
{
    if (es->flags & EF_UPDATE) {
        es->flags &= ~EF_UPDATE;
        EDIT_NOTIFY_PARENT(es, EN_UPDATE);
    }
    InvalidateRect(es->hwndSelf, rc, bErase);
}

/*********************************************************************
 *
 *  EDIT_SL_InvalidateText
 *
 *  Called from EDIT_InvalidateText().
 *  Does the job for single-line controls only.
 *
 */
static void EDIT_SL_InvalidateText(EDITSTATE *es, INT start, INT end)
{
    RECT line_rect;
    RECT rc;

    EDIT_GetLineRect(es, 0, start, end, &line_rect);
    if (IntersectRect(&rc, &line_rect, &es->format_rect))
        EDIT_UpdateText(es, &rc, TRUE);
}

/*********************************************************************
 *
 *  EDIT_ML_InvalidateText
 *
 *  Called from EDIT_InvalidateText().
 *  Does the job for multi-line controls only.
 *
 */
static void EDIT_ML_InvalidateText(EDITSTATE *es, INT start, INT end)
{
    INT vlc = get_vertical_line_count(es);
    INT sl = EDIT_EM_LineFromChar(es, start);
    INT el = EDIT_EM_LineFromChar(es, end);
    INT sc;
    INT ec;
    RECT rc1;
    RECT rcWnd;
    RECT rcLine;
    RECT rcUpdate;
    INT l;

    if ((el < es->y_offset) || (sl > es->y_offset + vlc))
        return;

    sc = start - EDIT_EM_LineIndex(es, sl);
    ec = end - EDIT_EM_LineIndex(es, el);
    if (sl < es->y_offset) {
        sl = es->y_offset;
        sc = 0;
    }
    if (el > es->y_offset + vlc) {
        el = es->y_offset + vlc;
        ec = EDIT_EM_LineLength(es, EDIT_EM_LineIndex(es, el));
    }
    GetClientRect(es->hwndSelf, &rc1);
    IntersectRect(&rcWnd, &rc1, &es->format_rect);
    if (sl == el) {
        EDIT_GetLineRect(es, sl, sc, ec, &rcLine);
        if (IntersectRect(&rcUpdate, &rcWnd, &rcLine))
            EDIT_UpdateText(es, &rcUpdate, TRUE);
    } else {
        EDIT_GetLineRect(es, sl, sc,
                EDIT_EM_LineLength(es,
                    EDIT_EM_LineIndex(es, sl)),
                &rcLine);
        if (IntersectRect(&rcUpdate, &rcWnd, &rcLine))
            EDIT_UpdateText(es, &rcUpdate, TRUE);
        for (l = sl + 1 ; l < el ; l++) {
            EDIT_GetLineRect(es, l, 0,
                EDIT_EM_LineLength(es,
                    EDIT_EM_LineIndex(es, l)),
                &rcLine);
            if (IntersectRect(&rcUpdate, &rcWnd, &rcLine))
                EDIT_UpdateText(es, &rcUpdate, TRUE);
        }
        EDIT_GetLineRect(es, el, 0, ec, &rcLine);
        if (IntersectRect(&rcUpdate, &rcWnd, &rcLine))
            EDIT_UpdateText(es, &rcUpdate, TRUE);
    }
}


/*********************************************************************
 *
 *  EDIT_InvalidateText
 *
 *  Invalidate the text from offset start up to, but not including,
 *  offset end.  Useful for (re)painting the selection.
 *  Regions outside the linewidth are not invalidated.
 *  end == -1 means end == TextLength.
 *  start and end need not be ordered.
 *
 */
static void EDIT_InvalidateText(EDITSTATE *es, INT start, INT end)
{
    if (end == start)
        return;

    if (end == -1)
        end = get_text_length(es);

    if (end < start) {
        INT tmp = start;
        start = end;
        end = tmp;
    }

    if (es->style & ES_MULTILINE)
        EDIT_ML_InvalidateText(es, start, end);
    else
        EDIT_SL_InvalidateText(es, start, end);
}


/*********************************************************************
 *
 *  EDIT_EM_SetSel
 *
 *  note:   unlike the specs say: the order of start and end
 *      _is_ preserved in Windows.  (i.e. start can be > end)
 *      In other words: this handler is OK
 *
 */
static BOOL EDIT_EM_SetSel(EDITSTATE *es, UINT start, UINT end, BOOL after_wrap)
{
    UINT old_start = es->selection_start;
    UINT old_end = es->selection_end;
    UINT len = get_text_length(es);

        if (start == old_start && end == old_end)
            return FALSE;

    if (start == (UINT)-1) {
        start = es->selection_end;
        end = es->selection_end;
    } else {
        start = min(start, len);
        end = min(end, len);
    }
    es->selection_start = start;
    es->selection_end = end;
    if (after_wrap)
        es->flags |= EF_AFTER_WRAP;
    else
        es->flags &= ~EF_AFTER_WRAP;
    /* Compute the necessary invalidation region. */
    /* Note that we don't need to invalidate regions which have
     * "never" been selected, or those which are "still" selected.
     * In fact, every time we hit a selection boundary, we can
     * *toggle* whether we need to invalidate.  Thus we can optimize by
     * *sorting* the interval endpoints.  Let's assume that we sort them
     * in this order:
     *        start <= end <= old_start <= old_end
     * Knuth 5.3.1 (p 183) assures us that this can be done optimally
     * in 5 comparisons; i.e. it is impossible to do better than the
     * following: */
        ORDER_UINT(end, old_end);
        ORDER_UINT(start, old_start);
        ORDER_UINT(old_start, old_end);
        ORDER_UINT(start, end);
    /* Note that at this point 'end' and 'old_start' are not in order, but
     * start is definitely the min. and old_end is definitely the max. */
    if (end != old_start)
        {
/*
 * One can also do
 *          ORDER_UINT32(end, old_start);
 *          EDIT_InvalidateText(es, start, end);
 *          EDIT_InvalidateText(es, old_start, old_end);
 * in place of the following if statement.
 * (That would complete the optimal five-comparison four-element sort.)
 */
            if (old_start > end )
            {
                EDIT_InvalidateText(es, start, end);
                EDIT_InvalidateText(es, old_start, old_end);
            }
            else
            {
                EDIT_InvalidateText(es, start, old_start);
                EDIT_InvalidateText(es, end, old_end);
            }
    }
        else EDIT_InvalidateText(es, start, old_end);

        return TRUE;
}


/*********************************************************************
 *
 *  EDIT_UpdateScrollInfo
 *
 */
static void EDIT_UpdateScrollInfo(EDITSTATE *es)
{
    if ((es->style & WS_VSCROLL) && !(es->flags & EF_VSCROLL_TRACK))
    {
    SCROLLINFO si;
    si.cbSize   = sizeof(SCROLLINFO);
    si.fMask    = SIF_PAGE | SIF_POS | SIF_RANGE | SIF_DISABLENOSCROLL;
    si.nMin     = 0;
    si.nMax     = es->line_count - 1;
    si.nPage    = (es->format_rect.bottom - es->format_rect.top) / es->line_height;
    si.nPos     = es->y_offset;
    TRACE("SB_VERT, nMin=%d, nMax=%d, nPage=%d, nPos=%d\n",
        si.nMin, si.nMax, si.nPage, si.nPos);
    SetScrollInfo(es->hwndSelf, SB_VERT, &si, TRUE);
    }

    if ((es->style & WS_HSCROLL) && !(es->flags & EF_HSCROLL_TRACK))
    {
    SCROLLINFO si;
    si.cbSize   = sizeof(SCROLLINFO);
    si.fMask    = SIF_PAGE | SIF_POS | SIF_RANGE | SIF_DISABLENOSCROLL;
    si.nMin     = 0;
    si.nMax     = es->text_width - 1;
    si.nPage    = es->format_rect.right - es->format_rect.left;
    si.nPos     = es->x_offset;
    TRACE("SB_HORZ, nMin=%d, nMax=%d, nPage=%d, nPos=%d\n",
        si.nMin, si.nMax, si.nPage, si.nPos);
    SetScrollInfo(es->hwndSelf, SB_HORZ, &si, TRUE);
    }
}


/*********************************************************************
 *
 *  EDIT_EM_LineScroll_internal
 *
 *  Version of EDIT_EM_LineScroll for internal use.
 *  It doesn't refuse if ES_MULTILINE is set and assumes that
 *  dx is in pixels, dy - in lines.
 *
 */
static BOOL EDIT_EM_LineScroll_internal(EDITSTATE *es, INT dx, INT dy)
{
    INT nyoff;
    INT x_offset_in_pixels;
    INT lines_per_page = (es->format_rect.bottom - es->format_rect.top) /
                  es->line_height;

    if (es->style & ES_MULTILINE)
    {
        x_offset_in_pixels = es->x_offset;
    }
    else
    {
        dy = 0;
        x_offset_in_pixels = (short)LOWORD(EDIT_EM_PosFromChar(es, es->x_offset, FALSE));
    }

    if (-dx > x_offset_in_pixels)
        dx = -x_offset_in_pixels;
    if (dx > es->text_width - x_offset_in_pixels)
        dx = es->text_width - x_offset_in_pixels;
    nyoff = max(0, es->y_offset + dy);
    if (nyoff >= es->line_count - lines_per_page)
        nyoff = max(0, es->line_count - lines_per_page);
    dy = (es->y_offset - nyoff) * es->line_height;
    if (dx || dy) {
        RECT rc1;
        RECT rc;

        es->y_offset = nyoff;
        if(es->style & ES_MULTILINE)
            es->x_offset += dx;
        else
            es->x_offset += dx / es->char_width;

        GetClientRect(es->hwndSelf, &rc1);
        IntersectRect(&rc, &rc1, &es->format_rect);
        ScrollWindowEx(es->hwndSelf, -dx, dy,
                NULL, &rc, NULL, NULL, SW_INVALIDATE);
        /* force scroll info update */
        EDIT_UpdateScrollInfo(es);
    }
    if (dx && !(es->flags & EF_HSCROLL_TRACK))
        EDIT_NOTIFY_PARENT(es, EN_HSCROLL);
    if (dy && !(es->flags & EF_VSCROLL_TRACK))
        EDIT_NOTIFY_PARENT(es, EN_VSCROLL);
    return TRUE;
}

/*********************************************************************
 *
 *  EM_LINESCROLL
 *
 *  NOTE: dx is in average character widths, dy - in lines;
 *
 */
static BOOL EDIT_EM_LineScroll(EDITSTATE *es, INT dx, INT dy)
{
    if (!(es->style & ES_MULTILINE))
        return FALSE;

    dx *= es->char_width;
    return EDIT_EM_LineScroll_internal(es, dx, dy);
}


/*********************************************************************
 *
 *  EM_SCROLL
 *
 */
static LRESULT EDIT_EM_Scroll(EDITSTATE *es, INT action)
{
    INT dy;

    if (!(es->style & ES_MULTILINE))
        return (LRESULT)FALSE;

    dy = 0;

    switch (action) {
    case SB_LINEUP:
        if (es->y_offset)
            dy = -1;
        break;
    case SB_LINEDOWN:
        if (es->y_offset < es->line_count - 1)
            dy = 1;
        break;
    case SB_PAGEUP:
        if (es->y_offset)
            dy = -(es->format_rect.bottom - es->format_rect.top) / es->line_height;
        break;
    case SB_PAGEDOWN:
        if (es->y_offset < es->line_count - 1)
            dy = (es->format_rect.bottom - es->format_rect.top) / es->line_height;
        break;
    default:
        return (LRESULT)FALSE;
    }
    if (dy) {
        INT vlc = get_vertical_line_count(es);
        /* check if we are going to move too far */
        if(es->y_offset + dy > es->line_count - vlc)
        dy = max(es->line_count - vlc, 0) - es->y_offset;

        /* Notification is done in EDIT_EM_LineScroll */
        if(dy) {
        EDIT_EM_LineScroll(es, 0, dy);
        return MAKELONG(dy, TRUE);
        }

    }
    return (LRESULT)FALSE;
}


/*********************************************************************
 *
 *  EDIT_SetCaretPos
 *
 */
static void EDIT_SetCaretPos(EDITSTATE *es, INT pos,
                 BOOL after_wrap)
{
    LRESULT res = EDIT_EM_PosFromChar(es, pos, after_wrap);
    TRACE("%d - %dx%d\n", pos, (short)LOWORD(res), (short)HIWORD(res));
    SetCaretPos((short)LOWORD(res), (short)HIWORD(res));
}


/*********************************************************************
 *
 *  EM_SCROLLCARET
 *
 */
static void EDIT_EM_ScrollCaret(EDITSTATE *es)
{
    if (es->style & ES_MULTILINE) {
        INT l;
        INT vlc;
        INT ww;
        INT cw = es->char_width;
        INT x;
        INT dy = 0;
        INT dx = 0;

        l = EDIT_EM_LineFromChar(es, es->selection_end);
        x = (short)LOWORD(EDIT_EM_PosFromChar(es, es->selection_end, es->flags & EF_AFTER_WRAP));
        vlc = get_vertical_line_count(es);
        if (l >= es->y_offset + vlc)
            dy = l - vlc + 1 - es->y_offset;
        if (l < es->y_offset)
            dy = l - es->y_offset;
        ww = es->format_rect.right - es->format_rect.left;
        if (x < es->format_rect.left)
            dx = x - es->format_rect.left - ww / HSCROLL_FRACTION / cw * cw;
        if (x > es->format_rect.right)
            dx = x - es->format_rect.left - (HSCROLL_FRACTION - 1) * ww / HSCROLL_FRACTION / cw * cw;
        if (dy || dx || (es->y_offset && (es->line_count - es->y_offset < vlc)))
        {
            /* check if we are going to move too far */
            if(es->x_offset + dx + ww > es->text_width)
            dx = es->text_width - ww - es->x_offset;
            if(dx || dy || (es->y_offset && (es->line_count - es->y_offset < vlc)))
            EDIT_EM_LineScroll_internal(es, dx, dy);
        }
    } else {
        INT x;
        INT goal;
        INT format_width;

        x = (short)LOWORD(EDIT_EM_PosFromChar(es, es->selection_end, FALSE));
        format_width = es->format_rect.right - es->format_rect.left;
        if (x < es->format_rect.left) {
            goal = es->format_rect.left + format_width / HSCROLL_FRACTION;
            do {
                es->x_offset--;
                x = (short)LOWORD(EDIT_EM_PosFromChar(es, es->selection_end, FALSE));
            } while ((x < goal) && es->x_offset);
            /* FIXME: use ScrollWindow() somehow to improve performance */
            EDIT_UpdateText(es, NULL, TRUE);
        } else if (x > es->format_rect.right) {
            INT x_last;
            INT len = get_text_length(es);
            goal = es->format_rect.right - format_width / HSCROLL_FRACTION;
            do {
                es->x_offset++;
                x = (short)LOWORD(EDIT_EM_PosFromChar(es, es->selection_end, FALSE));
                x_last = (short)LOWORD(EDIT_EM_PosFromChar(es, len, FALSE));
            } while ((x > goal) && (x_last > es->format_rect.right));
            /* FIXME: use ScrollWindow() somehow to improve performance */
            EDIT_UpdateText(es, NULL, TRUE);
        }
    }

    if(es->flags & EF_FOCUSED)
    EDIT_SetCaretPos(es, es->selection_end, es->flags & EF_AFTER_WRAP);
}


/*********************************************************************
 *
 *  EDIT_MoveBackward
 *
 */
static void EDIT_MoveBackward(EDITSTATE *es, BOOL extend)
{
    INT e = es->selection_end;

    if (e) {
        e--;
        if ((es->style & ES_MULTILINE) && e &&
                (es->text[e - 1] == '\r') && (es->text[e] == '\n')) {
            e--;
            if (e && (es->text[e - 1] == '\r'))
                e--;
        }
    }
    EDIT_EM_SetSel(es, extend ? es->selection_start : e, e, FALSE);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MoveDown_ML
 *
 *  Only for multi line controls
 *  Move the caret one line down, on a column with the nearest
 *  x coordinate on the screen (might be a different column).
 *
 */
static void EDIT_MoveDown_ML(EDITSTATE *es, BOOL extend)
{
    INT s = es->selection_start;
    INT e = es->selection_end;
    BOOL after_wrap = (es->flags & EF_AFTER_WRAP);
    LRESULT pos = EDIT_EM_PosFromChar(es, e, after_wrap);
    INT x = (short)LOWORD(pos);
    INT y = (short)HIWORD(pos);

    e = EDIT_CharFromPos(es, x, y + es->line_height, &after_wrap);
    if (!extend)
        s = e;
    EDIT_EM_SetSel(es, s, e, after_wrap);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MoveEnd
 *
 */
static void EDIT_MoveEnd(EDITSTATE *es, BOOL extend, BOOL ctrl)
{
    BOOL after_wrap = FALSE;
    INT e;

    /* Pass a high value in x to make sure of receiving the end of the line */
    if (!ctrl && (es->style & ES_MULTILINE))
        e = EDIT_CharFromPos(es, 0x3fffffff,
            HIWORD(EDIT_EM_PosFromChar(es, es->selection_end, es->flags & EF_AFTER_WRAP)), &after_wrap);
    else
        e = get_text_length(es);
    EDIT_EM_SetSel(es, extend ? es->selection_start : e, e, after_wrap);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MoveForward
 *
 */
static void EDIT_MoveForward(EDITSTATE *es, BOOL extend)
{
    INT e = es->selection_end;

    if (es->text[e]) {
        e++;
        if ((es->style & ES_MULTILINE) && (es->text[e - 1] == '\r')) {
            if (es->text[e] == '\n')
                e++;
            else if ((es->text[e] == '\r') && (es->text[e + 1] == '\n'))
                e += 2;
        }
    }
    EDIT_EM_SetSel(es, extend ? es->selection_start : e, e, FALSE);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MoveHome
 *
 *  Home key: move to beginning of line.
 *
 */
static void EDIT_MoveHome(EDITSTATE *es, BOOL extend, BOOL ctrl)
{
    INT e;

    /* Pass the x_offset in x to make sure of receiving the first position of the line */
    if (!ctrl && (es->style & ES_MULTILINE))
        e = EDIT_CharFromPos(es, -es->x_offset,
            HIWORD(EDIT_EM_PosFromChar(es, es->selection_end, es->flags & EF_AFTER_WRAP)), NULL);
    else
        e = 0;
    EDIT_EM_SetSel(es, extend ? es->selection_start : e, e, FALSE);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MovePageDown_ML
 *
 *  Only for multi line controls
 *  Move the caret one page down, on a column with the nearest
 *  x coordinate on the screen (might be a different column).
 *
 */
static void EDIT_MovePageDown_ML(EDITSTATE *es, BOOL extend)
{
    INT s = es->selection_start;
    INT e = es->selection_end;
    BOOL after_wrap = (es->flags & EF_AFTER_WRAP);
    LRESULT pos = EDIT_EM_PosFromChar(es, e, after_wrap);
    INT x = (short)LOWORD(pos);
    INT y = (short)HIWORD(pos);

    e = EDIT_CharFromPos(es, x,
        y + (es->format_rect.bottom - es->format_rect.top),
        &after_wrap);
    if (!extend)
        s = e;
    EDIT_EM_SetSel(es, s, e, after_wrap);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MovePageUp_ML
 *
 *  Only for multi line controls
 *  Move the caret one page up, on a column with the nearest
 *  x coordinate on the screen (might be a different column).
 *
 */
static void EDIT_MovePageUp_ML(EDITSTATE *es, BOOL extend)
{
    INT s = es->selection_start;
    INT e = es->selection_end;
    BOOL after_wrap = (es->flags & EF_AFTER_WRAP);
    LRESULT pos = EDIT_EM_PosFromChar(es, e, after_wrap);
    INT x = (short)LOWORD(pos);
    INT y = (short)HIWORD(pos);

    e = EDIT_CharFromPos(es, x,
        y - (es->format_rect.bottom - es->format_rect.top),
        &after_wrap);
    if (!extend)
        s = e;
    EDIT_EM_SetSel(es, s, e, after_wrap);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MoveUp_ML
 *
 *  Only for multi line controls
 *  Move the caret one line up, on a column with the nearest
 *  x coordinate on the screen (might be a different column).
 *
 */
static void EDIT_MoveUp_ML(EDITSTATE *es, BOOL extend)
{
    INT s = es->selection_start;
    INT e = es->selection_end;
    BOOL after_wrap = (es->flags & EF_AFTER_WRAP);
    LRESULT pos = EDIT_EM_PosFromChar(es, e, after_wrap);
    INT x = (short)LOWORD(pos);
    INT y = (short)HIWORD(pos);

    e = EDIT_CharFromPos(es, x, y - es->line_height, &after_wrap);
    if (!extend)
        s = e;
    EDIT_EM_SetSel(es, s, e, after_wrap);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MoveWordBackward
 *
 */
static void EDIT_MoveWordBackward(EDITSTATE *es, BOOL extend)
{
    INT s = es->selection_start;
    INT e = es->selection_end;
    INT l;
    INT ll;
    INT li;

    l = EDIT_EM_LineFromChar(es, e);
    ll = EDIT_EM_LineLength(es, e);
    li = EDIT_EM_LineIndex(es, l);
    if (e - li == 0) {
        if (l) {
            li = EDIT_EM_LineIndex(es, l - 1);
            e = li + EDIT_EM_LineLength(es, li);
        }
    } else {
        e = li + EDIT_CallWordBreakProc(es, li, e - li, ll, WB_LEFT);
    }
    if (!extend)
        s = e;
    EDIT_EM_SetSel(es, s, e, FALSE);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_MoveWordForward
 *
 */
static void EDIT_MoveWordForward(EDITSTATE *es, BOOL extend)
{
    INT s = es->selection_start;
    INT e = es->selection_end;
    INT l;
    INT ll;
    INT li;

    l = EDIT_EM_LineFromChar(es, e);
    ll = EDIT_EM_LineLength(es, e);
    li = EDIT_EM_LineIndex(es, l);
    if (e - li == ll) {
        if ((es->style & ES_MULTILINE) && (l != es->line_count - 1))
            e = EDIT_EM_LineIndex(es, l + 1);
    } else {
        e = li + EDIT_CallWordBreakProc(es,
                li, e - li + 1, ll, WB_RIGHT);
    }
    if (!extend)
        s = e;
    EDIT_EM_SetSel(es, s, e, FALSE);
    EDIT_EM_ScrollCaret(es);
}


/*********************************************************************
 *
 *  EDIT_PaintText
 *
 */
static INT EDIT_PaintText(EDITSTATE *es, HDC dc, INT x, INT y, INT line, INT col, INT count, BOOL rev)
{
    COLORREF BkColor;
    COLORREF TextColor;
    LOGFONTW underline_font;
    HFONT hUnderline = 0;
    HFONT old_font = 0;
    INT ret;
    INT li;
    INT BkMode;
    SIZE size;

    if (!count)
        return 0;
    BkMode = GetBkMode(dc);
    BkColor = GetBkColor(dc);
    TextColor = GetTextColor(dc);
    if (rev) {
            if (es->composition_len == 0)
            {
            SetBkColor(dc, GetSysColor(COLOR_HIGHLIGHT));
            SetTextColor(dc, GetSysColor(COLOR_HIGHLIGHTTEXT));
            SetBkMode( dc, OPAQUE);
            }
        else
        {
            HFONT current = GetCurrentObject(dc,OBJ_FONT);
            GetObjectW(current,sizeof(LOGFONTW),&underline_font);
            underline_font.lfUnderline = TRUE;
            hUnderline = CreateFontIndirectW(&underline_font);
            old_font = SelectObject(dc,hUnderline);
            }
    }
    li = EDIT_EM_LineIndex(es, line);
    if (es->style & ES_MULTILINE) {
        ret = (INT)LOWORD(TabbedTextOutW(dc, x, y, es->text + li + col, count,
                    es->tabs_count, es->tabs, es->format_rect.left - es->x_offset));
    } else {
        TextOutW(dc, x, y, es->text + li + col, count);
        GetTextExtentPoint32W(dc, es->text + li + col, count, &size);
        ret = size.cx;
    }
    if (rev) {
        if (es->composition_len == 0)
        {
            SetBkColor(dc, BkColor);
            SetTextColor(dc, TextColor);
            SetBkMode( dc, BkMode);
        }
        else
        {
            if (old_font)
                SelectObject(dc,old_font);
            if (hUnderline)
                DeleteObject(hUnderline);
            }
    }
    return ret;
}


/*********************************************************************
 *
 *  EDIT_PaintLine
 *
 */
static void EDIT_PaintLine(EDITSTATE *es, HDC dc, INT line, BOOL rev)
{
    INT s = 0;
    INT e = 0;
    INT li = 0;
    INT ll = 0;
    INT x;
    INT y;
    LRESULT pos;
    SCRIPT_STRING_ANALYSIS ssa;

    if (es->style & ES_MULTILINE) {
        INT vlc = get_vertical_line_count(es);

        if ((line < es->y_offset) || (line > es->y_offset + vlc) || (line >= es->line_count))
            return;
    } else if (line)
        return;

    TRACE("line=%d\n", line);

    ssa = EDIT_UpdateUniscribeData(es, dc, line);
    pos = EDIT_EM_PosFromChar(es, EDIT_EM_LineIndex(es, line), FALSE);
    x = (short)LOWORD(pos);
    y = (short)HIWORD(pos);

    if (es->style & ES_MULTILINE)
    {
        int line_idx = line;
        x =  -es->x_offset;
        if (es->style & ES_RIGHT || es->style & ES_CENTER)
        {
            LINEDEF *line_def = es->first_line_def;
            int w, lw;

            while (line_def && line_idx)
            {
                line_def = line_def->next;
                line_idx--;
            }
            w = es->format_rect.right - es->format_rect.left;
            lw = line_def->width;

            if (es->style & ES_RIGHT)
                x = w - (lw - x);
            else if (es->style & ES_CENTER)
                x += (w - lw) / 2;
        }
        x += es->format_rect.left;
    }

    if (rev)
    {
        li = EDIT_EM_LineIndex(es, line);
        ll = EDIT_EM_LineLength(es, li);
        s = min(es->selection_start, es->selection_end);
        e = max(es->selection_start, es->selection_end);
        s = min(li + ll, max(li, s));
        e = min(li + ll, max(li, e));
    }

    if (ssa)
        ScriptStringOut(ssa, x, y, 0, &es->format_rect, s - li, e - li, FALSE);
    else if (rev && (s != e) &&
            ((es->flags & EF_FOCUSED) || (es->style & ES_NOHIDESEL))) {
        x += EDIT_PaintText(es, dc, x, y, line, 0, s - li, FALSE);
        x += EDIT_PaintText(es, dc, x, y, line, s - li, e - s, TRUE);
        x += EDIT_PaintText(es, dc, x, y, line, e - li, li + ll - e, FALSE);
    } else
        x += EDIT_PaintText(es, dc, x, y, line, 0, ll, FALSE);
}


/*********************************************************************
 *
 *  EDIT_AdjustFormatRect
 *
 *  Adjusts the format rectangle for the current font and the
 *  current client rectangle.
 *
 */
static void EDIT_AdjustFormatRect(EDITSTATE *es)
{
    RECT ClientRect;

    es->format_rect.right = max(es->format_rect.right, es->format_rect.left + es->char_width);
    if (es->style & ES_MULTILINE)
    {
        INT fw, vlc, max_x_offset, max_y_offset;

        vlc = get_vertical_line_count(es);
        es->format_rect.bottom = es->format_rect.top + vlc * es->line_height;

        /* correct es->x_offset */
        fw = es->format_rect.right - es->format_rect.left;
        max_x_offset = es->text_width - fw;
        if(max_x_offset < 0) max_x_offset = 0;
        if(es->x_offset > max_x_offset)
        es->x_offset = max_x_offset;

        /* correct es->y_offset */
        max_y_offset = es->line_count - vlc;
        if(max_y_offset < 0) max_y_offset = 0;
        if(es->y_offset > max_y_offset)
        es->y_offset = max_y_offset;

        /* force scroll info update */
        EDIT_UpdateScrollInfo(es);
    }
    else
    /* Windows doesn't care to fix text placement for SL controls */
        es->format_rect.bottom = es->format_rect.top + es->line_height;

    /* Always stay within the client area */
    GetClientRect(es->hwndSelf, &ClientRect);
    es->format_rect.bottom = min(es->format_rect.bottom, ClientRect.bottom);

    if ((es->style & ES_MULTILINE) && !(es->style & ES_AUTOHSCROLL))
        EDIT_BuildLineDefs_ML(es, 0, get_text_length(es), 0, NULL);

    EDIT_SetCaretPos(es, es->selection_end, es->flags & EF_AFTER_WRAP);
}


/*********************************************************************
 *
 *  EDIT_SetRectNP
 *
 *  note:   this is not (exactly) the handler called on EM_SETRECTNP
 *      it is also used to set the rect of a single line control
 *
 */
static void EDIT_SetRectNP(EDITSTATE *es, const RECT *rc)
{
    LONG_PTR ExStyle;
    INT bw, bh;
    ExStyle = GetWindowLongPtrW(es->hwndSelf, GWL_EXSTYLE);

    CopyRect(&es->format_rect, rc);

    if (ExStyle & WS_EX_CLIENTEDGE) {
        es->format_rect.left++;
        es->format_rect.right--;

        if (es->format_rect.bottom - es->format_rect.top
            >= es->line_height + 2)
        {
            es->format_rect.top++;
            es->format_rect.bottom--;
        }
    }
    else if (es->style & WS_BORDER) {
        bw = GetSystemMetrics(SM_CXBORDER) + 1;
        bh = GetSystemMetrics(SM_CYBORDER) + 1;
                InflateRect(&es->format_rect, -bw, 0);
                if (es->format_rect.bottom - es->format_rect.top >= es->line_height + 2 * bh)
                    InflateRect(&es->format_rect, 0, -bh);
    }

    es->format_rect.left += es->left_margin;
    es->format_rect.right -= es->right_margin;
    EDIT_AdjustFormatRect(es);
}


/*********************************************************************
 *
 *  EM_CHARFROMPOS
 *
 *      returns line number (not index) in high-order word of result.
 *      NB : Q137805 is unclear about this. POINT * pointer in lParam apply
 *      to Richedit, not to the edit control. Original documentation is valid.
 *  FIXME: do the specs mean to return -1 if outside client area or
 *      if outside formatting rectangle ???
 *
 */
static LRESULT EDIT_EM_CharFromPos(EDITSTATE *es, INT x, INT y)
{
    POINT pt;
    RECT rc;
    INT index;

    pt.x = x;
    pt.y = y;
    GetClientRect(es->hwndSelf, &rc);
    if (!PtInRect(&rc, pt))
        return -1;

    index = EDIT_CharFromPos(es, x, y, NULL);
    return MAKELONG(index, EDIT_EM_LineFromChar(es, index));
}


/*********************************************************************
 *
 *  EM_FMTLINES
 *
 * Enable or disable soft breaks.
 *
 * This means: insert or remove the soft linebreak character (\r\r\n).
 * Take care to check if the text still fits the buffer after insertion.
 * If not, notify with EN_ERRSPACE.
 *
 */
static BOOL EDIT_EM_FmtLines(EDITSTATE *es, BOOL add_eol)
{
    es->flags &= ~EF_USE_SOFTBRK;
    if (add_eol) {
        es->flags |= EF_USE_SOFTBRK;
        FIXME("soft break enabled, not implemented\n");
    }
    return add_eol;
}


/*********************************************************************
 *
 *  EM_GETHANDLE
 *
 *  Hopefully this won't fire back at us.
 *  We always start with a fixed buffer in the local heap.
 *  Despite of the documentation says that the local heap is used
 *  only if DS_LOCALEDIT flag is set, NT and 2000 always allocate
 *  buffer on the local heap.
 *
 */
static HLOCAL EDIT_EM_GetHandle(EDITSTATE *es)
{
    if (!(es->style & ES_MULTILINE))
        return 0;

    EDIT_UnlockBuffer(es, TRUE);

    /* The text buffer handle belongs to the app */
    es->hlocapp = es->hloc32W;

    TRACE("Returning %p, LocalSize() = %ld\n", es->hlocapp, LocalSize(es->hlocapp));
    return es->hlocapp;
}


/*********************************************************************
 *
 *  EM_GETLINE
 *
 */
static INT EDIT_EM_GetLine(EDITSTATE *es, INT line, LPWSTR dst)
{
    INT line_len, dst_len;
    LPWSTR src;
    INT i;

    if (es->style & ES_MULTILINE)
    {
        if (line >= es->line_count)
            return 0;
    }
    else
        line = 0;

    i = EDIT_EM_LineIndex(es, line);
    src = es->text + i;
    line_len = EDIT_EM_LineLength(es, i);
    dst_len = *(WORD *)dst;

    if (dst_len <= line_len)
    {
        memcpy(dst, src, dst_len * sizeof(WCHAR));
        return dst_len;
    }
    else /* Append 0 if enough space */
    {
        memcpy(dst, src, line_len * sizeof(WCHAR));
        dst[line_len] = 0;
        return line_len;
    }
}


/*********************************************************************
 *
 *  EM_GETSEL
 *
 */
static LRESULT EDIT_EM_GetSel(const EDITSTATE *es, PUINT start, PUINT end)
{
    UINT s = es->selection_start;
    UINT e = es->selection_end;

    ORDER_UINT(s, e);
    if (start)
        *start = s;
    if (end)
        *end = e;
    return MAKELONG(s, e);
}


/*********************************************************************
 *
 *  EM_REPLACESEL
 *
 *  FIXME: handle ES_NUMBER and ES_OEMCONVERT here
 *
 */
static void EDIT_EM_ReplaceSel(EDITSTATE *es, BOOL can_undo, const WCHAR *lpsz_replace, UINT strl,
                               BOOL send_update, BOOL honor_limit)
{
    UINT tl = get_text_length(es);
    UINT utl;
    UINT s;
    UINT e;
    UINT i;
    UINT size;
    LPWSTR p;
    HRGN hrgn = 0;
    LPWSTR buf = NULL;
    UINT bufl;

    TRACE("%s, can_undo %d, send_update %d\n",
        debugstr_wn(lpsz_replace, strl), can_undo, send_update);

    s = es->selection_start;
    e = es->selection_end;

    EDIT_InvalidateUniscribeData(es);
    if ((s == e) && !strl)
        return;

    ORDER_UINT(s, e);

    size = tl - (e - s) + strl;
    if (!size)
        es->text_width = 0;

    /* Issue the EN_MAXTEXT notification and continue with replacing text
         * so that buffer limit is honored. */
    if ((honor_limit) && (size > es->buffer_limit)) {
        EDIT_NOTIFY_PARENT(es, EN_MAXTEXT);
        /* Buffer limit can be smaller than the actual length of text in combobox */
        if (es->buffer_limit < (tl - (e-s)))
            strl = 0;
        else
            strl = min(strl, es->buffer_limit - (tl - (e-s)));
    }

    if (!EDIT_MakeFit(es, tl - (e - s) + strl))
        return;

    if (e != s) {
        /* there is something to be deleted */
        TRACE("deleting stuff.\n");
        bufl = e - s;
        buf = heap_alloc((bufl + 1) * sizeof(WCHAR));
        if (!buf) return;
        memcpy(buf, es->text + s, bufl * sizeof(WCHAR));
        buf[bufl] = 0; /* ensure 0 termination */
        /* now delete */
        strcpyW(es->text + s, es->text + e);
                text_buffer_changed(es);
    }
    if (strl) {
        /* there is an insertion */
        tl = get_text_length(es);
        TRACE("inserting stuff (tl %d, strl %d, selstart %d (%s), text %s)\n", tl, strl, s, debugstr_w(es->text + s), debugstr_w(es->text));
        for (p = es->text + tl ; p >= es->text + s ; p--)
            p[strl] = p[0];
        for (i = 0 , p = es->text + s ; i < strl ; i++)
            p[i] = lpsz_replace[i];
        if(es->style & ES_UPPERCASE)
            CharUpperBuffW(p, strl);
        else if(es->style & ES_LOWERCASE)
            CharLowerBuffW(p, strl);
                text_buffer_changed(es);
    }
    if (es->style & ES_MULTILINE)
    {
        INT st = min(es->selection_start, es->selection_end);
        INT vlc = get_vertical_line_count(es);

        hrgn = CreateRectRgn(0, 0, 0, 0);
        EDIT_BuildLineDefs_ML(es, st, st + strl,
                strl - abs(es->selection_end - es->selection_start), hrgn);
        /* if text is too long undo all changes */
        if (honor_limit && !(es->style & ES_AUTOVSCROLL) && (es->line_count > vlc)) {
            if (strl)
                strcpyW(es->text + e, es->text + e + strl);
            if (e != s)
                for (i = 0 , p = es->text ; i < e - s ; i++)
                    p[i + s] = buf[i];
                        text_buffer_changed(es);
            EDIT_BuildLineDefs_ML(es, s, e,
                abs(es->selection_end - es->selection_start) - strl, hrgn);
            strl = 0;
            e = s;
            hrgn = CreateRectRgn(0, 0, 0, 0);
            EDIT_NOTIFY_PARENT(es, EN_MAXTEXT);
        }
    }
    else {
        INT fw = es->format_rect.right - es->format_rect.left;
        EDIT_InvalidateUniscribeData(es);
        EDIT_CalcLineWidth_SL(es);
        /* remove chars that don't fit */
        if (honor_limit && !(es->style & ES_AUTOHSCROLL) && (es->text_width > fw)) {
            while ((es->text_width > fw) && s + strl >= s) {
                strcpyW(es->text + s + strl - 1, es->text + s + strl);
                strl--;
                es->text_length = -1;
                EDIT_InvalidateUniscribeData(es);
                EDIT_CalcLineWidth_SL(es);
            }
                        text_buffer_changed(es);
            EDIT_NOTIFY_PARENT(es, EN_MAXTEXT);
        }
    }

    if (e != s) {
        if (can_undo) {
            utl = strlenW(es->undo_text);
            if (!es->undo_insert_count && (*es->undo_text && (s == es->undo_position))) {
                /* undo-buffer is extended to the right */
                EDIT_MakeUndoFit(es, utl + e - s);
                memcpy(es->undo_text + utl, buf, (e - s)*sizeof(WCHAR));
                (es->undo_text + utl)[e - s] = 0; /* ensure 0 termination */
            } else if (!es->undo_insert_count && (*es->undo_text && (e == es->undo_position))) {
                /* undo-buffer is extended to the left */
                EDIT_MakeUndoFit(es, utl + e - s);
                for (p = es->undo_text + utl ; p >= es->undo_text ; p--)
                    p[e - s] = p[0];
                for (i = 0 , p = es->undo_text ; i < e - s ; i++)
                    p[i] = buf[i];
                es->undo_position = s;
            } else {
                /* new undo-buffer */
                EDIT_MakeUndoFit(es, e - s);
                memcpy(es->undo_text, buf, (e - s)*sizeof(WCHAR));
                es->undo_text[e - s] = 0; /* ensure 0 termination */
                es->undo_position = s;
            }
            /* any deletion makes the old insertion-undo invalid */
            es->undo_insert_count = 0;
        } else
            EDIT_EM_EmptyUndoBuffer(es);
    }
    if (strl) {
        if (can_undo) {
            if ((s == es->undo_position) ||
                ((es->undo_insert_count) &&
                (s == es->undo_position + es->undo_insert_count)))
                /*
                 * insertion is new and at delete position or
                 * an extension to either left or right
                 */
                es->undo_insert_count += strl;
            else {
                /* new insertion undo */
                es->undo_position = s;
                es->undo_insert_count = strl;
                /* new insertion makes old delete-buffer invalid */
                *es->undo_text = '\0';
            }
        } else
            EDIT_EM_EmptyUndoBuffer(es);
    }

    heap_free(buf);

    s += strl;

    /* If text has been deleted and we're right or center aligned then scroll rightward */
    if (es->style & (ES_RIGHT | ES_CENTER))
    {
        INT delta = strl - abs(es->selection_end - es->selection_start);

        if (delta < 0 && es->x_offset)
        {
            if (abs(delta) > es->x_offset)
                es->x_offset = 0;
            else
                es->x_offset += delta;
        }
    }

    EDIT_EM_SetSel(es, s, s, FALSE);
    es->flags |= EF_MODIFIED;
    if (send_update) es->flags |= EF_UPDATE;
    if (hrgn)
    {
        EDIT_UpdateTextRegion(es, hrgn, TRUE);
        DeleteObject(hrgn);
    }
    else
            EDIT_UpdateText(es, NULL, TRUE);

    EDIT_EM_ScrollCaret(es);

    /* force scroll info update */
    EDIT_UpdateScrollInfo(es);


        if(send_update || (es->flags & EF_UPDATE))
    {
        es->flags &= ~EF_UPDATE;
        EDIT_NOTIFY_PARENT(es, EN_CHANGE);
    }
    EDIT_InvalidateUniscribeData(es);
}


/*********************************************************************
 *
 *  EM_SETHANDLE
 *
 *  FIXME:  ES_LOWERCASE, ES_UPPERCASE, ES_OEMCONVERT, ES_NUMBER ???
 *
 */
static void EDIT_EM_SetHandle(EDITSTATE *es, HLOCAL hloc)
{
    if (!(es->style & ES_MULTILINE))
        return;

    if (!hloc)
        return;

    EDIT_UnlockBuffer(es, TRUE);

    es->hloc32W = hloc;
    es->buffer_size = LocalSize(es->hloc32W)/sizeof(WCHAR) - 1;

    /* The text buffer handle belongs to the control */
    es->hlocapp = NULL;

    EDIT_LockBuffer(es);
    text_buffer_changed(es);

    es->x_offset = es->y_offset = 0;
    es->selection_start = es->selection_end = 0;
    EDIT_EM_EmptyUndoBuffer(es);
    es->flags &= ~EF_MODIFIED;
    es->flags &= ~EF_UPDATE;
    EDIT_BuildLineDefs_ML(es, 0, get_text_length(es), 0, NULL);
    EDIT_UpdateText(es, NULL, TRUE);
    EDIT_EM_ScrollCaret(es);
    /* force scroll info update */
    EDIT_UpdateScrollInfo(es);
}


/*********************************************************************
 *
 *  EM_SETLIMITTEXT
 *
 *  NOTE: this version currently implements WinNT limits
 *
 */
static void EDIT_EM_SetLimitText(EDITSTATE *es, UINT limit)
{
    if (!limit) limit = ~0u;
    if (!(es->style & ES_MULTILINE)) limit = min(limit, 0x7ffffffe);
    es->buffer_limit = limit;
}


/*********************************************************************
 *
 *  EM_SETMARGINS
 *
 * EC_USEFONTINFO is used as a left or right value i.e. lParam and not as an
 * action wParam despite what the docs say. EC_USEFONTINFO calculates the
 * margin according to the textmetrics of the current font.
 *
 * When EC_USEFONTINFO is used in the non_cjk case the margins only
 * change if the edit control is equal to or larger than a certain
 * size.  Though there is an exception for the empty client rect case
 * with small font sizes.
 */
static BOOL is_cjk(UINT charset)
{
    switch(charset)
    {
    case SHIFTJIS_CHARSET:
    case HANGUL_CHARSET:
    case GB2312_CHARSET:
    case CHINESEBIG5_CHARSET:
        return TRUE;
    }
    /* HANGUL_CHARSET is strange, though treated as CJK by Win 8, it is
     * not by other versions including Win 10. */
    return FALSE;
}

static void EDIT_EM_SetMargins(EDITSTATE *es, INT action,
                   WORD left, WORD right, BOOL repaint)
{
    TEXTMETRICW tm;
    INT default_left_margin  = 0; /* in pixels */
    INT default_right_margin = 0; /* in pixels */

        /* Set the default margins depending on the font */
        if (es->font && (left == EC_USEFONTINFO || right == EC_USEFONTINFO)) {
            HDC dc = GetDC(es->hwndSelf);
            HFONT old_font = SelectObject(dc, es->font);
            LONG width = GdiGetCharDimensions(dc, &tm, NULL);
            RECT rc;

            /* The default margins are only non zero for TrueType or Vector fonts */
            if (tm.tmPitchAndFamily & ( TMPF_VECTOR | TMPF_TRUETYPE )) {
                if (!is_cjk(tm.tmCharSet)) {
                    default_left_margin = width / 2;
                    default_right_margin = width / 2;

                    GetClientRect(es->hwndSelf, &rc);
                    if (rc.right - rc.left < (width / 2 + width) * 2 &&
                        (width >= 28 || !IsRectEmpty(&rc)) ) {
                        default_left_margin = es->left_margin;
                        default_right_margin = es->right_margin;
                    }
                } else {
                    /* FIXME: figure out the CJK values. They are not affected by the client rect. */
                    default_left_margin = width / 2;
                    default_right_margin = width / 2;
                }
            }
            SelectObject(dc, old_font);
            ReleaseDC(es->hwndSelf, dc);
        }

    if (action & EC_LEFTMARGIN) {
        es->format_rect.left -= es->left_margin;
        if (left != EC_USEFONTINFO)
            es->left_margin = left;
        else
            es->left_margin = default_left_margin;
        es->format_rect.left += es->left_margin;
    }

    if (action & EC_RIGHTMARGIN) {
        es->format_rect.right += es->right_margin;
        if (right != EC_USEFONTINFO)
            es->right_margin = right;
        else
            es->right_margin = default_right_margin;
        es->format_rect.right -= es->right_margin;
    }

    if (action & (EC_LEFTMARGIN | EC_RIGHTMARGIN)) {
        EDIT_AdjustFormatRect(es);
        if (repaint) EDIT_UpdateText(es, NULL, TRUE);
    }

    TRACE("left=%d, right=%d\n", es->left_margin, es->right_margin);
}


/*********************************************************************
 *
 *  EM_SETPASSWORDCHAR
 *
 */
static void EDIT_EM_SetPasswordChar(EDITSTATE *es, WCHAR c)
{
    LONG style;

    if (es->style & ES_MULTILINE)
        return;

    if (es->password_char == c)
        return;

        style = GetWindowLongW( es->hwndSelf, GWL_STYLE );
    es->password_char = c;
    if (c) {
            SetWindowLongW( es->hwndSelf, GWL_STYLE, style | ES_PASSWORD );
            es->style |= ES_PASSWORD;
    } else {
            SetWindowLongW( es->hwndSelf, GWL_STYLE, style & ~ES_PASSWORD );
            es->style &= ~ES_PASSWORD;
    }
    EDIT_InvalidateUniscribeData(es);
    EDIT_UpdateText(es, NULL, TRUE);
}


/*********************************************************************
 *
 *  EM_SETTABSTOPS
 *
 */
static BOOL EDIT_EM_SetTabStops(EDITSTATE *es, INT count, const INT *tabs)
{
    if (!(es->style & ES_MULTILINE))
        return FALSE;
        heap_free(es->tabs);
    es->tabs_count = count;
    if (!count)
        es->tabs = NULL;
    else {
        es->tabs = heap_alloc(count * sizeof(INT));
        memcpy(es->tabs, tabs, count * sizeof(INT));
    }
    EDIT_InvalidateUniscribeData(es);
    return TRUE;
}


/*********************************************************************
 *
 *  EM_SETWORDBREAKPROC
 *
 */
static void EDIT_EM_SetWordBreakProc(EDITSTATE *es, EDITWORDBREAKPROCW wbp)
{
    if (es->word_break_proc == wbp)
        return;

    es->word_break_proc = wbp;

    if ((es->style & ES_MULTILINE) && !(es->style & ES_AUTOHSCROLL)) {
        EDIT_BuildLineDefs_ML(es, 0, get_text_length(es), 0, NULL);
        EDIT_UpdateText(es, NULL, TRUE);
    }
}


/*********************************************************************
 *
 *  EM_UNDO / WM_UNDO
 *
 */
static BOOL EDIT_EM_Undo(EDITSTATE *es)
{
    INT ulength;
    LPWSTR utext;

    /* As per MSDN spec, for a single-line edit control,
       the return value is always TRUE */
    if( es->style & ES_READONLY )
            return !(es->style & ES_MULTILINE);

    ulength = strlenW(es->undo_text);

    utext = heap_alloc((ulength + 1) * sizeof(WCHAR));

    strcpyW(utext, es->undo_text);

    TRACE("before UNDO:insertion length = %d, deletion buffer = %s\n",
             es->undo_insert_count, debugstr_w(utext));

    EDIT_EM_SetSel(es, es->undo_position, es->undo_position + es->undo_insert_count, FALSE);
    EDIT_EM_EmptyUndoBuffer(es);
    EDIT_EM_ReplaceSel(es, TRUE, utext, ulength, TRUE, TRUE);
    EDIT_EM_SetSel(es, es->undo_position, es->undo_position + es->undo_insert_count, FALSE);
        /* send the notification after the selection start and end are set */
        EDIT_NOTIFY_PARENT(es, EN_CHANGE);
    EDIT_EM_ScrollCaret(es);
    heap_free(utext);

    TRACE("after UNDO:insertion length = %d, deletion buffer = %s\n",
            es->undo_insert_count, debugstr_w(es->undo_text));
    return TRUE;
}


/* Helper function for WM_CHAR
 *
 * According to an MSDN blog article titled "Just because you're a control
 * doesn't mean that you're necessarily inside a dialog box," multiline edit
 * controls without ES_WANTRETURN would attempt to detect whether it is inside
 * a dialog box or not.
 */
static inline BOOL EDIT_IsInsideDialog(EDITSTATE *es)
{
    return (es->flags & EF_DIALOGMODE);
}


/*********************************************************************
 *
 *  WM_PASTE
 *
 */
static void EDIT_WM_Paste(EDITSTATE *es)
{
    HGLOBAL hsrc;
    LPWSTR src, ptr;
    int len;

    /* Protect read-only edit control from modification */
    if(es->style & ES_READONLY)
        return;

    OpenClipboard(es->hwndSelf);
    if ((hsrc = GetClipboardData(CF_UNICODETEXT))) {
        src = GlobalLock(hsrc);
                len = strlenW(src);
        /* Protect single-line edit against pasting new line character */
        if (!(es->style & ES_MULTILINE) && ((ptr = strchrW(src, '\n')))) {
            len = ptr - src;
            if (len && src[len - 1] == '\r')
                --len;
        }
                EDIT_EM_ReplaceSel(es, TRUE, src, len, TRUE, TRUE);
        GlobalUnlock(hsrc);
    }
        else if (es->style & ES_PASSWORD) {
            /* clear selected text in password edit box even with empty clipboard */
            EDIT_EM_ReplaceSel(es, TRUE, NULL, 0, TRUE, TRUE);
        }
    CloseClipboard();
}


/*********************************************************************
 *
 *  WM_COPY
 *
 */
static void EDIT_WM_Copy(EDITSTATE *es)
{
    INT s = min(es->selection_start, es->selection_end);
    INT e = max(es->selection_start, es->selection_end);
    HGLOBAL hdst;
    LPWSTR dst;
    DWORD len;

    if (e == s) return;

    len = e - s;
    hdst = GlobalAlloc(GMEM_MOVEABLE | GMEM_DDESHARE, (len + 1) * sizeof(WCHAR));
    dst = GlobalLock(hdst);
    memcpy(dst, es->text + s, len * sizeof(WCHAR));
    dst[len] = 0; /* ensure 0 termination */
    TRACE("%s\n", debugstr_w(dst));
    GlobalUnlock(hdst);
    OpenClipboard(es->hwndSelf);
    EmptyClipboard();
    SetClipboardData(CF_UNICODETEXT, hdst);
    CloseClipboard();
}


/*********************************************************************
 *
 *  WM_CLEAR
 *
 */
static inline void EDIT_WM_Clear(EDITSTATE *es)
{
    /* Protect read-only edit control from modification */
    if(es->style & ES_READONLY)
        return;

    EDIT_EM_ReplaceSel(es, TRUE, NULL, 0, TRUE, TRUE);
}


/*********************************************************************
 *
 *  WM_CUT
 *
 */
static inline void EDIT_WM_Cut(EDITSTATE *es)
{
    EDIT_WM_Copy(es);
    EDIT_WM_Clear(es);
}


/*********************************************************************
 *
 *  WM_CHAR
 *
 */
static LRESULT EDIT_WM_Char(EDITSTATE *es, WCHAR c)
{
        BOOL control;

    control = GetKeyState(VK_CONTROL) & 0x8000;

    switch (c) {
    case '\r':
            /* If it's not a multiline edit box, it would be ignored below.
             * For multiline edit without ES_WANTRETURN, we have to make a
             * special case.
             */
            if ((es->style & ES_MULTILINE) && !(es->style & ES_WANTRETURN))
                if (EDIT_IsInsideDialog(es))
                    break;
    case '\n':
        if (es->style & ES_MULTILINE) {
            if (es->style & ES_READONLY) {
                EDIT_MoveHome(es, FALSE, FALSE);
                EDIT_MoveDown_ML(es, FALSE);
            } else {
                static const WCHAR cr_lfW[] = {'\r','\n'};
                EDIT_EM_ReplaceSel(es, TRUE, cr_lfW, 2, TRUE, TRUE);
            }
        }
        break;
    case '\t':
        if ((es->style & ES_MULTILINE) && !(es->style & ES_READONLY))
        {
            static const WCHAR tabW[] = {'\t'};
                        if (EDIT_IsInsideDialog(es))
                            break;
            EDIT_EM_ReplaceSel(es, TRUE, tabW, 1, TRUE, TRUE);
        }
        break;
    case VK_BACK:
        if (!(es->style & ES_READONLY) && !control) {
            if (es->selection_start != es->selection_end)
                EDIT_WM_Clear(es);
            else {
                /* delete character left of caret */
                EDIT_EM_SetSel(es, (UINT)-1, 0, FALSE);
                EDIT_MoveBackward(es, TRUE);
                EDIT_WM_Clear(es);
            }
        }
        break;
    case 0x03: /* ^C */
        if (!(es->style & ES_PASSWORD))
            SendMessageW(es->hwndSelf, WM_COPY, 0, 0);
        break;
    case 0x16: /* ^V */
            if (!(es->style & ES_READONLY))
            SendMessageW(es->hwndSelf, WM_PASTE, 0, 0);
        break;
    case 0x18: /* ^X */
            if (!((es->style & ES_READONLY) || (es->style & ES_PASSWORD)))
            SendMessageW(es->hwndSelf, WM_CUT, 0, 0);
        break;
    case 0x1A: /* ^Z */
            if (!(es->style & ES_READONLY))
            SendMessageW(es->hwndSelf, WM_UNDO, 0, 0);
        break;

    default:
        /*If Edit control style is ES_NUMBER allow users to key in only numeric values*/
        if( (es->style & ES_NUMBER) && !( c >= '0' && c <= '9') )
            break;

        if (!(es->style & ES_READONLY) && (c >= ' ') && (c != 127))
            EDIT_EM_ReplaceSel(es, TRUE, &c, 1, TRUE, TRUE);
        break;
    }
    return 1;
}


/*********************************************************************
 *
 *  EDIT_ContextMenuCommand
 *
 */
static void EDIT_ContextMenuCommand(EDITSTATE *es, UINT id)
{
    switch (id) {
        case EM_UNDO:
                        SendMessageW(es->hwndSelf, WM_UNDO, 0, 0);
            break;
        case WM_CUT:
                        SendMessageW(es->hwndSelf, WM_CUT, 0, 0);
            break;
        case WM_COPY:
                        SendMessageW(es->hwndSelf, WM_COPY, 0, 0);
            break;
        case WM_PASTE:
                        SendMessageW(es->hwndSelf, WM_PASTE, 0, 0);
            break;
        case WM_CLEAR:
                        SendMessageW(es->hwndSelf, WM_CLEAR, 0, 0);
            break;
        case EM_SETSEL:
                        SendMessageW(es->hwndSelf, EM_SETSEL, 0, -1);
            break;
        default:
            ERR("unknown menu item, please report\n");
            break;
    }
}


/*********************************************************************
 *
 *  WM_CONTEXTMENU
 *
 *  Note: the resource files resource/sysres_??.rc cannot define a
 *      single popup menu.  Hence we use a (dummy) menubar
 *      containing the single popup menu as its first item.
 *
 *  FIXME: the message identifiers have been chosen arbitrarily,
 *      hence we use MF_BYPOSITION.
 *      We might as well use the "real" values (anybody knows ?)
 *      The menu definition is in resources/sysres_??.rc.
 *      Once these are OK, we better use MF_BYCOMMAND here
 *      (as we do in EDIT_WM_Command()).
 *
 */
static void EDIT_WM_ContextMenu(EDITSTATE *es, INT x, INT y)
{
    HMENU menu = LoadMenuA(GetModuleHandleA("user32.dll"), "EDITMENU");
    HMENU popup = GetSubMenu(menu, 0);
    UINT start = es->selection_start;
    UINT end = es->selection_end;
    UINT cmd;
    POINT pt;

    ORDER_UINT(start, end);

    /* undo */
    EnableMenuItem(popup, 0, MF_BYPOSITION | (EDIT_EM_CanUndo(es) && !(es->style & ES_READONLY) ? MF_ENABLED : MF_GRAYED));
    /* cut */
    EnableMenuItem(popup, 2, MF_BYPOSITION | ((end - start) && !(es->style & ES_PASSWORD) && !(es->style & ES_READONLY) ? MF_ENABLED : MF_GRAYED));
    /* copy */
    EnableMenuItem(popup, 3, MF_BYPOSITION | ((end - start) && !(es->style & ES_PASSWORD) ? MF_ENABLED : MF_GRAYED));
    /* paste */
    EnableMenuItem(popup, 4, MF_BYPOSITION | (IsClipboardFormatAvailable(CF_UNICODETEXT) && !(es->style & ES_READONLY) ? MF_ENABLED : MF_GRAYED));
    /* delete */
    EnableMenuItem(popup, 5, MF_BYPOSITION | ((end - start) && !(es->style & ES_READONLY) ? MF_ENABLED : MF_GRAYED));
    /* select all */
    EnableMenuItem(popup, 7, MF_BYPOSITION | (start || (end != get_text_length(es)) ? MF_ENABLED : MF_GRAYED));

    pt.x = x;
    pt.y = y;

    if (pt.x == -1 && pt.y == -1) /* passed via VK_APPS press/release */
    {
        RECT rc;

        /* Windows places the menu at the edit's center in this case */
        GetClientRect(es->hwndSelf, &rc);
        pt.x = rc.left + (rc.right - rc.left) / 2;
        pt.y = rc.top + (rc.bottom - rc.top) / 2;
        ClientToScreen(es->hwndSelf, &pt);
    }

    if (!(es->flags & EF_FOCUSED))
        SetFocus(es->hwndSelf);

    cmd = TrackPopupMenu(popup, TPM_LEFTALIGN | TPM_RIGHTBUTTON | TPM_RETURNCMD | TPM_NONOTIFY,
            pt.x, pt.y, 0, es->hwndSelf, NULL);

    if (cmd)
        EDIT_ContextMenuCommand(es, cmd);

    DestroyMenu(menu);
}


/*********************************************************************
 *
 *  WM_GETTEXT
 *
 */
static INT EDIT_WM_GetText(const EDITSTATE *es, INT count, LPWSTR dst)
{
    if (!count)
        return 0;

    lstrcpynW(dst, es->text, count);
    return strlenW(dst);
}

/*********************************************************************
 *
 *  EDIT_CheckCombo
 *
 */
static BOOL EDIT_CheckCombo(EDITSTATE *es, UINT msg, INT key)
{
    HWND hLBox = es->hwndListBox;
    HWND hCombo;
    BOOL bDropped;
    int  nEUI;

    if (!hLBox)
        return FALSE;

    hCombo   = GetParent(es->hwndSelf);
    bDropped = TRUE;
    nEUI     = 0;

    TRACE("[%p]: handling msg %x (%x)\n", es->hwndSelf, msg, key);

    if (key == VK_UP || key == VK_DOWN)
    {
        if (SendMessageW(hCombo, CB_GETEXTENDEDUI, 0, 0))
            nEUI = 1;

        if (msg == WM_KEYDOWN || nEUI)
            bDropped = (BOOL)SendMessageW(hCombo, CB_GETDROPPEDSTATE, 0, 0);
    }

    switch (msg)
    {
    case WM_KEYDOWN:
        if (!bDropped && nEUI && (key == VK_UP || key == VK_DOWN))
        {
            /* make sure ComboLBox pops up */
            SendMessageW(hCombo, CB_SETEXTENDEDUI, FALSE, 0);
            key = VK_F4;
            nEUI = 2;
        }

        SendMessageW(hLBox, WM_KEYDOWN, key, 0);
        break;

    case WM_SYSKEYDOWN: /* Handle Alt+up/down arrows */
        if (nEUI)
           SendMessageW(hCombo, CB_SHOWDROPDOWN, !bDropped, 0);
        else
           SendMessageW(hLBox, WM_KEYDOWN, VK_F4, 0);
        break;
    }

    if (nEUI == 2)
        SendMessageW(hCombo, CB_SETEXTENDEDUI, TRUE, 0);

    return TRUE;
}


/*********************************************************************
 *
 *  WM_KEYDOWN
 *
 *  Handling of special keys that don't produce a WM_CHAR
 *  (i.e. non-printable keys) & Backspace & Delete
 *
 */
static LRESULT EDIT_WM_KeyDown(EDITSTATE *es, INT key)
{
    BOOL shift;
    BOOL control;

    if (GetKeyState(VK_MENU) & 0x8000)
        return 0;

    shift = GetKeyState(VK_SHIFT) & 0x8000;
    control = GetKeyState(VK_CONTROL) & 0x8000;

    switch (key) {
    case VK_F4:
    case VK_UP:
        if (EDIT_CheckCombo(es, WM_KEYDOWN, key) || key == VK_F4)
            break;

        /* fall through */
    case VK_LEFT:
        if ((es->style & ES_MULTILINE) && (key == VK_UP))
            EDIT_MoveUp_ML(es, shift);
        else
            if (control)
                EDIT_MoveWordBackward(es, shift);
            else
                EDIT_MoveBackward(es, shift);
        break;
    case VK_DOWN:
        if (EDIT_CheckCombo(es, WM_KEYDOWN, key))
            break;
        /* fall through */
    case VK_RIGHT:
        if ((es->style & ES_MULTILINE) && (key == VK_DOWN))
            EDIT_MoveDown_ML(es, shift);
        else if (control)
            EDIT_MoveWordForward(es, shift);
        else
            EDIT_MoveForward(es, shift);
        break;
    case VK_HOME:
        EDIT_MoveHome(es, shift, control);
        break;
    case VK_END:
        EDIT_MoveEnd(es, shift, control);
        break;
    case VK_PRIOR:
        if (es->style & ES_MULTILINE)
            EDIT_MovePageUp_ML(es, shift);
        else
            EDIT_CheckCombo(es, WM_KEYDOWN, key);
        break;
    case VK_NEXT:
        if (es->style & ES_MULTILINE)
            EDIT_MovePageDown_ML(es, shift);
        else
            EDIT_CheckCombo(es, WM_KEYDOWN, key);
        break;
    case VK_DELETE:
        if (!(es->style & ES_READONLY) && !(shift && control)) {
            if (es->selection_start != es->selection_end) {
                if (shift)
                    EDIT_WM_Cut(es);
                else
                    EDIT_WM_Clear(es);
            } else {
                if (shift) {
                    /* delete character left of caret */
                    EDIT_EM_SetSel(es, (UINT)-1, 0, FALSE);
                    EDIT_MoveBackward(es, TRUE);
                    EDIT_WM_Clear(es);
                } else if (control) {
                    /* delete to end of line */
                    EDIT_EM_SetSel(es, (UINT)-1, 0, FALSE);
                    EDIT_MoveEnd(es, TRUE, FALSE);
                    EDIT_WM_Clear(es);
                } else {
                    /* delete character right of caret */
                    EDIT_EM_SetSel(es, (UINT)-1, 0, FALSE);
                    EDIT_MoveForward(es, TRUE);
                    EDIT_WM_Clear(es);
                }
            }
        }
        break;
    case VK_INSERT:
        if (shift) {
            if (!(es->style & ES_READONLY))
                EDIT_WM_Paste(es);
        } else if (control)
            EDIT_WM_Copy(es);
        break;
    case VK_RETURN:
        /* If the edit doesn't want the return send a message to the default object */
        if(!(es->style & ES_MULTILINE) || !(es->style & ES_WANTRETURN))
        {
                DWORD dw;

                if (!EDIT_IsInsideDialog(es)) break;
                if (control) break;
                dw = SendMessageW(es->hwndParent, DM_GETDEFID, 0, 0);
                if (HIWORD(dw) == DC_HASDEFID)
                {
                    HWND hwDefCtrl = GetDlgItem(es->hwndParent, LOWORD(dw));
                    if (hwDefCtrl)
                    {
                        SendMessageW(es->hwndParent, WM_NEXTDLGCTL, (WPARAM)hwDefCtrl, TRUE);
                        PostMessageW(hwDefCtrl, WM_KEYDOWN, VK_RETURN, 0);
                    }
                }
        }
        break;
        case VK_ESCAPE:
            if ((es->style & ES_MULTILINE) && EDIT_IsInsideDialog(es))
                PostMessageW(es->hwndParent, WM_CLOSE, 0, 0);
            break;
        case VK_TAB:
            if ((es->style & ES_MULTILINE) && EDIT_IsInsideDialog(es))
                SendMessageW(es->hwndParent, WM_NEXTDLGCTL, shift, 0);
            break;
        case 'A':
            if (control)
            {
                if (EDIT_EM_SetSel(es, 0, get_text_length(es), FALSE))
                {
                    EDIT_NOTIFY_PARENT(es, EN_UPDATE);
                    EDIT_NOTIFY_PARENT(es, EN_CHANGE);
                }
            }
            break;
    }
        return TRUE;
}


/*********************************************************************
 *
 *  WM_KILLFOCUS
 *
 */
static LRESULT EDIT_WM_KillFocus(HTHEME theme, EDITSTATE *es)
{
    UINT flags = RDW_INVALIDATE | RDW_UPDATENOW;

    es->flags &= ~EF_FOCUSED;
    DestroyCaret();
    if (!(es->style & ES_NOHIDESEL))
        EDIT_InvalidateText(es, es->selection_start, es->selection_end);
    EDIT_NOTIFY_PARENT(es, EN_KILLFOCUS);
    /* Throw away left over scroll when we lose focus */
    es->wheelDeltaRemainder = 0;

    if (theme)
        flags |= RDW_FRAME;

    RedrawWindow(es->hwndSelf, NULL, NULL, flags);
    return 0;
}


/*********************************************************************
 *
 *  WM_LBUTTONDBLCLK
 *
 *  The caret position has been set on the WM_LBUTTONDOWN message
 *
 */
static LRESULT EDIT_WM_LButtonDblClk(EDITSTATE *es)
{
    INT s;
    INT e = es->selection_end;
    INT l;
    INT li;
    INT ll;

    es->bCaptureState = TRUE;
    SetCapture(es->hwndSelf);

    l = EDIT_EM_LineFromChar(es, e);
    li = EDIT_EM_LineIndex(es, l);
    ll = EDIT_EM_LineLength(es, e);
    s = li + EDIT_CallWordBreakProc(es, li, e - li, ll, WB_LEFT);
    e = li + EDIT_CallWordBreakProc(es, li, e - li, ll, WB_RIGHT);
    EDIT_EM_SetSel(es, s, e, FALSE);
    EDIT_EM_ScrollCaret(es);
    es->region_posx = es->region_posy = 0;
    SetTimer(es->hwndSelf, 0, 100, NULL);
    return 0;
}


/*********************************************************************
 *
 *  WM_LBUTTONDOWN
 *
 */
static LRESULT EDIT_WM_LButtonDown(EDITSTATE *es, DWORD keys, INT x, INT y)
{
    INT e;
    BOOL after_wrap;

    es->bCaptureState = TRUE;
    SetCapture(es->hwndSelf);
    EDIT_ConfinePoint(es, &x, &y);
    e = EDIT_CharFromPos(es, x, y, &after_wrap);
    EDIT_EM_SetSel(es, (keys & MK_SHIFT) ? es->selection_start : e, e, after_wrap);
    EDIT_EM_ScrollCaret(es);
    es->region_posx = es->region_posy = 0;
    SetTimer(es->hwndSelf, 0, 100, NULL);

    if (!(es->flags & EF_FOCUSED))
            SetFocus(es->hwndSelf);

    return 0;
}


/*********************************************************************
 *
 *  WM_LBUTTONUP
 *
 */
static LRESULT EDIT_WM_LButtonUp(EDITSTATE *es)
{
    if (es->bCaptureState) {
        KillTimer(es->hwndSelf, 0);
        if (GetCapture() == es->hwndSelf) ReleaseCapture();
    }
    es->bCaptureState = FALSE;
    return 0;
}


/*********************************************************************
 *
 *  WM_MBUTTONDOWN
 *
 */
static LRESULT EDIT_WM_MButtonDown(EDITSTATE *es)
{
    SendMessageW(es->hwndSelf, WM_PASTE, 0, 0);
    return 0;
}


/*********************************************************************
 *
 *  WM_MOUSEMOVE
 *
 */
static LRESULT EDIT_WM_MouseMove(EDITSTATE *es, INT x, INT y)
{
    INT e;
    BOOL after_wrap;
    INT prex, prey;

        /* If the mouse has been captured by process other than the edit control itself,
         * the windows edit controls will not select the strings with mouse move.
         */
        if (!es->bCaptureState || GetCapture() != es->hwndSelf)
        return 0;

    /*
     *  FIXME: gotta do some scrolling if outside client
     *      area.  Maybe reset the timer ?
     */
    prex = x; prey = y;
    EDIT_ConfinePoint(es, &x, &y);
    es->region_posx = (prex < x) ? -1 : ((prex > x) ? 1 : 0);
    es->region_posy = (prey < y) ? -1 : ((prey > y) ? 1 : 0);
    e = EDIT_CharFromPos(es, x, y, &after_wrap);
    EDIT_EM_SetSel(es, es->selection_start, e, after_wrap);
    EDIT_SetCaretPos(es,es->selection_end,es->flags & EF_AFTER_WRAP);
    return 0;
}


/*********************************************************************
 *
 *  WM_PAINT
 *
 */
static void EDIT_WM_Paint(EDITSTATE *es, HDC hdc)
{
    PAINTSTRUCT ps;
    INT i;
    HDC dc;
    HFONT old_font = 0;
    RECT rc;
    RECT rcClient;
    RECT rcLine;
    RECT rcRgn;
    HBRUSH brush;
    HBRUSH old_brush;
    INT bw, bh;
    BOOL rev = es->bEnableState &&
                ((es->flags & EF_FOCUSED) ||
                    (es->style & ES_NOHIDESEL));
        dc = hdc ? hdc : BeginPaint(es->hwndSelf, &ps);

    /* The dc we use for calculating may not be the one we paint into.
       This is the safest action. */
    EDIT_InvalidateUniscribeData(es);
    GetClientRect(es->hwndSelf, &rcClient);

    /* get the background brush */
    brush = EDIT_NotifyCtlColor(es, dc);

    /* paint the border and the background */
    IntersectClipRect(dc, rcClient.left, rcClient.top, rcClient.right, rcClient.bottom);

    if(es->style & WS_BORDER) {
        bw = GetSystemMetrics(SM_CXBORDER);
        bh = GetSystemMetrics(SM_CYBORDER);
        rc = rcClient;
        if(es->style & ES_MULTILINE) {
            if(es->style & WS_HSCROLL) rc.bottom+=bh;
            if(es->style & WS_VSCROLL) rc.right+=bw;
        }

        /* Draw the frame. Same code as in nonclient.c */
        old_brush = SelectObject(dc, GetSysColorBrush(COLOR_WINDOWFRAME));
        PatBlt(dc, rc.left, rc.top, rc.right - rc.left, bh, PATCOPY);
        PatBlt(dc, rc.left, rc.top, bw, rc.bottom - rc.top, PATCOPY);
        PatBlt(dc, rc.left, rc.bottom - 1, rc.right - rc.left, -bw, PATCOPY);
        PatBlt(dc, rc.right - 1, rc.top, -bw, rc.bottom - rc.top, PATCOPY);
        SelectObject(dc, old_brush);

        /* Keep the border clean */
        IntersectClipRect(dc, rc.left+bw, rc.top+bh,
            max(rc.right-bw, rc.left+bw), max(rc.bottom-bh, rc.top+bh));
    }

    GetClipBox(dc, &rc);
    FillRect(dc, &rc, brush);

    IntersectClipRect(dc, es->format_rect.left,
                es->format_rect.top,
                es->format_rect.right,
                es->format_rect.bottom);
    if (es->style & ES_MULTILINE) {
        rc = rcClient;
        IntersectClipRect(dc, rc.left, rc.top, rc.right, rc.bottom);
    }
    if (es->font)
        old_font = SelectObject(dc, es->font);

    if (!es->bEnableState)
        SetTextColor(dc, GetSysColor(COLOR_GRAYTEXT));
    GetClipBox(dc, &rcRgn);
    if (es->style & ES_MULTILINE) {
        INT vlc = get_vertical_line_count(es);
        for (i = es->y_offset ; i <= min(es->y_offset + vlc, es->y_offset + es->line_count - 1) ; i++) {
            EDIT_UpdateUniscribeData(es, dc, i);
            EDIT_GetLineRect(es, i, 0, -1, &rcLine);
            if (IntersectRect(&rc, &rcRgn, &rcLine))
                EDIT_PaintLine(es, dc, i, rev);
        }
    } else {
        EDIT_UpdateUniscribeData(es, dc, 0);
        EDIT_GetLineRect(es, 0, 0, -1, &rcLine);
        if (IntersectRect(&rc, &rcRgn, &rcLine))
            EDIT_PaintLine(es, dc, 0, rev);
    }
    if (es->font)
        SelectObject(dc, old_font);

        if (!hdc)
            EndPaint(es->hwndSelf, &ps);
}

static void EDIT_WM_NCPaint(HWND hwnd, HRGN region)
{
    DWORD exStyle = GetWindowLongW(hwnd, GWL_EXSTYLE);
    HTHEME theme = GetWindowTheme(hwnd);
    HRGN cliprgn = region;

    if (theme && exStyle & WS_EX_CLIENTEDGE)
    {
        HDC dc;
        RECT r;
        int cxEdge = GetSystemMetrics(SM_CXEDGE),
            cyEdge = GetSystemMetrics(SM_CYEDGE);
        const int part = EP_EDITTEXT;
        int state = ETS_NORMAL;
        DWORD dwStyle = GetWindowLongW(hwnd, GWL_STYLE);

        if (!IsWindowEnabled(hwnd))
            state = ETS_DISABLED;
        else if (dwStyle & ES_READONLY)
            state = ETS_READONLY;
        else if (GetFocus() == hwnd)
            state = ETS_FOCUSED;

        GetWindowRect(hwnd, &r);

        /* New clipping region passed to default proc to exclude border */
        cliprgn = CreateRectRgn(r.left + cxEdge, r.top + cyEdge,
            r.right - cxEdge, r.bottom - cyEdge);
        if (region != (HRGN)1)
            CombineRgn(cliprgn, cliprgn, region, RGN_AND);
        OffsetRect(&r, -r.left, -r.top);

#ifdef __REACTOS__ /* r73789 */
        dc = GetWindowDC(hwnd);
        /* Exclude client part */
        ExcludeClipRect(dc,
                        r.left + cxEdge,
                        r.top + cyEdge,
                        r.right - cxEdge,
                        r.bottom -cyEdge);
#else
        dc = GetDCEx(hwnd, region, DCX_WINDOW|DCX_INTERSECTRGN);
        OffsetRect(&r, -r.left, -r.top);
#endif

        if (IsThemeBackgroundPartiallyTransparent(theme, part, state))
            DrawThemeParentBackground(hwnd, dc, &r);
        DrawThemeBackground(theme, dc, part, state, &r, 0);
        ReleaseDC(hwnd, dc);
    }

    /* Call default proc to get the scrollbars etc. also painted */
    DefWindowProcW (hwnd, WM_NCPAINT, (WPARAM)cliprgn, 0);
}

/*********************************************************************
 *
 *  WM_SETFOCUS
 *
 */
static void EDIT_WM_SetFocus(HTHEME theme, EDITSTATE *es)
{
    UINT flags = RDW_INVALIDATE | RDW_UPDATENOW;

    es->flags |= EF_FOCUSED;

    if (!(es->style & ES_NOHIDESEL))
        EDIT_InvalidateText(es, es->selection_start, es->selection_end);

    CreateCaret(es->hwndSelf, 0, 1, es->line_height);
    EDIT_SetCaretPos(es, es->selection_end, es->flags & EF_AFTER_WRAP);
    ShowCaret(es->hwndSelf);
    EDIT_NOTIFY_PARENT(es, EN_SETFOCUS);

    if (theme)
        flags |= RDW_FRAME | RDW_ERASE;

    RedrawWindow(es->hwndSelf, NULL, NULL, flags);
}


/*********************************************************************
 *
 *  WM_SETFONT
 *
 * With Win95 look the margins are set to default font value unless
 * the system font (font == 0) is being set, in which case they are left
 * unchanged.
 *
 */
static void EDIT_WM_SetFont(EDITSTATE *es, HFONT font, BOOL redraw)
{
    TEXTMETRICW tm;
    HDC dc;
    HFONT old_font = 0;
    RECT clientRect;

    es->font = font;
    EDIT_InvalidateUniscribeData(es);
    dc = GetDC(es->hwndSelf);
    if (font)
        old_font = SelectObject(dc, font);
    GetTextMetricsW(dc, &tm);
    es->line_height = tm.tmHeight;
    es->char_width = tm.tmAveCharWidth;
    if (font)
        SelectObject(dc, old_font);
    ReleaseDC(es->hwndSelf, dc);

    /* Reset the format rect and the margins */
    GetClientRect(es->hwndSelf, &clientRect);
    EDIT_SetRectNP(es, &clientRect);
    EDIT_EM_SetMargins(es, EC_LEFTMARGIN | EC_RIGHTMARGIN,
               EC_USEFONTINFO, EC_USEFONTINFO, FALSE);

    if (es->style & ES_MULTILINE)
        EDIT_BuildLineDefs_ML(es, 0, get_text_length(es), 0, NULL);
    else
        EDIT_CalcLineWidth_SL(es);

    if (redraw)
        EDIT_UpdateText(es, NULL, TRUE);
    if (es->flags & EF_FOCUSED) {
        DestroyCaret();
        CreateCaret(es->hwndSelf, 0, 1, es->line_height);
        EDIT_SetCaretPos(es, es->selection_end,
                 es->flags & EF_AFTER_WRAP);
        ShowCaret(es->hwndSelf);
    }
}


/*********************************************************************
 *
 *  WM_SETTEXT
 *
 * NOTES
 *  For multiline controls (ES_MULTILINE), reception of WM_SETTEXT triggers:
 *  The modified flag is reset. No notifications are sent.
 *
 *  For single-line controls, reception of WM_SETTEXT triggers:
 *  The modified flag is reset. EN_UPDATE and EN_CHANGE notifications are sent.
 *
 */
static void EDIT_WM_SetText(EDITSTATE *es, LPCWSTR text)
{
    if (es->flags & EF_UPDATE)
        /* fixed this bug once; complain if we see it about to happen again. */
        ERR("SetSel may generate UPDATE message whose handler may reset "
            "selection.\n");

    EDIT_EM_SetSel(es, 0, (UINT)-1, FALSE);
    if (text)
    {
    TRACE("%s\n", debugstr_w(text));
    EDIT_EM_ReplaceSel(es, FALSE, text, strlenW(text), FALSE, FALSE);
    }
    else
    {
    TRACE("<NULL>\n");
    EDIT_EM_ReplaceSel(es, FALSE, NULL, 0, FALSE, FALSE);
    }
    es->x_offset = 0;
    es->flags &= ~EF_MODIFIED;
    EDIT_EM_SetSel(es, 0, 0, FALSE);

    /* Send the notification after the selection start and end have been set
     * edit control doesn't send notification on WM_SETTEXT
     * if it is multiline, or it is part of combobox
     */
    if( !((es->style & ES_MULTILINE) || es->hwndListBox))
    {
        EDIT_NOTIFY_PARENT(es, EN_UPDATE);
        EDIT_NOTIFY_PARENT(es, EN_CHANGE);
    }
    EDIT_EM_ScrollCaret(es);
    EDIT_UpdateScrollInfo(es);
    EDIT_InvalidateUniscribeData(es);
}


/*********************************************************************
 *
 *  WM_SIZE
 *
 */
static void EDIT_WM_Size(EDITSTATE *es, UINT action)
{
    if ((action == SIZE_MAXIMIZED) || (action == SIZE_RESTORED)) {
        RECT rc;
        GetClientRect(es->hwndSelf, &rc);
        EDIT_SetRectNP(es, &rc);
        EDIT_UpdateText(es, NULL, TRUE);
    }
}


/*********************************************************************
 *
 *  WM_STYLECHANGED
 *
 * This message is sent by SetWindowLong on having changed either the Style
 * or the extended style.
 *
 * We ensure that the window's version of the styles and the EDITSTATE's agree.
 *
 * See also EDIT_WM_NCCreate
 *
 * It appears that the Windows version of the edit control allows the style
 * (as retrieved by GetWindowLong) to be any value and maintains an internal
 * style variable which will generally be different.  In this function we
 * update the internal style based on what changed in the externally visible
 * style.
 *
 * Much of this content as based upon the MSDN, especially:
 *  Platform SDK Documentation -> User Interface Services ->
 *      Windows User Interface -> Edit Controls -> Edit Control Reference ->
 *      Edit Control Styles
 */
static LRESULT  EDIT_WM_StyleChanged ( EDITSTATE *es, WPARAM which, const STYLESTRUCT *style)
{
        if (GWL_STYLE == which) {
                DWORD style_change_mask;
                DWORD new_style;
                /* Only a subset of changes can be applied after the control
                 * has been created.
                 */
                style_change_mask = ES_UPPERCASE | ES_LOWERCASE |
                                    ES_NUMBER;
                if (es->style & ES_MULTILINE)
                        style_change_mask |= ES_WANTRETURN;

                new_style = style->styleNew & style_change_mask;

                /* Number overrides lowercase overrides uppercase (at least it
                 * does in Win95).  However I'll bet that ES_NUMBER would be
                 * invalid under Win 3.1.
                 */
                if (new_style & ES_NUMBER) {
                        ; /* do not override the ES_NUMBER */
                }  else if (new_style & ES_LOWERCASE) {
                        new_style &= ~ES_UPPERCASE;
                }

                es->style = (es->style & ~style_change_mask) | new_style;
        } else if (GWL_EXSTYLE == which) {
                ; /* FIXME - what is needed here */
        } else {
                WARN ("Invalid style change %ld\n",which);
        }

        return 0;
}

/*********************************************************************
 *
 *  WM_SYSKEYDOWN
 *
 */
static LRESULT EDIT_WM_SysKeyDown(EDITSTATE *es, INT key, DWORD key_data)
{
    if ((key == VK_BACK) && (key_data & 0x2000)) {
        if (EDIT_EM_CanUndo(es))
            EDIT_EM_Undo(es);
        return 0;
    } else if (key == VK_UP || key == VK_DOWN) {
        if (EDIT_CheckCombo(es, WM_SYSKEYDOWN, key))
            return 0;
    }
    return DefWindowProcW(es->hwndSelf, WM_SYSKEYDOWN, key, key_data);
}


/*********************************************************************
 *
 *  WM_TIMER
 *
 */
static void EDIT_WM_Timer(EDITSTATE *es)
{
    if (es->region_posx < 0) {
        EDIT_MoveBackward(es, TRUE);
    } else if (es->region_posx > 0) {
        EDIT_MoveForward(es, TRUE);
    }
/*
 *  FIXME: gotta do some vertical scrolling here, like
 *      EDIT_EM_LineScroll(hwnd, 0, 1);
 */
}

/*********************************************************************
 *
 *  WM_HSCROLL
 *
 */
static LRESULT EDIT_WM_HScroll(EDITSTATE *es, INT action, INT pos)
{
    INT dx;
    INT fw;

    if (!(es->style & ES_MULTILINE))
        return 0;

    if (!(es->style & ES_AUTOHSCROLL))
        return 0;

    dx = 0;
    fw = es->format_rect.right - es->format_rect.left;
    switch (action) {
    case SB_LINELEFT:
        TRACE("SB_LINELEFT\n");
        if (es->x_offset)
            dx = -es->char_width;
        break;
    case SB_LINERIGHT:
        TRACE("SB_LINERIGHT\n");
        if (es->x_offset < es->text_width)
            dx = es->char_width;
        break;
    case SB_PAGELEFT:
        TRACE("SB_PAGELEFT\n");
        if (es->x_offset)
            dx = -fw / HSCROLL_FRACTION / es->char_width * es->char_width;
        break;
    case SB_PAGERIGHT:
        TRACE("SB_PAGERIGHT\n");
        if (es->x_offset < es->text_width)
            dx = fw / HSCROLL_FRACTION / es->char_width * es->char_width;
        break;
    case SB_LEFT:
        TRACE("SB_LEFT\n");
        if (es->x_offset)
            dx = -es->x_offset;
        break;
    case SB_RIGHT:
        TRACE("SB_RIGHT\n");
        if (es->x_offset < es->text_width)
            dx = es->text_width - es->x_offset;
        break;
    case SB_THUMBTRACK:
        TRACE("SB_THUMBTRACK %d\n", pos);
        es->flags |= EF_HSCROLL_TRACK;
        if(es->style & WS_HSCROLL)
            dx = pos - es->x_offset;
        else
        {
            INT fw, new_x;
            /* Sanity check */
            if(pos < 0 || pos > 100) return 0;
            /* Assume default scroll range 0-100 */
            fw = es->format_rect.right - es->format_rect.left;
            new_x = pos * (es->text_width - fw) / 100;
            dx = es->text_width ? (new_x - es->x_offset) : 0;
        }
        break;
    case SB_THUMBPOSITION:
        TRACE("SB_THUMBPOSITION %d\n", pos);
        es->flags &= ~EF_HSCROLL_TRACK;
        if(GetWindowLongW( es->hwndSelf, GWL_STYLE ) & WS_HSCROLL)
            dx = pos - es->x_offset;
        else
        {
            INT fw, new_x;
            /* Sanity check */
            if(pos < 0 || pos > 100) return 0;
            /* Assume default scroll range 0-100 */
            fw = es->format_rect.right - es->format_rect.left;
            new_x = pos * (es->text_width - fw) / 100;
            dx = es->text_width ? (new_x - es->x_offset) : 0;
        }
        if (!dx) {
            /* force scroll info update */
            EDIT_UpdateScrollInfo(es);
            EDIT_NOTIFY_PARENT(es, EN_HSCROLL);
        }
        break;
    case SB_ENDSCROLL:
        TRACE("SB_ENDSCROLL\n");
        break;
    /*
     *  FIXME : the next two are undocumented !
     *  Are we doing the right thing ?
     *  At least Win 3.1 Notepad makes use of EM_GETTHUMB this way,
     *  although it's also a regular control message.
     */
    case EM_GETTHUMB: /* this one is used by NT notepad */
    {
        LRESULT ret;
        if(GetWindowLongW( es->hwndSelf, GWL_STYLE ) & WS_HSCROLL)
            ret = GetScrollPos(es->hwndSelf, SB_HORZ);
        else
        {
            /* Assume default scroll range 0-100 */
            INT fw = es->format_rect.right - es->format_rect.left;
            ret = es->text_width ? es->x_offset * 100 / (es->text_width - fw) : 0;
        }
        TRACE("EM_GETTHUMB: returning %ld\n", ret);
        return ret;
    }
    case EM_LINESCROLL:
        TRACE("EM_LINESCROLL16\n");
        dx = pos;
        break;

    default:
        ERR("undocumented WM_HSCROLL action %d (0x%04x), please report\n",
                    action, action);
        return 0;
    }
    if (dx)
    {
        INT fw = es->format_rect.right - es->format_rect.left;
        /* check if we are going to move too far */
        if(es->x_offset + dx + fw > es->text_width)
        dx = es->text_width - fw - es->x_offset;
        if(dx)
        EDIT_EM_LineScroll_internal(es, dx, 0);
    }
    return 0;
}


/*********************************************************************
 *
 *  WM_VSCROLL
 *
 */
static LRESULT EDIT_WM_VScroll(EDITSTATE *es, INT action, INT pos)
{
    INT dy;

    if (!(es->style & ES_MULTILINE))
        return 0;

    if (!(es->style & ES_AUTOVSCROLL))
        return 0;

    dy = 0;
    switch (action) {
    case SB_LINEUP:
    case SB_LINEDOWN:
    case SB_PAGEUP:
    case SB_PAGEDOWN:
        TRACE("action %d (%s)\n", action, (action == SB_LINEUP ? "SB_LINEUP" :
                           (action == SB_LINEDOWN ? "SB_LINEDOWN" :
                            (action == SB_PAGEUP ? "SB_PAGEUP" :
                             "SB_PAGEDOWN"))));
        EDIT_EM_Scroll(es, action);
        return 0;
    case SB_TOP:
        TRACE("SB_TOP\n");
        dy = -es->y_offset;
        break;
    case SB_BOTTOM:
        TRACE("SB_BOTTOM\n");
        dy = es->line_count - 1 - es->y_offset;
        break;
    case SB_THUMBTRACK:
        TRACE("SB_THUMBTRACK %d\n", pos);
        es->flags |= EF_VSCROLL_TRACK;
        if(es->style & WS_VSCROLL)
            dy = pos - es->y_offset;
        else
        {
            /* Assume default scroll range 0-100 */
            INT vlc, new_y;
            /* Sanity check */
            if(pos < 0 || pos > 100) return 0;
            vlc = get_vertical_line_count(es);
            new_y = pos * (es->line_count - vlc) / 100;
            dy = es->line_count ? (new_y - es->y_offset) : 0;
            TRACE("line_count=%d, y_offset=%d, pos=%d, dy = %d\n",
                es->line_count, es->y_offset, pos, dy);
        }
        break;
    case SB_THUMBPOSITION:
        TRACE("SB_THUMBPOSITION %d\n", pos);
        es->flags &= ~EF_VSCROLL_TRACK;
        if(es->style & WS_VSCROLL)
            dy = pos - es->y_offset;
        else
        {
            /* Assume default scroll range 0-100 */
            INT vlc, new_y;
            /* Sanity check */
            if(pos < 0 || pos > 100) return 0;
            vlc = get_vertical_line_count(es);
            new_y = pos * (es->line_count - vlc) / 100;
            dy = es->line_count ? (new_y - es->y_offset) : 0;
            TRACE("line_count=%d, y_offset=%d, pos=%d, dy = %d\n",
                es->line_count, es->y_offset, pos, dy);
        }
        if (!dy)
        {
            /* force scroll info update */
            EDIT_UpdateScrollInfo(es);
            EDIT_NOTIFY_PARENT(es, EN_VSCROLL);
        }
        break;
    case SB_ENDSCROLL:
        TRACE("SB_ENDSCROLL\n");
        break;
    /*
     *  FIXME : the next two are undocumented !
     *  Are we doing the right thing ?
     *  At least Win 3.1 Notepad makes use of EM_GETTHUMB this way,
     *  although it's also a regular control message.
     */
    case EM_GETTHUMB: /* this one is used by NT notepad */
    {
        LRESULT ret;
        if(GetWindowLongW( es->hwndSelf, GWL_STYLE ) & WS_VSCROLL)
            ret = GetScrollPos(es->hwndSelf, SB_VERT);
        else
        {
            /* Assume default scroll range 0-100 */
            INT vlc = get_vertical_line_count(es);
            ret = es->line_count ? es->y_offset * 100 / (es->line_count - vlc) : 0;
        }
        TRACE("EM_GETTHUMB: returning %ld\n", ret);
        return ret;
    }
    case EM_LINESCROLL:
        TRACE("EM_LINESCROLL %d\n", pos);
        dy = pos;
        break;

    default:
        ERR("undocumented WM_VSCROLL action %d (0x%04x), please report\n",
                    action, action);
        return 0;
    }
    if (dy)
        EDIT_EM_LineScroll(es, 0, dy);
    return 0;
}

/*********************************************************************
 *
 *  EM_GETTHUMB
 *
 *  FIXME: is this right ?  (or should it be only VSCROLL)
 *  (and maybe only for edit controls that really have their
 *  own scrollbars) (and maybe only for multiline controls ?)
 *  All in all: very poorly documented
 *
 */
static LRESULT EDIT_EM_GetThumb(EDITSTATE *es)
{
    return MAKELONG(EDIT_WM_VScroll(es, EM_GETTHUMB, 0),
                        EDIT_WM_HScroll(es, EM_GETTHUMB, 0));
}


/********************************************************************
 *
 * The Following code is to handle inline editing from IMEs
 */

static void EDIT_GetCompositionStr(HIMC hIMC, LPARAM