caret.c

winNT技术操作系统,国外开放的原代码和LIUX一样

  ME_DisplayItem *pLast, *p;
  int x, y, ys, yd, yp, yprev;
  ME_Cursor tmp_curs = *pCursor;
  
  x = ME_GetXForArrow(editor, pCursor);
  if (!pCursor->nOffset && editor->bCaretAtEnd)
    pRun = ME_FindItemBack(pRun, diRun);
  
  p = ME_FindItemBack(pRun, diStartRowOrParagraph);
  assert(p->type == diStartRow);
  yp = ME_FindItemBack(p, diParagraph)->member.para.nYPos;
  yprev = ys = y = yp + p->member.row.nYPos;
  yd = y - editor->sizeWindow.cy;
  pLast = p;
  
  do {
    p = ME_FindItemBack(p, diStartRowOrParagraph);
    if (!p)
      break;
    if (p->type == diParagraph) { /* crossing paragraphs */
      if (p->member.para.prev_para == NULL)
        break;
      yp = p->member.para.prev_para->member.para.nYPos;
      continue;
    }
    y = yp + p->member.row.nYPos;
    if (y < yd)
      break;
    pLast = p;
    yprev = y;
  } while(1);
  
  pCursor->pRun = ME_FindRunInRow(editor, pLast, x, &pCursor->nOffset, &editor->bCaretAtEnd);
  ME_UpdateSelection(editor, &tmp_curs);
  if (yprev < editor->sizeWindow.cy)
  {
    ME_EnsureVisible(editor, ME_FindItemFwd(editor->pBuffer->pFirst, diRun));
    ME_Repaint(editor);
  }
  else {
    ME_Scroll(editor, 0, ys-yprev);
    ME_Repaint(editor);
  }
  assert(pCursor->pRun);
  assert(pCursor->pRun->type == diRun);
}

/* FIXME: in the original RICHEDIT, PageDown always scrolls by the same amount 
   of pixels, even if it makes the scroll bar position exceed its normal maximum.
   In such a situation, clicking the scrollbar restores its position back to the
   normal range (ie. sets it to (doclength-screenheight)). */

static void ME_ArrowPageDown(ME_TextEditor *editor, ME_Cursor *pCursor)
{
  ME_DisplayItem *pRun = pCursor->pRun;
  ME_DisplayItem *pLast, *p;
  int x, y, ys, yd, yp, yprev;
  ME_Cursor tmp_curs = *pCursor;
  
  x = ME_GetXForArrow(editor, pCursor);
  if (!pCursor->nOffset && editor->bCaretAtEnd)
    pRun = ME_FindItemBack(pRun, diRun);
  
  p = ME_FindItemBack(pRun, diStartRowOrParagraph);
  assert(p->type == diStartRow);
  yp = ME_FindItemBack(p, diParagraph)->member.para.nYPos;
  yprev = ys = y = yp + p->member.row.nYPos;
  yd = y + editor->sizeWindow.cy;
  pLast = p;
  
  do {
    p = ME_FindItemFwd(p, diStartRowOrParagraph);
    if (!p)
      break;
    if (p->type == diParagraph) {
      yp = p->member.para.nYPos;
      continue;
    }
    y = yp + p->member.row.nYPos;
    if (y >= yd)
      break;
    pLast = p;
    yprev = y;
  } while(1);
  
  pCursor->pRun = ME_FindRunInRow(editor, pLast, x, &pCursor->nOffset, &editor->bCaretAtEnd);
  ME_UpdateSelection(editor, &tmp_curs);
  if (yprev >= editor->nTotalLength-editor->sizeWindow.cy)
  {
    ME_EnsureVisible(editor, ME_FindItemBack(editor->pBuffer->pLast, diRun));
    ME_Repaint(editor);
  }
  else {
    ME_Scroll(editor, 0, ys-yprev);
    ME_Repaint(editor);
  }
  assert(pCursor->pRun);
  assert(pCursor->pRun->type == diRun);
}

static void ME_ArrowHome(ME_TextEditor *editor, ME_Cursor *pCursor)
{
  ME_DisplayItem *pRow = ME_FindItemBack(pCursor->pRun, diStartRow);
  if (pRow) {
    ME_DisplayItem *pRun;
    if (editor->bCaretAtEnd && !pCursor->nOffset) {
      pRow = ME_FindItemBack(pRow, diStartRow);
      if (!pRow)
        return;
    }
    pRun = ME_FindItemFwd(pRow, diRun);
    if (pRun) {
      pCursor->pRun = pRun;
      pCursor->nOffset = 0;
    }
  }
  editor->bCaretAtEnd = FALSE;
}

static void ME_ArrowCtrlHome(ME_TextEditor *editor, ME_Cursor *pCursor)
{
  ME_DisplayItem *pRow = ME_FindItemBack(pCursor->pRun, diTextStart);
  if (pRow) {
    ME_DisplayItem *pRun = ME_FindItemFwd(pRow, diRun);
    if (pRun) {
      pCursor->pRun = pRun;
      pCursor->nOffset = 0;
    }
  }
}

static void ME_ArrowEnd(ME_TextEditor *editor, ME_Cursor *pCursor)
{
  ME_DisplayItem *pRow;
  
  if (editor->bCaretAtEnd && !pCursor->nOffset)
    return;
  
  pRow = ME_FindItemFwd(pCursor->pRun, diStartRowOrParagraphOrEnd);
  assert(pRow);
  if (pRow->type == diStartRow) {
    /* FIXME WTF was I thinking about here ? */
    ME_DisplayItem *pRun = ME_FindItemFwd(pRow, diRun);
    assert(pRun);
    pCursor->pRun = pRun;
    pCursor->nOffset = 0;
    editor->bCaretAtEnd = 1;
    return;
  }
  pCursor->pRun = ME_FindItemBack(pRow, diRun);
  assert(pCursor->pRun && pCursor->pRun->member.run.nFlags & MERF_ENDPARA);
  pCursor->nOffset = 0;
  editor->bCaretAtEnd = FALSE;
}
      
static void ME_ArrowCtrlEnd(ME_TextEditor *editor, ME_Cursor *pCursor)
{
  ME_DisplayItem *p = ME_FindItemFwd(pCursor->pRun, diTextEnd);
  assert(p);
  p = ME_FindItemBack(p, diRun);
  assert(p);
  assert(p->member.run.nFlags & MERF_ENDPARA);
  pCursor->pRun = p;
  pCursor->nOffset = 0;
  editor->bCaretAtEnd = FALSE;
}

BOOL ME_IsSelection(ME_TextEditor *editor)
{
  return memcmp(&editor->pCursors[0], &editor->pCursors[1], sizeof(ME_Cursor))!=0;
}

static int ME_GetSelCursor(ME_TextEditor *editor, int dir)
{
  int cdir = ME_GetCursorOfs(editor, 0) - ME_GetCursorOfs(editor, 1);
  
  if (cdir*dir>0)
    return 0;
  else
    return 1;
}
      
static BOOL ME_CancelSelection(ME_TextEditor *editor, int dir)
{
  int cdir;
  
  if (GetKeyState(VK_SHIFT)<0)
    return FALSE;
  if (!memcmp(&editor->pCursors[0], &editor->pCursors[1], sizeof(ME_Cursor)))
    return FALSE;
  
  cdir = ME_GetCursorOfs(editor, 0) - ME_GetCursorOfs(editor, 1);
  
  if (cdir*dir>0)
    editor->pCursors[1] = editor->pCursors[0];
  else
    editor->pCursors[0] = editor->pCursors[1];
  ME_Repaint(editor);
  return TRUE;
}

BOOL ME_UpdateSelection(ME_TextEditor *editor, ME_Cursor *pTempCursor)
{
  ME_Cursor old_anchor = editor->pCursors[1];
  
  if (GetKeyState(VK_SHIFT)>=0) /* cancelling selection */
  {
    /* any selection was present ? if so, it's no more, repaint ! */
    editor->pCursors[1] = editor->pCursors[0];
    if (memcmp(pTempCursor, &old_anchor, sizeof(ME_Cursor))) {
      return TRUE;
    }
    return FALSE;
  }
  else
  {
    if (!memcmp(pTempCursor, &editor->pCursors[1], sizeof(ME_Cursor))) /* starting selection */
    {
      editor->pCursors[1] = *pTempCursor;
      return TRUE;
    }
  }

  ME_Repaint(editor);
  return TRUE;
}

static void ME_RepaintSelection(ME_TextEditor *editor, ME_Cursor *pTempCursor)
{
  if (ME_UpdateSelection(editor, pTempCursor)) {
    ME_EnsureVisible(editor, editor->pCursors[0].pRun); 
    ME_Repaint(editor);
  }
}

void ME_DeleteSelection(ME_TextEditor *editor)
{
  int from, to;
  ME_GetSelection(editor, &from, &to);
  ME_DeleteTextAtCursor(editor, ME_GetSelCursor(editor,-1), to-from);
}

ME_Style *ME_GetSelectionInsertStyle(ME_TextEditor *editor)
{
  ME_Style *style;
  int from, to;
  ME_Cursor c;
  
  ME_GetSelection(editor, &from, &to);
  ME_CursorFromCharOfs(editor, from, &c);
  if (from != to) {
    style = c.pRun->member.run.style;
    ME_AddRefStyle(style); /* ME_GetInsertStyle has already done that */
  }
  else
    style = ME_GetInsertStyle(editor, 0);
  return style;
}

void ME_SendSelChange(ME_TextEditor *editor)
{
  SELCHANGE sc;
  if (!(editor->nEventMask & ENM_SELCHANGE))
    return;
  sc.nmhdr.hwndFrom = editor->hWnd;
  sc.nmhdr.idFrom = GetWindowLongW(editor->hWnd, GWLP_ID);
  sc.nmhdr.code = EN_SELCHANGE;
  SendMessageW(editor->hWnd, EM_EXGETSEL, 0, (LPARAM)&sc.chrg);
  sc.seltyp = SEL_EMPTY;
  if (sc.chrg.cpMin != sc.chrg.cpMax)
    sc.seltyp |= SEL_TEXT;
  if (sc.chrg.cpMin < sc.chrg.cpMax+1) /* wth were RICHEDIT authors thinking ? */
    sc.seltyp |= SEL_MULTICHAR;
  SendMessageW(GetParent(editor->hWnd), WM_NOTIFY, sc.nmhdr.idFrom, (LPARAM)&sc);
}

BOOL ME_ArrowKey(ME_TextEditor *editor, int nVKey, int nCtrl)
{
  int nCursor = 0;
  ME_Cursor *p = &editor->pCursors[nCursor];
  ME_Cursor tmp_curs = *p;
  
  switch(nVKey) {
    case VK_UP:
      ME_ArrowUp(editor, p);
      ME_ClearTempStyle(editor);
      ME_RepaintSelection(editor, &tmp_curs);
      ME_SendSelChange(editor);
      return TRUE;
    case VK_DOWN:
      ME_ArrowDown(editor, p);
      ME_ClearTempStyle(editor);
      ME_RepaintSelection(editor, &tmp_curs);
      ME_SendSelChange(editor);
      return TRUE;
    case VK_PRIOR:
      ME_ArrowPageUp(editor, p);
      ME_ClearTempStyle(editor);
      ME_SendSelChange(editor);
      return TRUE;
    case VK_NEXT:
      ME_ArrowPageDown(editor, p);
      ME_ClearTempStyle(editor);
      ME_SendSelChange(editor);
      return TRUE;
  }
  
  editor->nUDArrowX = -1;
  switch(nVKey) {
    case VK_BACK: { /* FIXME backspace and delete aren't the same, they act different wrt paragraph style of the merged paragraph */
      if (GetWindowLongW(editor->hWnd, GWL_STYLE) & ES_READONLY)
        return FALSE;
      if (ME_IsSelection(editor))
      {
        editor->bCaretAtEnd = FALSE; /* FIXME or maybe not */
        ME_DeleteSelection(editor);
        ME_UpdateRepaint(editor);
        ME_SendRequestResize(editor, FALSE);
        return TRUE;
      }
      if (ME_ArrowLeft(editor, p)) {
        editor->bCaretAtEnd = FALSE; /* FIXME or maybe not */
        ME_ClearTempStyle(editor);
        ME_MoveCaret(editor);
        ME_DeleteTextAtCursor(editor, nCursor, 1);
        ME_UpdateRepaint(editor);
        ME_SendRequestResize(editor, FALSE);
      }
      return TRUE;
    }
    case VK_DELETE: {
      if (GetWindowLongW(editor->hWnd, GWL_STYLE) & ES_READONLY)
        return FALSE;
      /* editor->bCaretAtEnd = 0; FIXME or maybe not */
      if (ME_IsSelection(editor))
      {
        ME_DeleteSelection(editor);
        ME_ClearTempStyle(editor);
        ME_UpdateRepaint(editor);
        ME_SendRequestResize(editor, FALSE);
        return TRUE;
      }
      ME_DeleteTextAtCursor(editor, nCursor, 1);
      ME_ClearTempStyle(editor);
      ME_UpdateRepaint(editor);
      ME_SendRequestResize(editor, FALSE);
      return TRUE;
    }
    case VK_HOME: {
      if (GetKeyState(VK_CONTROL)<0)
        ME_ArrowCtrlHome(editor, p);
      else
        ME_ArrowHome(editor, p);
      editor->bCaretAtEnd = 0;
      ME_ClearTempStyle(editor);
      ME_RepaintSelection(editor, &tmp_curs);
      ME_SendSelChange(editor);
      return TRUE;
    }
    case VK_END: 
      if (GetKeyState(VK_CONTROL)<0)
        ME_ArrowCtrlEnd(editor, p);
      else
        ME_ArrowEnd(editor, p);
      ME_ClearTempStyle(editor);
      ME_RepaintSelection(editor, &tmp_curs);
      ME_SendSelChange(editor);
      return TRUE;
    case VK_LEFT:
      editor->bCaretAtEnd = 0;
      if (ME_CancelSelection(editor, -1))
        return TRUE;
      ME_ArrowLeft(editor, p);
      ME_RepaintSelection(editor, &tmp_curs);
      ME_ClearTempStyle(editor);
      ME_SendSelChange(editor);
      return TRUE;
    case VK_RIGHT:
      editor->bCaretAtEnd = 0;
      if (ME_CancelSelection(editor, +1))
        return TRUE;
      ME_ArrowRight(editor, p);
      ME_RepaintSelection(editor, &tmp_curs);
      ME_ClearTempStyle(editor);
      ME_SendSelChange(editor);
      return TRUE;
  }
  return FALSE;
}