/*
** Buffer replacement wrapper routine to be used for inserting output from
** a command into the buffer, which takes into account that the buffer may
** have been shrunken by the user (eg, by Undo). If necessary, the starting
** and ending positions (part of the state of the command) are corrected.
*/
static void safeBufReplace(textBuffer *buf, int *start, int *end,
const char *text)
{
if (*start > buf->length)
*start = buf->length;
if (*end > buf->length)
*end = buf->length;
BufReplace(buf, *start, *end, text);
}
/*
** Cancel a block drag operation
*/
void CancelBlockDrag(TextWidget tw)
{
textBuffer *buf = tw->text.textD->buffer;
textBuffer *origBuf = tw->text.dragOrigBuf;
selection *origSel = &origBuf->primary;
int modRangeStart = -1, origModRangeEnd, bufModRangeEnd;
char *repText;
dragEndCBStruct endStruct;
/* If the operation was a move, make the modify range reflect the
removal of the text from the starting position */
if (tw->text.dragSourceDeleted != 0)
trackModifyRange(&modRangeStart, &bufModRangeEnd, &origModRangeEnd,
tw->text.dragSourceDeletePos, tw->text.dragSourceInserted,
tw->text.dragSourceDeleted);
/* Include the insert being undone from the last step in the modified
range. */
trackModifyRange(&modRangeStart, &bufModRangeEnd, &origModRangeEnd,
tw->text.dragInsertPos, tw->text.dragInserted, tw->text.dragDeleted);
/* Make the changes in the buffer */
repText = BufGetRange(origBuf, modRangeStart, origModRangeEnd);
BufReplace(buf, modRangeStart, bufModRangeEnd, repText);
XtFree(repText);
/* Reset the selection and cursor position */
if (origSel->rectangular)
BufRectSelect(buf, origSel->start, origSel->end, origSel->rectStart,
origSel->rectEnd);
else
BufSelect(buf, origSel->start, origSel->end);
TextDSetInsertPosition(tw->text.textD, buf->cursorPosHint);
XtCallCallbacks((Widget)tw, textNcursorMovementCallback, NULL);
tw->text.emTabsBeforeCursor = 0;
/* Free the backup buffer */
BufFree(origBuf);
/* Indicate end of drag */
tw->text.dragState = DRAG_CANCELED;
/* Call finish-drag calback */
endStruct.startPos = 0;
endStruct.nCharsDeleted = 0;
endStruct.nCharsInserted = 0;
endStruct.deletedText = NULL;
XtCallCallbacks((Widget)tw, textNdragEndCallback, (XtPointer)&endStruct);
}
/*
** Reposition the primary-selected text that is being dragged as a block
** for a new mouse position of (x, y)
*/
void BlockDragSelection(TextWidget tw, int x, int y, int dragType)
{
textDisp *textD = tw->text.textD;
textBuffer *buf = textD->buffer;
int fontHeight = textD->fontStruct->ascent + textD->fontStruct->descent;
int fontWidth = textD->fontStruct->max_bounds.width;
textBuffer *origBuf = tw->text.dragOrigBuf;
int dragXOffset = tw->text.dragXOffset;
textBuffer *tempBuf;
selection *origSel = &origBuf->primary;
int rectangular = origSel->rectangular;
int overlay, oldDragType = tw->text.dragType;
int nLines = tw->text.dragNLines;
int insLineNum, insLineStart, insRectStart, insRectEnd, insStart;
char *repText, *text, *insText;
int modRangeStart = -1, tempModRangeEnd = -1, bufModRangeEnd = -1;
int referenceLine, referencePos, tempStart, tempEnd, origSelLen;
int insertInserted, insertDeleted, row, column;
int origSelLineStart, origSelLineEnd;
int sourceInserted, sourceDeleted, sourceDeletePos;
if (tw->text.dragState != PRIMARY_BLOCK_DRAG)
return;
/* The operation of block dragging is simple in theory, but not so simple
in practice. There is a backup buffer (tw->text.dragOrigBuf) which
holds a copy of the buffer as it existed before the drag. When the
user drags the mouse to a new location, this routine is called, and
a temporary buffer is created and loaded with the local part of the
buffer (from the backup) which might be changed by the drag. The
changes are all made to this temporary buffer, and the parts of this
buffer which then differ from the real (displayed) buffer are used to
replace those parts, thus one replace operation serves as both undo
and modify. This double-buffering of the operation prevents excessive
redrawing (though there is still plenty of needless redrawing due to
re-selection and rectangular operations).
The hard part is keeping track of the changes such that a single replace
operation will do everyting. This is done using a routine called
trackModifyRange which tracks expanding ranges of changes in the two
buffers in modRangeStart, tempModRangeEnd, and bufModRangeEnd. */
/* Create a temporary buffer for accumulating changes which will
eventually be replaced in the real buffer. Load the buffer with the
range of characters which might be modified in this drag step
(this could be tighter, but hopefully it's not too slow) */
tempBuf = BufCreate();
tempBuf->tabDist = buf->tabDist;
tempBuf->useTabs = buf->useTabs;
tempStart = min3(tw->text.dragInsertPos, origSel->start,
BufCountBackwardNLines(buf, textD->firstChar, nLines+2));
tempEnd = BufCountForwardNLines(buf, max3(tw->text.dragInsertPos,
origSel->start, textD->lastChar), nLines+2) +
origSel->end - origSel->start;
text = BufGetRange(origBuf, tempStart, tempEnd);
BufSetAll(tempBuf, text);
XtFree(text);
/* If the drag type is USE_LAST, use the last dragType applied */
if (dragType == USE_LAST)
dragType = tw->text.dragType;
overlay = dragType == DRAG_OVERLAY_MOVE || dragType == DRAG_OVERLAY_COPY;
/* Overlay mode uses rectangular selections whether or not the original
was rectangular. To use a plain selection as if it were rectangular,
the start and end positions need to be moved to the line boundaries
and trailing newlines must be excluded */
origSelLineStart = BufStartOfLine(origBuf, origSel->start);
if (!rectangular && BufGetCharacter(origBuf, origSel->end - 1) == '\n')
origSelLineEnd = origSel->end - 1;
else
origSelLineEnd = BufEndOfLine(origBuf, origSel->end);
if (!rectangular && overlay && nLines != 0)
dragXOffset -= fontWidth * (origSel->rectStart -
(origSel->start - origSelLineStart));
/* If the drag operation is of a different type than the last one, and the
operation is a move, expand the modified-range to include undoing the
text-removal at the site from which the text was dragged. */
if (dragType != oldDragType && tw->text.dragSourceDeleted != 0)
trackModifyRange(&modRangeStart, &bufModRangeEnd, &tempModRangeEnd,
tw->text.dragSourceDeletePos, tw->text.dragSourceInserted,
tw->text.dragSourceDeleted);
/* Do, or re-do the original text removal at the site where a move began.
If this part has not changed from the last call, do it silently to
bring the temporary buffer in sync with the real (displayed)
buffer. If it's being re-done, track the changes to complete the
redo operation begun above */
if (dragType == DRAG_MOVE || dragType == DRAG_OVERLAY_MOVE) {
if (rectangular || overlay) {
int prevLen = tempBuf->length;
origSelLen = origSelLineEnd - origSelLineStart;
if (overlay)
BufClearRect(tempBuf, origSelLineStart-tempStart,
origSelLineEnd-tempStart, origSel->rectStart,
origSel->rectEnd);
else
BufRemoveRect(tempBuf, origSelLineStart-tempStart,
origSelLineEnd-tempStart, origSel->rectStart,
origSel->rectEnd);
sourceDeletePos = origSelLineStart;
sourceInserted = origSelLen - prevLen + tempBuf->length;
sourceDeleted = origSelLen;
} else {
BufRemove(tempBuf, origSel->start - tempStart,
origSel->end - tempStart);
sourceDeletePos = origSel->start;
sourceInserted = 0;
sourceDeleted = origSel->end - origSel->start;
}
if (dragType != oldDragType)
trackModifyRange(&modRangeStart, &tempModRangeEnd, &bufModRangeEnd,
sourceDeletePos, sourceInserted, sourceDeleted);
} else {
sourceDeletePos = 0;
sourceInserted = 0;
sourceDeleted = 0;
}
/* Expand the modified-range to include undoing the insert from the last
call. */
trackModifyRange(&modRangeStart, &bufModRangeEnd, &tempModRangeEnd,
tw->text.dragInsertPos, tw->text.dragInserted, tw->text.dragDeleted);
/* Find the line number and column of the insert position. Note that in
continuous wrap mode, these must be calculated as if the text were
not wrapped */
TextDXYToUnconstrainedPosition(textD, max(0, x - dragXOffset),
max(0, y - (tw->text.dragYOffset % fontHeight)), &row, &column);
column = TextDOffsetWrappedColumn(textD, row, column);
row = TextDOffsetWrappedRow(textD, row);
insLineNum = row + textD->topLineNum - tw->text.dragYOffset / fontHeight;
/* find a common point of reference between the two buffers, from which
the insert position line number can be translated to a position */
if (textD->firstChar > modRangeStart) {
referenceLine = textD->topLineNum -
BufCountLines(buf, modRangeStart, textD->firstChar);
referencePos = modRangeStart;
} else {
referencePos = textD->firstChar;
referenceLine = textD->topLineNum;
}
/* find the position associated with the start of the new line in the
temporary buffer */
insLineStart = findRelativeLineStart(tempBuf, referencePos - tempStart,
referenceLine, insLineNum) + tempStart;
if (insLineStart - tempStart == tempBuf->length)
insLineStart = BufStartOfLine(tempBuf, insLineStart - tempStart) +
tempStart;
/* Find the actual insert position */
if (rectangular || overlay) {
insStart = insLineStart;
insRectStart = column;
} else { /* note, this will fail with proportional fonts */
insStart = BufCountForwardDispChars(tempBuf, insLineStart - tempStart,
column) + tempStart;
insRectStart = 0;
}
/* If the position is the same as last time, don't bother drawing (it
would be nice if this decision could be made earlier) */
if (insStart == tw->text.dragInsertPos &&
insRectStart == tw->text.dragRectStart && dragType == oldDragType) {
BufFree(tempBuf);
return;
}
/* Do the insert in the temporary buffer */
if (rectangular || overlay) {
insText = BufGetTextInRect(origBuf, origSelLineStart, origSelLineEnd,
origSel->rectStart, origSel->rectEnd);
if (overlay)
BufOverlayRect(tempBuf, insStart - tempStart, insRectStart,
insRectStart + origSel->rectEnd - origSel->rectStart,
insText, &insertInserted, &insertDeleted);
else
BufInsertCol(tempBuf, insRectStart, insStart - tempStart, insText,
&insertInserted, &insertDeleted);
trackModifyRange(&modRangeStart, &tempModRangeEnd, &bufModRangeEnd,
insStart, insertInserted, insertDeleted);
XtFree(insText);
} else {
insText = BufGetSelectionText(origBuf);
BufInsert(tempBuf, insStart - tempStart, insText);
trackModifyRange(&modRangeStart, &tempModRangeEnd, &bufModRangeEnd,
insStart, origSel->end - origSel->start, 0);
insertInserted = origSel->end - origSel->start;
insertDeleted = 0;
XtFree(insText);
}
/* Make the changes in the real buffer */
repText = BufGetRange(tempBuf, modRangeStart - tempStart,
tempModRangeEnd - tempStart);
BufFree(tempBuf);
TextDBlankCursor(textD);
BufReplace(buf, modRangeStart, bufModRangeEnd, repText);
XtFree(repText);
/* Store the necessary information for undoing this step */
tw->text.dragInsertPos = insStart;
tw->text.dragRectStart = insRectStart;
tw->text.dragInserted = insertInserted;
tw->text.dragDeleted = insertDeleted;
tw->text.dragSourceDeletePos = sourceDeletePos;
tw->text.dragSourceInserted = sourceInserted;
tw->text.dragSourceDeleted = sourceDeleted;
tw->text.dragType = dragType;
/* Reset the selection and cursor position */
if (rectangular || overlay) {
insRectEnd = insRectStart + origSel->rectEnd - origSel->rectStart;
BufRectSelect(buf, insStart, insStart + insertInserted, insRectStart,
insRectEnd);
TextDSetInsertPosition(textD, BufCountForwardDispChars(buf,
BufCountForwardNLines(buf, insStart, tw->text.dragNLines),
insRectEnd));
} else {
BufSelect(buf, insStart, insStart + origSel->end - origSel->start);
TextDSetInsertPosition(textD, insStart + origSel->end - origSel->start);
}
TextDUnblankCursor(textD);
XtCallCallbacks((Widget)tw, textNcursorMovementCallback, (XtPointer)NULL);
tw->text.emTabsBeforeCursor = 0;
}
