Method HistoryStep

GUI/RichTextarea.cpp:428–494

	}

	void	HistoryStep(bool redo)
	{
		Snapshot *&firstShot = redo ? firstShotR : firstShotU;
		Snapshot *&lastShot = redo ? lastShotR : lastShotU;
		// If there are no snapshots, exit
		if(!lastShot)
			return;

		// Set currLine to the old one
		data->currLine = data->firstLine;
		for(unsigned int i = 0; i < lastShot->startLine; i++)
			data->currLine = data->currLine->next;

		// Take a redo snapshot
		TakeSnapshot(data->currLine, lastShot->type == LINES_ADDED ? LINES_DELETED : (lastShot->type == LINES_DELETED ? LINES_ADDED : LINES_CHANGED), lastShot->type == LINES_ADDED ? lastShot->lines + 1 : (lastShot->type == LINES_DELETED ? lastShot->lines - 1 : lastShot->lines), !redo, false);

		// Disable selection
		data->selectionOn = false;

		// Restore cursor position
		data->cursorCharX = lastShot->cursorX;
		data->cursorCharY = lastShot->cursorY;
		// Restore selection state
		data->dragStartX = lastShot->selectStartX;
		data->dragStartY = lastShot->selectStartY;
		data->dragEndX = lastShot->selectEndX;
		data->dragEndY = lastShot->selectEndY;
		data->selectionOn = lastShot->selectionOn;

		// Copy previous contents of current line
		ExtendLine(data->currLine, lastShot->first->length);
		memcpy(data->currLine->data, lastShot->first->data, lastShot->first->length * sizeof(AreaChar));
		data->currLine->length = lastShot->first->length;
		// If lines were added by edit, remove them
		if(lastShot->type == LINES_ADDED)
		{
			data->lineCount -= lastShot->lines;
			for(unsigned int i = 0; i < lastShot->lines; i++)
				DeleteLine(data->currLine->next);
		}else if(lastShot->type == LINES_DELETED){	// If lines were deleted by edit, restore them
			AreaLine *curr = lastShot->first->next;
			data->lineCount += lastShot->lines - 1;
			for(unsigned int i = 0; i < lastShot->lines-1; i++)
			{
				data->currLine = InsertLineAfter(data->currLine);
				ExtendLine(data->currLine, curr->length);
				memcpy(data->currLine->data, curr->data, curr->length * sizeof(AreaChar));
				data->currLine->length = curr->length;
				data->currLine->lineStyle = curr->lineStyle;
				data->currLine->lineExtra = curr->lineExtra;
				curr = curr->next;
			}
		}

		// Remove snapshot
		if(lastShot->prevShot)
		{
			lastShot = lastShot->prevShot;