/*
 * Copyright (C) 2020 Gavin MacGregor
 *
 * This file is part of QTeletextMaker.
 *
 * QTeletextMaker is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * QTeletextMaker 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with QTeletextMaker.  If not, see <https://www.gnu.org/licenses/>.
 */

#include "levelonecommands.h"

#include "document.h"

OverwriteCharacterCommand::OverwriteCharacterCommand(TeletextDocument *teletextDocument, unsigned char newCharacter, QUndoCommand *parent) : QUndoCommand(parent)
{
	m_teletextDocument = teletextDocument;
	m_subPageIndex = teletextDocument->currentSubPageIndex();
	m_row = teletextDocument->cursorRow();
	m_column = teletextDocument->cursorColumn();
	m_oldCharacter = teletextDocument->currentSubPage()->character(m_row, m_column);
	m_newCharacter = newCharacter;
}

void OverwriteCharacterCommand::redo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->currentSubPage()->setCharacter(m_row, m_column, m_newCharacter);
	m_teletextDocument->moveCursor(m_row, m_column);
	m_teletextDocument->cursorRight();
	setText(QObject::tr("overwrite char"));
	emit m_teletextDocument->contentsChange(m_row);
}

void OverwriteCharacterCommand::undo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->currentSubPage()->setCharacter(m_row, m_column, m_oldCharacter);
	m_teletextDocument->moveCursor(m_row, m_column);
	setText(QObject::tr("overwrite char"));
	emit m_teletextDocument->contentsChange(m_row);
}


ToggleMosaicBitCommand::ToggleMosaicBitCommand(TeletextDocument *teletextDocument, unsigned char bitToToggle, QUndoCommand *parent) : QUndoCommand(parent)
{
	m_teletextDocument = teletextDocument;
	m_subPageIndex = teletextDocument->currentSubPageIndex();
	m_row = teletextDocument->cursorRow();
	m_column = teletextDocument->cursorColumn();
	m_oldCharacter = teletextDocument->currentSubPage()->character(m_row, m_column);
	if (bitToToggle == 0x20 || bitToToggle == 0x7f)
		m_newCharacter = bitToToggle;
	else
		m_newCharacter = m_oldCharacter ^ bitToToggle;
}

void ToggleMosaicBitCommand::redo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->currentSubPage()->setCharacter(m_row, m_column, m_newCharacter);
	m_teletextDocument->moveCursor(m_row, m_column);
	setText(QObject::tr("mosaic"));
	emit m_teletextDocument->contentsChange(m_row);
}

void ToggleMosaicBitCommand::undo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->currentSubPage()->setCharacter(m_row, m_column, m_oldCharacter);
	m_teletextDocument->moveCursor(m_row, m_column);
	setText(QObject::tr("mosaic"));
	emit m_teletextDocument->contentsChange(m_row);
}

bool ToggleMosaicBitCommand::mergeWith(const QUndoCommand *command)
{
	const ToggleMosaicBitCommand *previousCommand = static_cast<const ToggleMosaicBitCommand *>(command);

	if (m_subPageIndex != previousCommand->m_subPageIndex || m_row != previousCommand->m_row || m_column != previousCommand->m_column)
		return false;
	m_newCharacter = previousCommand->m_newCharacter;
	return true;
}


BackspaceCommand::BackspaceCommand(TeletextDocument *teletextDocument, QUndoCommand *parent) : QUndoCommand(parent)
{
	m_teletextDocument = teletextDocument;
	m_subPageIndex = teletextDocument->currentSubPageIndex();
	m_row = teletextDocument->cursorRow();
	m_column = teletextDocument->cursorColumn()-1;
	if (m_column == -1) {
		m_column = 39;
		if (--m_row == 0)
			m_row = 24;
	}
	m_deletedCharacter = teletextDocument->currentSubPage()->character(m_row, m_column);
}

void BackspaceCommand::redo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->currentSubPage()->setCharacter(m_row, m_column, 0x20);
	m_teletextDocument->moveCursor(m_row, m_column);
	setText(QObject::tr("backspace"));
	emit m_teletextDocument->contentsChange(m_row);
}

void BackspaceCommand::undo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->currentSubPage()->setCharacter(m_row, m_column, m_deletedCharacter);
	m_teletextDocument->moveCursor(m_row, m_column);
	m_teletextDocument->cursorRight();
	setText(QObject::tr("backspace"));
	emit m_teletextDocument->contentsChange(m_row);
}


InsertRowCommand::InsertRowCommand(TeletextDocument *teletextDocument, bool copyRow, QUndoCommand *parent) : QUndoCommand(parent)
{
	m_teletextDocument = teletextDocument;
	m_subPageIndex = teletextDocument->currentSubPageIndex();
	m_row = teletextDocument->cursorRow();
	m_copyRow = copyRow;
}

void InsertRowCommand::redo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->moveCursor(m_row, -1);
	// Store copy of the bottom row we're about to push out, for undo
	for (int c=0; c<40; c++)
		m_deletedBottomRow[c] = m_teletextDocument->currentSubPage()->character(23, c);
	// Shuffle lines below the inserting row downwards without affecting the FastText row
	for (int r=22; r>=m_row; r--)
		for (int c=0; c<40; c++)
			m_teletextDocument->currentSubPage()->setCharacter(r+1, c, m_teletextDocument->currentSubPage()->character(r, c));
	if (m_copyRow)
		setText(QObject::tr("insert copy row"));
	else {
		// The above shuffle leaves a duplicate of the current row, so blank it if requested
		for (int c=0; c<40; c++)
			m_teletextDocument->currentSubPage()->setCharacter(m_row, c, ' ');
		setText(QObject::tr("insert blank row"));
	}
	emit m_teletextDocument->refreshNeeded();
}

void InsertRowCommand::undo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->moveCursor(m_row, -1);
	// Shuffle lines below the deleting row upwards without affecting the FastText row
	for (int r=m_row; r<23; r++)
		for (int c=0; c<40; c++)
			m_teletextDocument->currentSubPage()->setCharacter(r, c, m_teletextDocument->currentSubPage()->character(r+1, c));
	// Now repair the bottom row we pushed out
	for (int c=0; c<40; c++)
		m_teletextDocument->currentSubPage()->setCharacter(23, c, m_deletedBottomRow[c]);
	if (m_copyRow)
		setText(QObject::tr("insert copy row"));
	else
		setText(QObject::tr("insert blank row"));
	emit m_teletextDocument->refreshNeeded();
}


DeleteRowCommand::DeleteRowCommand(TeletextDocument *teletextDocument, QUndoCommand *parent) : QUndoCommand(parent)
{
	m_teletextDocument = teletextDocument;
	m_subPageIndex = teletextDocument->currentSubPageIndex();
	m_row = teletextDocument->cursorRow();
}

void DeleteRowCommand::redo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->moveCursor(m_row, -1);
	// Store copy of the row we're going to delete, for undo
	for (int c=0; c<40; c++)
		m_deletedRow[c] = m_teletextDocument->currentSubPage()->character(m_row, c);
	// Shuffle lines below the deleting row upwards without affecting the FastText row
	for (int r=m_row; r<23; r++)
		for (int c=0; c<40; c++)
			m_teletextDocument->currentSubPage()->setCharacter(r, c, m_teletextDocument->currentSubPage()->character(r+1, c));
	// If we deleted the FastText row blank that row, otherwise blank the last row
	int blankingRow = (m_row < 24) ? 23 : 24;
		for (int c=0; c<40; c++)
			m_teletextDocument->currentSubPage()->setCharacter(blankingRow, c, ' ');
	setText(QObject::tr("delete row"));
	emit m_teletextDocument->refreshNeeded();
}

void DeleteRowCommand::undo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->moveCursor(m_row, -1);
	// Shuffle lines below the inserting row downwards without affecting the FastText row
	for (int r=22; r>=m_row; r--)
		for (int c=0; c<40; c++)
			m_teletextDocument->currentSubPage()->setCharacter(r+1, c, m_teletextDocument->currentSubPage()->character(r, c));
	// Now repair the row we deleted
	for (int c=0; c<40; c++)
		m_teletextDocument->currentSubPage()->setCharacter(m_row, c, m_deletedRow[c]);
	setText(QObject::tr("delete row"));
	emit m_teletextDocument->refreshNeeded();
}


InsertSubPageCommand::InsertSubPageCommand(TeletextDocument *teletextDocument, bool afterCurrentSubPage, bool copySubPage, QUndoCommand *parent) : QUndoCommand(parent)
{
	m_teletextDocument = teletextDocument;
	m_newSubPageIndex = teletextDocument->currentSubPageIndex()+afterCurrentSubPage;
	m_copySubPage = copySubPage;
}

void InsertSubPageCommand::redo()
{
	m_teletextDocument->insertSubPage(m_newSubPageIndex, m_copySubPage);
	m_teletextDocument->selectSubPageIndex(m_newSubPageIndex, true);
	setText(QObject::tr("insert subpage"));
}

void InsertSubPageCommand::undo()
{
	m_teletextDocument->deleteSubPage(m_newSubPageIndex);
	//TODO should we always wrench to "subpage viewed when we inserted"? Or just if subpage viewed is being deleted?
	m_teletextDocument->selectSubPageIndex(m_newSubPageIndex, true);
	setText(QObject::tr("insert subpage"));
}


SetColourCommand::SetColourCommand(TeletextDocument *teletextDocument, int colourIndex, int newColour, QUndoCommand *parent) : QUndoCommand(parent)
{
	m_teletextDocument = teletextDocument;
	m_subPageIndex = teletextDocument->currentSubPageIndex();
	m_colourIndex = colourIndex;
	m_oldColour = teletextDocument->currentSubPage()->CLUT(colourIndex);
	m_newColour = newColour;
}

void SetColourCommand::redo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->currentSubPage()->setCLUT(m_colourIndex, m_newColour);
	emit m_teletextDocument->colourChanged(m_colourIndex);
	setText(QObject::tr("colour change"));
	emit m_teletextDocument->refreshNeeded();
}

void SetColourCommand::undo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	m_teletextDocument->currentSubPage()->setCLUT(m_colourIndex, m_oldColour);
	emit m_teletextDocument->colourChanged(m_colourIndex);
	setText(QObject::tr("colour change"));
	emit m_teletextDocument->refreshNeeded();
}


ResetCLUTCommand::ResetCLUTCommand(TeletextDocument *teletextDocument, int colourTable, QUndoCommand *parent) : QUndoCommand(parent)
{
	m_teletextDocument = teletextDocument;
	m_subPageIndex = teletextDocument->currentSubPageIndex();
	m_colourTable = colourTable;
	for (int i=m_colourTable*8; i<m_colourTable*8+8; i++)
		m_oldColourEntry[i&7] = teletextDocument->currentSubPage()->CLUT(i);
}

void ResetCLUTCommand::redo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	for (int i=m_colourTable*8; i<m_colourTable*8+8; i++) {
		m_teletextDocument->currentSubPage()->setCLUT(i, m_teletextDocument->currentSubPage()->CLUT(i, 0));
		emit m_teletextDocument->colourChanged(i);
	}
	setText(QObject::tr("CLUT %1 reset").arg(m_colourTable));
	emit m_teletextDocument->refreshNeeded();
}

void ResetCLUTCommand::undo()
{
	m_teletextDocument->selectSubPageIndex(m_subPageIndex);
	for (int i=m_colourTable*8; i<m_colourTable*8+8; i++) {
		m_teletextDocument->currentSubPage()->setCLUT(i, m_oldColourEntry[i&7]);
		emit m_teletextDocument->colourChanged(i);
	}
	setText(QObject::tr("CLUT %1 reset").arg(m_colourTable));
	emit m_teletextDocument->refreshNeeded();
}