/*
 * Copyright (c) 2013 Maximilian Güntner <maximilian.guentner@gmail.com>
 *
 * This file is subject to the terms and conditions of version 2 of
 * the GNU General Public License.  See the file gpl-2.0.txt in the main
 * directory of this archive for more details.
 *
 * Original License:
 *
 * This file is part of the Nepomuk widgets collection
 * Copyright (c) 2013 Denis Steckelmacher <steckdenis@yahoo.fr>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License version 2.1 as published by the Free Software Foundation,
 * or 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
*/

#include "groupedlineedit.h"

#include <QFontMetrics>
#include <QStyleOptionFrameV3>
#include <QFontMetrics>
#include <QApplication>
#include <QScrollBar>
#include <QTextDocument>
#include <QTextBlock>
#include <QTextLayout>
#include <QTextLine>
#include <QPainter>
#include <QPainterPath>
#include <QBrush>
#include <QColor>
#include <QPalette>
#include <QDebug>

struct GroupedLineEdit::Private {
	struct Block {
		int start;
		int end;
		QString text;
	};
	QVector<Block> blocks;
	QVector<QColor> colors;
};

GroupedLineEdit::GroupedLineEdit(QWidget* parent)
	: QPlainTextEdit(parent),
	  d(new Private)
{
	setWordWrapMode(QTextOption::NoWrap);
	setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);

	setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
	setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);

	document()->setMaximumBlockCount(1);
}


GroupedLineEdit::~GroupedLineEdit()
{
	delete d;
}

QString GroupedLineEdit::text() const
{
	// Remove the block crosses from the text
	return toPlainText();
}

int GroupedLineEdit::cursorPosition() const
{
	return textCursor().positionInBlock();
}

void GroupedLineEdit::addBlock(int start, int end)
{
	Private::Block block;

	block.start = start;
	block.end = end;
	block.text = text().mid(start, end-start+1).trimmed();
	d->blocks.append(block);
	viewport()->update();
}

void GroupedLineEdit::addColor(QColor color)
{
	d->colors.append(color);
}

void GroupedLineEdit::removeAllColors()
{
	d->colors.clear();
}

QStringList GroupedLineEdit::getBlockStringList()
{
	QStringList retList;
	Private::Block block;
	foreach(block, d->blocks)
		retList.append(block.text);
	return retList;
}

void GroupedLineEdit::setCursorPosition(int position)
{
	QTextCursor c = textCursor();
	c.setPosition(position, QTextCursor::MoveAnchor);
	setTextCursor(c);
}

void GroupedLineEdit::setText(const QString &text)
{
	setPlainText(text);
}

void GroupedLineEdit::clear()
{
	QPlainTextEdit::clear();
	removeAllBlocks();
}

void GroupedLineEdit::selectAll()
{
	QTextCursor c = textCursor();

	c.select(QTextCursor::LineUnderCursor);

	setTextCursor(c);
}

void GroupedLineEdit::removeAllBlocks()
{
	d->blocks.clear();
	viewport()->update();
}

QSize GroupedLineEdit::sizeHint() const
{
	QSize rs(
				40,
				document()->findBlock(0).layout()->lineAt(0).height() +
				document()->documentMargin() * 2 +
				frameWidth() * 2
				);

	return rs;
}

QSize GroupedLineEdit::minimumSizeHint() const
{
	return sizeHint();
}

void GroupedLineEdit::keyPressEvent(QKeyEvent *e)
{
	switch (e->key()) {
	case Qt::Key_Return:
	case Qt::Key_Enter:
		emit editingFinished();
		return;
	}
	QPlainTextEdit::keyPressEvent(e);
}

void GroupedLineEdit::paintEvent(QPaintEvent *e)
{
#if !defined __APPLE__
	// for reasons we don't understand, yet, touching the painter
	// here (even drawing the fill rect) causes the QPlainTextEdit
	// paintEvent to not draw the text on MacOS.
	// So as a workaround until this is better understood we need
	// to disable the eye candy
	QTextLine line = document()->findBlock(0).layout()->lineAt(0);
	QPainter painter(viewport());

	painter.setRenderHint(QPainter::Antialiasing, true);
	painter.fillRect(0, 0, viewport()->width(), viewport()->height(), palette().base());

	QVectorIterator<QColor> i(d->colors);
	i.toFront();
	foreach (const Private::Block &block, d->blocks) {
		qreal start_x = line.cursorToX(block.start, QTextLine::Trailing);
		qreal end_x = line.cursorToX(block.end + 1, QTextLine::Leading);
		QPainterPath path;
		QRectF rectangle(
					start_x - 1.0 - double(horizontalScrollBar()->value()),
					1.0,
					end_x - start_x + 2.0,
					double(viewport()->height() - 2)
					);
		if (! i.hasNext())
			i.toFront();
		path.addRoundedRect(rectangle, 5.0, 5.0);
		painter.setPen(i.peekNext());
		if (palette().color(QPalette::Text).lightnessF() <= 0.3 )
			painter.setBrush(i.next().lighter());
		else if (palette().color(QPalette::Text).lightnessF() <= 0.6 )
			painter.setBrush(i.next());
		else
			painter.setBrush(i.next().darker());
		painter.drawPath(path);
	}
#endif
	QPlainTextEdit::paintEvent(e);
}
