// This file is part of RSS Guard.
//
// Copyright (C) 2011-2017 by Martin Rotter <rotter.martinos@gmail.com>
//
// RSS Guard 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.
//
// RSS Guard 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 RSS Guard. If not, see <http://www.gnu.org/licenses/>.

#include "gui/messagepreviewer.h"

#include "miscellaneous/application.h"
#include "network-web/webfactory.h"
#include "miscellaneous/databasequeries.h"
#include "gui/messagebox.h"
#include "gui/dialogs/formmain.h"
#include "services/abstract/serviceroot.h"

#include <QScrollBar>
#include <QToolBar>
#include <QToolTip>


void MessagePreviewer::createConnections() {
	connect(m_ui->m_txtMessage, &QTextBrowser::anchorClicked, [ = ](const QUrl & url) {
		if (!url.isEmpty()) {
			bool open_externally_now = qApp->settings()->value(GROUP(Browser),
			                                                   SETTING(Browser::OpenLinksInExternalBrowserRightAway)).toBool();

			if (open_externally_now) {
				qApp->web()->openUrlInExternalBrowser(url.toString());
			}
			else {
				// User clicked some URL. Open it in external browser or download?
				MessageBox box(qApp->mainForm());
				box.setText(tr("You clicked some link. You can download the link contents or open it in external web browser."));
				box.setInformativeText(tr("What action do you want to take?"));
				box.setDetailedText(url.toString());
				QAbstractButton* btn_open = box.addButton(tr("Open in external browser"), QMessageBox::ActionRole);
				QAbstractButton* btn_download = box.addButton(tr("Download"), QMessageBox::ActionRole);
				QAbstractButton* btn_cancel = box.addButton(QMessageBox::Cancel);
				bool always;
				MessageBox::setCheckBox(&box, tr("Always open links in external browser."), &always);
				box.setDefaultButton(QMessageBox::Cancel);
				box.exec();

				if (box.clickedButton() != box.button(QMessageBox::Cancel)) {
					// Store selected checkbox value.
					qApp->settings()->setValue(GROUP(Browser), Browser::OpenLinksInExternalBrowserRightAway, always);
				}

				if (box.clickedButton() == btn_open) {
					qApp->web()->openUrlInExternalBrowser(url.toString());
				}
				else if (box.clickedButton() == btn_download) {
					qApp->downloadManager()->download(url);
				}

				btn_download->deleteLater();
				btn_open->deleteLater();
				btn_cancel->deleteLater();
			}
		}
		else {
			MessageBox::show(qApp->mainForm(), QMessageBox::Warning, tr("Incorrect link"),
			                 tr("Selected hyperlink is invalid."));
		}
	});
	connect(m_actionMarkRead = m_toolBar->addAction(qApp->icons()->fromTheme("mail-mark-read"), tr("Mark message as read")),
	        &QAction::triggered,
	        this,
	        &MessagePreviewer::markMessageAsRead);
	connect(m_actionMarkUnread = m_toolBar->addAction(qApp->icons()->fromTheme("mail-mark-unread"), tr("Mark message as unread")),
	        &QAction::triggered,
	        this,
	        &MessagePreviewer::markMessageAsUnread);
	connect(m_actionSwitchImportance = m_toolBar->addAction(qApp->icons()->fromTheme("mail-mark-important"), tr("Switch message importance")),
	        &QAction::triggered,
	        this,
	        &MessagePreviewer::switchMessageImportance);
	connect(m_ui->m_txtMessage,
	        static_cast<void (QTextBrowser::*)(const QString&)>(&QTextBrowser::highlighted),
	[ = ](const QString & text) {
		Q_UNUSED(text)
		QToolTip::showText(QCursor::pos(), tr("Click this link to download it or open it with external browser."), this);
	});
}

MessagePreviewer::MessagePreviewer(QWidget* parent) : QWidget(parent),
	m_ui(new Ui::MessagePreviewer), m_pictures(QStringList()) {
	m_ui->setupUi(this);
	m_ui->m_txtMessage->viewport()->setAutoFillBackground(true);
	m_toolBar = new QToolBar(this);
	m_toolBar->setOrientation(Qt::Vertical);
	m_ui->m_layout->addWidget(m_toolBar, 0, 0, -1, 1);
	createConnections();
	m_actionSwitchImportance->setCheckable(true);
	reloadFontSettings();
	clear();
}

MessagePreviewer::~MessagePreviewer() {
}

void MessagePreviewer::reloadFontSettings() {
	const Settings* settings = qApp->settings();
	QFont fon;
	fon.fromString(settings->value(GROUP(Messages),
	                               SETTING(Messages::PreviewerFontStandard)).toString());
	m_ui->m_txtMessage->setFont(fon);
}

void MessagePreviewer::clear() {
	m_ui->m_txtMessage->clear();
	m_pictures.clear();
	hide();
}

void MessagePreviewer::hideToolbar() {
	m_toolBar->setVisible(false);
}

void MessagePreviewer::loadMessage(const Message& message, RootItem* root) {
	m_message = message;
	m_root = root;

	if (!m_root.isNull()) {
		m_actionSwitchImportance->setChecked(m_message.m_isImportant);
		m_ui->m_txtMessage->setHtml(prepareHtmlForMessage(m_message));
		updateButtons();
		show();
		m_ui->m_txtMessage->verticalScrollBar()->triggerAction(QScrollBar::SliderToMinimum);
	}
}

void MessagePreviewer::markMessageAsRead() {
	markMessageAsReadUnread(RootItem::Read);
}

void MessagePreviewer::markMessageAsUnread() {
	markMessageAsReadUnread(RootItem::Unread);
}

void MessagePreviewer::markMessageAsReadUnread(RootItem::ReadStatus read) {
	if (!m_root.isNull()) {
		if (m_root->getParentServiceRoot()->onBeforeSetMessagesRead(m_root.data(),
		                                                            QList<Message>() << m_message,
		                                                            read)) {
			DatabaseQueries::markMessagesReadUnread(qApp->database()->connection(objectName(), DatabaseFactory::FromSettings),
			                                        QStringList() << QString::number(m_message.m_id),
			                                        read);
			m_root->getParentServiceRoot()->onAfterSetMessagesRead(m_root.data(),
			                                                       QList<Message>() << m_message,
			                                                       read);
			m_message.m_isRead = read == RootItem::Read;
			emit markMessageRead(m_message.m_id, read);
			updateButtons();
		}
	}
}

void MessagePreviewer::switchMessageImportance(bool checked) {
	if (!m_root.isNull()) {
		if (m_root->getParentServiceRoot()->onBeforeSwitchMessageImportance(m_root.data(),
		        QList<ImportanceChange>() << ImportanceChange(m_message,
		                                                      m_message.m_isImportant ?
		                                                      RootItem::NotImportant :
		                                                      RootItem::Important))) {
      DatabaseQueries::switchMessagesImportance(qApp->database()->connection(objectName(), DatabaseFactory::FromSettings),
			                                          QStringList() << QString::number(m_message.m_id));
			m_root->getParentServiceRoot()->onAfterSwitchMessageImportance(m_root.data(),
			        QList<ImportanceChange>() << ImportanceChange(m_message,
			                                                      m_message.m_isImportant ?
			                                                      RootItem::NotImportant :
			                                                      RootItem::Important));
			emit markMessageImportant(m_message.m_id, checked ? RootItem::Important : RootItem::NotImportant);
			m_message.m_isImportant = checked;
		}
	}
}

void MessagePreviewer::updateButtons() {
	m_actionMarkRead->setEnabled(!m_message.m_isRead);
	m_actionMarkUnread->setEnabled(m_message.m_isRead);
}

QString MessagePreviewer::prepareHtmlForMessage(const Message& message) {
	QString html = QString("<h2 align=\"center\">%1</h2>").arg(message.m_title);
	html += QString("[url] <a href=\"%1\">%1</a><br/>").arg(message.m_url);

	foreach (const Enclosure& enc, message.m_enclosures) {
		html += QString("[%2] <a href=\"%1\">%1</a><br/>").arg(enc.m_url, enc.m_mimeType);
	}

	int offset = 0;
	QRegExp imgTagRegex("\\<img[^\\>]*src\\s*=\\s*\"([^\"]*)\"[^\\>]*\\>", Qt::CaseInsensitive);
	imgTagRegex.setMinimal(true);

	while ((offset = imgTagRegex.indexIn(message.m_contents, offset)) != -1) {
		m_pictures.append(imgTagRegex.cap(1));
		offset += imgTagRegex.matchedLength();
		html += QString("[%2] <a href=\"%1\">%1</a><br/>").arg(imgTagRegex.cap(1), tr("image"));
	}

	html += "<br/>";
	html += message.m_contents;
	return html;
}