/****************************************************************************

**

** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the examples of the Qt Toolkit.

**

**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#include <QtGui>

#include "mainwindow.h"

#include "previewform.h"

MainWindow::MainWindow()

{

    textEdit = new QTextEdit;

    textEdit->setLineWrapMode(QTextEdit::NoWrap);

    setCentralWidget(textEdit);

    findCodecs();

    previewForm = new PreviewForm(this);

    previewForm->setCodecList(codecs);

    createActions();

    createMenus();

    setWindowTitle(tr("Codecs"));

    resize(500, 400);

}

void MainWindow::open()

{

    QString fileName = QFileDialog::getOpenFileName(this);

    if (!fileName.isEmpty()) {

        QFile file(fileName);

        if (!file.open(QFile::ReadOnly)) {

            QMessageBox::warning(this, tr("Codecs"),

                                 tr("Cannot read file %1:\n%2")

                                 .arg(fileName)

                                 .arg(file.errorString()));

            return;

        }

        QByteArray data = file.readAll();

        previewForm->setEncodedData(data);

        if (previewForm->exec())

            textEdit->setPlainText(previewForm->decodedString());

    }

}

void MainWindow::save()

{

    QString fileName = QFileDialog::getSaveFileName(this);

    if (!fileName.isEmpty()) {

        QFile file(fileName);

        if (!file.open(QFile::WriteOnly | QFile::Text)) {

            QMessageBox::warning(this, tr("Codecs"),

                                 tr("Cannot write file %1:\n%2")

                                 .arg(fileName)

                                 .arg(file.errorString()));

            return;

        }

        QAction *action = qobject_cast<QAction *>(sender());

        QByteArray codecName = action->data().toByteArray();

        QTextStream out(&file);

        out.setCodec(codecName);

        out << textEdit->toPlainText();

    }

}

void MainWindow::about()

{

    QMessageBox::about(this, tr("About Codecs"),

            tr("The <b>Codecs</b> example demonstrates how to read and write "

               "files using various encodings."));

}

void MainWindow::aboutToShowSaveAsMenu()

{

    QString currentText = textEdit->toPlainText();

    foreach (QAction *action, saveAsActs) {

        QByteArray codecName = action->data().toByteArray();

        QTextCodec *codec = QTextCodec::codecForName(codecName);

        action->setVisible(codec && codec->canEncode(currentText));

    }

}

void MainWindow::findCodecs()

{

    QMap<QString, QTextCodec *> codecMap;

    QRegExp iso8859RegExp("ISO[- ]8859-([0-9]+).*");

    foreach (int mib, QTextCodec::availableMibs()) {

        QTextCodec *codec = QTextCodec::codecForMib(mib);

        QString sortKey = codec->name().toUpper();

        int rank;

        if (sortKey.startsWith("UTF-8")) {

            rank = 1;

        } else if (sortKey.startsWith("UTF-16")) {

            rank = 2;

        } else if (iso8859RegExp.exactMatch(sortKey)) {

            if (iso8859RegExp.cap(1).size() == 1)

                rank = 3;

            else

                rank = 4;

        } else {

            rank = 5;

        }

        sortKey.prepend(QChar('0' + rank));

        codecMap.insert(sortKey, codec);

    }

    codecs = codecMap.values();

}

void MainWindow::createActions()

{

    openAct = new QAction(tr("&Open..."), this);

    openAct->setShortcuts(QKeySequence::Open);

    connect(openAct, SIGNAL(triggered()), this, SLOT(open()));

    foreach (QTextCodec *codec, codecs) {

        QString text = tr("%1...").arg(QString(codec->name()));

        QAction *action = new QAction(text, this);

	action->setData(codec->name());

        connect(action, SIGNAL(triggered()), this, SLOT(save()));

        saveAsActs.append(action);

    }

    exitAct = new QAction(tr("E&xit"), this);

    exitAct->setShortcuts(QKeySequence::Quit);

    connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));

    aboutAct = new QAction(tr("&About"), this);

    connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));

    aboutQtAct = new QAction(tr("About &Qt"), this);

    connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));

}

void MainWindow::createMenus()

{

    saveAsMenu = new QMenu(tr("&Save As"), this);

    foreach (QAction *action, saveAsActs)

        saveAsMenu->addAction(action);

    connect(saveAsMenu, SIGNAL(aboutToShow()),

            this, SLOT(aboutToShowSaveAsMenu()));

    fileMenu = new QMenu(tr("&File"), this);

    fileMenu->addAction(openAct);

    fileMenu->addMenu(saveAsMenu);

    fileMenu->addSeparator();

    fileMenu->addAction(exitAct);

    helpMenu = new QMenu(tr("&Help"), this);

    helpMenu->addAction(aboutAct);

    helpMenu->addAction(aboutQtAct);

    menuBar()->addMenu(fileMenu);

    menuBar()->addSeparator();

    menuBar()->addMenu(helpMenu);

}