/*
    Copyright 2006-2008 by Robert Knight <robertknight@gmail.com>

    This program 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 2 of the License, or
    (at your option) any later version.

    This program 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 this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301  USA.
*/

// Own
#include "IncrementalSearchBar.h"

// Qt
#include <QHBoxLayout>
#include <QKeyEvent>
#include <QTimer>
#include <QToolButton>
#include <QMenu>
#include <QApplication>

// KDE
#include <KColorScheme>
#include <QLineEdit>
#include <KLocalizedString>
#include "KonsoleSettings.h"

using namespace Konsole;

IncrementalSearchBar::IncrementalSearchBar(QWidget *parent) :
    QWidget(parent),
    _searchEdit(nullptr),
    _caseSensitive(nullptr),
    _regExpression(nullptr),
    _highlightMatches(nullptr),
    _reverseSearch(nullptr),
    _findNextButton(nullptr),
    _findPreviousButton(nullptr),
    _searchFromButton(nullptr),
    _searchTimer(nullptr)
{
    setPalette(qApp->palette());
    setAutoFillBackground(true);

    // SubWindow flag limits tab focus switching to this widget
    setWindowFlags(windowFlags() | Qt::SubWindow);

    _searchEdit = new QLineEdit(this);
    _searchEdit->setClearButtonEnabled(true);
    _searchEdit->installEventFilter(this);
    _searchEdit->setPlaceholderText(i18nc("@label:textbox", "Find..."));
    _searchEdit->setObjectName(QStringLiteral("search-edit"));
    _searchEdit->setToolTip(i18nc("@info:tooltip", "Enter the text to search for here"));
    _searchEdit->setCursor(Qt::IBeamCursor);
    _searchEdit->setStyleSheet(QString());
    _searchEdit->setFont(QApplication::font());
    // When the widget focus is set, focus input box instead
    setFocusProxy(_searchEdit);

    setCursor(Qt::ArrowCursor);
    // text box may be a minimum of 6 characters wide and a maximum of 10 characters wide
    // (since the maxWidth metric is used here, more characters probably will fit in than 6
    //  and 10)
    QFontMetrics metrics(_searchEdit->font());
    int maxWidth = metrics.maxWidth();
    _searchEdit->setMinimumWidth(maxWidth * 6);
    _searchEdit->setMaximumWidth(maxWidth * 10);

    _searchTimer = new QTimer(this);
    _searchTimer->setInterval(250);
    _searchTimer->setSingleShot(true);
    connect(_searchTimer, &QTimer::timeout, this,
            &Konsole::IncrementalSearchBar::notifySearchChanged);
    connect(_searchEdit, &QLineEdit::textChanged, _searchTimer,
            static_cast<void (QTimer::*)()>(&QTimer::start));

    _findNextButton = new QToolButton(this);
    _findNextButton->setObjectName(QStringLiteral("find-next-button"));
    _findNextButton->setText(i18nc("@action:button Go to the next phrase", "Next"));
    _findNextButton->setToolButtonStyle(Qt::ToolButtonIconOnly);
    _findNextButton->setAutoRaise(true);
    _findNextButton->setToolTip(i18nc("@info:tooltip",
                                      "Find the next match for the current search phrase"));
    _findNextButton->installEventFilter(this);
    connect(_findNextButton, &QToolButton::clicked, this,
            &Konsole::IncrementalSearchBar::findNextClicked);

    _findPreviousButton = new QToolButton(this);
    _findPreviousButton->setAutoRaise(true);
    _findPreviousButton->setObjectName(QStringLiteral("find-previous-button"));
    _findPreviousButton->setText(i18nc("@action:button Go to the previous phrase", "Previous"));
    _findPreviousButton->setToolButtonStyle(Qt::ToolButtonIconOnly);
    _findPreviousButton->setToolTip(i18nc("@info:tooltip",
                                          "Find the previous match for the current search phrase"));
    _findPreviousButton->installEventFilter(this);
    connect(_findPreviousButton, &QToolButton::clicked, this,
            &Konsole::IncrementalSearchBar::findPreviousClicked);

    _searchFromButton = new QToolButton(this);
    _searchFromButton->setAutoRaise(true);
    _searchFromButton->setObjectName(QStringLiteral("search-from-button"));
    _searchFromButton->installEventFilter(this);
    connect(_searchFromButton, &QToolButton::clicked, this,
            &Konsole::IncrementalSearchBar::searchFromClicked);

    auto optionsButton = new QToolButton(this);
    optionsButton->setObjectName(QStringLiteral("find-options-button"));
    optionsButton->setCheckable(false);
    optionsButton->setPopupMode(QToolButton::InstantPopup);
    optionsButton->setToolButtonStyle(Qt::ToolButtonIconOnly);
    optionsButton->setToolTip(i18nc("@info:tooltip", "Display the options menu"));
    optionsButton->setIcon(QIcon::fromTheme(QStringLiteral("configure")));
    optionsButton->setAutoRaise(true);
    optionsButton->installEventFilter(this);

    auto closeButton = new QToolButton(this);
    closeButton->setObjectName(QStringLiteral("close-button"));
    closeButton->setToolTip(i18nc("@info:tooltip", "Close the search bar"));
    closeButton->setAutoRaise(true);
    closeButton->setIcon(QIcon::fromTheme(QStringLiteral("dialog-close")));
    closeButton->installEventFilter(this);
    connect(closeButton, &QToolButton::clicked, this, &Konsole::IncrementalSearchBar::closeClicked);

    // Fill the options menu
    auto optionsMenu = new QMenu(this);
    optionsButton->setMenu(optionsMenu);

    _caseSensitive = optionsMenu->addAction(i18nc("@item:inmenu", "Case sensitive"));
    _caseSensitive->setCheckable(true);
    _caseSensitive->setToolTip(i18nc("@info:tooltip", "Sets whether the search is case sensitive"));
    connect(_caseSensitive, &QAction::toggled, this,
            &Konsole::IncrementalSearchBar::matchCaseToggled);

    _regExpression = optionsMenu->addAction(i18nc("@item:inmenu", "Match regular expression"));
    _regExpression->setCheckable(true);
    connect(_regExpression, &QAction::toggled, this,
            &Konsole::IncrementalSearchBar::matchRegExpToggled);

    _highlightMatches = optionsMenu->addAction(i18nc("@item:inmenu", "Highlight all matches"));
    _highlightMatches->setCheckable(true);
    _highlightMatches->setToolTip(i18nc("@info:tooltip",
                                        "Sets whether matching text should be highlighted"));
    connect(_highlightMatches, &QAction::toggled, this,
            &Konsole::IncrementalSearchBar::highlightMatchesToggled);

    _reverseSearch = optionsMenu->addAction(i18nc("@item:inmenu", "Search backwards"));
    _reverseSearch->setCheckable(true);
    _reverseSearch->setToolTip(i18nc("@info:tooltip",
                                     "Sets whether search should start from the bottom"));
    connect(_reverseSearch, &QAction::toggled, this,
            &Konsole::IncrementalSearchBar::updateButtonsAccordingToReverseSearchSetting);
    updateButtonsAccordingToReverseSearchSetting();
    setOptions();

    auto barLayout = new QHBoxLayout(this);
    barLayout->addWidget(_searchEdit);
    barLayout->addWidget(_findNextButton);
    barLayout->addWidget(_findPreviousButton);
    barLayout->addWidget(_searchFromButton);
    barLayout->addWidget(optionsButton);
    barLayout->addWidget(closeButton);
    barLayout->setContentsMargins(4, 4, 4, 4);
    barLayout->setSpacing(0);

    setLayout(barLayout);
    adjustSize();
    clearLineEdit();
}

void IncrementalSearchBar::notifySearchChanged()
{
    emit searchChanged(searchText());
}

void IncrementalSearchBar::updateButtonsAccordingToReverseSearchSetting()
{
    Q_ASSERT(_reverseSearch);
    if (_reverseSearch->isChecked()) {
        _searchFromButton->setToolTip(i18nc("@info:tooltip",
                                            "Search for the current search phrase from the bottom"));
        _searchFromButton->setIcon(QIcon::fromTheme(QStringLiteral("go-bottom")));
        _findNextButton->setIcon(QIcon::fromTheme(QStringLiteral("go-up")));
        _findPreviousButton->setIcon(QIcon::fromTheme(QStringLiteral("go-down")));
    } else {
        _searchFromButton->setToolTip(i18nc("@info:tooltip",
                                            "Search for the current search phrase from the top"));
        _searchFromButton->setIcon(QIcon::fromTheme(QStringLiteral("go-top")));
        _findNextButton->setIcon(QIcon::fromTheme(QStringLiteral("go-down")));
        _findPreviousButton->setIcon(QIcon::fromTheme(QStringLiteral("go-up")));
    }
}

QString IncrementalSearchBar::searchText()
{
    return _searchEdit->text();
}

void IncrementalSearchBar::setSearchText(const QString &text)
{
    if (text != searchText()) {
        _searchEdit->setText(text);
    }
}

bool IncrementalSearchBar::eventFilter(QObject *watched, QEvent *event)
{
    if (event->type() == QEvent::KeyPress || event->type() == QEvent::KeyRelease) {
        auto *keyEvent = static_cast<QKeyEvent *>(event);
        QToolButton *toolButton = nullptr;

        if (keyEvent->key() == Qt::Key_Return) {
            if (watched == _searchEdit && event->type() == QEvent::KeyPress) {
                if (keyEvent->modifiers() == Qt::NoModifier) {
                    _findNextButton->click();
                    return true;
                }
                if (keyEvent->modifiers() == Qt::ShiftModifier) {
                    _findPreviousButton->click();
                    return true;
                }
                if (keyEvent->modifiers() == Qt::ControlModifier) {
                    _searchFromButton->click();
                    return true;
                }
            } else if ((toolButton = qobject_cast<QToolButton *>(watched)) != nullptr) {
                if(event->type() == QEvent::KeyPress && !toolButton->isDown()) {
                    toolButton->setDown(true);
                    toolButton->pressed();
                } else if (toolButton->isDown()) {
                    toolButton->setDown(keyEvent->isAutoRepeat());
                    toolButton->released();
                    toolButton->click();
                }
                return true;
            }
        }
    }
    return QWidget::eventFilter(watched, event);
}

void IncrementalSearchBar::keyPressEvent(QKeyEvent *event)
{
    static auto movementKeysToPassAlong = QSet<int>{
        Qt::Key_PageUp, Qt::Key_PageDown, Qt::Key_Up, Qt::Key_Down
    };

    if (movementKeysToPassAlong.contains(event->key())
        && (event->modifiers() == Qt::ShiftModifier)) {
        emit unhandledMovementKeyPressed(event);
    }

    if (event->key() == Qt::Key_Escape) {
        emit closeClicked();
    }
}

void IncrementalSearchBar::setVisible(bool visible)
{
    QWidget::setVisible(visible);

    if (visible) {
        focusLineEdit();
    }
}

void IncrementalSearchBar::setFoundMatch(bool match)
{
    if (_searchEdit->text().isEmpty()) {
         clearLineEdit();
         return;
    }

    const auto backgroundBrush = KStatefulBrush(KColorScheme::View,
        match ? KColorScheme::PositiveBackground : KColorScheme::NegativeBackground);

    const auto matchStyleSheet = QStringLiteral("QLineEdit{ background-color:%1 }")
                              .arg(backgroundBrush.brush(_searchEdit).color().name());

    _searchEdit->setStyleSheet(matchStyleSheet);
}

void IncrementalSearchBar::clearLineEdit()
{
    _searchEdit->setStyleSheet(QString());
}

void IncrementalSearchBar::focusLineEdit()
{
    _searchEdit->setFocus(Qt::ActiveWindowFocusReason);
    _searchEdit->selectAll();
}

const QBitArray IncrementalSearchBar::optionsChecked()
{
    QBitArray options(4, false);
    options.setBit(MatchCase, _caseSensitive->isChecked());
    options.setBit(RegExp, _regExpression->isChecked());
    options.setBit(HighlightMatches, _highlightMatches->isChecked());
    options.setBit(ReverseSearch, _reverseSearch->isChecked());
    return options;
}

void IncrementalSearchBar::setOptions()
{
    _caseSensitive->setChecked(KonsoleSettings::searchCaseSensitive());
    _regExpression->setChecked(KonsoleSettings::searchRegExpression());
    _highlightMatches->setChecked(KonsoleSettings::searchHighlightMatches());
    _reverseSearch->setChecked(KonsoleSettings::searchReverseSearch());
}
