/*
MIT License

Copyright (c) 2026 Poul Sander

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

*/

#include "shortcutmanager.h"

#include <QKeyEvent>
#include <QSettings>
#include <QCoreApplication>

namespace {

struct ActionInfo {
    const char *name;        // settings key
    const char *description; // human-readable for help overlay / prefs table
    QKeySequence defaultKey;
    ShortcutManager::Category category;
};

// Order must match ShortcutManager::Action enum
static const ActionInfo kDefaults[ShortcutManager::ActionCount] = {
    {"ToggleHelp",      QT_TRANSLATE_NOOP("ShortcutManager", "Show/hide keyboard shortcuts"), QKeySequence(Qt::Key_F1),       ShortcutManager::CatNotConfigurable},
    {"CloseViewer",     QT_TRANSLATE_NOOP("ShortcutManager", "Close viewer"),                 QKeySequence(Qt::Key_Escape),   ShortcutManager::CatImageViewer},
    {"CloseViewerAlt",  QT_TRANSLATE_NOOP("ShortcutManager", "Close viewer (alt)"),           QKeySequence(Qt::Key_Return),   ShortcutManager::CatImageViewer},
    {"NextImage",       QT_TRANSLATE_NOOP("ShortcutManager", "Next image"),                   QKeySequence(Qt::Key_PageDown), ShortcutManager::CatImageViewer},
    {"PrevImage",       QT_TRANSLATE_NOOP("ShortcutManager", "Previous image"),               QKeySequence(Qt::Key_PageUp),   ShortcutManager::CatImageViewer},
    {"PanLeft",         QT_TRANSLATE_NOOP("ShortcutManager", "Pan left"),                     QKeySequence(Qt::Key_Left),     ShortcutManager::CatImageViewer},
    {"PanRight",        QT_TRANSLATE_NOOP("ShortcutManager", "Pan right"),                    QKeySequence(Qt::Key_Right),    ShortcutManager::CatImageViewer},
    {"PanUp",           QT_TRANSLATE_NOOP("ShortcutManager", "Pan up"),                       QKeySequence(Qt::Key_Up),       ShortcutManager::CatImageViewer},
    {"PanDown",         QT_TRANSLATE_NOOP("ShortcutManager", "Pan down"),                     QKeySequence(Qt::Key_Down),     ShortcutManager::CatImageViewer},
    {"ZoomOriginal",    QT_TRANSLATE_NOOP("ShortcutManager", "Zoom to original size"),        QKeySequence(Qt::Key_Slash),    ShortcutManager::CatImageViewer},
    {"ZoomFit",         QT_TRANSLATE_NOOP("ShortcutManager", "Zoom to fit screen"),           QKeySequence(Qt::Key_Asterisk), ShortcutManager::CatImageViewer},
    {"ZoomIn",          QT_TRANSLATE_NOOP("ShortcutManager", "Zoom in"),                      QKeySequence(Qt::Key_Plus),     ShortcutManager::CatImageViewer},
    {"ZoomOut",         QT_TRANSLATE_NOOP("ShortcutManager", "Zoom out"),                     QKeySequence(Qt::Key_Minus),    ShortcutManager::CatImageViewer},
    {"ToggleExif",      QT_TRANSLATE_NOOP("ShortcutManager", "Toggle EXIF info"),             QKeySequence(Qt::Key_I),        ShortcutManager::CatImageViewer},
    {"EditCaption",     QT_TRANSLATE_NOOP("ShortcutManager", "Edit caption"),                 QKeySequence(Qt::Key_E),        ShortcutManager::CatImageViewer},
    {"ToggleFullscreen",QT_TRANSLATE_NOOP("ShortcutManager", "Toggle fullscreen"),            QKeySequence(Qt::Key_F11),      ShortcutManager::CatImageViewer},
    {"ActivateEntry",   QT_TRANSLATE_NOOP("ShortcutManager", "Open folder / image"),          QKeySequence(Qt::Key_Return),   ShortcutManager::CatBrowser},
    {"PrevFolder",      QT_TRANSLATE_NOOP("ShortcutManager", "Previous folder"),              QKeySequence(Qt::ALT | Qt::Key_Left),  ShortcutManager::CatBrowser},
    {"NextFolder",      QT_TRANSLATE_NOOP("ShortcutManager", "Next folder"),                  QKeySequence(Qt::ALT | Qt::Key_Right), ShortcutManager::CatBrowser},
    {"MoveToTrash",     QT_TRANSLATE_NOOP("ShortcutManager", "Move image to trash"),          QKeySequence(Qt::Key_Delete),   ShortcutManager::CatBrowser},
};

} // namespace

ShortcutManager::ShortcutManager()
{
    resetToDefaults();
}

ShortcutManager &ShortcutManager::instance()
{
    static ShortcutManager mgr;
    return mgr;
}

QKeySequence ShortcutManager::shortcut(Action action) const
{
    if (action < 0 || action >= ActionCount)
        return {};
    return m_bindings[action].key;
}

QString ShortcutManager::displayKey(Action action) const
{
    if (action < 0 || action >= ActionCount)
        return {};
    return m_bindings[action].key.toString(QKeySequence::NativeText);
}

QString ShortcutManager::description(Action action) const
{
    return actionDescription(action);
}

void ShortcutManager::setShortcut(Action action, const QKeySequence &seq)
{
    if (action >= 0 && action < ActionCount)
        m_bindings[action].key = seq;
}

void ShortcutManager::resetToDefaults()
{
    for (int i = 0; i < ActionCount; ++i)
        m_bindings[i].key = kDefaults[i].defaultKey;
}

void ShortcutManager::load(QSettings &settings)
{
    settings.beginGroup("shortcuts");
    for (int i = 0; i < ActionCount; ++i) {
        if (kDefaults[i].category == CatNotConfigurable) {
            m_bindings[i].key = kDefaults[i].defaultKey;
            continue;
        }
        const QString key = QString::fromLatin1(kDefaults[i].name);
        if (settings.contains(key))
            m_bindings[i].key = QKeySequence(settings.value(key).toString());
        else
            m_bindings[i].key = kDefaults[i].defaultKey;
    }
    settings.endGroup();
}

void ShortcutManager::save(QSettings &settings) const
{
    settings.beginGroup("shortcuts");
    for (int i = 0; i < ActionCount; ++i) {
        if (kDefaults[i].category == CatNotConfigurable)
            continue;
        const QString key = QString::fromLatin1(kDefaults[i].name);
        if (m_bindings[i].key == kDefaults[i].defaultKey)
            settings.remove(key); // only store non-defaults
        else
            settings.setValue(key, m_bindings[i].key.toString());
    }
    settings.endGroup();
}

QKeySequence ShortcutManager::defaultShortcut(Action action)
{
    if (action < 0 || action >= ActionCount)
        return {};
    return kDefaults[action].defaultKey;
}

QString ShortcutManager::actionName(Action action)
{
    if (action < 0 || action >= ActionCount)
        return {};
    return QString::fromLatin1(kDefaults[action].name);
}

QString ShortcutManager::actionDescription(Action action)
{
    if (action < 0 || action >= ActionCount)
        return {};
    return QCoreApplication::translate("ShortcutManager", kDefaults[action].description);
}

ShortcutManager::Category ShortcutManager::actionCategory(Action action)
{
    if (action < 0 || action >= ActionCount)
        return CatNotConfigurable;
    return kDefaults[action].category;
}

bool ShortcutManager::matches(const QKeyEvent *event, Action action) const
{
    if (action < 0 || action >= ActionCount)
        return false;
    const QKeySequence &seq = m_bindings[action].key;
    if (seq.isEmpty())
        return false;
    // Compare the first key in the sequence against the event's key + modifiers.
    int eventKey = event->key();
    Qt::KeyboardModifiers mods = event->modifiers() & ~Qt::KeypadModifier;
    if (mods != Qt::NoModifier)
        eventKey |= mods;
    return seq[0] == QKeyCombination::fromCombined(eventKey);
}