#include "Virtual_Keyboard.h"
#include <QApplication>
#include <QDesktopWidget>
#include <QScreen>
namespace renderive {
Key_Button::Key_Button() {
    /*支持长按*/
    //        this->setAutoRepeat(true);
    //        this->setAutoRepeatDelay(500);
    //        this->setAutoRepeatInterval(100);
    connect(this, &QPushButton::pressed, [&]() {
        virtual_keyboard->handle_Key_Press(this);
    });
}
Virtual_Keyboard::Virtual_Keyboard(QWidget* parent) : QWidget(parent) {
    this->setStyleSheet(
        "QPushButton{"
        "font: 16pt 黑体;"
        "font-size: 26px;"
        "color: white;"
        "margin: 2px;"
        "border-radius: 5px;"
        "background: #00C78C;}"
        "QPushButton:pressed{"
        "background: #F0FFFF ;}"
        "QListWidget::Item:hover { background: #00C78C; color: white; }"
        "QListWidget {outline: none; border:1px solid #00000000; color: black; }"
        "QLineEdit {outline: none; border:1px solid #00000000; color: black;}");
    QSize screen_size = QGuiApplication::primaryScreen()->size();
    resize(screen_size / 2);
    main_layout = new QVBoxLayout(this);
    size_policy.setHorizontalPolicy(QSizePolicy::Preferred);
    size_policy.setVerticalPolicy(QSizePolicy::Preferred);
    size_policy.setHorizontalStretch(1);
    size_policy.setVerticalStretch(0);
    english = create_english();
    chinese = create_chinese();
    symbol = create_symbol();
    main_layout->addWidget(english);
    main_layout->addWidget(chinese);
    main_layout->addWidget(symbol);
    cur_widget = english;
    chinese->hide();
    symbol->hide();
    setWindowFlags(Qt::FramelessWindowHint | Qt::WindowStaysOnTopHint | Qt::Tool | Qt::WindowDoesNotAcceptFocus);
    core = new Input_Core(this);
    if (!core->init()) {
        qDebug() << "字典加载失败，请将dict文件移至工作目录";
    }
    /* 设置为列表显示模式 */
    list_widget->setViewMode(QListView::ListMode);
    /* 从左往右排列 */
    list_widget->setFlow(QListView::LeftToRight);
    /* 屏蔽水平滑动条 */
    list_widget->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    /* 屏蔽垂直滑动条 */
    list_widget->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    /* 设置为像素滚动 */
    list_widget->setHorizontalScrollMode(QListWidget::ScrollPerPixel);
    /* 设置鼠标左键拖动 */
    QScroller::grabGesture(list_widget, QScroller::LeftMouseButtonGesture);
    // 设置不可选中
    connect(edit, &QLineEdit::selectionChanged, [=] {
        edit->deselect();
    });
    // 中文输入
    connect(edit, &QLineEdit::textChanged, [=](const QString& text) {
        /* 单个字符过长引发崩溃
         * 处理：单个字符限制长度为10
         */
        if (text.isEmpty()) {
            return;
        }
        if (text.length() >= 10) {
            if (is_single_char(text)) {
                QString deal_text = text.mid(0, 10);
                get_candidate_list(deal_text);
                return;
            }
            get_candidate_list(text);
            return;
        }
        else {
            get_candidate_list(text);
        }
    });
    connect(list_widget, &QListWidget::itemClicked, [=](QListWidgetItem* item) {
        QKeyEvent key_press(QEvent::KeyPress, Qt::Key_unknown, Qt::NoModifier, item->text());
        QCoreApplication::sendEvent(input_widget, &key_press);
        list_widget->clear();
        edit->clear();
    });
}
Virtual_Keyboard::~Virtual_Keyboard() {}
bool Virtual_Keyboard::is_single_char(QString spell) {
    bool ret = true;
    for (auto s : spell) {
        if (s != spell[0]) {
            ret = false;
            break;
        }
    }
    return ret;
}
void Virtual_Keyboard::set_edit(QWidget* edit) {
    this->input_widget = edit;
    this->input_widget->installEventFilter(this);
}
void Virtual_Keyboard::get_candidate_list(const QString spell) {
    unsigned int cand = core->search(spell);
    if (cand == 0) {
        return;
    }
    std::vector<QString> ret = core->get_candidate(cand);
    if (ret.empty()) {
        return;
    }
    list_widget->clear();
    for (const QString& candidate : ret)
        list_widget->addItem(candidate);
}
void Virtual_Keyboard::handle_Key_Press(Key_Button* button) {
    if (state == Chinese) {
        if (button->key != Qt::Key_Backspace) {
            edit->insert(button->text);
        }
        else {
            if (!edit->text().isEmpty()) {
                edit->backspace();
            }
            else {
                list_widget->clear();
                QKeyEvent key_press(QEvent::KeyPress, button->key, button->modifiers, button->text);
                QCoreApplication::sendEvent(input_widget, &key_press);
            }
        }
    }
    else {
        if (button->is_text) {
            QKeyEvent key_press(QEvent::KeyPress, button->key, button->modifiers, button->text);
            if (input_widget) {
                QCoreApplication::sendEvent(input_widget, &key_press);
            }
            else {
                qWarning("VirtualKeyBoard input_widget == NULL!");
            }
        }
    }
}
bool Virtual_Keyboard::eventFilter(QObject* watched, QEvent* event) {
    bool ok = false;
    if (QApplication::focusWidget() == watched && event->type() == QEvent::MouseButtonRelease) {
        ok = true;
    }
    if (event->type() == QEvent::FocusIn) {
        ok = true;
    }
    if (ok) {
        QWidget* w = qobject_cast<QWidget*>(watched);
        set_edit(w);
        QPoint pos = w->mapToGlobal(QPoint(0, 0));
        QSize screen_size = QGuiApplication::primaryScreen()->size();
        int keyboard_width = width();
        int keyboard_height = height();
        int screen_width = screen_size.width();
        int screen_height = screen_size.height();
        int x = pos.x();
        int y = pos.y() + w->height();
        if (x + keyboard_width > screen_width) {
            setFixedWidth(screen_width - pos.x() - w->width());
        }
        if (y + keyboard_height > screen_height) {
            setFixedHeight(screen_height - pos.y() - w->height());
        }
        move(x, y);
        show();
    }
    if (event->type() == QEvent::FocusOut) {
        this->hide();
    }
    return QObject::eventFilter(watched, event);
}
void Virtual_Keyboard::mousePressEvent(QMouseEvent* event) {
    if (moving)
        return;
    if (event->button() == Qt::LeftButton) {
        moving = true;
        start_pos = pos();
        start_global_pos = event->globalPos();
        QApplication::setOverrideCursor(Qt::ClosedHandCursor);
    }
    event->accept();
}
void Virtual_Keyboard::mouseMoveEvent(QMouseEvent* event) {
    if (!moving)
        return;
    move(start_pos + event->globalPos() - start_global_pos);
    event->accept();
}
void Virtual_Keyboard::mouseReleaseEvent(QMouseEvent* event) {
    if (!moving)
        return;
    moving = false;
    event->accept();
    QApplication::restoreOverrideCursor();
}
} // namespace renderive