#include "qtkeyboard.h"
#include "ui_qtkeyboard.h"
#include <QDebug>
#include <QTimer>
#include <QDesktopWidget>

QKeyBoard* QKeyBoard::_instance = nullptr;
#define str_board_close "Close"
#define SHIFT_ON "SHIFT"
#define SHIFT_OFF "shift"

QKeyBoard::QKeyBoard(QWidget *parent) : QWidget(parent),
    ui(new Ui::QKeyBoard),
    isShiftOn(false),
    lineEdit(nullptr),
    mousePressed(false)
{
    ui->setupUi(this);
    ui->btna->setProperty("btnLetter", true);
    ui->btnb->setProperty("btnLetter", true);
    ui->btnc->setProperty("btnLetter", true);
    ui->btnd->setProperty("btnLetter", true);
    ui->btne->setProperty("btnLetter", true);
    ui->btnf->setProperty("btnLetter", true);
    ui->btng->setProperty("btnLetter", true);
    ui->btnh->setProperty("btnLetter", true);
    ui->btni->setProperty("btnLetter", true);
    ui->btnj->setProperty("btnLetter", true);
    ui->btnk->setProperty("btnLetter", true);
    ui->btnl->setProperty("btnLetter", true);
    ui->btnm->setProperty("btnLetter", true);
    ui->btnn->setProperty("btnLetter", true);
    ui->btno->setProperty("btnLetter", true);
    ui->btnp->setProperty("btnLetter", true);
    ui->btnq->setProperty("btnLetter", true);
    ui->btnr->setProperty("btnLetter", true);
    ui->btns->setProperty("btnLetter", true);
    ui->btnt->setProperty("btnLetter", true);
    ui->btnu->setProperty("btnLetter", true);
    ui->btnv->setProperty("btnLetter", true);
    ui->btnw->setProperty("btnLetter", true);
    ui->btnx->setProperty("btnLetter", true);
    ui->btny->setProperty("btnLetter", true);
    ui->btnz->setProperty("btnLetter", true);

    const QRect availableGeometry = QApplication::desktop()->availableGeometry();
    QFont font;
    font.setPixelSize(availableGeometry.height()/20);
    setWindowFlags(Qt::WindowStaysOnTopHint | Qt::FramelessWindowHint);
    connect(qApp, SIGNAL(focusChanged(QWidget*, QWidget*)),
            this, SLOT(slot_onApplicationFocusChanged(QWidget*, QWidget*)));
    qApp->installEventFilter(this);

    QList<QPushButton*> btns = this->findChildren<QPushButton*>();
    foreach (QPushButton *button, btns) {
        connect(button, SIGNAL(clicked()), this, SLOT(btn_clicked()));
        button->setFont(font);
    }
}

QKeyBoard::~QKeyBoard()
{
    delete ui;
    _instance = nullptr;
}

void QKeyBoard::changeInputType(bool on)
{
    QString str;
    ui->btnShift->setText(on?SHIFT_ON:SHIFT_OFF);
    QList<QPushButton*> buttons = this->findChildren<QPushButton*>();
    foreach (QPushButton *button, buttons) {
        if (button->property("btnLetter").toBool()) {
            if (on)
                button->setText(button->text().toUpper());
            else
                button->setText(button->text().toLower());
        } else if(! button->objectName().compare("btnApostrophe")){
            button->setText(on?"\"":"\'");
        } else if(! button->objectName().compare("btnBackslash")){
            button->setText(on?"|":"\\");
        } else if(! button->objectName().compare("btnComma")){
            button->setText(on?"<":",");
        } else if(! button->objectName().compare("btnDash")){
            button->setText(on?"_":"-");
        } else if(! button->objectName().compare("btnDot")){
            button->setText(on?">":".");
        } else if(! button->objectName().compare("btnEquals")){
            button->setText(on?"+":"=");
        } else if(! button->objectName().compare("btnSemicolon")){
            button->setText(on?":":";");
        } else if(! button->objectName().compare("btnSlash")){
            button->setText(on?"?":"/");
        } else if(! button->objectName().compare("btnOther1")){
            button->setText(on?"~":"`");
        } else if(! button->objectName().compare("btnOther2")){
            button->setText(on?"{":"[");
        } else if(! button->objectName().compare("btnOther3")){
            button->setText(on?"}":"]");
        } else if(! button->objectName().compare("btn1")){
            button->setText(on?"!":"1");
        } else if(! button->objectName().compare("btn2")){
            button->setText(on?"@":"2");
        } else if(! button->objectName().compare("btn3")){
            button->setText(on?"#":"3");
        } else if(! button->objectName().compare("btn4")){
            button->setText(on?"$":"4");
        } else if(! button->objectName().compare("btn5")){
            button->setText(on?"%":"5");
        } else if(! button->objectName().compare("btn6")){
            button->setText(on?"^":"6");
        } else if(! button->objectName().compare("btn7")){
            button->setText(on?"&":"7");
        } else if(! button->objectName().compare("btn8")){
            button->setText(on?"*":"8");
        } else if(! button->objectName().compare("btn9")){
            button->setText(on?"(":"9");
        } else if(! button->objectName().compare("btn0")){
            button->setText(on?")":"0");
        }
    }
}

void QKeyBoard::showPanel()
{
    changeInputType(isShiftOn);
    this->setVisible(true);
}

void QKeyBoard::hidePanel()
{
    this->setVisible(false);
}

void QKeyBoard::slot_onApplicationFocusChanged(QWidget *, QWidget *nowWidget)
{
    if (nowWidget != nullptr && !this->isAncestorOf(nowWidget)) {
        if (nowWidget->inherits("QLineEdit")) {
            lineEdit = (QLineEdit*)nowWidget;
            showPanel();
        } else {
            hidePanel();
        }

        const QRect availableGeometry = QApplication::desktop()->availableGeometry();
        resize(availableGeometry.width(), height());
        move(0, availableGeometry.height() - height());
    }
}

void QKeyBoard::btn_clicked()
{
    if (lineEdit == nullptr) {
        return;
    }

    QPushButton *button = (QPushButton*)sender();
    QString objectName = button->objectName();
    if (objectName == "btnBackspace") {
        lineEdit->backspace();
    } else if (objectName == "btnClose") {
        // foucs other widget first.
        if (lineEdit && lineEdit->parentWidget())
            lineEdit->parentWidget()->setFocus();
        hidePanel();
    } else if (objectName == "btnSpace") {
        insertValue(" ");
    } else if (objectName == "btnShift") {
        isShiftOn = (isShiftOn == true) ? false : true;
        changeInputType(isShiftOn);
    } else {
        insertValue(button->text());
    }
}

void QKeyBoard::insertValue(const QString &value)
{
    if (lineEdit->text().length() < 20)
        lineEdit->insert(value);
}

void QKeyBoard::mousePressEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        mousePressed = true;
        mousePoint = event->globalPos() - this->pos();
        event->accept();
    }
}

void QKeyBoard::mouseMoveEvent(QMouseEvent *event)
{
    if (mousePressed && event->buttons() == Qt::LeftButton) {
        this->move(event->globalPos() - mousePoint);
        event->accept();
    }
}

void QKeyBoard::mouseReleaseEvent(QMouseEvent *)
{
    mousePressed = false;
}