#include "LoginWindow.h"
#include "RegisterDialog.h"
#include "ForgotPasswordDialog.h"
#include "ConfirmDialog.h"
#include "UiHelpers.h"
#include "TitleBar.h"
#include "FramelessHelper.h"
#include "UserSettings.h"
#include "AppConfig.h"
#include "ImClient.h"
#include "Protocol.h"
#include "Updater.h"

#include <QApplication>
#include <QCheckBox>
#include <QCloseEvent>
#include <QEasingCurve>
#include <QJsonObject>
#include <QLabel>
#include <QLineEdit>
#include <QPointer>
#include <QPropertyAnimation>
#include <QPushButton>
#include <QShowEvent>
#include <QStackedWidget>
#include <QTimer>
#include <QVBoxLayout>
#include <QHBoxLayout>

LoginWindow::LoginWindow(QWidget *parent)
    : QWidget(parent)
{
    setObjectName(QStringLiteral("ChromeWindow"));
    setWindowTitle(QStringLiteral("NIM"));
    setFixedSize(350, 400);
    setWindowFlags(Qt::Window | Qt::FramelessWindowHint);
    setWindowIcon(UiHelpers::appIcon());

    auto *root = new QVBoxLayout(this);
    root->setContentsMargins(0, 0, 0, 0);
    root->setSpacing(0);

    m_titleBar = new TitleBar(this);
    m_titleBar->setTitle(QStringLiteral("NIM"));
    m_titleBar->setTheme(TitleBar::Light);
    m_titleBar->setMaximizable(false);
    m_titleBar->bind(this, false);
    root->addWidget(m_titleBar);

    m_header = UiHelpers::authHeader(QStringLiteral("即时通讯"), this);
    root->addWidget(m_header);

    m_stack = new QStackedWidget(this);
    m_registerPage = new RegisterDialog(m_stack);
    m_resetPage = new ForgotPasswordDialog(m_stack);
    m_stack->addWidget(buildLoginPage());
    m_stack->addWidget(m_registerPage);
    m_stack->addWidget(m_resetPage);
    root->addWidget(m_stack, 1);

    connect(m_registerPage, &RegisterDialog::submitted, this, &LoginWindow::onRegisterSubmitted);
    connect(m_registerPage, &RegisterDialog::backRequested, this, [this]() { showPage(PageLogin); });
    connect(m_resetPage, &ForgotPasswordDialog::submitted, this, &LoginWindow::onResetSubmitted);
    connect(m_resetPage, &ForgotPasswordDialog::backRequested, this, [this]() { showPage(PageLogin); });

    applySavedLogin();
    connect(&ImClient::instance(), &ImClient::limitsUpdated, this, &LoginWindow::applyServerLimits);
    applyServerLimits();
    ImClient::instance().connectToServer();
    tryAutoLogin();
}

QWidget *LoginWindow::buildLoginPage()
{
    auto *form = new QWidget(this);
    auto *lay = new QVBoxLayout(form);
    lay->setContentsMargins(36, 28, 36, 28);
    lay->setSpacing(12);

    m_account = UiHelpers::lineEdit(QStringLiteral("账号"), form);
    m_password = UiHelpers::passwordEdit(QStringLiteral("密码"), form);

    auto *opts = new QHBoxLayout();
    opts->setContentsMargins(0, 2, 0, 0);
    m_remember = new QCheckBox(QStringLiteral("记住密码"), form);
    m_autoLogin = new QCheckBox(QStringLiteral("自动登录"), form);
    opts->addWidget(m_remember);
    opts->addStretch();
    opts->addWidget(m_autoLogin);

    m_error = UiHelpers::errorLabel(form);

    m_loginBtn = UiHelpers::primaryButton(QStringLiteral("登 录"), form);
    m_loginBtn->setMinimumWidth(0);

    auto *links = new QHBoxLayout();
    auto *reg = UiHelpers::linkButton(QStringLiteral("注册账号"), form);
    auto *forgot = UiHelpers::linkButton(QStringLiteral("忘记密码"), form);
    links->addWidget(reg);
    links->addStretch();
    links->addWidget(forgot);

    lay->addWidget(m_account);
    lay->addWidget(m_password);
    lay->addLayout(opts);
    lay->addWidget(m_error);
    lay->addSpacing(6);
    lay->addWidget(m_loginBtn);
    lay->addLayout(links);
    lay->addStretch();

    connect(m_loginBtn, &QPushButton::clicked, this, &LoginWindow::onLogin);
    connect(m_password, &QLineEdit::returnPressed, this, &LoginWindow::onLogin);
    connect(m_account, &QLineEdit::returnPressed, this, [this]() { m_password->setFocus(); });
    connect(reg, &QPushButton::clicked, this, [this]() { showPage(PageRegister); });
    connect(forgot, &QPushButton::clicked, this, [this]() { showPage(PageReset); });
    connect(m_autoLogin, &QCheckBox::toggled, this, [this](bool on) {
        if (on)
            m_remember->setChecked(true);
    });
    connect(m_remember, &QCheckBox::toggled, this, [this](bool on) {
        if (!on)
            m_autoLogin->setChecked(false);
    });

    return form;
}

void LoginWindow::showPage(Page page)
{
    m_stack->setCurrentIndex(page);
    switch (page)
    {
    case PageRegister:
        m_titleBar->setTitle(QStringLiteral("注册账号"));
        UiHelpers::setAuthHeaderSubtitle(m_header, QStringLiteral("创建你的账号"));
        m_registerPage->resetForm();
        animateToHeight(580);
        break;
    case PageReset:
        m_titleBar->setTitle(QStringLiteral("找回密码"));
        UiHelpers::setAuthHeaderSubtitle(m_header, QStringLiteral("重置登录密码"));
        m_resetPage->resetForm();
        animateToHeight(540);
        break;
    case PageLogin:
    default:
        m_titleBar->setTitle(QStringLiteral("NIM"));
        UiHelpers::setAuthHeaderSubtitle(m_header, QStringLiteral("即时通讯"));
        m_account->setFocus();
        animateToHeight(400);
        break;
    }
}

void LoginWindow::animateToHeight(int h)
{
    if (height() == h && minimumHeight() == h && maximumHeight() == h)
        return;
    if (m_heightAnim)
    {
        m_heightAnim->stop();
        m_heightAnim = nullptr;
    }

    setMinimumWidth(350);
    setMaximumWidth(350);
    setMinimumHeight(qMin(height(), h));
    setMaximumHeight(qMax(height(), h));

    auto *anim = new QPropertyAnimation(this, "geometry", this);
    anim->setDuration(220);
    anim->setEasingCurve(QEasingCurve::OutCubic);
    const QRect from = geometry();
    QRect to = from;
    to.setHeight(h);
    anim->setStartValue(from);
    anim->setEndValue(to);
    connect(anim, &QPropertyAnimation::finished, this, [this, h]() {
        setFixedSize(350, h);
        m_heightAnim = nullptr;
    });
    m_heightAnim = anim;
    anim->start(QAbstractAnimation::DeleteWhenStopped);
}

void LoginWindow::showEvent(QShowEvent *event)
{
    QWidget::showEvent(event);
    const int h = (m_stack && m_stack->currentIndex() == PageRegister) ? 580
                : (m_stack && m_stack->currentIndex() == PageReset) ? 540
                : 400;
    setFixedSize(350, h);
    if (m_titleBar && m_titleBar->framelessHelper())
        m_titleBar->framelessHelper()->fixupSize();
    QTimer::singleShot(0, this, [this, h]() {
        if (m_heightAnim)
            return;
        setFixedSize(350, h);
        if (m_titleBar && m_titleBar->framelessHelper())
            m_titleBar->framelessHelper()->fixupSize();
    });
}

void LoginWindow::closeEvent(QCloseEvent *event)
{
    QApplication::quit();
    QWidget::closeEvent(event);
}

QString LoginWindow::lastAccount() const
{
    return m_account ? m_account->text().trimmed() : QString();
}

void LoginWindow::prepareAfterLogout()
{
    m_skipAutoLogin = true;
    showPage(PageLogin);
}

void LoginWindow::showLogoutNotice(const QString &reason)
{
    if (reason.trimmed().isEmpty())
        return;
    const QString text = reason;
    QTimer::singleShot(280, this, [this, text]() {
        if (!isVisible())
            return;
        ConfirmDialog::notice(this, QStringLiteral("下线通知"), text);
    });
}

void LoginWindow::applySavedLogin()
{
    const auto &u = UserSettings::instance();
    m_account->setText(u.lastAccount());
    m_remember->setChecked(u.rememberPassword());
    m_autoLogin->setChecked(u.autoLogin());
    if (u.rememberPassword())
        m_password->setText(u.lastPassword());
    else
        m_password->clear();

    if (u.lastAccount().isEmpty())
        m_account->setFocus();
    else if (!u.rememberPassword() || u.lastPassword().isEmpty())
        m_password->setFocus();
}

void LoginWindow::applyServerLimits()
{
    const auto &cfg = AppConfig::instance();
    if (m_account && cfg.accountMax() > 0)
        m_account->setMaxLength(cfg.accountMax());
    if (m_password && cfg.passwordMax() > 0)
        m_password->setMaxLength(cfg.passwordMax());
    if (m_registerPage)
        m_registerPage->applyLimits();
    if (m_resetPage)
        m_resetPage->applyLimits();
    Updater::promptIfNeeded(this);
}

void LoginWindow::tryAutoLogin()
{
    if (m_skipAutoLogin)
        return;
    if (!willAutoLogin())
        return;
    QTimer::singleShot(0, this, &LoginWindow::onLogin);
}

bool LoginWindow::willAutoLogin() const
{
    if (m_skipAutoLogin)
        return false;
    const auto &u = UserSettings::instance();
    if (!u.autoLogin() || !u.rememberPassword())
        return false;
    if (!m_account || !m_password)
        return false;
    return !m_account->text().trimmed().isEmpty() && !m_password->text().isEmpty();
}

void LoginWindow::onLogin()
{
    if (m_loggingIn)
        return;
    UiHelpers::setError(m_error, QString());
    const QString account = m_account->text().trimmed();
    const QString password = m_password->text();
    if (account.isEmpty() || password.isEmpty())
    {
        UiHelpers::setError(m_error, QStringLiteral("请输入账号和密码"));
        return;
    }

    m_loggingIn = true;
    m_loginBtn->setEnabled(false);
    QPointer<LoginWindow> self(this);
    ImClient::instance().login(account, password, [self, account, password](const QJsonObject &reply) {
        if (!self)
            return;
        self->m_loggingIn = false;
        self->m_loginBtn->setEnabled(true);
        if (!ImClient::ok(reply))
        {
            UiHelpers::setError(self->m_error, ImClient::messageOf(reply));
            if (!self->isVisible())
            {
                self->show();
                self->raise();
                self->activateWindow();
            }
            return;
        }
        const QString nickname = reply.value(QStringLiteral("nickname")).toString();
        const QString savedAccount = reply.value(QStringLiteral("account")).toString();
        const QString acc = savedAccount.isEmpty() ? account : savedAccount;
        UserSettings::instance().saveLogin(acc,
                                           nickname.isEmpty() ? acc : nickname,
                                           password,
                                           self->m_remember->isChecked(),
                                           self->m_autoLogin->isChecked());
        emit self->loginSucceeded(acc, nickname.isEmpty() ? acc : nickname);
    });
}

void LoginWindow::onRegisterSubmitted(qint64 /*uid*/)
{
    m_account->setText(m_registerPage->account());
    m_password->clear();
    UiHelpers::setError(m_error, QString());
    showPage(PageLogin);
    m_password->setFocus();
    UiHelpers::showToast(this, QStringLiteral("注册成功，请使用账号登录"));
}

void LoginWindow::onResetSubmitted()
{
    m_password->clear();
    UiHelpers::setError(m_error, QString());
    showPage(PageLogin);
    m_password->setFocus();
    UiHelpers::showToast(this, QStringLiteral("密码已重置，请登录"));
}