#include "login/LoginWindow.hpp"

#include <QColor>
#include <QFont>
#include <QHBoxLayout>
#include <QLabel>
#include <QLineEdit>
#include <QPainter>
#include <QPen>
#include <QPixmap>
#include <QPushButton>
#include <QRandomGenerator>
#include <QVBoxLayout>
#include <QWidget>

#include "AuthService.hpp"

namespace geopro::app {

namespace {

// 验证码图尺寸（约 120x40）。
constexpr int kCaptchaWidth = 120;
constexpr int kCaptchaHeight = 40;
constexpr int kNoiseLines = 6;

QColor randomDark(QRandomGenerator* rng)
{
    return QColor(rng->bounded(30, 160), rng->bounded(30, 160), rng->bounded(30, 160));
}

// 把验证码字符串画成一张模拟验证码图：随机颜色字符 + 干扰线。
QPixmap renderCaptchaPixmap(const QString& code)
{
    QPixmap pix(kCaptchaWidth, kCaptchaHeight);
    pix.fill(QColor("#EEF2FB"));

    QPainter p(&pix);
    p.setRenderHint(QPainter::Antialiasing, true);

    auto* rng = QRandomGenerator::global();

    // 干扰线
    for (int i = 0; i < kNoiseLines; ++i) {
        QColor c = randomDark(rng);
        c.setAlpha(120);
        p.setPen(QPen(c, 1));
        p.drawLine(rng->bounded(kCaptchaWidth), rng->bounded(kCaptchaHeight),
                   rng->bounded(kCaptchaWidth), rng->bounded(kCaptchaHeight));
    }

    // 逐字符绘制，轻微旋转 + 随机颜色
    const int n = code.isEmpty() ? 0 : code.size();
    const int slot = n > 0 ? kCaptchaWidth / (n + 1) : kCaptchaWidth;
    QFont font;
    font.setBold(true);
    font.setPixelSize(26);
    for (int i = 0; i < n; ++i) {
        p.save();
        const int x = slot * (i + 1) - 6;
        const int y = kCaptchaHeight / 2 + 4;
        p.translate(x, y);
        p.rotate(rng->bounded(-25, 25));
        font.setPixelSize(rng->bounded(22, 30));
        p.setFont(font);
        p.setPen(randomDark(rng));
        p.drawText(0, 0, QString(code.at(i)));
        p.restore();
    }
    p.end();
    return pix;
}

}  // namespace

LoginWindow::LoginWindow(geopro::net::AuthService& auth, QWidget* parent)
    : QDialog(parent), auth_(auth)
{
    setWindowTitle(QStringLiteral("Geopro 3.0 登录"));
    setFixedSize(400, 500);

    // 仅外观：登录窗自带样式（沿用全局主题令牌，保证一脉相承）。
    // QLineEdit 在所有状态都显式白底深字 + 边框，避免失焦时取调色板默认色与背景相近不可读。
    setStyleSheet(QStringLiteral(
        "QDialog { background: #F4F6FA; }"
        "#headerBand {"
        "  background: qlineargradient(x1:0, y1:0, x2:1, y2:1,"
        "    stop:0 #2D6CB5, stop:1 #234F87); }"
        "#brandTitle { color: #FFFFFF; font-size: 23px; font-weight: 700; }"
        "#brandSubtitle { color: rgba(255,255,255,0.82); font-size: 12px; }"
        "#fieldLabel { color: #5A6B85; font-size: 12px; font-weight: 600; }"
        "QLineEdit {"
        "  background: #FFFFFF; color: #1F2A3D;"
        "  border: 1px solid #C7D2E0; border-radius: 8px; padding: 0 12px;"
        "  selection-background-color: #2D6CB5; selection-color: #FFFFFF; }"
        "QLineEdit:focus { border: 1px solid #2D6CB5; }"
        "QLineEdit:disabled { background: #F0F2F6; color: #8A93A3; }"
        "#captchaImg { border: 1px solid #C7D2E0; border-radius: 8px; background: #EEF2FB; }"));

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

    // ── 品牌头部：强调色横幅 + 产品名 + 副标题（建立产品身份与视觉锚点）──
    auto* headerBand = new QWidget(this);
    headerBand->setObjectName(QStringLiteral("headerBand"));
    headerBand->setFixedHeight(108);
    auto* headerLayout = new QVBoxLayout(headerBand);
    headerLayout->setContentsMargins(32, 0, 32, 0);
    headerLayout->setSpacing(4);
    headerLayout->addStretch();
    auto* brandTitle = new QLabel(QStringLiteral("Geopro 3.0"), headerBand);
    brandTitle->setObjectName(QStringLiteral("brandTitle"));
    auto* brandSubtitle = new QLabel(QStringLiteral("地球物理数据分析平台"), headerBand);
    brandSubtitle->setObjectName(QStringLiteral("brandSubtitle"));
    headerLayout->addWidget(brandTitle);
    headerLayout->addWidget(brandSubtitle);
    headerLayout->addStretch();
    root->addWidget(headerBand);

    // ── 表单主体：标签在上、输入在下的纵向字段（现代、留白充分）──
    auto* body = new QWidget(this);
    auto* form = new QVBoxLayout(body);
    form->setContentsMargins(32, 24, 32, 26);
    form->setSpacing(6);

    // 统一字段构造：小号muted标签 + 40px 高输入框 + 字段间距。
    auto addField = [&](const QString& labelText, QLineEdit* edit) {
        auto* lbl = new QLabel(labelText, body);
        lbl->setObjectName(QStringLiteral("fieldLabel"));
        edit->setMinimumHeight(40);
        form->addWidget(lbl);
        form->addWidget(edit);
        form->addSpacing(6);
    };

    userEdit_ = new QLineEdit(body);
    userEdit_->setPlaceholderText(QStringLiteral("请输入用户名"));
    userEdit_->setClearButtonEnabled(true);
    addField(QStringLiteral("用户名"), userEdit_);

    pwdEdit_ = new QLineEdit(body);
    pwdEdit_->setEchoMode(QLineEdit::Password);
    pwdEdit_->setPlaceholderText(QStringLiteral("请输入密码"));
    addField(QStringLiteral("密码"), pwdEdit_);

    // 验证码：标签 + 一行（输入框占主，验证码图固定在右）。
    auto* codeLbl = new QLabel(QStringLiteral("验证码"), body);
    codeLbl->setObjectName(QStringLiteral("fieldLabel"));
    form->addWidget(codeLbl);

    auto* captchaRow = new QHBoxLayout();
    captchaRow->setSpacing(10);
    codeEdit_ = new QLineEdit(body);
    codeEdit_->setMinimumHeight(40);
    codeEdit_->setPlaceholderText(QStringLiteral("请输入验证码"));
    captchaLabel_ = new QLabel(body);
    captchaLabel_->setObjectName(QStringLiteral("captchaImg"));
    captchaLabel_->setFixedSize(kCaptchaWidth, kCaptchaHeight);
    captchaLabel_->setAlignment(Qt::AlignCenter);
    captchaRow->addWidget(codeEdit_, 1);
    captchaRow->addWidget(captchaLabel_);
    form->addLayout(captchaRow);

    // 刷新链接（右对齐，次要操作弱化为文字链接）。
    auto* refreshRow = new QHBoxLayout();
    refreshRow->addStretch();
    refreshBtn_ = new QPushButton(QStringLiteral("看不清？换一张"), body);
    refreshBtn_->setFlat(true);
    refreshBtn_->setCursor(Qt::PointingHandCursor);
    refreshBtn_->setStyleSheet(QStringLiteral(
        "QPushButton { color: #2D6CB5; border: none; background: transparent; padding: 2px 0; }"
        "QPushButton:hover { color: #234F87; text-decoration: underline; }"));
    refreshRow->addWidget(refreshBtn_);
    form->addLayout(refreshRow);

    // 错误提示：固定占位高度，避免出现时整体布局跳动。
    errorLabel_ = new QLabel(body);
    errorLabel_->setStyleSheet(QStringLiteral("color: #C0392B; font-size: 12px;"));
    errorLabel_->setWordWrap(true);
    errorLabel_->setMinimumHeight(18);
    form->addWidget(errorLabel_);

    form->addStretch();

    // 主操作：满宽强调主按钮（von Restorff：唯一高强调元素引导主流程）。
    loginBtn_ = new QPushButton(QStringLiteral("登 录"), body);
    loginBtn_->setMinimumHeight(44);
    loginBtn_->setCursor(Qt::PointingHandCursor);
    loginBtn_->setStyleSheet(QStringLiteral(
        "QPushButton { background: #2D6CB5; color: #FFFFFF; border: none; border-radius: 8px; "
        "font-size: 15px; font-weight: 600; }"
        "QPushButton:hover { background: #2862A6; }"
        "QPushButton:pressed { background: #234F87; }"
        "QPushButton:disabled { background: #9FB4CC; }"));
    loginBtn_->setDefault(true);
    form->addWidget(loginBtn_);

    root->addWidget(body, 1);

    connect(refreshBtn_, &QPushButton::clicked, this, &LoginWindow::refreshCaptcha);
    connect(loginBtn_, &QPushButton::clicked, this, &LoginWindow::attemptLogin);
    connect(codeEdit_, &QLineEdit::returnPressed, this, &LoginWindow::attemptLogin);
    connect(pwdEdit_, &QLineEdit::returnPressed, this, &LoginWindow::attemptLogin);

    refreshCaptcha();      // 打开即拉一张验证码
    userEdit_->setFocus(); // 焦点落在第一个待填字段
}

void LoginWindow::refreshCaptcha()
{
    codeEdit_->clear();
    try {
        const auto cap = auth_.fetchCaptcha();
        codeId_ = cap.codeId;
        captchaLabel_->setPixmap(renderCaptchaPixmap(cap.code));
    } catch (const std::exception& e) {
        showError(QStringLiteral("获取验证码失败：%1").arg(QString::fromUtf8(e.what())));
        captchaLabel_->setText(QStringLiteral("加载失败"));
    } catch (...) {
        showError(QStringLiteral("获取验证码失败"));
        captchaLabel_->setText(QStringLiteral("加载失败"));
    }
}

void LoginWindow::attemptLogin()
{
    const QString user = userEdit_->text().trimmed();
    const QString pwd = pwdEdit_->text();
    const QString code = codeEdit_->text().trimmed();

    if (user.isEmpty() || pwd.isEmpty() || code.isEmpty()) {
        showError(QStringLiteral("请填写用户名、密码和验证码"));
        return;
    }

    errorLabel_->clear();
    loginBtn_->setEnabled(false);
    const QString origText = loginBtn_->text();
    loginBtn_->setText(QStringLiteral("登录中..."));
    loginBtn_->repaint();  // 同步阻塞前刷新按钮文案

    geopro::net::AuthService::LoginResult result;
    try {
        result = auth_.login(user, pwd, code, codeId_);
    } catch (const std::exception& e) {
        result.ok = false;
        result.error = QStringLiteral("登录异常：%1").arg(QString::fromUtf8(e.what()));
    } catch (...) {
        result.ok = false;
        result.error = QStringLiteral("登录发生未知错误");
    }

    loginBtn_->setText(origText);
    loginBtn_->setEnabled(true);

    if (result.ok) {
        token_ = result.token;
        accept();
        return;
    }

    showError(result.error.isEmpty() ? QStringLiteral("登录失败") : result.error);
    refreshCaptcha();  // 失败刷新验证码
}

void LoginWindow::showError(const QString& msg)
{
    errorLabel_->setText(msg);
}

}  // namespace geopro::app