import { App, Button, Checkbox, Form, Input, Typography } from "antd";
import { LockOutlined, ReloadOutlined, SafetyOutlined, UserOutlined } from "@ant-design/icons";
import { useCallback, useEffect, useState } from "react";
import { useTranslation } from "react-i18next";
import { getCurrentUser, getOpenPlatformConfig, getSystemParamValue } from "@/api";
import { fetchCaptcha, login, type CaptchaResponse } from "@/api/auth";
import type { SysPlatformConfig } from "@/types";
import "./index.less";

const { Title, Text, Link } = Typography;

type LoginFormValues = {
  username: string;
  password: string;
  captchaCode?: string;
  remember?: boolean;
  tenantCode?: string;
};

export default function Login() {
  const { t } = useTranslation();
  const [captcha, setCaptcha] = useState<CaptchaResponse | null>(null);
  const [captchaEnabled, setCaptchaEnabled] = useState(true);
  const [loading, setLoading] = useState(false);
  const [platformConfig, setPlatformConfig] = useState<SysPlatformConfig | null>(null);
  const [form] = Form.useForm<LoginFormValues>();
  const { message } = App.useApp();

  const loadCaptcha = useCallback(async () => {
    if (!captchaEnabled) {
      return;
    }
    const data = await fetchCaptcha();
    setCaptcha(data);
  }, [captchaEnabled]);

  useEffect(() => {
    const init = async () => {
      try {
        const [captchaValue, config] = await Promise.all([
          getSystemParamValue("security.captcha.enabled", "true"),
          getOpenPlatformConfig()
        ]);
        setPlatformConfig(config);
        const enabled = captchaValue !== "false";
        setCaptchaEnabled(enabled);
        if (enabled) {
          await loadCaptcha();
        }
      } catch {
        setCaptchaEnabled(true);
        await loadCaptcha();
      }
    };
    init();
  }, [loadCaptcha]);

  useEffect(() => {
    const searchParams = new URLSearchParams(window.location.search);
    if (searchParams.get("timeout") === "1") {
      message.warning(t("login.loginTimeout"));
      window.history.replaceState({}, document.title, window.location.pathname);
    }
  }, [t]);

  const onFinish = async (values: LoginFormValues) => {
    setLoading(true);
    try {
      const data = await login({
        username: values.username,
        password: values.password,
        tenantCode: values.tenantCode,
        captchaId: captchaEnabled ? captcha?.captchaId : undefined,
        captchaCode: captchaEnabled ? values.captchaCode : undefined
      });

      localStorage.setItem("accessToken", data.accessToken);
      localStorage.setItem("refreshToken", data.refreshToken);
      localStorage.setItem("username", values.username);

      if (data.availableTenants) {
        localStorage.setItem("availableTenants", JSON.stringify(data.availableTenants));
        const payload = JSON.parse(atob(data.accessToken.split(".")[1]));
        localStorage.setItem("activeTenantId", String(payload.tenantId));
      }

      try {
        const profile = await getCurrentUser();
        sessionStorage.setItem("userProfile", JSON.stringify(profile));
        localStorage.setItem("displayName", profile.displayName || profile.username || values.username);
        localStorage.setItem("username", profile.username || values.username);
      } catch {
        sessionStorage.removeItem("userProfile");
        localStorage.removeItem("displayName");
      }

      message.success(t("common.success"));
      window.location.href = "/";
    } catch {
      if (captchaEnabled) {
        await loadCaptcha();
      }
    } finally {
      setLoading(false);
    }
  };

  const loginStyle = platformConfig?.loginBgUrl
    ? {
        backgroundImage: `url(${platformConfig.loginBgUrl})`,
        backgroundSize: "cover",
        backgroundPosition: "center",
        position: "relative" as const
      }
    : {};

  const leftStyle = platformConfig?.loginBgUrl
    ? {
        ...loginStyle,
        background: "rgba(255, 255, 255, 0.2)",
        backdropFilter: "blur(10px)"
      }
    : {};

  const rightStyle = platformConfig?.loginBgUrl
    ? {
        background: "rgba(255, 255, 255, 0.85)",
        backdropFilter: "blur(20px)"
      }
    : {};

  return (
    <div className="login-page" style={loginStyle}>
      <div className="login-left" style={leftStyle}>
        <div className="login-brand">
          <img src={platformConfig?.logoUrl || "/logo.svg"} alt="Logo" className="brand-logo-img" />
          <span className="brand-name">{platformConfig?.projectName || "UnisBase"}</span>
        </div>

        <div className="login-hero">
          <h1 className="hero-title">
            {t("login.heroTitle1")}
            <br />
            <span className="hero-accent">{t("login.heroTitle2")}</span>
            <br />
            {t("login.heroTitle3")}
          </h1>
          <p className="hero-desc">{platformConfig?.systemDescription || t("login.heroDesc")}</p>
        </div>

        <div className="login-left-footer">
          <div className="footer-item">{t("login.enterpriseSecurity")}</div>
          <div className="footer-divider" aria-hidden="true" />
          <div className="footer-item">{t("login.multiLang")}</div>
          {platformConfig?.icpInfo ? (
            <>
              <div className="footer-divider" aria-hidden="true" />
              <div className="footer-item">{platformConfig.icpInfo}</div>
            </>
          ) : null}
        </div>
      </div>

      <div className="login-right" style={rightStyle}>
        <div className="login-container">
          <div className="login-header">
            <Title level={2}>{t("login.welcome")}</Title>
            <Text type="secondary">{t("login.subtitle")}</Text>
          </div>

          <Form form={form} layout="vertical" onFinish={onFinish} className="login-form" requiredMark={false} autoComplete="off">
            <Form.Item name="username" rules={[{ required: true, message: t("login.username") }]}>
              <Input
                size="large"
                prefix={<UserOutlined className="text-gray-400" aria-hidden="true" />}
                placeholder={t("login.username")}
                autoComplete="username"
                spellCheck={false}
                aria-label={t("login.username")}
              />
            </Form.Item>

            <Form.Item name="password" rules={[{ required: true, message: t("login.password") }]}>
              <Input.Password
                size="large"
                prefix={<LockOutlined className="text-gray-400" aria-hidden="true" />}
                placeholder={t("login.password")}
                autoComplete="current-password"
                aria-label={t("login.password")}
              />
            </Form.Item>

            {captchaEnabled ? (
              <Form.Item name="captchaCode" rules={[{ required: true, message: t("login.captcha") }]}>
                <div className="captcha-wrapper">
                  <Input
                    size="large"
                    prefix={<SafetyOutlined className="text-gray-400" aria-hidden="true" />}
                    placeholder={t("login.captcha")}
                    maxLength={6}
                    aria-label={t("login.captcha")}
                  />
                  <Button
                    className="captcha-image-btn"
                    onClick={() => void loadCaptcha()}
                    icon={!captcha ? <ReloadOutlined spin /> : null}
                    aria-label="刷新验证码"
                  >
                    {captcha ? <img src={captcha.imageBase64} alt="验证码" /> : null}
                  </Button>
                </div>
              </Form.Item>
            ) : null}

            <div className="login-extra">
              <Form.Item name="remember" valuePropName="checked" noStyle>
                <Checkbox>{t("login.rememberMe")}</Checkbox>
              </Form.Item>
              <Link className="forgot-password">{t("login.forgotPassword")}</Link>
            </div>

            <Form.Item>
              <Button type="primary" htmlType="submit" loading={loading} block size="large" className="login-submit-btn">
                {loading ? t("login.loggingIn") : t("login.submit")}
              </Button>
            </Form.Item>
          </Form>

          <div className="login-footer">
            <Text type="secondary">
              {t("login.demoAccount")} <Text strong className="tabular-nums">admin</Text> / {t("login.password")}{" "}
              <Text strong className="tabular-nums">123456</Text>
            </Text>
          </div>
        </div>
      </div>
    </div>
  );
}