import React, { useEffect, useState, useRef } from "react";
import {
  Modal,
  View,
  Text,
  StyleSheet,
  TouchableOpacity,
  Image,
  ActivityIndicator,
} from "react-native";
import { generateQRCode, pollQRCode, getUserInfo } from "../services/bilibili";
import { useAuthStore } from "../store/authStore";

interface Props {
  visible: boolean;
  onClose: () => void;
}

export function LoginModal({ visible, onClose }: Props) {
  const [qrUrl, setQrUrl] = useState<string | null>(null);
  const [qrKey, setQrKey] = useState<string | null>(null);
  const [status, setStatus] = useState<
    "loading" | "waiting" | "scanned" | "done" | "error"
  >("loading");
  const pollRef = useRef<ReturnType<typeof setInterval> | null>(null);
  const login = useAuthStore((s) => s.login);
  const setProfile = useAuthStore((s) => s.setProfile);

  useEffect(() => {
    if (!visible) return;
    setStatus("loading");
    setQrUrl(null);
    setQrKey(null);
    generateQRCode()
      .then((data) => {
        setQrUrl(
          `https://api.qrserver.com/v1/create-qr-code/?data=${encodeURIComponent(data.url)}&size=200x200`,
        );
        setQrKey(data.qrcode_key);
        setStatus("waiting");
      })
      .catch(() => setStatus("error"));

    return () => {
      if (pollRef.current) clearInterval(pollRef.current);
    };
  }, [visible]);

  useEffect(() => {
    if (!qrKey || status !== "waiting") return;
    pollRef.current = setInterval(async () => {
      const result = await pollQRCode(qrKey);
      if (result.code === 86038) {
        setStatus("error");
        clearInterval(pollRef.current!);
      }
      if (result.code === 86090) setStatus("scanned");
      if (result.code === 0 && result.cookie) {
        clearInterval(pollRef.current!);
        try {
          await login(result.cookie, "", "");
          setStatus("done");
          // 登录后异步拉取用户头像和昵称
          const info = await getUserInfo();
          setProfile(info.face, info.uname, String(info.mid));
        } catch {
          setStatus("error");
        }
        onClose();
      }
    }, 2000);
    return () => {
      if (pollRef.current) clearInterval(pollRef.current);
    };
  }, [qrKey, status]);

  return (
    <Modal
      visible={visible}
      transparent
      animationType="none"
      onRequestClose={onClose}
    >
      <View style={styles.overlay}>
        <View style={styles.sheet}>
          <Text style={styles.title}>扫码登录</Text>
          {status === "loading" && (
            <ActivityIndicator
              size="large"
              color="#00AEEC"
              style={styles.loader}
            />
          )}
          {(status === "waiting" || status === "scanned") && qrUrl && (
            <>
              <Image source={{ uri: qrUrl }} style={styles.qr} />
              <Text style={styles.hint}>
                {status === "scanned"
                  ? "扫描成功，请在手机确认"
                  : "使用 B站 APP 扫一扫"}
              </Text>
            </>
          )}
          {status === "error" && (
            <Text style={styles.hint}>二维码已过期，请关闭重试</Text>
          )}
          <TouchableOpacity style={styles.closeBtn} onPress={onClose}>
            <Text style={styles.closeTxt}>关闭</Text>
          </TouchableOpacity>
        </View>
      </View>
    </Modal>
  );
}

const styles = StyleSheet.create({
  overlay: {
    flex: 1,
    backgroundColor: "rgba(0,0,0,0.5)",
    justifyContent: "flex-end",
  },
  sheet: {
    backgroundColor: "#fff",
    borderTopLeftRadius: 16,
    borderTopRightRadius: 16,
    padding: 24,
    alignItems: "center",
  },
  title: { fontSize: 18, fontWeight: "600", marginBottom: 20 },
  loader: { marginVertical: 40 },
  qr: { width: 200, height: 200, marginBottom: 12 },
  hint: { fontSize: 13, color: "#666", marginBottom: 20 },
  closeBtn: { padding: 12 },
  closeTxt: { fontSize: 14, color: "#00AEEC" },
});