import { useEffect, useMemo, useState } from 'react';
import type { ClientRuntimeConfig } from '@dukang/shared-types';
import { request } from '../lib/api';
import {
  buildTencentLocPickerUrl,
  parseTencentLocPickerMessage,
  type TencentPickedLocation,
} from '../lib/tencentLocPicker';

type Props = {
  open: boolean;
  onClose: () => void;
  onPick: (loc: TencentPickedLocation) => void;
  latitude?: number | null;
  longitude?: number | null;
};

let cachedKey: string | null | undefined;

async function loadTencentLbsKey(): Promise<string> {
  if (cachedKey) return cachedKey;
  const cfg = await request<ClientRuntimeConfig>('PARTNER_H5', '/common/client-config', {
    silent: true,
  });
  const key = (cfg.tencentLbsKey || '').trim();
  if (!key) {
    throw new Error('未配置腾讯位置服务 Key，请联系管理员在系统设置中配置');
  }
  cachedKey = key;
  return key;
}

export default function TencentLocPickerOverlay({
  open,
  onClose,
  onPick,
  latitude,
  longitude,
}: Props) {
  const [key, setKey] = useState<string | null>(cachedKey ?? null);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState('');

  useEffect(() => {
    if (!open) return;
    let cancelled = false;
    setError('');
    if (key) return;
    setLoading(true);
    void loadTencentLbsKey()
      .then((k) => {
        if (!cancelled) setKey(k);
      })
      .catch((e) => {
        if (!cancelled) setError(e instanceof Error ? e.message : '加载地图配置失败');
      })
      .finally(() => {
        if (!cancelled) setLoading(false);
      });
    return () => {
      cancelled = true;
    };
  }, [open, key]);

  useEffect(() => {
    if (!open) return;
    function onMessage(event: MessageEvent) {
      const picked = parseTencentLocPickerMessage(event.data);
      if (!picked) return;
      onPick(picked);
      onClose();
    }
    window.addEventListener('message', onMessage);
    return () => window.removeEventListener('message', onMessage);
  }, [open, onPick, onClose]);

  const src = useMemo(() => {
    if (!key) return '';
    return buildTencentLocPickerUrl(key, {
      latitude: latitude != null ? Number(latitude) : undefined,
      longitude: longitude != null ? Number(longitude) : undefined,
    });
  }, [key, latitude, longitude]);

  if (!open) return null;

  return (
    <div
      style={{
        position: 'fixed',
        inset: 0,
        zIndex: 1000,
        background: '#fff',
        display: 'flex',
        flexDirection: 'column',
      }}
    >
      <div
        style={{
          display: 'flex',
          alignItems: 'center',
          justifyContent: 'space-between',
          padding: '12px 16px',
          borderBottom: '1px solid rgba(0,0,0,0.06)',
          flexShrink: 0,
        }}
      >
        <button type="button" className="partner-btn-outline" style={{ padding: '6px 12px' }} onClick={onClose}>
          关闭
        </button>
        <span style={{ fontWeight: 600 }}>地图选点</span>
        <span style={{ width: 52 }} />
      </div>
      <div style={{ flex: 1, minHeight: 0, position: 'relative' }}>
        {loading ? (
          <p className="label-md text-muted" style={{ padding: 24, textAlign: 'center' }}>
            加载地图…
          </p>
        ) : error ? (
          <p className="label-md" style={{ padding: 24, color: 'var(--color-heritage-red, #a61d24)' }}>
            {error}
          </p>
        ) : src ? (
          <iframe
            title="腾讯地图选点"
            src={src}
            style={{ width: '100%', height: '100%', border: 0, display: 'block' }}
          />
        ) : null}
      </div>
    </div>
  );
}