import type { WechatGpsLocation } from '@dukang/shared-types';
import { getRuntimePlatform, isWechatBrowser } from './env';
import { ensureJssdkReady } from './jssdk';
import type { WeixinSdkConfig } from './types';

export type WechatLocationOutcome = {
  sdk: 'jssdk' | 'geolocation';
  location: WechatGpsLocation | null;
  errMsg?: string;
};

/** 获取 GPS 定位（微信 JSSDK / 小程序优先，否则 H5 Geolocation） */
export async function getWechatLocation(config?: WeixinSdkConfig): Promise<WechatGpsLocation | null> {
  const outcome = await getWechatLocationDetailed(config);
  return outcome.location;
}

export async function getWechatLocationDetailed(
  config?: WeixinSdkConfig,
): Promise<WechatLocationOutcome> {
  const platform = getRuntimePlatform();

  if (platform === 'mini' && window.wx?.getLocation) {
    return new Promise((resolve) => {
      window.wx!.getLocation!({
        type: 'gcj02',
        success: (res) => resolve({ sdk: 'jssdk', location: res }),
        fail: (res) => resolve({ sdk: 'jssdk', location: null, errMsg: res.errMsg }),
      });
    });
  }

  if (platform === 'wechat-h5' && config) {
    try {
      await ensureJssdkReady({
        apiBase: config.apiBase ?? '/api/v1',
        clientApp: config.clientApp,
        getAccessToken: config.getAccessToken,
      });
      if (window.wx?.getLocation) {
        const jsApiOk = await new Promise<boolean>((resolve) => {
          window.wx!.checkJsApi?.({
            jsApiList: ['getLocation'],
            success: (res) => resolve(!!res.checkResult?.getLocation),
            fail: () => resolve(false),
          });
        });
        if (!jsApiOk) {
          return { sdk: 'jssdk', location: null, errMsg: 'getLocation 未授权或不可用' };
        }
        return new Promise((resolve) => {
          window.wx!.getLocation!({
            type: 'gcj02',
            success: (res) => resolve({ sdk: 'jssdk', location: res }),
            fail: (res) => resolve({ sdk: 'jssdk', location: null, errMsg: res.errMsg }),
          });
        });
      }
      return { sdk: 'jssdk', location: null, errMsg: '微信 JSSDK getLocation 不可用' };
    } catch (err) {
      const errMsg = err instanceof Error ? err.message : String(err);
      return { sdk: 'jssdk', location: null, errMsg };
    }
  }

  if (typeof navigator === 'undefined' || !navigator.geolocation) {
    return { sdk: 'geolocation', location: null, errMsg: '浏览器不支持定位' };
  }
  return new Promise((resolve) => {
    navigator.geolocation.getCurrentPosition(
      (pos) =>
        resolve({
          sdk: 'geolocation',
          location: {
            latitude: pos.coords.latitude,
            longitude: pos.coords.longitude,
            accuracy: pos.coords.accuracy,
          },
        }),
      (err) =>
        resolve({
          sdk: 'geolocation',
          location: null,
          errMsg: err.message || '定位失败',
        }),
      { enableHighAccuracy: false, timeout: 8000, maximumAge: 60_000 },
    );
  });
}

export function canUseWechatLocation(): boolean {
  return getRuntimePlatform() !== 'browser' || typeof navigator?.geolocation !== 'undefined';
}

export function isWechatEnv(): boolean {
  return isWechatBrowser() || getRuntimePlatform() === 'mini';
}