import { getRuntimePlatform } from './env';
import { ensureJssdkReady } from './jssdk';
import type { WeixinSdkConfig } from './types';

/** 调起扫码（返回二维码/条码内容，失败返回 null） */
export async function scanQrCode(config: WeixinSdkConfig): Promise<string | null> {
  const platform = getRuntimePlatform();

  if (platform === 'mini' && window.wx?.scanCode) {
    return new Promise((resolve) => {
      window.wx!.scanCode!({
        onlyFromCamera: true,
        scanType: ['qrCode', 'barCode'],
        success: (res) => resolve(res.result || null),
        fail: () => resolve(null),
      });
    });
  }

  if (platform === 'wechat-h5') {
    await ensureJssdkReady({
      apiBase: config.apiBase ?? '/api/v1',
      clientApp: config.clientApp,
      getAccessToken: config.getAccessToken,
    });
    if (!window.wx?.scanQRCode) {
      throw new Error('当前微信版本不支持扫码，请升级微信后重试');
    }
    return new Promise((resolve, reject) => {
      window.wx!.scanQRCode!({
        needResult: 1,
        scanType: ['qrCode', 'barCode'],
        success: (res) => resolve(res.resultStr || null),
        fail: (res) => {
          const msg = res.errMsg || '扫码失败';
          if (/cancel/i.test(msg)) {
            resolve(null);
            return;
          }
          if (/permission|auth|denied|授权|拒绝|camera/i.test(msg)) {
            reject(new Error('相机权限未开启，请在微信设置中允许使用摄像头'));
            return;
          }
          reject(new Error(msg));
        },
      });
    });
  }

  throw new Error('请在微信内打开以使用扫码核销');
}