/**
 * QR码扫描器
 * @邠心vbe on 2026/04/21
 */
import React, { useEffect, useState } from 'react';
import { Pressable, StyleSheet, View } from 'react-native';
import TextView from '../../components/TextView';
import { Camera, useCameraDevice, useCodeScanner } from 'react-native-vision-camera';
import { check, PERMISSIONS, RESULTS } from 'react-native-permissions';
import utils from '../../utils/utils';

const checkPermission = (back) => {
  if (isIOS) {
    back(true);
  } else {
    check(PERMISSIONS.ANDROID.CAMERA).then(res => {
      console.log('checkPermission', res);
      switch (res) {
        case RESULTS.DENIED://权限未被请求/被拒绝，但可以请求
          back(false);
          break;
        case RESULTS.LIMITED://权限是有限的：有些操作是可能的
          back(true);
          break;
        case RESULTS.GRANTED://许可被授予
          back(true);
          break;
        case RESULTS.BLOCKED://权限被拒绝，不再可请求
          back(false);
          break;
        default:
          back(false);
          break;
      }
    }).catch(err => {
      back(false);
    })
  }
}

const QRScanner = ({ onResult, isActive }) => {
  const [flashOn, switchFlash] = useState(false);
  const [hasPermission, setHasPermission] = useState(false);
  const [permissionStr, setPermissionStr] = useState("");
  const device = useCameraDevice('back');
  useEffect(() => {
    console.log("相机设备", device);
    checkPermission(result => {
      setHasPermission(result);
    })
    Camera.requestCameraPermission().then(res => {
      setPermissionStr(res);
      utils.logEventTracking("scan_camera_permission", res)
      if (!hasPermission) {
        setHasPermission(res == 'granted');
      }
    }).catch(err => {
      console.warn("相机权限请求错误", err);
      utils.logEventTracking("scan_camera_permission_error", err)
    });
  }, []);
  const codeScanner = useCodeScanner({
    codeTypes: ['qr'],
    onCodeScanned: (codes) => {
      if (codes && codes.length > 0) {
        onResult(codes)
      }
    },
  });

  if (!device || !hasPermission) {
    return (
      <View style={styles.tipsScreen}>
        <TextView style={styles.tipsText}>
          {!hasPermission ? "Camera access has been denied. Please enable it in your device settings.(E0)" : "Can not find camera device.(E1)"}
        </TextView>
      </View>
    )
  }
  return (
    <>
      <Camera
        style={{width: $width, height: $vh(110)}}
        device={device}
        isActive={isActive}
        codeScanner={codeScanner}
        enableZoomGesture={true}
        photo={false}
        video={false}
        audio={false}
        resizeMode="cover"
        torch={flashOn ? 'on' : 'off'}
      />
      { isActive &&
        <Pressable
          style={styles.flashLight}
          onPress={() => switchFlash(!flashOn)}>
          <MaterialIcons
            name={flashOn ? "flashlight-on" : "flashlight-off"}
            size={36}
            color="#fff"/>
          <TextView style={{color: "#fff", fontSize: 12}}>{permissionStr}</TextView>
        </Pressable>
      }
    </>
  );
};

export default QRScanner;

const styles = StyleSheet.create({
  tipsScreen: {
    top: 0,
    left: 0,
    right: 0,
    bottom: 0,
    position: 'absolute',
    alignItems: "center",
    justifyContent: "center",
    backgroundColor: '#111',
  },
  tipsText: {
    color: textLight,
    fontSize: 14,
    textAlign: "center"
  },
  flashLight: {
    bottom: 120,
    zIndex: 2,
    opacity: 0.7,
    padding: 8,
    position: 'absolute'
  }
})