// @flow

import {NativeModules} from 'react-native';
const PermissionsIOS = NativeModules.ReactNativePermissions;

type Status = 'authorized' | 'denied' | 'restricted' | 'undetermined';
type Rationale = {title: string, message: string};
type CheckOptions = string | {type: string};
type RequestOptions = string | {type: string, rationale?: Rationale};

const permissionTypes = [
  'location',
  'camera',
  'microphone',
  'photo',
  'contacts',
  'event',
  'reminder',
  'bluetooth',
  'notification',
  'backgroundRefresh',
  'speechRecognition',
  'mediaLibrary',
  'motion',
];

const DEFAULTS = {
  location: 'whenInUse',
  notification: ['alert', 'badge', 'sound'],
};

class ReactNativePermissions {
  canOpenSettings: () => Promise<boolean> = () =>
    PermissionsIOS.canOpenSettings().then(result => !!result);

  openSettings: () => Promise<*> = () => PermissionsIOS.openSettings();

  getTypes: () => Array<string> = () => permissionTypes;

  check = (permission: string, options?: CheckOptions): Promise<Status> => {
    if (!permissionTypes.includes(permission)) {
      const error = new Error(
        `ReactNativePermissions: ${permission} is not a valid permission type on iOS`,
      );

      return Promise.reject(error);
    }

    let type;

    if (typeof options === 'string') {
      type = options;
    } else if (options && options.type) {
      type = options.type;
    }

    return PermissionsIOS.getPermissionStatus(
      permission,
      type || DEFAULTS[permission],
    );
  };

  request = (permission: string, options?: RequestOptions): Promise<Status> => {
    if (!permissionTypes.includes(permission)) {
      const error = new Error(
        `ReactNativePermissions: ${permission} is not a valid permission type on iOS`,
      );

      return Promise.reject(error);
    }

    if (permission == 'backgroundRefresh') {
      const error = new Error(
        'ReactNativePermissions: You cannot request backgroundRefresh',
      );

      return Promise.reject(error);
    }

    let type;

    if (typeof options === 'string') {
      type = options;
    } else if (options && options.type) {
      type = options.type;
    }

    return PermissionsIOS.requestPermission(
      permission,
      type || DEFAULTS[permission],
    );
  };

  checkMultiple = (permissions: Array<string>): Promise<{[string]: string}> =>
    Promise.all(permissions.map(permission => this.check(permission))).then(
      result =>
        result.reduce((acc, value, index) => {
          const name = permissions[index];
          acc[name] = value;
          return acc;
        }, {}),
    );
}

export default new ReactNativePermissions();