// @flow
import { combineReducers } from 'redux';

import {
  ERROR,
  SET_CLIENT,
  SET_OAUTH,
  SET_OAUTH_RESULT,
  SET_SCOPES,
  SET_LOADING_STATE,
  REQUIRE_PERMISSIONS_ACCEPT,
  SET_CREDENTIALS,
  SET_SWITCHER,
} from './actions';

type Credentials = {
  login?: string,
  password?: string,
  rememberMe?: boolean,
  returnUrl?: string,
  isRelogin?: boolean,
  isTotpRequired?: boolean,
};

export default combineReducers<_, { action: string, payload?: mixed }>({
  credentials,
  error,
  isLoading,
  isSwitcherEnabled,
  client,
  oauth,
  scopes,
});

function error(state = null, { type, payload = null, error = false }) {
  switch (type) {
    case ERROR:
      if (!error) {
        throw new Error('Expected payload with error');
      }

      return payload;

    default:
      return state;
  }
}

function credentials(
  state = {},
  {
    type,
    payload,
  }: {
    type: string,
    payload: ?Credentials,
  },
) {
  if (type === SET_CREDENTIALS) {
    if (payload && typeof payload === 'object') {
      return {
        ...payload,
      };
    }

    return {};
  }

  return state;
}

function isSwitcherEnabled(state = true, { type, payload = false }) {
  switch (type) {
    case SET_SWITCHER:
      if (typeof payload !== 'boolean') {
        throw new Error('Expected payload of boolean type');
      }

      return payload;

    default:
      return state;
  }
}

function isLoading(state = false, { type, payload = null }) {
  switch (type) {
    case SET_LOADING_STATE:
      return !!payload;

    default:
      return state;
  }
}

function client(state = null, { type, payload = {} }) {
  switch (type) {
    case SET_CLIENT:
      return {
        id: payload.id,
        name: payload.name,
        description: payload.description,
      };

    default:
      return state;
  }
}

function oauth(state = null, { type, payload = {} }) {
  switch (type) {
    case SET_OAUTH:
      return {
        clientId: payload.clientId,
        redirectUrl: payload.redirectUrl,
        responseType: payload.responseType,
        scope: payload.scope,
        prompt: payload.prompt,
        loginHint: payload.loginHint,
        state: payload.state,
      };

    case SET_OAUTH_RESULT:
      return {
        ...state,
        success: payload.success,
        code: payload.code,
        displayCode: payload.displayCode,
      };

    case REQUIRE_PERMISSIONS_ACCEPT:
      return {
        ...state,
        acceptRequired: true,
      };

    default:
      return state;
  }
}

function scopes(state = [], { type, payload = [] }) {
  switch (type) {
    case SET_SCOPES:
      return payload;

    default:
      return state;
  }
}

export function getLogin(state: Object): ?string {
  return state.auth.credentials.login || null;
}

export function getCredentials(state: Object): Credentials {
  return state.auth.credentials;
}