/*
 * MIT License
 *
 * Copyright (c) 2018 Choko (choko@curioswitch.org)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

import { InjectableStore } from '../store';

import { DAEMON, ONCE_TILL_UNMOUNT, RESTART_ON_REMOUNT } from './constants';

interface Descriptor {
  saga: any;
  mode?: string;
}

function injectSagaFactory(store: InjectableStore) {
  return function injectsaga(
    key: string,
    descriptor: Descriptor,
    sagaArgs: any,
  ) {
    const newDescriptor = {
      ...descriptor,
      mode: descriptor.mode || RESTART_ON_REMOUNT,
    };
    const { saga, mode } = newDescriptor;

    let hasSaga = Reflect.has(store.injectedSagas, key);

    if (process.env.NODE_ENV !== 'production') {
      const oldDescriptor = store.injectedSagas[key];
      // enable hot reloading of daemon and once-till-unmount sagas
      if (hasSaga && oldDescriptor.saga !== saga) {
        oldDescriptor.task.cancel();
        hasSaga = false;
      }
    }

    if (
      !hasSaga ||
      (hasSaga && mode !== DAEMON && mode !== ONCE_TILL_UNMOUNT)
    ) {
      // eslint-disable-next-line no-param-reassign
      store.injectedSagas[key] = {
        ...newDescriptor,
        task: store.runSaga(saga, sagaArgs),
      };
    }
  };
}

export function ejectSagaFactory(store: InjectableStore) {
  return function ejectSaga(key: string) {
    if (Reflect.has(store.injectedSagas, key)) {
      const descriptor = store.injectedSagas[key];
      if (descriptor.mode !== DAEMON) {
        descriptor.task.cancel();
        // Clean up in production; in development we need `descriptor.saga` for hot reloading
        if (process.env.NODE_ENV === 'production') {
          // Need some value to be able to detect `ONCE_TILL_UNMOUNT` sagas in `injectSaga`
          // eslint-disable-next-line no-param-reassign
          store.injectedSagas[key] = 'done';
        }
      }
    }
  };
}

export default function getInjectors(store: InjectableStore) {
  return {
    injectSaga: injectSagaFactory(store),
    ejectSaga: ejectSagaFactory(store),
  };
}