import { get } from 'lodash'
import { create, remove, get as apiGet } from 'pubsweet-client/src/helpers/api'

import { handleError } from './utils'

// constants
const REQUEST = 'authors/REQUEST'
const FAILURE = 'authors/FAILURE'
const SUCCESS = 'authors/SUCCESS'

// actions
export const authorRequest = () => ({
  type: REQUEST,
})

export const authorFailure = error => ({
  type: FAILURE,
  error,
})

export const authorSuccess = () => ({
  type: SUCCESS,
})

export const getAuthors = (collectionId, fragmentId) =>
  apiGet(`/collections/${collectionId}/fragments/${fragmentId}/users`)

export const addAuthor = (author, collectionId, fragmentId) => dispatch => {
  dispatch(authorRequest())
  return create(`/collections/${collectionId}/fragments/${fragmentId}/users`, {
    email: author.email,
    role: 'author',
    ...author,
  }).then(author => {
    dispatch(authorSuccess())
    return author
  }, handleError(authorFailure, dispatch))
}

export const deleteAuthor = (collectionId, fragmentId, userId) => dispatch => {
  dispatch(authorRequest())
  return remove(
    `/collections/${collectionId}/fragments/${fragmentId}/users/${userId}`,
  )
    .then(() => dispatch(authorSuccess()))
    .catch(handleError(authorFailure, dispatch))
}

// selectors
export const getFragmentAuthors = (state, fragmentId) =>
  get(state, `authors.${fragmentId}`, [])

export const getAuthorFetching = state =>
  get(state, 'authors.isFetching', false)
export const getAuthorError = state => get(state, 'authors.error', null)

const initialState = { isFetching: false, error: null }

export default (state = initialState, action) => {
  switch (action.type) {
    case 'UPDATE_FRAGMENT_REQUEST':
    case REQUEST:
      return {
        ...initialState,
        isFetching: true,
      }
    case 'UPDATE_FRAGMENT_FAILURE':
    case FAILURE:
      return {
        ...initialState,
        error: get(JSON.parse(get(action.error, 'response', {})), 'error'),
        isFetching: false,
      }
    case 'UPDATE_FRAGMENT_SUCCESS':
    case SUCCESS:
      return initialState
    default:
      return state
  }
}