instrumental/app/javascript/mastodon/reducers/relationships.js

import {
  NOTIFICATIONS_UPDATE,
} from '../actions/notifications';
import {
  ACCOUNT_FOLLOW_SUCCESS,
  ACCOUNT_FOLLOW_REQUEST,
  ACCOUNT_FOLLOW_FAIL,
  ACCOUNT_UNFOLLOW_SUCCESS,
  ACCOUNT_UNFOLLOW_REQUEST,
  ACCOUNT_UNFOLLOW_FAIL,
  ACCOUNT_BLOCK_SUCCESS,
  ACCOUNT_UNBLOCK_SUCCESS,
  ACCOUNT_MUTE_SUCCESS,
  ACCOUNT_UNMUTE_SUCCESS,
  ACCOUNT_PIN_SUCCESS,
  ACCOUNT_UNPIN_SUCCESS,
  RELATIONSHIPS_FETCH_SUCCESS,
  FOLLOW_REQUEST_AUTHORIZE_SUCCESS,
  FOLLOW_REQUEST_REJECT_SUCCESS,
} from '../actions/accounts';
import {
  DOMAIN_BLOCK_SUCCESS,
  DOMAIN_UNBLOCK_SUCCESS,
} from '../actions/domain_blocks';
import {
  ACCOUNT_NOTE_SUBMIT_SUCCESS,
} from '../actions/account_notes';
import { Map as ImmutableMap, fromJS } from 'immutable';

const normalizeRelationship = (state, relationship) => state.set(relationship.id, fromJS(relationship));

const normalizeRelationships = (state, relationships) => {
  relationships.forEach(relationship => {
    state = normalizeRelationship(state, relationship);
  });

  return state;
};

const setDomainBlocking = (state, accounts, blocking) => {
  return state.withMutations(map => {
    accounts.forEach(id => {
      map.setIn([id, 'domain_blocking'], blocking);
    });
  });
};

const initialState = ImmutableMap();

export default function relationships(state = initialState, action) {
  switch(action.type) {
  case FOLLOW_REQUEST_AUTHORIZE_SUCCESS:
    return state.setIn([action.id, 'followed_by'], true).setIn([action.id, 'requested_by'], false);
  case FOLLOW_REQUEST_REJECT_SUCCESS:
    return state.setIn([action.id, 'followed_by'], false).setIn([action.id, 'requested_by'], false);
  case NOTIFICATIONS_UPDATE:
    return action.notification.type === 'follow_request' ? state.setIn([action.notification.account.id, 'requested_by'], true) : state;
  case ACCOUNT_FOLLOW_REQUEST:
    return state.getIn([action.id, 'following']) ? state : state.setIn([action.id, action.locked ? 'requested' : 'following'], true);
  case ACCOUNT_FOLLOW_FAIL:
    return state.setIn([action.id, action.locked ? 'requested' : 'following'], false);
  case ACCOUNT_UNFOLLOW_REQUEST:
    return state.setIn([action.id, 'following'], false);
  case ACCOUNT_UNFOLLOW_FAIL:
    return state.setIn([action.id, 'following'], true);
  case ACCOUNT_FOLLOW_SUCCESS:
  case ACCOUNT_UNFOLLOW_SUCCESS:
  case ACCOUNT_BLOCK_SUCCESS:
  case ACCOUNT_UNBLOCK_SUCCESS:
  case ACCOUNT_MUTE_SUCCESS:
  case ACCOUNT_UNMUTE_SUCCESS:
  case ACCOUNT_PIN_SUCCESS:
  case ACCOUNT_UNPIN_SUCCESS:
  case ACCOUNT_NOTE_SUBMIT_SUCCESS:
    return normalizeRelationship(state, action.relationship);
  case RELATIONSHIPS_FETCH_SUCCESS:
    return normalizeRelationships(state, action.relationships);
  case DOMAIN_BLOCK_SUCCESS:
    return setDomainBlocking(state, action.accounts, true);
  case DOMAIN_UNBLOCK_SUCCESS:
    return setDomainBlocking(state, action.accounts, false);
  default:
    return state;
  }
};