import { OrderedSet as ImmutableOrderedSet, Record as ImmutableRecord } from 'immutable';

import { ACCOUNT_BLOCK_SUCCESS, ACCOUNT_MUTE_SUCCESS } from 'soapbox/actions/accounts';
import { DOMAIN_BLOCK_SUCCESS } from 'soapbox/actions/domain_blocks';
import {
  SUGGESTIONS_FETCH_REQUEST,
  SUGGESTIONS_FETCH_SUCCESS,
  SUGGESTIONS_FETCH_FAIL,
  SUGGESTIONS_DISMISS,
  SUGGESTIONS_V2_FETCH_REQUEST,
  SUGGESTIONS_V2_FETCH_SUCCESS,
  SUGGESTIONS_V2_FETCH_FAIL,
  SUGGESTIONS_TRUTH_FETCH_SUCCESS,
} from 'soapbox/actions/suggestions';

import { SuggestedProfile } from '../actions/suggestions';

import type { AnyAction } from 'redux';
import type { APIEntity } from 'soapbox/types/entities';

const SuggestionRecord = ImmutableRecord({
  source: '',
  account: '',
});

const ReducerRecord = ImmutableRecord({
  items: ImmutableOrderedSet<Suggestion>(),
  next: null as string | null,
  isLoading: false,
});

type State = ReturnType<typeof ReducerRecord>;
type Suggestion = ReturnType<typeof SuggestionRecord>;
type APIEntities = Array<APIEntity>;

// Convert a v1 account into a v2 suggestion
const accountToSuggestion = (account: APIEntity) => {
  return {
    source: 'past_interactions',
    account: account.id,
  };
};

const importAccounts = (state: State, accounts: APIEntities) => {
  return state.withMutations(state => {
    state.set('items', ImmutableOrderedSet(accounts.map(accountToSuggestion).map(suggestion => SuggestionRecord(suggestion))));
    state.set('isLoading', false);
  });
};

const importSuggestions = (state: State, suggestions: APIEntities, next: string | null) => {
  return state.withMutations(state => {
    state.update('items', items => items.concat(suggestions.map(x => ({ ...x, account: x.account.id })).map(suggestion => SuggestionRecord(suggestion))));
    state.set('isLoading', false);
    state.set('next', next);
  });
};

const importTruthSuggestions = (state: State, suggestions: SuggestedProfile[], next: string | null) => {
  return state.withMutations(state => {
    state.update('items', items => items.concat(suggestions.map(x => ({ ...x, account: x.account_id })).map(suggestion => SuggestionRecord(suggestion))));
    state.set('isLoading', false);
    state.set('next', next);
  });
};

const dismissAccount = (state: State, accountId: string) => {
  return state.update('items', items => items.filterNot(item => item.account === accountId));
};

const dismissAccounts = (state: State, accountIds: Array<string>) => {
  return state.update('items', items => items.filterNot(item => accountIds.includes(item.account)));
};

export default function suggestionsReducer(state: State = ReducerRecord(), action: AnyAction) {
  switch (action.type) {
    case SUGGESTIONS_FETCH_REQUEST:
    case SUGGESTIONS_V2_FETCH_REQUEST:
      return state.set('isLoading', true);
    case SUGGESTIONS_FETCH_SUCCESS:
      return importAccounts(state, action.accounts);
    case SUGGESTIONS_V2_FETCH_SUCCESS:
      return importSuggestions(state, action.suggestions, action.next);
    case SUGGESTIONS_TRUTH_FETCH_SUCCESS:
      return importTruthSuggestions(state, action.suggestions, action.next);
    case SUGGESTIONS_FETCH_FAIL:
    case SUGGESTIONS_V2_FETCH_FAIL:
      return state.set('isLoading', false);
    case SUGGESTIONS_DISMISS:
      return dismissAccount(state, action.id);
    case ACCOUNT_BLOCK_SUCCESS:
    case ACCOUNT_MUTE_SUCCESS:
      return dismissAccount(state, action.relationship.id);
    case DOMAIN_BLOCK_SUCCESS:
      return dismissAccounts(state, action.accounts);
    default:
      return state;
  }
}