import * as optionAnswers from './option-answers.actions';
import * as optionAnswersUtil from './option-answers-util';
import { IOptionAnswersMap, IOptionAnswersMaps} from '../../models';
import {Injectable} from '@angular/core';
import {NgSurveyStore} from '../ng-survey.store';
import {CustomAction} from '../../models';

@Injectable()
export class OptionAnswersReducer {

  constructor(private _ngSurveyStore: NgSurveyStore) {
  }

  optionAnswersReducer(action: CustomAction) {
    const state: IOptionAnswersMaps = this._ngSurveyStore.dataStore.optionAnswers;

    switch (action.type) {
      case optionAnswers.OptionAnswersActionTypes.ADD_OPTION_ANSWERS_ACTION: {
        const { elementId } = action.payload;
        const prevOptionAnswers: IOptionAnswersMap = state.get(elementId);
        let newOptionAnswers: IOptionAnswersMap;

        if (!prevOptionAnswers) {
          newOptionAnswers = optionAnswersUtil.createNewOptionAnswersMap(elementId);
        } else {
          newOptionAnswers = optionAnswersUtil.addOptionAnswer(elementId, prevOptionAnswers);
        }

        state.set(elementId, newOptionAnswers);

        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.REMOVE_OPTION_ANSWERS_ACTION: {
        const { elementId, optionAnswerId } = action.payload;
        const prevOptionAnswers: IOptionAnswersMap = state.get(elementId);
        const newOptionAnswers: IOptionAnswersMap = optionAnswersUtil.removeOptionAnswer(optionAnswerId, prevOptionAnswers);

        state.set(elementId, newOptionAnswers);

        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.REMOVE_OPTION_ANSWERS_MAP_ACTION: {
        const { elementId } = action.payload;
        state.delete(elementId);
        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.REMOVE_OPTION_ANSWERS_MAPS_ACTION: {
        const { elementIds } = action.payload;
        elementIds.forEach(id => state.delete(id));
        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.ADD_OPTION_ANSWERS_VALUE_ACTION: {
        const { elementId, optionAnswerId, value } = action.payload;
        const prevOptionAnswers: IOptionAnswersMap = state.get(elementId);
        const newOptionAnswers: IOptionAnswersMap = optionAnswersUtil.addOptionAnswerValue(
          optionAnswerId, value, prevOptionAnswers
        );

        state.set(elementId, newOptionAnswers);

        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.UPDATE_OPTION_ANSWERS_PAGE_FLOW: {
        const { elementId, optionAnswerId, pageFlow } = action.payload;
        const prevOptionAnswers: IOptionAnswersMap = state.get(elementId);
        const newOptionAnswers: IOptionAnswersMap = optionAnswersUtil.updateOptionAnswerPageFlow(
          optionAnswerId, pageFlow, prevOptionAnswers
        );

        state.set(elementId, newOptionAnswers);

        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.DRAG_OPTION_ANSWERS_ACTION: {
        const { elementId, startIndex, endIndex } = action.payload;
        const prevOptionAnswers: IOptionAnswersMap = state.get(elementId);
        const newOptionAnswers: IOptionAnswersMap = optionAnswersUtil.dragOptionAnswer(startIndex, endIndex, prevOptionAnswers);

        state.set(elementId, newOptionAnswers);

        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.TOGGLE_IS_ACTIVE_OPTION_ANSWERS_ACTION: {
        const { elementId, isSaved } = action.payload;
        const prevOptionAnswers: IOptionAnswersMap = state.get(elementId);

        if (prevOptionAnswers) {
          const newOptionAnswers: IOptionAnswersMap = optionAnswersUtil.toggleIsActiveOptionAnswerValue(isSaved, prevOptionAnswers);
          state.set(elementId, newOptionAnswers);
        }

        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.RESET_OPTION_ANSWERS_STATE: {
        const { ngSurveyState } = action.payload;
        this._ngSurveyStore.updateOptionAnswers(ngSurveyState.optionAnswers);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.IMPORT_OPTION_ANSWERS_STATE: {
        const { ngSurveyState } = action.payload;
        this._ngSurveyStore.updateOptionAnswers(ngSurveyState.optionAnswers);
        break;
      }

      case optionAnswers.OptionAnswersActionTypes.IMPORT_OPTION_ANSWERS: {
        const { newOptionAnswers, elementId } = action.payload;

        state.set(elementId, newOptionAnswers);

        this._ngSurveyStore.updateOptionAnswers(state);
        break;
      }

      default: {
        return state;
      }
    }
  }
}