/**
 * Created by jimsugg on 9/26/16.
 */

import { combineReducers } from 'redux';
import { createSelector } from 'reselect';

import { BaDmId, TransitionType } from '../baDmDataTypes';
import { DmTransitionState } from '../baDmInterfaces';
import { DmInternal } from "../baDmClasses";
import { TransitionAction } from '../baDmActions'
import { NEW_SIGN, ADD_TRANSITION, UPDATE_TRANSITION, DELETE_TRANSITION } from "../baDmActions";

var _ = require('lodash/omit');

type DmState = DmInternal.DmState;
type DmTransitionMap = DmInternal.DmMap<DmTransitionState>;

// Return a simple object conforming to DmTransitionState
const createTransitionState =
    (id: BaDmId, name: string, eventId: BaDmId, targetMediaStateId: BaDmId, transitionType: TransitionType, conditionId: BaDmId) =>
        ({
            id: id,
            name: name,
            eventId: eventId,
            targetMediaStateId: targetMediaStateId,
            transitionType: transitionType,
            conditionId: conditionId
        });

const transitionsById = (state : DmTransitionMap = {}, {type, id, payload} : TransitionAction) => {
    switch (type) {
        case NEW_SIGN :
            return {};
        case ADD_TRANSITION :
            let {name, eventId, targetMediaStateId, type : transitionType, conditionId} = payload;
            return Object.assign({}, state, {[id]: createTransitionState(id, name, eventId, targetMediaStateId, transitionType, conditionId)});
        case UPDATE_TRANSITION :
            let updatedTransition = Object.assign({}, state[id], payload);
            return Object.assign({}, state, {[id]: updatedTransition});
        case DELETE_TRANSITION :
            return _.omit(state, id);
    }
    return state;
};

const transitionReducer = transitionsById;

export default transitionReducer;

// Selectors

export const getTransitionById = (state: DmState, props: any) => {
    let transitionState = state.transitions[props.id];
    return transitionState ? new DmInternal.Transition(transitionState) : undefined;
}

const getTransitionsById = (state: DmState) => state.transitions;

const getTransitionIdProp = (state: DmState, props : any) : string => <string>(props.id);

export const getTransitionsForEvent = createSelector<DmState, BaDmId[], DmTransitionMap, BaDmId> (
    getTransitionsById, getTransitionIdProp,
    (transitions, transitionId) => {
        return Object.keys(transitions).filter((id, index, idArray): boolean => transitions[id].id === transitionId);
    }
);