import _ from 'lodash';

import { Reducer, useMemo, useReducer } from 'react';

interface ActionArgMap<A> {

[type: string]: (...args: any[]) => Omit<A, 'type'> | null;

}

interface ActionMap<A> {

[type: string]: (...args: any[]) => A;

}

export let useModel = <S, A extends { type: string }>(

reducer: Reducer<S, A>,

initialState: S,

_actions: ActionArgMap<A>

) => {

let [state, dispatch] = useReducer<Reducer<S, A>>(reducer, initialState);

let actions = useMemo<ActionMap<A>>(() => {

return _.reduce(

_actions,

(acc, func, k) => {

acc[k] = (...args: any[]) => {

let patch = func(...args);

let action = { type: k, ...patch } as A;

return dispatch(action);

};

return acc;

},

Object.create(null)

);

}, [_actions, dispatch]);

return [state, actions];

};