// Type definitions for redux-pack 0.1
// Project: https://github.com/lelandrichardson/redux-pack
// Definitions by: tansongyang <https://github.com/tansongyang>
//                 dschuman <https://github.com/quicksnap>
//                 pweinberg <https://github.com/no-stack-dub-sack>
// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
// TypeScript Version: 2.4

import {
    Action as ReduxAction,
    Middleware,
    Reducer
} from 'redux';

export const KEY: {
    readonly LIFECYCLE: 'redux-pack/LIFECYCLE';
    readonly TRANSACTION: 'redux-pack/TRANSACTION';
};

export const LIFECYCLE: {
    readonly START: 'start';
    readonly SUCCESS: 'success';
    readonly FAILURE: 'failure';
};

export type LIFECYCLEValues = 'start' | 'succes' | 'failure';

export const middleware: Middleware;

// MetaPayload differs from ActionMeta in that it is the object that the reducers
// receive, instead of what is dispatched
export type MetaPayload<M> = M & {
    ['redux-pack/LIFECYCLE']?: LIFECYCLEValues;
    ['redux-pack/TRANSACTION']?: string;
};

// Incomplete typing
export type PackActionPayload<Payload, M> = ReduxAction & {
    payload: Payload;
    meta: MetaPayload<M>;
};

export type handlerReducer<S, A> = (state: S, action: A) => S;
export interface Handlers<S, TSuccessPayload, TErrorPayload, TStartPayload, TMetaPayload> {
    start?: handlerReducer<S, PackActionPayload<TStartPayload, TMetaPayload>>;
    finish?: handlerReducer<S, ReduxAction>;
    failure?: handlerReducer<S, PackActionPayload<TErrorPayload, TMetaPayload>>;
    success?: handlerReducer<S, PackActionPayload<TSuccessPayload, TMetaPayload>>;
    always?: handlerReducer<S, ReduxAction>;
}

export type GetState<S> = () => S;
export interface ActionMeta<TFullState = {}, TSuccessPayload = {}, TErrorPayload = {}, TStartPayload = {}> {
    startPayload?: TStartPayload;
    onStart?(payload: TStartPayload, getState: GetState<TFullState>): void;
    onFinish?(resolved: boolean, getState: GetState<TFullState>): void;
    onSuccess?(response: TSuccessPayload, getState: GetState<TFullState>): void;
    onFailure?(error: TErrorPayload, getState: GetState<TFullState>): void;
    ['redux-pack/LIFECYCLE']?: LIFECYCLEValues;
    ['redux-pack/TRANSACTION']?: string;
}

export interface PackError { error: boolean; payload: any; }
export interface Action<TFullState = {}, TSuccessPayload = {}, TErrorPayload = PackError, TStartPayload = {}, TMetaPayload = {}> extends ReduxAction {
    promise?: Promise<TSuccessPayload>;
    payload?: TSuccessPayload | TErrorPayload | TStartPayload;
    meta?: ActionMeta<TFullState, TSuccessPayload, TErrorPayload, TStartPayload> & TMetaPayload;
    // add optional error key to conform to FSA design: https://github.com/redux-utilities/flux-standard-action
    // note that users of this middleware (using our types) must conform to FSA shaped actions or code will not compile
    error?: boolean | null;
}

export interface TFullState { [key: string]: any; }
export function handle<TState, TSuccessPayload, TErrorPayload, TStartPayload, TMetaPayload>(
    state: TState,
    action: Action<TFullState, TSuccessPayload, TErrorPayload, TStartPayload, TMetaPayload>,
    handlers: Handlers<TState, TSuccessPayload, TErrorPayload, TStartPayload, TMetaPayload>,
): TState;