let signin = document.querySelector('#signin');
let register = document.querySelector('#register');
let cartBtn = document.querySelector('#cart-btn');

let logRegisterInput = document.querySelector('#signup');
let passRegisterInput = document.querySelector('#signup-password');
let btnRegister = document.querySelector('#btn-register');

let loginInput = document.querySelector('#login');
let passwordInput = document.querySelector('#login-password');
let btnLogin = document.querySelector('#btn-login');

let overlay = document.querySelector(".overlay");
let registerForm = document.querySelector('#signup-form');
let loginForm = document.querySelector('#login-form');
let cartWrap = document.querySelector('#cart-wrap');
let dashboardWrap = document.querySelector('#dashboard-wrap');
let Closes = document.querySelectorAll(".close");

let registerWrap = document.querySelector("#register-wrap");
let userLogoutWrap = document.querySelector("#userlogout-wrap");
let user = document.querySelector("#user");

let dashboardUl = document.querySelector("#dashboard")
let cartUl = document.querySelector("#cart");
let btnBuy = document.querySelector("#btn-buy");

let logout = document.querySelector('#logout');
let dashboardBtn = document.querySelector('#dashboard-btn');

function showAndHideElem(element, value){
    element.style.display = value;
    overlay.style.display = value
}

signin.addEventListener("click", () => {
    showAndHideElem(loginForm, 'block');
});

register.addEventListener("click", () => {
    showAndHideElem(registerForm, 'block');
})

cartBtn.addEventListener("click", () => {
    showAndHideElem(cartWrap, 'block')
})

dashboardBtn.addEventListener("click", () => {
    showAndHideElem(dashboardWrap, 'block')
})

Closes[0].addEventListener("click", () => {
    showAndHideElem(registerForm, 'none');
    registerForm.reset();
})
Closes[1].addEventListener("click", () => {
    showAndHideElem(loginForm, 'none');
    loginForm.reset();
})
Closes[2].addEventListener("click", () => {
    showAndHideElem(cartWrap, 'none')
})

Closes[3].addEventListener("click", () => {
    showAndHideElem(dashboardWrap, 'none')
})



function createStore(reducer){                                     
    let state       = reducer(undefined, {}) 
    let cbs         = []                     
    
    const getState  = () => state            
    const subscribe = cb => (cbs.push(cb),   
                             () => cbs = cbs.filter(c => c !== cb)) 
                             
    const dispatch  = action => { 
        if (typeof action === 'function'){ 
            return action(dispatch, getState) 
        }
        const newState = reducer(state, action) 
        if (newState !== state){ 
            state = newState 
            for (let cb of cbs)  cb() 
        }
    }
    
    return {
        getState,
        dispatch,
        subscribe 
    }
}

const getGQL = url =>
    (query, variables) => fetch(url, {
        method: 'POST',
        headers: {
            "Content-Type": "application/json",
            // 'Accept' : 'application/json',
            ...(localStorage.authToken ? {"Authorization": "Bearer " + localStorage.authToken} : {})
        },
        body: JSON.stringify({query, variables})
    }).then(res => res.json())
        .then(data => {
            if (data.data){
                return Object.values(data.data)[0] 
            } 
            else throw new Error(JSON.stringify(data.errors))
        })
const backendURL = 'http://shop-roles.asmer.fs.a-level.com.ua'
const gql = getGQL(backendURL + '/graphql');

const jwtDecode = token => {
    try{
        return JSON.parse(atob(token.split('.')[1]));
        
    }
    catch(e){
        console.log(e.name, e.message);
    }
}

function promiseReducer(state={}, {type, name, status, payload, error}){
    if (type === 'PROMISE'){
        return {
            ...state,
            [name]:{status, payload, error}
        }
    }
    return state
}

function authReducer(state, {type, token}){                                 
    if (state === undefined){
        if(localStorage.authToken){
            type = 'AUTH_LOGIN';
            token = localStorage.authToken
        }
    }
    if(type === 'AUTH_LOGIN'){
        let payload = jwtDecode(token);
        if (payload){
            localStorage.authToken = token
             return {token, payload}
        }       
    } 
    if(type === 'AUTH_LOGOUT'){
        localStorage.removeItem("authToken")
        return {}
    } 
    return state || {}
}

const combineReducers = (reducers) => (state={}, action) => {
    let newState = {}
    for (const [reducerName, reducer] of Object.entries(reducers)){
            let subNewState = reducer(state[reducerName],action)
            if(subNewState !== state[reducerName]){
                newState = {
                    ...newState, [reducerName] : subNewState
                }
            }        
    }
    if(Object.keys(newState).length > 0){
            return {
                ...state,...newState
            }
    }
    return state
}

function cartReducer(state = {}, {type, good, count=1}){
    //каков state:
    //{
    //  _id1: {count:1, good: {_id1, name, price, images}}
    //  _id2: {count:1, good: {_id2, name, price, images}}
    //}
    //каковы действия по изменению state
    
    if (type === 'CART_ADD'){
        return {
            ...state,
            [good._id]: {count: count+(state[good._id]?.count || 0), good : good}
            //копируем старое и подменяем один ключ на новое, однако если
                    //ключ был, берем count из старого и прибавляем к count из action. 
        }
    }
    if (type === 'CART_CHANGE'){
        return { 
            ...state, 
            [good._id] : {count: count, good : good}
        //         ///!меняем полностью
        //         //копируем старое и подменяем один ключ на новое. аналогично ларьку
        //         //и promiseReducer
        }
    }
    if (type === 'CART_DELETE'){
        let {[good._id]: id1, ...newState} = state;
        return {
            ...newState
        }
        //смочь скопировать объект state без одного ключа 
        //(для этого есть хитрая деструктуризация, например
        //вернуть копию без этого ключа
    }
    if (type === 'CART_CLEAR'){
        return {}
    }
    return state
}

const actionCartAdd    = (good, count=1) => ({type: 'CART_ADD', good, count})
const actionCartChange = (good, count=1) => ({type: 'CART_CHANGE', good, count})             ///oninput меняяем полностью
const actionCartDelete = (good)          => ({type: 'CART_DELETE', good})
const actionCartClear  = ()              => ({type: 'CART_CLEAR'})



const store = createStore(combineReducers({promise: promiseReducer, auth: authReducer, cart: cartReducer}));
store.subscribe(() => console.log(store.getState()))

const actionAuthLogin = (token) => ({type: 'AUTH_LOGIN', token});
const actionAuthLogout = () => ({type: 'AUTH_LOGOUT'});

const actionPending             = name => ({type:'PROMISE',name, status: 'PENDING'})
const actionFulfilled = (name,payload) => ({type:'PROMISE',name, status: 'FULFILLED', payload})
const actionRejected  = (name,error)   => ({type:'PROMISE',name, status: 'REJECTED', error})
const actionPromise = (name, promise) =>
    async (dispatch) => {
        
        dispatch(actionPending(name))
        try {
            let payload = await promise;
            dispatch(actionFulfilled(name, payload));
            
            return payload
        }
        catch(error){
            dispatch(actionRejected(name, error))
        }
    }





const actionRootCats = () => 
    actionPromise('rootCats', gql(`query {
        CategoryFind(query: "[{\\"parent\\":null}]"){
            _id name
        }
    }`))

const actionCatById = (_id) =>  //добавить подкатегории
    actionPromise('catById', gql(`query catById($q: String){
        CategoryFindOne(query: $q){
            _id name subCategories {
                name _id
            }
            goods {
                _id name price images {
                    url
                }
            }
            
        }
    }`, {q: JSON.stringify([{_id}])}))

const actionGoodById = (_id) => 
    actionPromise('goodById', gql(`query goodByid($goodId: String) {
        GoodFindOne(query: $goodId) {
          name
          price
          description
          images {
            url
          }
        }
      }`, {goodId: JSON.stringify([{_id}])}))

const actionFullRegister = (log,  pass) => 
    async dispatch => {
        let user = await dispatch(
            actionPromise('register', gql( `mutation register($login: String, $password: String) {
                UserUpsert(user: {login: $login, password: $password}) {
                   _id
                   login
                 }
               }`, {login : log, password : pass}))
        )
        if(user){
            dispatch(actionFullLogin(log, pass));
        }
    }

const actionFullLogin = (log, pass) => 
      async dispatch => {
          let token = await dispatch(
            actionPromise('login', gql(`query login($login: String, $password: String) {
            login(login: $login, password: $password)
            }`, {login: log, password: pass}))
        )
        if(token){
            dispatch(actionAuthLogin(token))
        }
      }

const actionNewOrder = () => 
    async (dispatch, getState) => {
        const {cart} = getState();
        let order = {orderGoods : []}    
        for(let [key, value] of Object.entries(cart)){
            let newValue = {...value}
    
            let {name,price,images, ...id} = newValue.good;
            newValue.good = id;
            order.orderGoods.push({...newValue})
        }

        let newOrder = await dispatch(
            actionPromise('newOrder', gql(`mutation newOrder($order: OrderInput) {
                OrderUpsert(order: $order) {
                _id
                total
                }
            }`, {order: order}))
        )
        if(newOrder){
            dispatch(actionCartClear())
        }

    }

const actionOrders = () => 
actionPromise('orders', gql(`query findOrder($q: String) {
    OrderFind(query: $q) {
      _id
      total
      createdAt
      orderGoods {
        count
        good {
          name
          price
        }
      }
    }
  }`, {q: JSON.stringify([{}])}));

store.dispatch(actionRootCats())

store.subscribe(() => {
    const {rootCats} = store.getState().promise
    if (rootCats?.payload){
        aside.innerHTML = ''
        for (const {_id, name} of rootCats.payload){
            const link      = document.createElement('a')
            link.href       = `#/category/${_id}`
            link.innerText  = name
            aside.append(link)
        }
    }
})

window.onhashchange = () => {
    const [, route, _id] = location.hash.split('/');
    console.log()

    const routes = {
        category(){
            store.dispatch(actionCatById(_id));
            console.log('work')

        },
        good(){ //задиспатчить actionGoodById
            store.dispatch(actionGoodById(_id))
            
        },
        login(){
            //отрисовка тут
            btnLogin.onclick = (e) => {e.preventDefault() ;store.dispatch(actionFullLogin(loginInput.value, passwordInput.value))};
        },
        register(){
            btnRegister.onclick = (e) => {e.preventDefault(); store.dispatch(actionFullRegister(logRegisterInput.value, passRegisterInput.value))}
            
        },
        dashboard(){ //#/dashboard
             //задиспатчить actionOrders
            store.dispatch(actionOrders())
            console.log('заказостраница')
        }
        
    }
    if (route in routes)
        routes[route]()
}
window.onhashchange()


store.subscribe(() => {
    const {catById} = store.getState().promise
    const [,route, _id] = location.hash.split('/')                                           
    if (catById?.payload && route === 'category'){
        
        const {name, subCategories} = catById.payload 
        main.innerHTML = `<h1 class="category-name">${name}</h1>`
        if(subCategories){
            for(let {name, _id} of subCategories){
                const link      = document.createElement('a')
                link.href       = `#/category/${_id}`
                link.innerText  = name;
                main.append(link)
            }
        }
        for (const {_id, name, price, images} of catById.payload.goods){
            const card      = document.createElement('div')
            card.innerHTML = `<h2>${name}</h2>
                              <img src="${backendURL}/${images[0].url}" />
                              <strong>${price}</strong><br>
                              <a href="#/good/${_id}">посмотреть на ${name}</a>
                            `
            main.append(card);
            let btnAddToCart = document.createElement('button');
            btnAddToCart.classList.add('btn-buy');
            btnAddToCart.innerText = 'Добавить в корзину'
            card.append(btnAddToCart);
            btnAddToCart.onclick = () => store.dispatch(actionCartAdd({_id: _id, name: name, price: price, images: images}))
        }
    }
})

store.subscribe(() => {
    const {goodById} = store.getState().promise
    const [,route, _id] = location.hash.split('/') 
    if(goodById?.payload && route === 'good'){
        const {name, price, description, images} = goodById.payload;
        main.innerHTML = `<h1>${name}</h1>`
        const card = document.createElement('div');
        card.innerHTML = `<img src="${backendURL}/${images[0].url}" />
                          <strong>${price}</strong><br>
                          <div>${description}</div>
                          `
        main.append(card);
        let btnAddToCart = document.createElement('button');
            btnAddToCart.classList.add('btn-buy');
            btnAddToCart.innerText = 'Добавить в корзину'
            card.append(btnAddToCart);
            btnAddToCart.onclick = () => store.dispatch(actionCartAdd({_id: _id, name: name, price: price, images: images}))
    }
    //ТУТ ДОЛЖНА БЫТЬ ПРОВЕРКА НА НАЛИЧИЕ goodById в редакс
    //и проверка на то, что сейчас в адресной строке адрес ВИДА #/good/АЙДИ
    //в таком случае очищаем main и рисуем информацию про товар с подробностями
    //....А ТАК ЖЕ КНОПКА Купить, которая диспатчит actionCartAdd
})

store.subscribe(() => {           //если залогинен отрисовать юзернейм и кнопку логаут
    const {payload} = store.getState().auth
    if(payload?.sub){
        registerWrap.style.display = 'none';
        userLogoutWrap.style.display = 'block';
        const {login} = payload.sub;
        user.innerHTML = login;

    } else {
        registerWrap.style.display = 'block';
        userLogoutWrap.style.display = 'none';
    }
})

store.subscribe(() => {
    cartUl.innerHTML = ''
    const {cart} = store.getState();
    for (let value of Object.values(cart)){
        const {count, good} = value;
        const li = document.createElement("li");
        li.innerHTML = `<img src="${backendURL}/${good.images[0].url}"/>
                        <strong>${good.name}</strong>
                        <strong>${count}</strong>
                        `
        cartUl.append(li);
        const input = document.createElement("input");
        li.append(input);
        input.value = count
        input.oninput = () => store.dispatch(actionCartChange(good, +input.value));
        const button = document.createElement("button");
        button.innerText = 'удалить';
        li.append(button);
        button.onclick = () => store.dispatch(actionCartDelete(good))
    }
})

store.subscribe(() => {
    const {cart} = store.getState();
    Object.keys(cart).length > 0 ? 
        btnBuy.style.display='block' : 
        btnBuy.style.display='none';

    
    btnBuy.onclick = () => {
        store.dispatch(actionNewOrder());
    }
})


store.subscribe(() => {
    dashboardUl.innerHTML = ''
    const {orders} = store.getState().promise;
    const [,route, _id] = location.hash.split('/');
    if(orders?.payload && route === 'dashboard'){
        for(let {createdAt, total, orderGoods} of orders.payload){
            let date = new Date(+createdAt);
            let li = document.createElement("li");
            for(let {count, good} of orderGoods){
                let div = document.createElement("div");
                div.innerHTML = `<strong>${good.name}</strong>
                                <span>${count} &#10006; ${good.price}</span>
                                `
                li.append(div);
            }
            li.innerHTML += `<div>${total}</div>
            <div>${date.getDate()}.${date.getMonth() + 1}.${date.getFullYear()}</div>
            <hr>`
            dashboardUl.append(li)
        }
    }
    
})

logout.onclick = () => store.dispatch(actionAuthLogout() )