import { Injectable } from '@angular/core';
import { ApiProvider } from '../../services/api/api.provider';
import { Subject } from 'rxjs/Subject';

import { Cart, CartItem } from './cart';
import { Product } from '../product/product';
import 'rxjs/add/operator/map';
import * as _ from 'lodash';


// Generated class for the ProductsService provider.
// See https://angular.io/docs/ts/latest/guide/dependency-injection.html
// for more info on providers and Angular 2 DI.
@Injectable()
export class CartsProvider {

  carts: Cart[];
  currentCart: Cart;
  // "broadcasting" currentCart
  cartObservable: Subject<Cart>;

  cartsObservable: Subject<Cart[]>;

  constructor( public apiProvider: ApiProvider) {
    this.carts = [];
    this.currentCart = Cart.fromJson(this.emptyCart());
    this.cartObservable = <Subject <Cart>> new Subject();
    this.cartsObservable = <Subject <Cart[]>> new Subject();

  }

  //
  cartState(result: Cart) {
    this.currentCart = result;
    this.cartObservable.next(this.currentCart);
    // TODO REMOVE need to check if a cart actually exists
    this.cartsObservable.next(this.carts);

  }

  emptyCart(tenantId?: any, storeId?: any) {
      let empty: any[];
      empty = [];
      return {
          '__v': '',
         'userId': '',
         'storeId': storeId,
         'tenantId': tenantId,
         'id': '',
         'created': '',
         'status': '',
         'items': empty,
         'numItems': 0,
         'total': 0
      };
  }

  // TODO storeiD?  tenatid?
  create(tenantId: string, storeId: string, userId: string) {
      let payload: any = {};
      // TODO REMOVE for demo only
      payload.storeId = storeId;
      payload.tenantId = tenantId;
      let promise = new Promise( (resolve, reject)  => {
      this.apiProvider.api('POST', '/v1/cart', payload)  // new ApiProvider(http).api('POST', '/v1/cart/', payload)
      .then((response: any) => {
          if (response.id) {
            // this.carts[response._id] = response;
            // this.cartState(response);
            this.update(tenantId, storeId, userId, response.id).then( (cart: Cart) => resolve(cart));
            // DO NOT DELETE, we are utilizing update to override the default userId on create
            // will need them in the future
            // const cart = Cart.fromJson(response);
            // this.carts.push(cart);
            // this.cartState(cart);
            // console.log('resolving');
            // resolve(cart);
          } else {
            reject('No id in cart create response!');

          }
        }, (err) => {
            // @todo: We should check for errors ?!?
            reject(err);
          });
        });
    return promise;
  }


  retrieve(cartId: string) {
    let payload = {};
    let promise = new Promise((resolve, reject) => {

      // let cart_temp =  this.carts.filter((item: Cart) => { return cartId  === item.id; });
      // if (cart_temp.length >0 ) resolve(cart_temp[0]);
      // else {
            this.apiProvider.api('GET', '/v1/cart/' + cartId, payload)
          .then((response: any) => {
            if (response.id) {
              const cart = Cart.fromJson(response);
              const position = this.carts.findIndex((item) => { return item.id === cart.id; });
              this.carts.splice(position, 1, cart);
              this.cartState(cart);
              resolve(cart);
            } else {
              reject();
            }
          },  (err) => { // catch error
            // @todo: We should check for errors ?!?
                reject(err);
              });
      // }
      });

    return promise;
  }

  // TODO add code
  retrieveAllCarts(tenantId?: string, storeId?: string) {
    let payload: any = {};
    if(tenantId) payload.tenantId = tenantId;
    if(storeId)  payload.storeId  = storeId;

        
    let promise = new Promise((resolve, reject) => {
      if(this.carts.length === 0){
        this.apiProvider.api('GET', '/v1/carts', payload)
        .then((response: any) => {
          if (response) {
          //  let cartsN: Cart[] = [];
          //   response.forEach((item: any) => {
          //      cartsN.push(Cart.fromJson(item));
          //   });
            this.carts = this.deserializeCarts(response);
            this.cartsObservable.next(this.carts);
            console.log('resolving');
            resolve(this.carts); // ??
          } else {
            reject();
          }
        },  (err) => { // catch error
          // @todo: We should check for errors ?!?
              reject(err);
            });
      }
      else resolve(this.carts);
    });
    return promise;
  }

  // return from Cart Holder (carts)

  retrieveByUser(tenantId: string, userId: string ) {
      let promise = new Promise((resolve) => {
        resolve (this.carts.filter((cart) => { return (cart.tenantId === tenantId) && (cart.userId === userId); }));
    });
    return promise;
  }

  retrieveByUserAndStore(tenantId: string, storeId: string, userId: string) {
      let promise = new Promise((resolve) => {
        resolve (
          this.carts.filter((cart) => {return (cart.tenantId === tenantId) && (cart.userId === userId) && (cart.storeId === storeId); })
         );
      });
    return promise;
  }
  // {
  //    let promise = new Promise((resolve, reject) => {
  //      this.retrieveAllCarts().then((data: Cart[]) => {
  //  resolve (data.filter((cart) => { return (cart.storeId === storeId) && (cart.userId === userId) && (cart.tenantId === tenantId); }));
  //   },  (err) => { // catch error
  //       // @todo: We should check for errors ?!?
  //           reject(err);
  //         });
  //   });
  //   return promise;
  // }

  addItem(cartId: string, product: CartItem) {
    let payload = product.toJson();
    let promise = new Promise((resolve, reject) => {
        this.apiProvider.api('POST', '/v1/cart/' + cartId, payload)
      .then((response: any) => {
        if (response.id) {
          const cart = Cart.fromJson(response);
          const position = this.carts.findIndex((item) => { return item.id === cart.id; });
          this.carts.splice(position, 1, cart);
          this.cartState(cart);
          resolve(cart);
        } else {
          reject();
        }
      },  (err) => { // catch error
        // @todo: We should check for errors ?!?
            reject(err);
          });
      });

    return promise;
  }

  // TODO add code //404!
  update(tenantId: string, storeId: string, userId: string, cartId: string, tableId?: string) {
    let payload: any = {
      'tenantId': tenantId,
      'storeId': storeId,
      'userId': userId
    };
    
    if(tableId) payload.tableId = tableId;

    let promise = new Promise((resolve, reject) => {
        this.apiProvider.api('PUT', '/v1/cart/' + cartId, payload)
      .then((response: any) => {
        // if (response._id) {
          if (response.id) {
          // this.carts[response._id] = response;
          // this.cartState(response);
          const cart = Cart.fromJson(response);
          const position = this.carts.findIndex((item) => { return item.id === cart.id; });
          if (position > -1) {
            this.carts.splice(position, 1, cart);
          }
          else {
            this.carts.push(cart);
          }
          this.cartState(cart);
          console.log('deleting');
          resolve(cart);
        } else {
          reject();
        }
      },  (err) => { // catch error
        // @todo: We should check for errors ?!?
            reject(err);
          });
      });

    return promise;
  }

  // TODO test
  delete(cartId: string) {
    let payload = {};
    let promise = new Promise((resolve, reject) => {
        this.apiProvider.api('DELETE', '/v1/cart/' + cartId, payload)
      .then((response: any) => {
        // if (response._id) {
          if (response.id) {
          // this.carts[response._id] = response;
          // this.cartState(response);
          const cart = Cart.fromJson(response);
          const position = this.carts.findIndex((item) => { return item.id === cart.id; });
          this.carts.splice(position, 1);
          this.cartsObservable.next(this.carts);
          console.log('deleting');
          resolve(this.carts);
        } else {
          reject();
        }
      },  (err) => { // catch error
        // @todo: We should check for errors ?!?
            reject(err);
          });
      });

    return promise;
  }

  // TODO add code open:closed
  changeStatus(cartId: string) {
    // http://{{url}}/v1/cart/57b2dc1aca661db6009fdf12/status/open
    // PATCH
    // need to retreive status of cart?
    let payload = {};
    let promise = new Promise((resolve, reject) => {
         this.retrieve(cartId).then(
            (result: any) => {
                if (result.id) {
                  let newStatus: string = (this.currentCart.status === 'open' ? 'closed' : 'open');
                  // this.apiProvider.api('PATCH','v1/cart/'+cartId+'/status/'+newStatus, payload);
                  this.apiProvider.api('PATCH', `/v1/cart/${cartId}/status/${newStatus}`, payload).then((response: any) => {
                      if (response.id) {
                        // this.carts[response._id] = response;
                        // this.cartState(response);
                        const cart = Cart.fromJson(response);
                        const position = this.carts.findIndex((item) => { return item.id === cart.id; });
                        this.carts.splice(position, 1, cart);
                        this.cartState(cart);
                        console.log('resoving');
                        resolve(cart); // ??
                      } else {
                        reject();
                      }
                    },  (err) => { // catch error
                      // @todo: We should check for errors ?!?
                          reject(err);
                 });                  // then
                } else {
                  // TODO add error
                  reject();
                }
      },  (err) => { // catch error
        // @todo: We should check for errors ?!?
            reject(err);
          });
      });

    return promise;
  }
  //
  // TODO add code
  paid(cartId: string) {
    // http://{{url}}/v1/cart/57ad9b365179a63b00b717dc/paid
    // POST
     let payload: any = {};
      // payload.storeId = 'typicode';
      let promise = new Promise( (resolve, reject)  => {
      this.apiProvider.api('POST', `/v1/cart/${cartId}/paid`, payload)
      .then((response: any) => {
          // getting 800 error will handle errors when handler is ready
          if (response.id) {
            // this.carts[response._id] = response;
            // this.cartState(response);
            // console.log('resolving');
            // resolve(response);
            const cart = Cart.fromJson(response);
            const position = this.carts.findIndex((item) => { return item.id === cart.id; });
            this.carts.splice(position, 1, cart);
            this.cartState(cart);
            console.log('resolving');
            resolve(cart);
          } else {
            reject('Error cart#1');

          }
        }, (err) => {
            // @todo: We should check for errors ?!?
            reject(err);
          });
        });
    return promise;
  }

  // todo need attention
  retrieveItem(cartId: string, productId: string) {
    // http://{{url}}/v1/cart/57ad9b365179a63b00b717dc/ksjldhflkdsjfhlds
    // GET
    let payload: any = {};
      let promise = new Promise( (resolve, reject)  => {
      this.apiProvider.api('GET', `/v1/cart/${cartId}/${productId}`, payload)
      .then((response: any) => {
          // getting 800 error will handle errors when handler is ready
          if (response.productId) {
            // turn into Product
            resolve(Product.inCartFromJson(response));
          } else {
            reject('Error retrieving carts');

          }
        }, (err) => {
            // @todo: We should check for errors ?!?
            reject(err);
          });
        });
    return promise;
  }

  // cartItem and draw the id?
  updateCartItem(cartId: string, productId: string, updatedProduct: CartItem) {
     // http://{{url}}/v1/cart/57ad9b365179a63b00b717dc/ksjldhflkdsjfhlds
     // PUT
      let payload: any = updatedProduct.toJson();
      let promise = new Promise( (resolve, reject)  => {
      this.apiProvider.api('PUT', `/v1/cart/${cartId}/${productId}`, payload)
      .then((response: any) => {
          // getting 800 error will handle errors when handler is ready
          if (response.id) {
            // this.carts[response._id] = response;
            // this.cartState(response);
            // console.log('resolving');
            // resolve(response);
            const cart = Cart.fromJson(response);
            const position = this.carts.findIndex((item) => { return item.id === cart.id; });
            this.carts.splice(position, 1, cart);
            this.cartState(cart);
            console.log('updating');
            resolve(cart);
          } else {
            reject('Error in updating Cart Item');

          }
        }, (err) => {
            // @todo: We should check for errors ?!?
            reject(err);
          });
        });
    return promise;
  }

  // probably no login on backend
  deleteItem(cartId: string, productId: string) {
     // http://{{url}}/v1/cart/57ad9b365179a63b00b717dc/ksjldhflkdsjfhlds
     // DELETE
     console.log(`deleting from cart ${cartId} the following Item ${productId}`);
     let payload: any = {};
     let promise = new Promise((resolve, reject) => {
        this.apiProvider.api('DELETE', `/v1/cart/${cartId}/${productId}`, payload)
      .then((response: any) => {
        if (response.id) {
          // this.carts[response._id] = response;
          // this.cartState(response);
          // resolve(response);
          const cart = Cart.fromJson(response);
          const position = this.carts.findIndex((item) => { return item.id === cart.id; });
          this.carts.splice(position, 1, cart);
          this.cartState(cart);
          console.log('deleting item');
          resolve(cart); // ??
        } else {
          reject();
        }
      },  (err) => { // catch error
        // @todo: We should check for errors ?!?
            reject(err);
          });
      });

    return promise;

  }

  deleteAllItems(cartId: string){
    console.log(`deleting all items from cart ${cartId} `);
     let payload: any = {};
     let promise = new Promise((resolve, reject) => {
        this.apiProvider.api('DELETE', `/v1/cart/${cartId}/flush`, payload)
      .then((response: any) => {
        if (response.id) {
          // this.carts[response._id] = response;
          // this.cartState(response);
          // resolve(response);
          const cart = Cart.fromJson(response);
          const position = this.carts.findIndex((item) => { return item.id === cart.id; });
          this.carts.splice(position, 1, cart);
          this.cartState(cart);
          console.log('deleting item');
          resolve(cart); // ??
        } else {
          reject();
        }
      },  (err) => { // catch error
        // @todo: We should check for errors ?!?
            reject(err);
          });
      });

    return promise;
  }


  // TODO : GIWRGO EINAI DIKH SOU DOULEIA
  // getDetails (cartId: string) {
  //   let cart: Cart;
  //   if (!this.carts[cartId]) {  // we don't have an active cart stored
  //     // So, let's create a new one and store it in our cache
  //     cart = this.emptyCart();
  //     this.carts[cartId] = cart;
  //   }else {
  //     cart = this.carts[cartId];
  //   }
  //   // @todo: we should ask the APIs to recalculate...
  //   // cart.total = 0;
  //   // angular.forEach(cart.items, function (value, key) {
  //   // cart.total += value.price * value.quantity;
  //   // });
  //   return cart;
  // }

  // setCurrentCart (id: string) {
  //   let cart: Cart = this.getDetails(id);
  //   this.currentCart = Cart.fromJson(this.emptyCart());
  //   for (let item in cart) {
  //     if (cart.hasOwnProperty(item)) {
  //       // this.currentCart[item] = cart[item];
  //       const position = this.currentCart.getCartItems().findIndex((item) => { return item.getProduct().id === cart.id; });
  //       this.carts.splice(position, 1, cart);
  //     }
  //   }
  //   this.cartObservable.next(this.currentCart);
  //   console.log(this.carts);
  // }

  // Deserializers rename to & from

  // TODO FIX
  // deserializeCart(incoming: any) {

  //  let items: CartItem[];
  //  items = [];
  //  for (let item of incoming.items) {
  //       // let tempCartItem =
  //       let tempCartItem = new CartItem(
  //         Product.inCartFromJson(item)
  //         , item.quantity);
  //       items.push(tempCartItem);
  //  }
  //  return new Cart(undefined, undefined, undefined, items, undefined, incoming._id);
  // }

  deserializeCarts(incoming: any) {
    let carts: Cart[] = _.map((_.values(incoming)), Cart.fromJson);
    return carts;
  }
}