import * as _ from 'lodash';

import { Product } from '../product/product';

export interface ExportMe {

}

export class CartItem {
  public cost: number;
  // public courseId: string;

  public static fromJson (obj: any) {
    return new CartItem(
                Product.inCartFromJson(obj),
                obj.quantity, 
                obj.courseId ? obj.courseId: null,
                obj.size ? obj.size: null,
                obj.colour ? obj.colour: null,
                Product.inCartFromJson(obj).getPrinter()
                );
  }

  public toJson() {
    let cartItem: any = this.product.toJson();
    cartItem.quantity = this.getQuantity();
    if(this.courseId) cartItem.courseId = this.courseId;
    if(this.printer)  cartItem.printer  = this.printer;
    return cartItem;
  }

  // public printer_toJson(){
  //   let printerJson: any = {
  //     belonging: this.printer["belonging"],
  //     status: this.printer["status"]
  //   }
  //   return printerJson;
  // }

  // public printer_fromJson(obj: any){
  // if ( obj ){
  //   return JSON.parse(obj);
  // }
  // else
  //   return null;
  // }
  constructor( // TODO have a unique itemId for each CartItem
      public product: Product
      , public quantity: number
      , public courseId?: string
      , public size?: string
      , public colour?: string
      , public printer?: object
    ) {
    this.cost = this.product.getPrice() * this.quantity;
  }

  updateItemQuantity(updatedQuantity: number) {
    this.quantity = updatedQuantity;
    this.cost = this.product.getPrice() * this.quantity;
  }

  getCost()     { return this.cost;     }

  getProduct()  { return this.product;  }

  getQuantity() { return this.quantity; }

  getSize()     { return this.size;     }

  getColour()   { return this.colour;   }

  getCourseId() { return this.courseId? this.courseId: null; }

  getPrinter() { return this.printer? this.printer: null; }
}

export class Cart {

  public cartCost: number = 0;
  private numItems: number;

  public static fromJson (obj: any) {
    const items = _.chain(obj.items).values().map(CartItem.fromJson).value();
    return new Cart(Number(obj.numItems), obj.storeId, obj.tenantId, obj.userId, items, obj.status, obj.id, obj.tableId, obj.created, obj.__v, obj._rev);
  }

  public toJson() {
    const cartJson: any = {
        __v: this.__v ? this.__v :  '',
        userId: this.userId,
        tenantId: this.tenantId,
        id: this.id,
        created: this.created ? this.created : '',
        items: [] , // carItems to json
        numItems: this.getItemsCount(),
        total: this.getCartCost(),
        storeId: this.storeId,
        status: this.status,
        tableId: this.tableId
    };
    if(this._rev) cartJson._rev = this._rev;
    return cartJson;
  }

  constructor(
       numItems: number
      , public storeId?: string // TODO should be a Store instance when we have that
      , public tenantId?: string
      , public userId?: string
      , public cartItems?: CartItem[]
      , public status?: string
      , public id?: string
      , public tableId?: string
      , public created?: string
      , public __v?: string
      , public _rev?: string
    ) {
        this.numItems = (_.isUndefined(numItems) || numItems == null? 0 : numItems );
        this.calculateCartCost();
        if (this.id === undefined) { this.id = ''; }
  }

  public calculateCartCost() {
    this.cartCost = 0;
    this.cartItems.forEach( (cItem: CartItem) => {
      this.cartCost += cItem.getCost();
    });
  }

  private findItemInCartItems(keyItem: CartItem) {
    return _.find(this.cartItems, (cItem: CartItem) => {
      return cItem.getProduct().getId() === keyItem.getProduct().getId();
    });
  }

  private findProductInCartItems(keyId: string) {
    return _.find(this.cartItems, (cItem: CartItem) => {
      return cItem.getProduct().getId() === keyId;
    });
  }

  addCartItem(newItem: CartItem) {
    let foundItem: CartItem = this.findItemInCartItems(newItem);

    const position = this.cartItems.findIndex((item) => { return item.getProduct().getId() === newItem.getProduct().getId(); });

    this.numItems+= newItem.getQuantity();
    if (foundItem) {
      //foundItem.updateItemQuantity(foundItem.getQuantity() + newItem.getQuantity());
      this.cartItems[position].updateItemQuantity(foundItem.getQuantity() + newItem.getQuantity());
    }else {
      this.cartItems.push(newItem);
    }
    this.calculateCartCost();
  }

  removeCartItem(idOfProductToRemove: string) {
    let indexOfItemToRemove = _.findIndex(this.cartItems, (cItem: CartItem) => {
      return cItem.getProduct().getId() === idOfProductToRemove;
    });

    if (indexOfItemToRemove === -1) { // Case of failure
      console.error('Failed to remove product with id "'
        + idOfProductToRemove + '". Product was not found in cartItems[].');
    }else {                            // Case of proceeding as normal
      this.numItems -= this.cartItems[indexOfItemToRemove].getQuantity();
      this.cartItems.splice(indexOfItemToRemove, 1);
      this.calculateCartCost();
    }
  }

  getItem(prodId: string) {
    const indexOfItem = _.findIndex(this.cartItems, (cItem: CartItem) => {
      return cItem.getProduct().getId() === prodId;
    });
    return this.cartItems[indexOfItem];
  }

  incrementQuantity(prodId: string) {
    let foundItem: CartItem = this.findProductInCartItems(prodId);
    foundItem.updateItemQuantity(foundItem.getQuantity() + 1);
    this.setItemsCount();
    this.calculateCartCost();
    return foundItem;
  }

  decrementQuantity(prodId: string) {
    let foundItem: CartItem = this.findProductInCartItems(prodId);
    foundItem.updateItemQuantity(foundItem.getQuantity() - 1);
    this.setItemsCount();
    this.calculateCartCost();
    return foundItem;
  }


  // getItemsCount() { return this.cartItems.length; }

  setItemsCount() { this.numItems = this.getCartItems().map(a => a.getQuantity()).reduce((a,b) => a+b, 0); }

  getItemsCount() { return this.numItems;         }
  getStoreId()    { return this.storeId;          }
  getStatus()     { return this.status;           }
  getCartItems()  { return this.cartItems;        }
  getCartCost()   { return this.cartCost;         }
  getTableId()    { return this.tableId;          }


}