import { Injectable } from '@angular/core';
import { Subject, BehaviorSubject, Observable }  from 'rxjs';
import { HttpClient, HttpParams } from '@angular/common/http';
import { Order } from './order.model';
import { UserService } from '../user.service';
import { User } from '../user.model';
import { LineItem} from '../items/lineitem.model';

@Injectable({providedIn: 'root'})

export class OrderService {
	private dataStore: { user: User, order: Order } = {
		user:{
			address: '',
			session: '',
			blocktime: 0
		},
		order: {
			address: '',
			session: '',
			timestamp: '',
			closed: false,
			lines: [
				{
					qty: 1,
					name: '',
					cost:0
				}
			]
		}
	};
	private _orderUpdated: BehaviorSubject<Order> = new BehaviorSubject(this.dataStore.order);
	public readonly orderUpdate: Observable<Order> = this._orderUpdated.asObservable();
	public userUpdate: Observable<User>;

	constructor(
		private http: HttpClient,
		public userService: UserService
	) {
		this.userUpdate = userService.userUpdate;
		this.userUpdate.subscribe((user) => {
			this.dataStore.user = user;
			//console.log('OS: const', user);
			this.getOrder(this.dataStore.user.session);
		});
	}

	getOrder(session: string) {
		const params = new HttpParams().append('session', session);
		let obs = this.http.get<{message: string, order: any}>('http://localhost:3000/api/order', { headers:{}, params:params, observe: 'response'});

		obs.subscribe((OrderDataResponse) => {
			if (OrderDataResponse.status == 200) {
				this.dataStore.order = OrderDataResponse.body!.order;
				this._orderUpdated.next(Object.assign({}, this.dataStore).order);
			} else {
				console.log('No order found');
			}
		});

		return obs;
	}

	addToOrder(lineItem: LineItem) {
		if (this.dataStore.order.address.length == 0) {
			console.log('No open order, creating...', lineItem);
			this.createOrder();
		} else {
			console.log('Open order, adding...', lineItem);
		}
	}

	createOrder() {
		var order:Order = {
			address: this.dataStore.user.address,
			session: this.dataStore.user.session,
			closed: false,
			lines: []
		};
		let obs = this.http.post<{message: string}>('http://localhost:3000/api/order', {order: order});

		obs.subscribe((orderData) => {
			console.log('Create order', orderData);
			this.getOrder(this.dataStore.user.session);
		});

		return obs;

	}

}