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purchase.component.ts

import { Injectable } from "@angular/core";
import { RequestMethod } from "@angular/http";
import { Store } from "@ngrx/store";
import { Observable } from "rxjs/Observable";
import {
    AppState,
    ActionCreator,
    UserModel,
    BackendService,
    LoggerService,
    PurchaseModel,
    GoalModel
} from "../../../shared";

@Injectable()

export class PurchaseService {

    constructor(private store: Store<AppState>, private backendService: BackendService, private log: LoggerService) {

    }

    public saveMonthlyPurchase(goal: GoalModel) {
        return this.purchase(goal.monthlyPayment, "SEPA", 12, goal.id);
    }

    public saveCurrentPurchase() {
        const purchase: PurchaseModel = this.getPurchase();
        const goal : GoalModel = this.getGoal();
        return this.purchase(purchase.amount, "SEPA", 1, goal.id);
    }

    public acceptPolicy() {

        const user: UserModel = this.getUser();

        const data = {
            "userId": user.id,
            "effectiveDate": new Date(),
            "requestDate": new Date()
        };

        return this.backendService.request("/api/v1/policy", data, RequestMethod.Post)
            .map(response => {
                const policyId = response.json().policyId;
                this.log.info("received policyId " + policyId, this);
                user.policyId = policyId;
                this.store.dispatch(ActionCreator.updateUser(user));
            });
    }

    private purchase(amount: Number, paymentType: string, frequency: number, goalId: string) {
        const user: UserModel = this.getUser();

        this.log.info("purchase policy goalId:" + goalId, this);

        const data = {
            "userId": user.id,
            "policyId": user.policyId,
            "goalId": goalId,
            "paymentAgreement": {
                "accountNumber": user.payment.iban,
                "accountName": user.payment.accountName,
                "amount": amount,
                "startDate": new Date(),
                "paymentType": paymentType,
                "currency": "EUR",
                "frequency": frequency,
            }
        };
        this.log.info("Purchase will be saved. " + JSON.stringify(data), this);
        return this.backendService.request("/api/v1/purchase", data, RequestMethod.Post);
    }

    private getUser(): UserModel {

        let user: UserModel;
        this.store.select(state => state.user).subscribe(u => user = u).unsubscribe();
        return user;
    }

    private getPurchase(): PurchaseModel {

        let purchase: PurchaseModel;
        this.store.select(state => state.currentPurchase).subscribe(p => purchase = p).unsubscribe();
        return purchase;
    }

    private getGoal(): GoalModel {

        let goal: GoalModel;
        this.store.select(state => state.currentGoal).subscribe(g => goal = g).unsubscribe();
        return goal;
    }

}