/**
 * Billing View Model
 *
 * View model for sponsor billing data with UI-specific transformations.
 * Transforms BillingViewData into UI-ready state with formatting and derived fields.
 */
import type { BillingViewData } from '@/lib/view-data/BillingViewData';
import { ViewModel } from "../contracts/view-models/ViewModel";
import { CurrencyDisplay } from "../display-objects/CurrencyDisplay";
import { DateDisplay } from "../display-objects/DateDisplay";

/**
 * BillingViewModel
 *
 * View Model for sponsor billing data.
 * Transforms BillingViewData into UI-ready state with formatting and derived fields.
 */
export class BillingViewModel extends ViewModel {
  paymentMethods: PaymentMethodViewModel[];
  invoices: InvoiceViewModel[];
  stats: BillingStatsViewModel;

  constructor(viewData: BillingViewData) {
    super();
    this.paymentMethods = viewData.paymentMethods.map(pm => new PaymentMethodViewModel(pm));
    this.invoices = viewData.invoices.map(inv => new InvoiceViewModel(inv));
    this.stats = new BillingStatsViewModel(viewData.stats);
  }
}

/**
 * PaymentMethodViewModel
 *
 * View Model for payment method data.
 * Provides formatted display labels and expiry information.
 */
export class PaymentMethodViewModel extends ViewModel {
  id: string;
  type: 'card' | 'bank' | 'sepa';
  last4: string;
  brand?: string;
  isDefault: boolean;
  expiryMonth?: number;
  expiryYear?: number;
  bankName?: string;

  // UI-specific derived fields (primitive outputs only)
  readonly displayLabel: string;
  readonly expiryDisplay: string | null;

  constructor(viewData: {
    id: string;
    type: 'card' | 'bank' | 'sepa';
    last4: string;
    brand?: string;
    isDefault: boolean;
    expiryMonth?: number;
    expiryYear?: number;
    bankName?: string;
    displayLabel: string;
    expiryDisplay: string | null;
  }) {
    super();
    this.id = viewData.id;
    this.type = viewData.type;
    this.last4 = viewData.last4;
    this.brand = viewData.brand;
    this.isDefault = viewData.isDefault;
    this.expiryMonth = viewData.expiryMonth;
    this.expiryYear = viewData.expiryYear;
    this.bankName = viewData.bankName;
    this.displayLabel = viewData.displayLabel;
    this.expiryDisplay = viewData.expiryDisplay;
  }
}

/**
 * InvoiceViewModel
 *
 * View Model for invoice data.
 * Provides formatted amounts, dates, and derived status flags.
 */
export class InvoiceViewModel extends ViewModel {
  id: string;
  invoiceNumber: string;
  date: Date;
  dueDate: Date;
  amount: number;
  vatAmount: number;
  totalAmount: number;
  status: 'paid' | 'pending' | 'overdue' | 'failed';
  description: string;
  sponsorshipType: 'league' | 'team' | 'driver' | 'race' | 'platform';
  pdfUrl: string;

  // UI-specific derived fields (primitive outputs only)
  readonly formattedTotalAmount: string;
  readonly formattedVatAmount: string;
  readonly formattedDate: string;
  readonly isOverdue: boolean;

  constructor(viewData: {
    id: string;
    invoiceNumber: string;
    date: string;
    dueDate: string;
    amount: number;
    vatAmount: number;
    totalAmount: number;
    status: 'paid' | 'pending' | 'overdue' | 'failed';
    description: string;
    sponsorshipType: 'league' | 'team' | 'driver' | 'race' | 'platform';
    pdfUrl: string;
    formattedTotalAmount: string;
    formattedVatAmount: string;
    formattedDate: string;
    isOverdue: boolean;
  }) {
    super();
    this.id = viewData.id;
    this.invoiceNumber = viewData.invoiceNumber;
    this.date = new Date(viewData.date);
    this.dueDate = new Date(viewData.dueDate);
    this.amount = viewData.amount;
    this.vatAmount = viewData.vatAmount;
    this.totalAmount = viewData.totalAmount;
    this.status = viewData.status;
    this.description = viewData.description;
    this.sponsorshipType = viewData.sponsorshipType;
    this.pdfUrl = viewData.pdfUrl;
    this.formattedTotalAmount = viewData.formattedTotalAmount;
    this.formattedVatAmount = viewData.formattedVatAmount;
    this.formattedDate = viewData.formattedDate;
    this.isOverdue = viewData.isOverdue;
  }
}

/**
 * BillingStatsViewModel
 *
 * View Model for billing statistics.
 * Provides formatted monetary fields and derived metrics.
 */
export class BillingStatsViewModel extends ViewModel {
  totalSpent: number;
  pendingAmount: number;
  nextPaymentDate: Date;
  nextPaymentAmount: number;
  activeSponsorships: number;
  averageMonthlySpend: number;

  // UI-specific derived fields (primitive outputs only)
  readonly formattedTotalSpent: string;
  readonly formattedPendingAmount: string;
  readonly formattedNextPaymentAmount: string;
  readonly formattedAverageMonthlySpend: string;
  readonly formattedNextPaymentDate: string;

  constructor(viewData: {
    totalSpent: number;
    pendingAmount: number;
    nextPaymentDate: string;
    nextPaymentAmount: number;
    activeSponsorships: number;
    averageMonthlySpend: number;
    formattedTotalSpent: string;
    formattedPendingAmount: string;
    formattedNextPaymentAmount: string;
    formattedAverageMonthlySpend: string;
    formattedNextPaymentDate: string;
  }) {
    super();
    this.totalSpent = viewData.totalSpent;
    this.pendingAmount = viewData.pendingAmount;
    this.nextPaymentDate = new Date(viewData.nextPaymentDate);
    this.nextPaymentAmount = viewData.nextPaymentAmount;
    this.activeSponsorships = viewData.activeSponsorships;
    this.averageMonthlySpend = viewData.averageMonthlySpend;
    this.formattedTotalSpent = viewData.formattedTotalSpent;
    this.formattedPendingAmount = viewData.formattedPendingAmount;
    this.formattedNextPaymentAmount = viewData.formattedNextPaymentAmount;
    this.formattedAverageMonthlySpend = viewData.formattedAverageMonthlySpend;
    this.formattedNextPaymentDate = viewData.formattedNextPaymentDate;
  }
}