/**
 * Copyright since 2025 Mifos Initiative
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

import { Component, inject } from '@angular/core';
import { CommonModule } from '@angular/common';
import { FormsModule } from '@angular/forms';
import { ActivatedRoute, Router } from '@angular/router';
import { MatIconModule } from '@angular/material/icon';
import { catchError, of } from 'rxjs';
import { CashierService } from '../cashier.service';

/** One side of a voucher: a debit or a credit against a single account. */
interface VoucherLine {
  lineNo: number;
  entryType: 'DR' | 'CR';
  glAccountId: number | null;
  savingsAccountId: number | null;
  loanAccountId: number | null;
  partyName: string | null;
  accountNo: string | null;
  amount: number;
  description: string | null;
}

interface Voucher {
  voucherNo: string;
  voucherType: string | null;
  referenceType: string | null;
  referenceId: number | null;
  amount: number | null;
  branchOfficeId: number | null;
  branchName: string | null;
  createdBy: string | null;
  createdAt: string | null;
  verificationStatus: string | null;
  lines: VoucherLine[];
  totalDebit: number;
  totalCredit: number;
  balanced: boolean;
}

/**
 * One voucher, as a slip: which accounts were debited, which credited, and for how much.
 *
 * Looked up by voucher number rather than listed, because that is how a voucher is reached — from a
 * paper slip in someone's hand, or from a number quoted on a statement.
 */
@Component({
  selector: 'mifosx-voucher-view',
  templateUrl: './voucher-view.component.html',
  styleUrls: [
    '../cashier-shared.scss',
    './voucher-view.component.scss'
  ],
  standalone: true,
  imports: [
    CommonModule,
    FormsModule,
    MatIconModule
  ]
})
export class VoucherViewComponent {
  private service = inject(CashierService);
  private route = inject(ActivatedRoute);
  private router = inject(Router);

  voucherNo = '';
  voucher: Voucher | null = null;
  loading = false;
  /** Shown in place of the slip — a bad number and a server error read differently to the user. */
  error: string | null = null;

  constructor() {
    // A voucher number in the URL means someone arrived from a link or a statement rather than by
    // typing, so the slip is fetched straight away instead of showing them an empty search box.
    const fromUrl = this.route.snapshot.queryParamMap.get('voucherNo');
    if (fromUrl) {
      this.voucherNo = fromUrl;
      this.search();
    }
  }

  search(): void {
    const trimmed = (this.voucherNo || '').trim();
    if (!trimmed) {
      this.error = 'Enter a voucher number.';
      this.voucher = null;
      return;
    }

    this.loading = true;
    this.error = null;

    // Kept in the URL so the slip can be linked to and survives a refresh.
    this.router.navigate([], {
      relativeTo: this.route,
      queryParams: { voucherNo: trimmed },
      replaceUrl: true
    });

    this.service
      .voucherDetail(trimmed)
      .pipe(
        catchError((err: any) => {
          this.error =
            err?.error?.errors?.[0]?.defaultUserMessage ??
            err?.error?.developerMessage ??
            `Voucher ${trimmed} could not be loaded.`;
          return of(null);
        })
      )
      .subscribe((res: Voucher | null) => {
        this.loading = false;
        this.voucher = res;
      });
  }

  /** Debits first, then credits — the order a slip is read in. */
  get debitLines(): VoucherLine[] {
    return (this.voucher?.lines ?? []).filter((l) => l.entryType === 'DR');
  }

  get creditLines(): VoucherLine[] {
    return (this.voucher?.lines ?? []).filter((l) => l.entryType === 'CR');
  }

  /**
   * A voucher raised before its sides were recorded. The voucher is real and its number valid — only
   * the posting behind it was never captured — so this reads as an older record, not a broken one.
   */
  get hasNoLines(): boolean {
    return !!this.voucher && this.voucher.lines.length === 0;
  }

  print(): void {
    window.print();
  }
}