/**
 * 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, OnInit, inject } from '@angular/core';
import { CommonModule } from '@angular/common';
import { FormsModule } from '@angular/forms';
import { MatIconModule } from '@angular/material/icon';
import { ActivatedRoute, Router } from '@angular/router';
import { catchError, of } from 'rxjs';
import { CashierService } from '../../cashier/cashier.service';
import { SettingsService } from 'app/settings/settings.service';
import { STANDALONE_SHARED_IMPORTS } from 'app/standalone-shared.module';

interface Denom {
  id: number;
  value: number;
  kind: 'note' | 'coin';
  label: string;
}

/**
 * Migrate Cash Denomination — the vault-side counterpart to Migrate Opening Balances.
 *
 * A freshly set-up institution's chart of accounts carries a "Cash at Vault" GL balance (defined via
 * Migrate Opening Balances, or not yet defined at all), but that figure is meaningless to a cashier
 * standing at the drawer until it is broken into actual notes and coins, and the branch has nowhere
 * to track that breakdown until its first business day is open. This screen is the one place both of
 * those happen together: count the drawer, and it either defines the cash GL's opening balance from
 * that count (nothing posted to it yet) or checks the count against what is already posted, then
 * opens the business day with that same breakdown - so a new bank goes from "GL seeded" straight to
 * "vault countable" without a separate trip through Manage Tellers or Open Business Day first.
 */
@Component({
  selector: 'mifosx-migrate-cash-denomination',
  templateUrl: './migrate-cash-denomination.component.html',
  styleUrls: ['./migrate-cash-denomination.component.scss'],
  standalone: true,
  imports: [
    CommonModule,
    FormsModule,
    MatIconModule,
    ...STANDALONE_SHARED_IMPORTS
  ]
})
export class MigrateCashDenominationComponent implements OnInit {
  private service = inject(CashierService);
  private settingsService = inject(SettingsService);
  private route = inject(ActivatedRoute);
  private router = inject(Router);

  officeData: any[] = [];
  officeId: number | null = null;
  /** Bound to the datepicker as a Date, converted to a strict yyyy-MM-dd string only when
   *  submitting — the branchday endpoints parse this with LocalDate.parse() directly, with no
   *  locale/dateFormat hint alongside it, so a locale-formatted string (what dateUtils.formatDate
   *  produces) is rejected outright. */
  businessDate: Date = new Date();
  maxDate = new Date();

  glLoading = false;
  glStatus: any = null;
  glError = '';

  notes: Denom[] = [];
  coins: Denom[] = [];
  counts: Record<number, number> = {};

  submitting = false;
  errorMsg = '';
  successMsg = '';
  result: any = null;

  /** Only asked for when the counted total disagrees with an already-posted GL balance — mirrors
   *  the same "explain the gap" gate Open Business Day applies. */
  differenceReason = '';

  get allDenoms(): Denom[] {
    return [
      ...this.notes,
      ...this.coins
    ];
  }

  ngOnInit(): void {
    this.maxDate = this.settingsService.businessDate;
    this.businessDate = this.maxDate;

    this.route.data.subscribe((data: { offices: any }) => {
      this.officeData = data.offices || [];
    });

    this.service.getActiveDenominations().subscribe({
      next: (list) => {
        const rows: Denom[] = (list || []).map((x: any) => ({
          id: x.id,
          value: x.denomination,
          kind: x.kind,
          label: '₹' + x.denomination
        }));
        this.notes = rows.filter((r) => r.kind === 'note').sort((a, b) => b.value - a.value);
        this.coins = rows.filter((r) => r.kind === 'coin').sort((a, b) => b.value - a.value);
      },
      error: () => {
        this.notes = [];
        this.coins = [];
      }
    });
  }

  onOfficeChange(): void {
    this.glStatus = null;
    this.glError = '';
    this.result = null;
    this.successMsg = '';
    this.errorMsg = '';
    if (!this.officeId) return;

    this.glLoading = true;
    this.service
      .cashGlStatus(this.officeId)
      .pipe(catchError(() => of(null)))
      .subscribe((res: any) => {
        this.glLoading = false;
        this.glStatus = res;
        if (res && res.configured === false) {
          this.glError = res.message || 'No cash GL account is configured for this tenant yet.';
        }
      });
  }

  countFor(d: Denom): number {
    return this.counts[d.id] || 0;
  }

  subtotalFor(d: Denom): number {
    return this.countFor(d) * d.value;
  }

  onCountChange(d: Denom, raw: any): void {
    this.counts[d.id] = Math.max(0, Math.floor(Number(raw) || 0));
  }

  bumpCount(d: Denom, delta: number): void {
    this.counts[d.id] = Math.max(0, (this.counts[d.id] || 0) + delta);
  }

  get countedTotal(): number {
    return this.allDenoms.reduce((s, d) => s + this.subtotalFor(d), 0);
  }

  /** Whether this office's GL already carries a balance the count has to match, vs. an empty
   *  account the count itself will define. */
  get glHasBalance(): boolean {
    return !!this.glStatus?.hasBalance;
  }

  get glTarget(): number {
    return Number(this.glStatus?.currentBalance ?? 0);
  }

  get isReconciled(): boolean {
    if (!this.glStatus || this.glStatus.configured === false) return false;
    if (this.countedTotal <= 0) return false;
    return !this.glHasBalance || this.countedTotal === this.glTarget;
  }

  get needsDifferenceReason(): boolean {
    return (
      this.glHasBalance && this.countedTotal > 0 && this.countedTotal !== this.glTarget && !this.differenceReason.trim()
    );
  }

  get canSubmit(): boolean {
    return (
      !!this.officeId &&
      !!this.businessDate &&
      !this.glError &&
      this.countedTotal > 0 &&
      !this.needsDifferenceReason &&
      !this.submitting
    );
  }

  private denominationPayload() {
    return this.allDenoms
      .filter((d) => this.countFor(d) > 0)
      .map((d) => ({ denominationId: d.id, denominationValue: d.value, count: this.countFor(d) }));
  }

  /** Strict yyyy-MM-dd, independent of the viewer's locale/date-format setting — see the comment on
   *  `businessDate` for why this can't go through dateUtils.formatDate(). */
  private toIsoDate(d: Date): string {
    const pad = (n: number) => String(n).padStart(2, '0');
    return `${d.getFullYear()}-${pad(d.getMonth() + 1)}-${pad(d.getDate())}`;
  }

  submit(): void {
    if (!this.canSubmit || !this.officeId) return;
    this.submitting = true;
    this.errorMsg = '';
    this.successMsg = '';
    this.service
      .migrateCashDenomination(
        this.officeId,
        this.toIsoDate(this.businessDate),
        this.denominationPayload(),
        this.differenceReason.trim() || undefined
      )
      .pipe(
        catchError((err: any) => {
          this.errorMsg =
            err?.error?.errors?.[0]?.defaultUserMessage ??
            err?.error?.message ??
            'Could not migrate cash denomination.';
          return of(null);
        })
      )
      .subscribe((res: any) => {
        this.submitting = false;
        if (res) {
          this.result = res;
          this.successMsg = res.glOpeningBalancePosted
            ? `Cash GL opening balance defined at ₹${this.countedTotal.toLocaleString('en-IN')} and business day ${res.businessDate} opened.`
            : `Business day ${res.businessDate} opened — count matched the existing GL balance.`;
        }
      });
  }

  goToBranchDay(): void {
    this.router.navigate(['/branch-ops/day-register']);
  }
}