/**
 * 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 { RouterModule } from '@angular/router';
import { MatIconModule } from '@angular/material/icon';
import { MatSnackBar, MatSnackBarModule } from '@angular/material/snack-bar';
import { MatFormFieldModule } from '@angular/material/form-field';
import { MatSelectModule } from '@angular/material/select';
import { MatInputModule } from '@angular/material/input';
import { catchError } from 'rxjs/operators';
import { of } from 'rxjs';
import { CashierService } from '../cashier.service';

type PageState = 'idle' | 'searching' | 'loaded' | 'submitting' | 'success';

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

interface ShareCharge {
  id: number;
  name: string;
  amount: number;
  currencySymbol: string;
}

@Component({
  selector: 'mifosx-share-collection',
  templateUrl: './share-collection.component.html',
  styleUrls: [
    '../cashier-shared.scss',
    './share-collection.component.scss'
  ],
  standalone: true,
  imports: [
    CommonModule,
    FormsModule,
    RouterModule,
    MatIconModule,
    MatSnackBarModule,
    MatFormFieldModule,
    MatSelectModule,
    MatInputModule
  ]
})
export class ShareCollectionComponent implements OnInit {
  private service = inject(CashierService);
  private snackBar = inject(MatSnackBar);

  pageState: PageState = 'idle';
  accountInput = '';
  transactionDate = '';
  paymentTypeId: number | null = null;
  paymentTypes: any[] = [];
  note = '';
  errorMsg = '';
  saving = false;

  account: any = null;
  charges: ShareCharge[] = [];
  collectionResult: any = null; // filled after successful POST

  // Editable fields — cashier can override if API returns 0
  requestedSharesInput = 0;
  pricePerShare = 0;

  // ── Denomination ────────────────────────────────────────────────────────────
  notes: Denomination[] = [];
  coins: Denomination[] = [];
  denominationCounts: Record<string, number> = {};

  get shareAmount(): number {
    return this.requestedSharesInput * this.pricePerShare;
  }

  get totalChargeAmount(): number {
    return this.charges.reduce((s, c) => s + c.amount, 0);
  }

  get totalAmount(): number {
    return this.shareAmount + this.totalChargeAmount;
  }

  get currencySymbol(): string {
    return this.account?.currency?.displaySymbol ?? '₹';
  }

  get isCashPayment(): boolean {
    if (this.paymentTypeId === null) return true;
    const pt = this.paymentTypes.find((p: any) => p.id === this.paymentTypeId);
    return !!pt?.isCashPayment;
  }

  get allDenominations(): Denomination[] {
    const desc = (a: Denomination, b: Denomination) => b.value - a.value;
    return [
      ...[...this.notes].sort(desc),
      ...[...this.coins].sort(desc)
    ];
  }

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

  get denomMatchesTotal(): boolean {
    return this.denominationTotal === this.totalAmount;
  }

  get isValid(): boolean {
    if (!this.account || this.totalAmount <= 0 || !this.transactionDate) return false;
    if (this.isCashPayment && this.allDenominations.length > 0) {
      return this.denomMatchesTotal;
    }
    return true;
  }

  ngOnInit(): void {
    const d = new Date();
    this.transactionDate = `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}-${String(d.getDate()).padStart(2, '0')}`;
    this.service
      .getPaymentTypes()
      .pipe(catchError(() => of([])))
      .subscribe((types: any[]) => (this.paymentTypes = types || []));
    this.loadDenominations();
  }

  private loadDenominations(): void {
    this.service
      .getActiveDenominations()
      .pipe(catchError(() => of([])))
      .subscribe((list: any[]) => {
        const rows: Denomination[] = (list || []).map((d: any) => ({
          id: d.id,
          value: d.denomination ?? d.value,
          kind: d.type === 'coin' ? 'coin' : 'note',
          label: '₹' + (d.denomination ?? d.value)
        }));
        const order = (a: Denomination, b: Denomination) => b.value - a.value;
        this.notes = rows.filter((r) => r.kind === 'note').sort(order);
        this.coins = rows.filter((r) => r.kind === 'coin').sort(order);
      });
  }

  // ── Denomination helpers ──────────────────────────────────────────────────

  denomKey(d: Denomination): string {
    return `${d.kind}:${d.value}`;
  }

  countFor(d: Denomination): number {
    return this.denominationCounts[this.denomKey(d)] || 0;
  }

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

  onDenomChange(d: Denomination, raw: any): void {
    this.denominationCounts[this.denomKey(d)] = Math.max(0, Math.floor(Number(raw) || 0));
  }

  bumpDenom(d: Denomination, delta: number): void {
    this.denominationCounts[this.denomKey(d)] = Math.max(0, this.countFor(d) + delta);
  }

  clearDenominations(): void {
    this.denominationCounts = {};
  }

  searchAccount(): void {
    const query = this.accountInput.trim();
    if (!query) return;
    this.pageState = 'searching';
    this.account = null;
    this.charges = [];
    this.errorMsg = '';

    this.service
      .getShareAccountForCollection(query)
      .pipe(
        catchError((err) => {
          this.errorMsg =
            err?.error?.errors?.[0]?.defaultUserMessage ||
            err?.error?.developerMessage ||
            'Account not found. Please check the account ID and try again.';
          this.pageState = 'idle';
          return of(null);
        })
      )
      .subscribe((acc: any) => {
        if (!acc) return;
        this.account = acc;

        // Auto-detect shares from summary or first pending purchasedShares entry
        const pendingTx = (acc.purchasedShares || []).find(
          (t: any) =>
            t.status?.code === 'purchasedSharesStatusType.applied' && t.type?.code === 'purchasedSharesType.purchased'
        );
        this.requestedSharesInput = Number(
          acc.summary?.totalPendingForApprovalShares || pendingTx?.numberOfShares || acc.requestedShares || 0
        );
        this.pricePerShare = Number(pendingTx?.purchasedPrice || acc.currentMarketPrice || acc.unitPrice || 0);

        // Show ALL charges on the account — no type filtering
        this.charges = (acc.charges || []).map((c: any) => ({
          id: c.chargeId ?? c.id,
          name: c.name,
          amount: Number(c.amount ?? c.amountOutstanding ?? 0),
          currencySymbol: c.currency?.displaySymbol ?? '₹'
        }));

        this.pageState = 'loaded';
      });
  }

  recalc(): void {
    // triggered by input changes — nothing extra needed, getters auto-recalculate
  }

  submit(): void {
    if (!this.isValid || this.saving) return;
    this.saving = true;
    const payload = {
      shareAccountId: this.account.id,
      accountNo: this.account.accountNo,
      clientName: this.account.clientName,
      transactionDate: this.transactionDate,
      requestedShares: this.requestedSharesInput,
      pricePerShare: this.pricePerShare,
      shareAmount: this.shareAmount,
      chargeAmount: this.totalChargeAmount,
      totalAmount: this.totalAmount,
      paymentTypeId: this.paymentTypeId || null,
      note: this.note || null
    };

    this.service.collectSharePayment(payload).subscribe({
      next: (result: any) => {
        this.collectionResult = result;
        this.snackBar.open('Share collection posted successfully.', 'Close', { duration: 3000 });
        this.pageState = 'success';
        this.saving = false;
      },
      error: (err: any) => {
        const msg =
          err?.error?.errors?.[0]?.defaultUserMessage ||
          err?.error?.developerMessage ||
          err?.error?.defaultUserMessage ||
          'Collection failed. Please try again.';
        this.snackBar.open(msg, 'Close', { duration: 8000 });
        this.saving = false;
      }
    });
  }

  reset(): void {
    this.pageState = 'idle';
    this.accountInput = '';
    this.account = null;
    this.charges = [];
    this.errorMsg = '';
    this.note = '';
    this.paymentTypeId = null;
    this.requestedSharesInput = 0;
    this.pricePerShare = 0;
    this.collectionResult = null;
    this.saving = false;
    this.clearDenominations();
  }
}