/**
 * 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 { MatFormFieldModule } from '@angular/material/form-field';
import { MatSelectModule } from '@angular/material/select';
import { MatInputModule } from '@angular/material/input';
import { forkJoin, of } from 'rxjs';
import { catchError } from 'rxjs/operators';
import { CashierService } from '../cashier.service';
import { AuthenticationService } from '../../core/authentication/authentication.service';

interface DenomRow {
  denominationId: number;
  denominationValue: number;
  kind: string;
  morningCount: number;
  count: number;
  amount: number;
}
interface CashierPos {
  cashierId: number;
  cashierName?: string;
  asOfDate: string;
  totalAmount: number;
  morningTotal: number;
  denominations: DenomRow[];
}

/** Denomination-wise net cash position per cashier as of a given date. */
@Component({
  selector: 'mifosx-cashier-position',
  templateUrl: './cashier-position.component.html',
  styleUrls: [
    '../cashier-shared.scss',
    './cashier-position.component.scss'
  ],
  standalone: true,
  imports: [
    CommonModule,
    FormsModule,
    MatIconModule,
    MatFormFieldModule,
    MatSelectModule,
    MatInputModule
  ]
})
export class CashierPositionComponent implements OnInit {
  private service = inject(CashierService);
  private authService = inject(AuthenticationService);

  tellers: { id: number; name: string }[] = [];
  cashiers: { id: number; label: string }[] = [];
  selectedTellerId: number | null = null;
  selectedCashierId: number | null = null;
  asOfDate = '';
  loading = false;

  results: CashierPos[] = [];
  errorMsg = '';

  // True when logged-in user is a regular cashier — hides teller/cashier filters
  isCashierMode = false;

  ngOnInit(): void {
    const d = new Date();
    this.asOfDate = `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}-${String(d.getDate()).padStart(2, '0')}`;

    this.isCashierMode = this.authService.isCashierUser();

    if (this.isCashierMode) {
      // Auto-load current cashier's own position immediately
      this.loadMe();
    } else {
      this.service
        .getTellers()
        .pipe(catchError(() => of([] as any[])))
        .subscribe((list) => {
          this.tellers = (list || []).map((t: any) => ({ id: t.id, name: t.name }));
          if (this.tellers.length === 1) {
            this.onTellerSelect(this.tellers[0].id);
          }
        });
    }
  }

  /** Load position for the currently authenticated cashier via /me endpoint. */
  loadMe(): void {
    this.loading = true;
    this.results = [];
    this.errorMsg = '';
    forkJoin({
      position: this.service.getCashierPositionForMe(this.asOfDate).pipe(catchError(() => of(null))),
      morning: this.service.getCashierMorningBalance(0, this.asOfDate).pipe(catchError(() => of(null)))
    }).subscribe(({ position, morning }) => {
      this.loading = false;
      if (!position || !position.cashierId) {
        this.errorMsg = 'No cashier record linked to your account. Contact your administrator.';
        return;
      }
      // Reload morning balance using the resolved cashier ID
      this.service
        .getCashierMorningBalance(position.cashierId, this.asOfDate)
        .pipe(catchError(() => of(null)))
        .subscribe((morningData: any) => {
          const morningMap = new Map<number, number>();
          ((morningData?.denominations || []) as any[]).forEach((d: any) =>
            morningMap.set(d.denominationId, d.morningCount ?? 0)
          );
          const morningTotal = Number(morningData?.totalMorning ?? 0);
          this.results = [
            {
              ...position,
              morningTotal,
              denominations: ((position.denominations || []) as any[]).map((d: any) => ({
                ...d,
                morningCount: morningMap.get(d.denominationId) ?? 0
              }))
            }
          ];
        });
    });
  }

  onTellerSelect(tellerId: number): void {
    this.selectedTellerId = tellerId;
    this.selectedCashierId = null;
    this.cashiers = [];
    if (!tellerId) return;
    this.service
      .getCashiersForTeller(tellerId)
      .pipe(catchError(() => of({ cashiers: [] })))
      .subscribe((r: any) => {
        this.cashiers = (r?.cashiers || []).map((c: any) => ({ id: c.id, label: c.staffName }));
        if (this.cashiers.length === 1) {
          this.selectedCashierId = this.cashiers[0].id;
        }
      });
  }

  load(): void {
    this.loading = true;
    this.results = [];
    this.errorMsg = '';

    if (this.selectedCashierId) {
      forkJoin({
        position: this.service
          .cashierPositionReport(this.selectedCashierId, this.asOfDate)
          .pipe(catchError(() => of(null))),
        morning: this.service
          .getCashierMorningBalance(this.selectedCashierId, this.asOfDate)
          .pipe(catchError(() => of(null)))
      }).subscribe(({ position, morning }) => {
        this.loading = false;
        if (!position) {
          this.errorMsg = 'Failed to load position data.';
          return;
        }
        const morningMap = new Map<number, number>();
        ((morning?.denominations || []) as any[]).forEach((d: any) =>
          morningMap.set(d.denominationId, d.morningCount ?? 0)
        );
        const morningTotal = Number(morning?.totalMorning ?? 0);
        const arr: any[] = Array.isArray(position) ? position : [position];
        this.results = arr.map((p: any) => ({
          ...p,
          morningTotal,
          denominations: ((p.denominations || []) as any[]).map((d: any) => ({
            ...d,
            morningCount: morningMap.get(d.denominationId) ?? 0
          }))
        }));
      });
    } else {
      this.service
        .cashierPositionReport(undefined, this.asOfDate)
        .pipe(catchError(() => of(null)))
        .subscribe((data: any) => {
          this.loading = false;
          if (!data) {
            this.errorMsg = 'Failed to load position data.';
            return;
          }
          const arr: any[] = Array.isArray(data) ? data : [data];
          this.results = arr.map((p: any) => ({
            ...p,
            morningTotal: 0,
            denominations: ((p.denominations || []) as any[]).map((d: any) => ({ ...d, morningCount: 0 }))
          }));
        });
    }
  }

  labelForCashier(id: number): string {
    const c = this.cashiers.find((x) => x.id === id);
    return c ? c.label : `Cashier #${id}`;
  }

  notes(pos: CashierPos): DenomRow[] {
    return pos.denominations.filter((d) => d.kind !== 'coin');
  }

  coins(pos: CashierPos): DenomRow[] {
    return pos.denominations.filter((d) => d.kind === 'coin');
  }
}