/**
 * 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 { MatDialog, MatDialogModule } from '@angular/material/dialog';
import { catchError, finalize, of } from 'rxjs';
import { CashierService } from '../cashier.service';
import { VoucherDetailDialogComponent } from './voucher-detail-dialog.component';

/** What the signed-in user's part in a voucher was. */
export type MyRole = 'RAISED' | 'VERIFIED' | 'RAISED_AND_VERIFIED';

/** Which register the voucher was numbered in: receipt, payment, or journal. */
export type VoucherSide = 'CR' | 'DR' | 'JV';

interface MyWorkRow {
  voucherNo: string;
  side: VoucherSide | null;
  voucherType: string | null;
  amount: number | null;
  createdAt: string | null;
  raisedBy: string | null;
  branchName: string | null;
  verificationStatus: string | null;
  verifiedByName: string | null;
  verifiedAt: string | null;
  debitParty: string | null;
  debitAccount: string | null;
  creditParty: string | null;
  creditAccount: string | null;
  /** Sides beyond the one debit and one credit shown — a deposit that also took a charge. */
  extraLines: number;
  myRole: MyRole;
}

interface MyWorkReport {
  from: string;
  to: string;
  username: string;
  displayName: string;
  vouchers: MyWorkRow[];
  count: number;
  raisedCount: number;
  verifiedCount: number;
  receivedTotal: number;
  paymentTotal: number;
  journalTotal: number;
}

/**
 * One person's day at the branch: what they entered and what they approved, in one list.
 *
 * The Received and Payment registers answer "what moved today" across everyone. This answers the
 * question each member of staff asks at a close — "what did I do today" — which those two cannot,
 * because a checker's approval raises no voucher of its own and leaves its only trace on the
 * verification row.
 */
@Component({
  selector: 'mifosx-my-work',
  templateUrl: './my-work.component.html',
  styleUrls: [
    '../cashier-shared.scss',
    './my-work.component.scss'
  ],
  standalone: true,
  imports: [
    CommonModule,
    FormsModule,
    MatIconModule,
    MatDialogModule
  ]
})
export class MyWorkComponent implements OnInit {
  private service = inject(CashierService);
  private dialog = inject(MatDialog);

  /** Which voucher's detail is currently being fetched, so the row that was clicked can show its
   *  own spinner instead of a page-wide one for what is a small, single-row lookup. */
  loadingDetailFor: string | null = null;

  /** Day is the working default; a month is what a close or an audit asks for. */
  period: 'DAY' | 'MONTH' = 'DAY';
  anchor = this.todayIso();

  /**
   * Narrow to one side, or to the part the user played. Both applied in the browser, and only to
   * the table below — the five summary tiles are pinned to Entered work regardless (see
   * enteredRows), so this can default to showing everything without muddying them.
   */
  sideFilter: '' | VoucherSide = '';
  roleFilter: '' | MyRole = '';

  report: MyWorkReport | null = null;
  loading = false;
  error: string | null = null;

  ngOnInit(): void {
    this.load();
  }

  load(): void {
    this.loading = true;
    this.error = null;

    const { from, to } = this.range();
    this.service
      .myVoucherWork(from, to)
      .pipe(
        catchError((err: any) => {
          this.error =
            err?.error?.errors?.[0]?.defaultUserMessage ??
            err?.error?.developerMessage ??
            'Your work for this period could not be loaded.';
          return of(null);
        })
      )
      .subscribe((res: MyWorkReport | null) => {
        this.loading = false;
        this.report = res;
      });
  }

  /**
   * The rows after the two on-screen filters.
   *
   * Filtered here rather than at the server: the day's own work is a small list, and narrowing it
   * without a round trip is what makes the filters feel like part of reading the page.
   */
  get rows(): MyWorkRow[] {
    const all = this.report?.vouchers ?? [];
    return all.filter(
      (r) => (!this.sideFilter || r.side === this.sideFilter) && (!this.roleFilter || r.myRole === this.roleFilter)
    );
  }

  /**
   * The rows split by the part the user played, each group with its own total.
   *
   * Entering a request and passing somebody else's are different jobs answerable to different
   * people, and a branch reads them separately: "what did I put through" is a maker's own tally,
   * "what did I let through" is a checker's. One list mixed them, so neither total could be read
   * off the page — a manager who entered one voucher and approved twenty saw twenty-one rows and
   * had to sort them by eye.
   *
   * An empty group is dropped rather than shown as a heading over nothing, so a clerk who never
   * approves anything sees one section and not a permanently empty second one.
   */
  get groups(): { key: MyRole; label: string; hint: string; rows: MyWorkRow[]; total: number }[] {
    const order: { key: MyRole; label: string; hint: string }[] = [
      { key: 'RAISED', label: 'Entered by me', hint: 'Requests and postings you put through' },
      { key: 'VERIFIED', label: 'Approved by me', hint: "Other people's work you passed" },
      {
        key: 'RAISED_AND_VERIFIED',
        label: 'Entered & approved by me',
        hint: 'Both roles on the same voucher — kept separate for the record'
      }
    ];
    return order
      .map((g) => {
        const rows = this.rows.filter((r) => r.myRole === g.key);
        return { ...g, rows, total: rows.reduce((sum, r) => sum + Number(r.amount ?? 0), 0) };
      })
      .filter((g) => g.rows.length > 0);
  }

  /** True when a filter is hiding part of what was loaded, so the count can say so. */
  get isFiltered(): boolean {
    return !!this.sideFilter || !!this.roleFilter;
  }

  clearFilters(): void {
    this.sideFilter = '';
    this.roleFilter = '';
  }

  /** The total of the rows on screen, which is not the day's total once a filter is on. */
  get filteredTotal(): number {
    return this.rows.reduce((sum, r) => sum + Number(r.amount ?? 0), 0);
  }

  /**
   * What this person themselves put through today — never narrowed by the Side or My part
   * filters, which exist only to browse the table below.
   *
   * The five summary tiles are pinned to this set on purpose. They answer one question, "what did
   * I personally do today", and that answer cannot depend on which slice of the list a person
   * happens to have the table filtered to at the moment — a Received figure that changed whenever
   * someone picked "Approved" to go look at what they'd passed would not be their own total any
   * more, it would be whatever the table was showing.
   */
  get enteredRows(): MyWorkRow[] {
    const all = this.report?.vouchers ?? [];
    return all.filter((r) => r.myRole === 'RAISED' || r.myRole === 'RAISED_AND_VERIFIED');
  }

  get receivedTotal(): number {
    return this.enteredRows.filter((r) => r.side === 'CR').reduce((sum, r) => sum + Number(r.amount ?? 0), 0);
  }

  get paymentTotal(): number {
    return this.enteredRows.filter((r) => r.side === 'DR').reduce((sum, r) => sum + Number(r.amount ?? 0), 0);
  }

  get journalTotal(): number {
    return this.enteredRows
      .filter((r) => r.side !== 'CR' && r.side !== 'DR')
      .reduce((sum, r) => sum + Number(r.amount ?? 0), 0);
  }

  get raisedCount(): number {
    return this.enteredRows.length;
  }

  get verifiedCount(): number {
    const all = this.report?.vouchers ?? [];
    return all.filter((r) => r.myRole === 'VERIFIED' || r.myRole === 'RAISED_AND_VERIFIED').length;
  }

  sideLabel(side: VoucherSide | null): string {
    if (side === 'CR') {
      return 'Received';
    }
    if (side === 'DR') {
      return 'Payment';
    }
    return 'Journal';
  }

  roleLabel(role: MyRole): string {
    if (role === 'RAISED') {
      return 'Entered';
    }
    if (role === 'VERIFIED') {
      return 'Approved';
    }
    return 'Entered & approved';
  }

  /**
   * Where the voucher stands, in words a branch uses.
   *
   * A voucher with no status at all is not unknown — it is a posting that never went through a
   * request: interest the nightly run credited, a charge taken from a balance. Those are done the
   * moment they exist, so they read as Posted rather than as a blank a reader has to interpret.
   */
  statusLabel(status: string | null): string {
    const s = (status ?? '').toUpperCase();
    if (!s) {
      return 'Posted';
    }
    if (s === 'WITHDRAWN') {
      return 'Paid out';
    }
    if (s === 'APPROVED') {
      return 'Approved';
    }
    if (s === 'PENDING') {
      return 'Pending';
    }
    if (s === 'REJECTED') {
      return 'Rejected';
    }
    if (s === 'CLOSED') {
      return 'Closed';
    }
    // OK / MISMATCH come from a physical cash verification rather than a request.
    return s.charAt(0) + s.slice(1).toLowerCase();
  }

  /**
   * Groups the statuses by what a reader does about them.
   *
   * 'paid' is kept apart from 'done' because approved and paid out are different facts: one is a
   * promise, the other is money gone. Sharing a colour hid exactly the thing somebody opens this
   * page to check.
   */
  statusClass(status: string | null): string {
    const s = (status ?? '').toUpperCase();
    if (s === 'PENDING') {
      return 'pending';
    }
    if (s === 'REJECTED' || s === 'MISMATCH') {
      return 'bad';
    }
    if (s === 'WITHDRAWN' || s === 'COMPLETED' || s === 'CLOSED') {
      return 'paid';
    }
    return 'done';
  }

  /**
   * A glyph per role, so the part played reads before the words do.
   *
   * A pen for an entry the user made, a tick for one they approved, and a warning for both on the
   * same voucher — which a small branch does legitimately, and an auditor should still see marked.
   */
  roleIcon(role: MyRole): string {
    if (role === 'RAISED') {
      return 'edit';
    }
    if (role === 'VERIFIED') {
      return 'check_circle';
    }
    return 'warning';
  }

  /** The period the anchor date names: that day, or the whole calendar month around it. */
  private range(): { from: string; to: string } {
    if (this.period === 'DAY') {
      return { from: this.anchor, to: this.anchor };
    }
    const [
      y,
      m
    ] = this.anchor.split('-').map(Number);
    const first = `${y}-${String(m).padStart(2, '0')}-01`;
    // Day 0 of the next month is the last day of this one, which avoids a table of month lengths
    // and gets February right in a leap year.
    const last = new Date(y, m, 0);
    const lastIso = `${last.getFullYear()}-${String(last.getMonth() + 1).padStart(2, '0')}-${String(
      last.getDate()
    ).padStart(2, '0')}`;
    return { from: first, to: lastIso };
  }

  /** Opens the full slip for one voucher — every debit and credit line, not just the first side of
   *  each a table row has room to show. */
  openDetail(voucherNo: string): void {
    if (this.loadingDetailFor) {
      return;
    }
    this.loadingDetailFor = voucherNo;
    this.service
      .voucherDetail(voucherNo)
      .pipe(
        catchError(() => of(null)),
        finalize(() => (this.loadingDetailFor = null))
      )
      .subscribe((detail: any) => {
        if (!detail) {
          return;
        }
        this.dialog.open(VoucherDetailDialogComponent, {
          data: { detail },
          width: '600px',
          autoFocus: false
        });
      });
  }

  private todayIso(): string {
    const d = new Date();
    return `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}-${String(d.getDate()).padStart(2, '0')}`;
  }
}