import { CurrencyPipe, DecimalPipe } from '@angular/common';
import { afterNextRender, Component, computed, effect, inject, input, linkedSignal, signal } from '@angular/core';
import { form, FormField, FormRoot } from '@angular/forms/signals';
import { MatAutocompleteModule } from '@angular/material/autocomplete';
import { MatButtonModule } from '@angular/material/button';
import { MatOptionModule } from '@angular/material/core';
import { MatDatepickerModule } from '@angular/material/datepicker';
import { MatDialog } from '@angular/material/dialog';
import { MatFormFieldModule } from '@angular/material/form-field';
import { MatIconModule } from '@angular/material/icon';
import { MatInputModule } from '@angular/material/input';
import { MatSelectModule } from '@angular/material/select';
import { MatSnackBar } from '@angular/material/snack-bar';
import { MatSortModule, Sort } from '@angular/material/sort';
import { MatTableModule } from '@angular/material/table';
import { Router } from '@angular/router';
import { round } from 'mathjs';
import moment from 'moment';

import { AuthService } from '../auth/auth.service';
import { Batch } from '../core/batch';
import { BatchService } from '../core/batch.service';
import { CostCentre } from '../core/cost-centre';
import { Inventory } from '../core/inventory';
import { User } from '../core/user';
import { Voucher } from '../core/voucher';
import { VoucherService } from '../core/voucher.service';
import { CostCentreService } from '../cost-centre/cost-centre.service';
import { ConfirmDialogComponent } from '../shared/confirm-dialog/confirm-dialog.component';
import { ErrorStateComponent } from '../shared/error-state/error-state.component';
import { LocalTimePipe } from '../shared/local-time.pipe';
import { MathService } from '../shared/math.service';
import { SkeletonLoaderComponent } from '../shared/skeleton-loader/skeleton-loader.component';
import { IssueDialogComponent } from './issue-dialog.component';
import { IssueGridService } from './issue-grid.service';

export interface IssueItemFormData {
  id: string | undefined;
  quantity: number;
  rate: number;
  tax: number;
  discount: number;
  amount: number;
  batch: Batch;
}

export interface IssueFormModel {
  date: Date;
  source: string;
  destination: string;
  amount: number;
  addRow: {
    batch: Batch | string | null;
    quantity: string;
  };
  inventories: IssueItemFormData[];
  narration: string;
  posted: boolean;
  creationDate: string;
  lastEditDate: string;
  userName: User;
  poster: string;
}

@Component({
  selector: 'app-issue',
  templateUrl: './issue.component.html',
  styleUrls: ['./issue.component.css'],
  host: {
    '(window:keydown.f2)': 'focusDate($event)',
    '(window:keydown.f3)': 'focusBatchHost($event)',
    '(window:keydown.control.s)': 'saveListner($event)',
    '(window:keydown.control.p)': 'postListner($event)',
  },
  imports: [
    FormField,
    FormRoot,
    MatFormFieldModule,
    MatInputModule,
    MatDatepickerModule,
    MatSelectModule,
    MatOptionModule,
    MatAutocompleteModule,
    MatIconModule,
    MatButtonModule,
    MatTableModule,
    MatSortModule,
    DecimalPipe,
    CurrencyPipe,
    LocalTimePipe,
    SkeletonLoaderComponent,
    ErrorStateComponent,
  ],
})
export class IssueComponent {
  private router = inject(Router);
  private dialog = inject(MatDialog);
  private snackBar = inject(MatSnackBar);
  auth = inject(AuthService);
  private math = inject(MathService);
  private ser = inject(VoucherService);
  private batchSer = inject(BatchService);
  private issueGridSer = inject(IssueGridService);
  private costCentreSer = inject(CostCentreService);
  sortActive = signal('');
  sortDirection = signal('');
  id = input(null, { transform: (v: string | null | undefined) => v ?? null });
  d = input(null, { transform: (v: string | null | undefined) => v ?? null });
  type = signal('Issue');
  itemResource = this.ser.getVoucher(this.id, this.type, signal(null), this.d);
  item = linkedSignal(() => this.itemResource.value() ?? new Voucher());

  formModel = linkedSignal<Voucher, IssueFormModel>({
    source: this.item,
    computation: (voucher): IssueFormModel => {
      const amount = round(
        voucher.inventories.reduce((p, c) => p + c.amount, 0),
        2,
      );
      return {
        date: voucher.date ? moment(voucher.date, 'DD-MMM-YYYY').toDate() : new Date(),
        source: (voucher.source as CostCentre)?.id ?? '',
        destination: (voucher.destination as CostCentre)?.id ?? '',
        amount,
        addRow: {
          batch: null as Batch | string | null,
          quantity: '',
        },
        inventories: voucher.inventories.map((inv) => ({
          id: inv.id,
          quantity: inv.quantity,
          rate: inv.rate,
          tax: inv.tax,
          discount: inv.discount,
          amount: inv.amount,
          batch: inv.batch,
        })),
        narration: voucher.narration ?? '',
        posted: voucher.posted,
        creationDate: voucher.creationDate,
        lastEditDate: voucher.lastEditDate,
        userName: voucher.user ?? new User(),
        poster: voucher.poster ?? '',
      };
    },
  });

  form = form(this.formModel);

  displayedColumns = ['product', 'batch', 'quantity', 'rate', 'amount', 'action'];
  gridColumns = ['source', 'destination', 'gridAmount', 'load'];

  balanceDate = computed(() => moment(this.form.date().value()).format('DD-MMM-YYYY'));

  batchSearch = computed(() => {
    const v = this.form.addRow.batch().value();
    return typeof v === 'string' ? v : null;
  });

  batchesResource = this.batchSer.autocomplete(this.balanceDate, this.batchSearch);
  batches = computed(() => this.batchesResource.value() ?? []);

  costCentresResource = this.costCentreSer.list();
  costCentres = computed(() => this.costCentresResource.value() ?? []);

  issueGridResource = this.issueGridSer.issueGrid(this.balanceDate);
  gridData = computed(() => this.issueGridResource.value() ?? []);

  focusDate(event: Event) {
    event.preventDefault();
    this.form().focusBoundControl();
  }

  focusBatchHost(event: Event) {
    event.preventDefault();
    this.form.addRow.batch().focusBoundControl();
  }

  saveListner(event: Event) {
    event.preventDefault();
    if (this.canSave()) {
      this.save();
    }
  }

  postListner(event: Event) {
    event.preventDefault();
    if (this.id() && !this.form.posted().controlValue() && this.auth.allowed('post-vouchers')) {
      this.post();
    }
  }

  constructor() {
    afterNextRender(() => {
      this.form.addRow.batch().focusBoundControl();
    });

    effect(() => {
      const d = this.formModel().date;
      if (!d) return;

      const url = new URL(window.location.href);
      url.searchParams.set('d', moment(d).format('DD-MMM-YYYY'));
      window.history.replaceState({}, '', url.toString());
    });
  }

  displayFn(batch?: Batch | string): string {
    return !batch ? '' : typeof batch === 'string' ? batch : batch.name;
  }

  addRow() {
    const formValue = this.form().value().addRow;
    if (!formValue || !formValue.batch || typeof formValue.batch === 'string') {
      return;
    }
    const batch = formValue.batch as Batch;
    const quantity = this.math.parseAmount(formValue.quantity ?? '0', 2);
    const isConsumption = this.formModel().source === '7b845f95-dfef-fa4a-897c-f0baf15284a3';
    if (quantity <= 0) {
      return;
    }
    const currentInventories = this.formModel().inventories;
    const oldIndex = currentInventories.findIndex((x) => x.batch?.id === batch.id);
    let updatedInventories: IssueItemFormData[];
    if (oldIndex >= 0) {
      const old = currentInventories[oldIndex];
      if (isConsumption && old.quantity + quantity > batch.quantityRemaining) {
        this.snackBar.open('Quantity issued cannot be more than quantity available', 'Danger');
        return;
      }
      const newQty = old.quantity + quantity;
      const newAmount = round(newQty * batch.rate * (1 + batch.tax) * (1 - batch.discount), 2);
      updatedInventories = currentInventories.map((inv, i) =>
        i === oldIndex ? { ...inv, quantity: newQty, amount: newAmount } : inv,
      );
    } else {
      if (isConsumption && quantity > batch.quantityRemaining) {
        this.snackBar.open('Quantity issued cannot be more than quantity available', 'Danger');
        return;
      }
      const newRow: IssueItemFormData = {
        id: undefined,
        quantity,
        rate: batch.rate,
        tax: batch.tax,
        discount: batch.discount,
        amount: round(quantity * batch.rate * (1 + batch.tax) * (1 - batch.discount), 2),
        batch,
      };
      updatedInventories = [...currentInventories, newRow];
    }
    const totalAmount = round(
      updatedInventories.reduce((p, c) => p + c.amount, 0),
      2,
    );
    this.formModel.update((m) => ({
      ...m,
      inventories: updatedInventories,
      amount: totalAmount,
    }));
    this.form.addRow.batch().value.set(null);
    this.form.addRow.quantity().value.set('');
    this.form.addRow.batch().focusBoundControl();
  }

  deleteRow(row: IssueItemFormData) {
    const updatedInventories = this.formModel().inventories.filter((j) => j !== row);
    const totalAmount = round(
      updatedInventories.reduce((p, c) => p + c.amount, 0),
      2,
    );
    this.formModel.update((m) => ({
      ...m,
      inventories: updatedInventories,
      amount: totalAmount,
    }));
    this.form.addRow.batch().focusBoundControl();
  }

  editRow(row: IssueItemFormData) {
    const dialogRef = this.dialog.open(IssueDialogComponent, {
      width: '750px',
      data: {
        inventory: new Inventory({
          id: row.id,
          quantity: row.quantity,
          rate: row.rate,
          tax: row.tax,
          discount: row.discount,
          amount: row.amount,
          batch: row.batch,
        }),
        date: moment(this.formModel().date).format('DD-MMM-YYYY'),
      },
    });

    dialogRef.afterClosed().subscribe((result: boolean | Inventory) => {
      if (!result || typeof result === 'boolean') {
        return;
      }
      const j = result;
      if (
        j.batch?.sku.id !== row.batch?.sku.id &&
        this.formModel().inventories.some((x) => x.batch?.id === j.batch?.id)
      ) {
        this.snackBar.open('Product already added', 'Danger');
        return;
      }
      const updatedInventories = this.formModel().inventories.map((item) =>
        item === row
          ? {
              ...item,
              quantity: j.quantity,
              rate: j.rate,
              tax: j.tax,
              discount: j.discount,
              amount: j.amount,
              batch: j.batch,
            }
          : item,
      );
      const totalAmount = round(
        updatedInventories.reduce((p, c) => p + c.amount, 0),
        2,
      );
      this.formModel.update((m) => ({
        ...m,
        inventories: updatedInventories,
        amount: totalAmount,
      }));
      this.form.addRow.batch().focusBoundControl();
    });
  }

  getVoucher(): Voucher {
    const m = this.formModel();
    const base = this.item();
    const v = new Voucher({ ...base });
    v.date = moment(m.date).format('DD-MMM-YYYY');
    v.source = new CostCentre({ id: m.source });
    v.destination = new CostCentre({ id: m.destination });
    v.narration = m.narration ?? '';
    v.inventories = m.inventories.map(
      (inv) =>
        new Inventory({
          id: inv.id,
          quantity: inv.quantity,
          rate: inv.rate,
          tax: inv.tax,
          discount: inv.discount,
          amount: inv.amount,
          batch: inv.batch,
        }),
    );
    return v;
  }

  canSave() {
    if (!this.id()) {
      return true;
    }
    if (this.form.posted().value() && !this.auth.allowed('edit-posted-vouchers')) {
      return false;
    }
    const user = this.auth.user as User;
    return this.item().user?.id === user?.id || this.auth.allowed("edit-other-user's-vouchers");
  }

  save() {
    this.ser.saveOrUpdate(this.getVoucher()).subscribe({
      next: (result) => {
        this.snackBar.open('Voucher Saved', undefined, { duration: 2000 });
        if (this.item().id === result.id) {
          this.item.set(result);
        } else {
          this.router.navigate(['/issue', result.id]);
        }
      },
      error: (error) => {
        this.snackBar.open(error, 'Danger');
      },
    });
  }

  post() {
    const id = this.id();
    if (id) {
      this.ser.post(id).subscribe({
        next: (result) => {
          this.snackBar.open('Voucher Posted', undefined, { duration: 2000 });
          this.item.set(result);
        },
        error: (error) => {
          this.snackBar.open(error, 'Danger');
        },
      });
    }
  }

  newVoucher() {
    this.router.navigate(['/issue']);
  }

  confirmDelete(): void {
    const id = this.id();
    if (!id) return;
    const dialogRef = this.dialog.open(ConfirmDialogComponent, {
      data: { title: 'Delete Voucher?', content: 'Are you sure? This cannot be undone.' },
    });

    dialogRef.afterClosed().subscribe((result) => {
      if (result) {
        this.delete();
      }
    });
  }

  delete() {
    const id = this.id();
    if (id) {
      this.ser.delete(id).subscribe({
        next: () => {
          this.snackBar.open('Voucher Deleted', undefined, { duration: 2000 });
          this.router.navigate(['/issue'], { replaceUrl: true });
        },
        error: (error) => {
          this.snackBar.open(error, 'Danger');
        },
      });
    }
  }

  goToVoucher(id: string) {
    this.router.navigate(['/issue', id]);
  }

  sortData(sort: Sort) {
    this.sortActive.set(sort.active);
    this.sortDirection.set(sort.direction);
  }
}