import { AfterViewInit, Component, ElementRef, OnInit, ViewChild } from '@angular/core';
import { FormBuilder, FormGroup } from '@angular/forms';
import { MatAutocompleteSelectedEvent } from '@angular/material/autocomplete';
import { MatDialog } from '@angular/material/dialog';
import { ActivatedRoute, Router } from '@angular/router';
import * as moment from 'moment';
import { BehaviorSubject, Observable, of as observableOf } from 'rxjs';
import { debounceTime, distinctUntilChanged, map, startWith, switchMap } from 'rxjs/operators';

import { AuthService } from '../auth/auth.service';
import { EmployeeBenefit } from '../core/employee-benefit';
import { ToasterService } from '../core/toaster.service';
import { Voucher } from '../core/voucher';
import { VoucherService } from '../core/voucher.service';
import { Employee } from '../employee/employee';
import { EmployeeService } from '../employee/employee.service';
import { ConfirmDialogComponent } from '../shared/confirm-dialog/confirm-dialog.component';

import { EmployeeBenefitsDataSource } from './employee-benefits-datasource';

@Component({
  selector: 'app-employee-benefits',
  templateUrl: './employee-benefits.component.html',
  styleUrls: ['./employee-benefits.component.css'],
})
export class EmployeeBenefitsComponent implements OnInit, AfterViewInit {
  @ViewChild('employeeElement', { static: true }) employeeElement?: ElementRef;
  public benefitsObservable = new BehaviorSubject<EmployeeBenefit[]>([]);
  dataSource: EmployeeBenefitsDataSource;
  form: FormGroup;
  voucher: Voucher;
  employee: Employee;
  accBal: any;

  displayedColumns = [
    'name',
    'designation',
    'department',
    'grossSalary',
    'daysWorked',
    'esiEmployee',
    'pfEmployee',
    'esiEmployer',
    'pfEmployer',
  ];

  employees: Observable<Employee[]>;

  constructor(
    private route: ActivatedRoute,
    private router: Router,
    private fb: FormBuilder,
    private dialog: MatDialog,
    private toaster: ToasterService,
    public auth: AuthService,
    private ser: VoucherService,
    private employeeSer: EmployeeService,
  ) {
    this.form = this.fb.group({
      date: '',
      addRow: this.fb.group({
        employee: '',
        grossSalary: '',
        daysWorked: '',
      }),
    });
    this.setupEmployeeAutocomplete();
  }

  static getPf(grossSalary, daysWorked, daysInMonth) {
    const limit = 15000;
    const employeeRate = 0.12;
    const employerRate = 0.12 + 0.011 + 0.005 + 0.0001;
    const employee =
      grossSalary > limit ? 0 : Math.ceil((employeeRate * grossSalary * daysWorked) / daysInMonth);
    const employer =
      grossSalary > limit ? 0 : Math.ceil((employerRate * grossSalary * daysWorked) / daysInMonth);
    return { ee: employee, er: employer, both: employee + employer };
  }

  static getEsi(grossSalary, daysWorked, daysInMonth) {
    const limit = 21000;
    const employeeRate = 0.0175;
    const employerRate = 0.0475;
    const employee =
      grossSalary > limit ? 0 : Math.ceil((employeeRate * grossSalary * daysWorked) / daysInMonth);
    const employer =
      grossSalary > limit ? 0 : Math.ceil((employerRate * grossSalary * daysWorked) / daysInMonth);
    return { ee: employee, er: employer, both: employee + employer };
  }

  ngOnInit() {
    this.route.data.subscribe((value) => {
      const data = value as { voucher: Voucher };

      this.loadVoucher(data.voucher);
    });
  }

  ngAfterViewInit() {
    setTimeout(() => {
      this.employeeElement.nativeElement.focus();
    }, 0);
  }

  loadVoucher(voucher) {
    this.voucher = voucher;
    this.form.setValue({
      date: moment(this.voucher.date, 'DD-MMM-YYYY').toDate(),
      addRow: {
        employee: '1',
        grossSalary: '',
        daysWorked: '',
      },
    });
    this.dataSource = new EmployeeBenefitsDataSource(this.benefitsObservable);
    this.benefitsObservable.next(this.voucher.employeeBenefits);
  }

  setupEmployeeAutocomplete(): void {
    const control = this.form.get('addRow').get('employee');
    this.employees = control.valueChanges.pipe(
      startWith(null),
      map((x) => (x !== null && x.length >= 1 ? x : null)),
      debounceTime(150),
      distinctUntilChanged(),
      switchMap((x) => (x === null ? observableOf([]) : this.employeeSer.autocomplete(x))),
    );
  }

  displayFn(employee?: Employee): string | undefined {
    return employee ? employee.name : undefined;
  }

  employeeSelected(event: MatAutocompleteSelectedEvent): void {
    this.employee = event.option.value;
  }

  addRow() {
    const oldFiltered = this.voucher.employeeBenefits.filter(
      (x) => x.employee.id === this.employee.id,
    );
    if (oldFiltered.length) {
      this.toaster.show('Danger', 'Employee has already been added');
      return;
    }

    const formValue = this.form.get('addRow').value;
    const grossSalary = +formValue.grossSalary;
    const daysWorked = +formValue.daysWorked;
    const date = this.form.get('date').value;
    const daysInMonth = moment(date).daysInMonth();
    const esi = EmployeeBenefitsComponent.getEsi(grossSalary, daysWorked, daysInMonth);
    const pf = EmployeeBenefitsComponent.getPf(grossSalary, daysWorked, daysInMonth);

    this.voucher.employeeBenefits.push({
      employee: this.employee,
      grossSalary,
      daysWorked,
      esiEmployee: esi.ee,
      pfEmployee: pf.ee,
      esiEmployer: esi.er,
      pfEmployer: pf.er,
    });
    this.benefitsObservable.next(this.voucher.employeeBenefits);
    this.resetAddRow();
  }

  resetAddRow() {
    this.form.get('addRow').reset({
      employee: '',
      grossSalary: null,
      daysWorked: null,
    });
    this.employee = null;
    setTimeout(() => {
      this.employeeElement.nativeElement.focus();
    }, 0);
  }

  deleteRow(row: EmployeeBenefit) {
    this.voucher.employeeBenefits.splice(this.voucher.employeeBenefits.indexOf(row), 1);
    this.benefitsObservable.next(this.voucher.employeeBenefits);
  }

  canSave() {
    if (!this.voucher.id) {
      return true;
    }
    if (this.voucher.posted && this.auth.user.perms.indexOf('edit-posted-vouchers') !== -1) {
      return true;
    }
    return (
      this.voucher.user.id === this.auth.user.id ||
      this.auth.user.perms.indexOf("edit-other-user's-vouchers") !== -1
    );
  }

  post() {
    this.ser.post(this.voucher.id).subscribe(
      (result) => {
        this.loadVoucher(result);
        this.toaster.show('Success', 'Voucher Posted');
      },
      (error) => {
        this.toaster.show('Danger', error);
      },
    );
  }

  save() {
    const voucher: Voucher = this.getVoucher();
    this.ser.saveOrUpdate(voucher).subscribe(
      (result) => {
        this.toaster.show('Success', '');
        if (voucher.id === result.id) {
          this.loadVoucher(result);
        } else {
          this.router.navigate(['/employee-benefits', result.id]);
        }
      },
      (error) => {
        this.toaster.show('Danger', error);
      },
    );
  }

  getVoucher(): Voucher {
    const formModel = this.form.value;
    this.voucher.date = moment(formModel.date).format('DD-MMM-YYYY');
    return this.voucher;
  }

  delete() {
    this.ser.delete(this.voucher.id).subscribe(
      () => {
        this.toaster.show('Success', '');
        this.router.navigate(['/employee-benefits'], { replaceUrl: true });
      },
      (error) => {
        this.toaster.show('Danger', error);
      },
    );
  }

  confirmDelete(): void {
    const dialogRef = this.dialog.open(ConfirmDialogComponent, {
      width: '250px',
      data: { title: 'Delete Voucher?', content: 'Are you sure? This cannot be undone.' },
    });

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