import { ChangeDetectionStrategy, Component, computed, input, output } from '@angular/core';
import { CheckboxField, DateField, LookupField, NumberField, SelectField, TextField, TextareaField, UdfField } from '../../shared/form';
import { WAREHOUSE_LOOKUP } from '../documents/document-layouts';
import type { VhLookup } from '../../shared/value-help/value-help.types';
import type { HeaderField } from '../documents/document-layouts';

const text = (v: unknown): string => (v === null || v === undefined ? '' : String(v));

/**
 * Dibuja un campo de un formulario de maestro según su tipo. Recibe el valor tal como está en SAP
 * (las casillas son `tYES` / `tNO`) y emite el nuevo valor en esa misma forma.
 */
@Component({
  selector: 'sbo-master-field',
  changeDetection: ChangeDetectionStrategy.OnPush,
  imports: [CheckboxField, DateField, LookupField, NumberField, SelectField, TextField, TextareaField, UdfField],
  template: `
    @switch (field().type) {
      @case ('checkbox') {
        <sbo-checkbox-field
          [label]="field().label" [dbName]="dbName()"
          [readonly]="readOnly() || !!ro()"
          [value]="value() === 'tYES'"
          (valueChange)="changed.emit($event ? 'tYES' : 'tNO')"
        />
      }
      @case ('lookup') {
        <sbo-lookup-field
          [label]="field().label" [dbName]="dbName()"
          [required]="required()"
          [readonly]="readOnly()"
          [value]="str()"
          (valueChange)="changed.emit(typed($event))"
          [lookup]="lookup()"
          resolveOnLeave
        />
      }
      @case ('warehouse') {
        <sbo-lookup-field
          [label]="field().label" [dbName]="dbName()"
          [required]="required()"
          [readonly]="readOnly()"
          [value]="str()"
          (valueChange)="changed.emit($event)"
          [lookup]="warehouse"
          resolveOnLeave
        />
      }
      @case ('udf') {
        <sbo-udf-field
          [label]="field().label" [dbName]="dbName()"
          [table]="udf().table" [alias]="udf().alias"
          [required]="required()"
          [readonly]="readOnly() || !!ro()"
          [value]="value()"
          (valueChange)="changed.emit($any($event))"
        />
      }
      @case ('select') {
        <sbo-select-field
          [label]="field().label" [dbName]="dbName()"
          [required]="required()"
          [readonly]="readOnly()"
          [options]="options()"
          placeholder=""
          [value]="str() || null"
          (valueChange)="changed.emit($event ?? '')"
        />
      }
      @case ('number') {
        <sbo-number-field
          [label]="field().label" [dbName]="dbName()"
          [decimals]="decimals()"
          [readonly]="readOnly() || !!ro()"
          [value]="num()"
          (valueChange)="changed.emit($event ?? 0)"
        />
      }
      @case ('date') {
        <sbo-date-field [label]="field().label" [dbName]="dbName()" [required]="required()" [readonly]="readOnly()" [value]="str()" (valueChange)="changed.emit($event)" />
      }
      @case ('textarea') {
        <sbo-textarea-field [label]="field().label" [dbName]="dbName()" [readonly]="readOnly()" [value]="str()" (valueChange)="changed.emit($event)" />
      }
      @default {
        <sbo-text-field
          [label]="field().label" [dbName]="dbName()"
          [required]="required()"
          [readonly]="readOnly() || !!ro()"
          [value]="str()"
          (valueChange)="changed.emit($event)"
        />
      }
    }
  `,
  styles: ':host { display: block; }',
})
export class MasterField {
  readonly field = input.required<HeaderField>();
  readonly value = input<unknown>('');
  /** Todo el formulario en solo lectura. */
  readonly readOnly = input(false);
  /** El registro ya existe: los campos `immutable` (el código) no se pueden cambiar. */
  readonly saved = input(false);
  readonly changed = output<string | number>();

  protected readonly udf = computed(() => {
    const f = this.field();
    if (f.type !== 'udf') throw new Error('campo sin definición de usuario');
    return f;
  });

  protected readonly warehouse: VhLookup = { ...WAREHOUSE_LOOKUP, nameKey: 'WarehouseName' };

  /** Un código numérico de SAP (grupo, lista de precios) se guarda como número. */
  protected typed(code: string): string | number {
    const f = this.field();
    return f.type === 'lookup' && f.lookup.valueType === 'number' && /^\d+$/.test(code.trim()) ? Number(code) : code;
  }
  /** El texto del campo; una fecha de SAP llega como `2031-10-31T00:00:00Z` y el selector de fecha pide `yyyy-MM-dd`. */
  protected readonly dbName = computed(() => {
    const f = this.field();
    return 'key' in f ? f.key : undefined;
  });
  protected readonly str = computed(() => (this.field().type === 'date' ? text(this.value()).slice(0, 10) : text(this.value())));
  protected readonly num = computed(() => (this.value() === '' || this.value() === null || this.value() === undefined ? null : Number(this.value())));
  protected readonly required = computed(() => {
    const f = this.field();
    return 'required' in f && f.required === true;
  });
  protected readonly ro = computed(() => {
    const f = this.field();
    if ('immutable' in f && f.immutable && this.saved()) return true;
    return 'readonly' in f ? !!f.readonly : false;
  });
  protected readonly lookup = computed(() => {
    const f = this.field();
    if (f.type !== 'lookup') throw new Error('campo sin lista de valores');
    return f.lookup;
  });
  protected readonly options = computed(() => {
    const f = this.field();
    return f.type === 'select' ? f.options : [];
  });
  protected readonly decimals = computed(() => {
    const f = this.field();
    return f.type === 'number' ? f.decimals : undefined;
  });
}