import {Component, EventEmitter, Input, Output} from '@angular/core';
import {Field, FieldType, Operator, Predicate, Query} from "../query-builder/query-builder.component";
import {JsonPipe, NgForOf, NgIf} from "@angular/common";
import {FormsModule, ReactiveFormsModule} from "@angular/forms";
import { v4 as uuidv4 } from 'uuid';

@Component({
  selector: 'app-query',
  standalone: true,
  imports: [
    NgForOf,
    ReactiveFormsModule,
    FormsModule,
    NgIf,
    JsonPipe
  ],
  templateUrl: './query.component.html',
  styleUrl: './query.component.css'
})
export class QueryComponent {

  @Input() query!: Query;
  @Input() fields!: Field[];

  @Output() removeQuery = new EventEmitter<void>();
  @Output() queryChanged = new EventEmitter<void>();

  queryId = uuidv4();

  constructor() {}

  onFieldChange(predicate: Predicate, selectedField: any): void {
    predicate.field = selectedField;
    predicate.operator = this.getOperators(selectedField.type)[0];
  }

  getOperators(fieldType: FieldType | undefined): Operator[] {
    switch (fieldType) {
      case 'number':
        return ['=', '>', '<', '>=', '<=', '!=']
          .map((operatorType: String) => ({ operatorType: operatorType, acceptsValues: 'any'}) as Operator);
      case 'string':
        return ['=', 'contains', 'like']
          .map((operatorType: String) => ({ operatorType: operatorType, acceptsValues: 'any'}) as Operator);
      case 'boolean':
        return ['=', '!=']
          .map((operatorType: String) => ({ operatorType: operatorType, acceptsValues: 'boolean'}) as Operator);
      case 'flag':
        return ['=', '!=']
          .map((operatorType: String) => ({ operatorType: operatorType, acceptsValues: 'flag'}) as Operator);
        case 'grade':
        return ['=', '!=']
          .map((operatorType: String) => ({ operatorType: operatorType, acceptsValues: 'grade'}) as Operator);
      default:
        return [];
    }
  }

  addPredicate(): void {
    this.query.predicates.push({ field: null, operator: null, value: null });
    this.queryChanged.emit();
  }

  removePredicate(index: number): void {
    this.query.predicates.splice(index, 1);
    this.queryChanged.emit();
  }

  addSubQuery(): void {
    if (!this.query.childQueries) {
      this.query.childQueries = [];
    }
    this.query.childQueries.push({ predicates: [], logicalOperator: 'AND' });
    this.queryChanged.emit();
  }

  removeSubQuery(index: number): void {
    // @ts-ignore
    this.query.childQueries.splice(index, 1);
    this.queryChanged.emit();
  }

}