import { Category } from './../../../../shared/models/category.interface';
import { Component, Input, OnInit } from '@angular/core';
import { FormBuilder, Validators, FormGroup } from '@angular/forms';
import { DocumentClassification } from 'src/app/shared/models/document-classification.interface';
import { CategoriesService } from 'src/app/shared/services/administration/categories.service';
import { DocumentClassificationsService } from 'src/app/shared/services/administration/document-classifications.service';
import { ErrorHandlingService } from 'src/app/shared/services/error-handling/error-handling.service';

@Component({
  selector: 'app-category-form',
  templateUrl: './category-form.component.html',
  styleUrls: ['./category-form.component.scss']
})
export class CategoryFormComponent implements OnInit {

  /*
   * Inputs
   */
  @Input() dialogLayout: boolean = false;   // Controls .scss classes to allow for better dispay in a dialog.
  @Input() requiredFields: string[] | boolean = false;  // True/False indicates that all/none are required. String[] specifies the form controls required.
  @Input() displayValidationMessagesEvenIfPristine: boolean = false;  // Serves for manually treating the controls as dirty.
  @Input() autosuggestInputs: boolean = false;

  /*
   * Reactive Form
   */
  categoryForm = this.fb.group({
    documentClassification: [null],
    categoryName: [null],
    categoryCode: [null]
  });

  setFormValue: Category = null;
  selectedCategory: Category;

  /*
   * Other Variables
   */
  documentClassificationsList: DocumentClassification[];

  categoryNameSuggestions: string[];
  categoryCodeSuggestions: string[];
  categorySuggestions: Category[];

  /*
   * Constructor & Initialisers
   */
  constructor(
    private fb: FormBuilder,
    private categoriesService: CategoriesService,
    private documentClassificationsService: DocumentClassificationsService,
    private errorHandlingService: ErrorHandlingService
  ) { }

  ngOnInit(): void {
    this.initData();
    this.initValidators()
  }

  initData() {
    this.documentClassificationsService.getAll().subscribe(
      value => this.documentClassificationsList = value,
      err => this.errorHandlingService.showHttpResponseError(err)
    );
  }

  // TODO: Have this mechanism offer the use of custom validators too.
  initValidators() {

    if (!this.requiredFields) { return; }

    // In a true/false case.
    if (typeof this.requiredFields == 'boolean') {
      // If true, enable the required validator for all controls and sub-controls.
      if (this.requiredFields) {
        this.setRequiredValidatorRecursively(this.categoryForm);
      }

      // If false, do nothing.
      return;
    }

    // If it was a string array, enable the validators for all provided field-names. TODO: This ONLY supports 1st level controls and not nested ones.
    (<string[]>this.requiredFields).forEach(field => this.categoryForm.controls[field].setValidators(Validators.required))
  }

  setRequiredValidatorRecursively(group: FormGroup) {
    Object.keys(group.controls).forEach(key => {
      group.controls[key].setValidators(Validators.required);

      if (group.controls[key]['controls']) {
        this.setRequiredValidatorRecursively(<FormGroup>group.controls[key])
      }
    });
  }

  /*
   * Auto-suggest & Auto-complete Category
   */
  autosuggestCategoryName(event) {

    if (!event.query || event.query.length < 3) {
      this.categoryNameSuggestions = [];
      return;
    }

    let classId = this.categoryForm.get('documentClassification').value ? this.categoryForm.get('documentClassification').value.classificationId : null;
    this.categoriesService.autosuggestCategoryName(event.query, classId).subscribe(
      (values: Category[]) => {
        let temp: string[] = [];
        this.categorySuggestions = values;
        values.map(val => temp.push(val.categoryName));
        this.categoryNameSuggestions = temp
      },
      err => this.errorHandlingService.showHttpResponseError(err)
    );
  }

  autosuggestCategoryCode(event) {

    if (event.query.length < 3) {
      this.categoryCodeSuggestions = [];
      return;
    }

    let classId = this.categoryForm.get('documentClassification').value ? this.categoryForm.get('documentClassification').value.classificationId : null;
    this.categoriesService.autosuggestCategoryCode(event.query, classId).subscribe(
      (values: Category[]) => {
        let temp: string[] = [];
        this.categorySuggestions = values;
        values.map(val => temp.push(val.categoryCode));
        this.categoryCodeSuggestions = temp
      },
      err => this.errorHandlingService.showHttpResponseError(err)
    );
  }

  categoryNameSelected(name: string) {
    this.selectedCategory = this.categorySuggestions.find(cat => cat.categoryName == name);
    this.categoryForm.get('categoryCode').patchValue(this.selectedCategory.categoryCode);
    this.categoryForm.updateValueAndValidity();
  }

  categoryCodeSelected(code: string) {
    this.selectedCategory = this.categorySuggestions.find(cat => cat.categoryCode == code);
    this.categoryForm.get('categoryName').patchValue(this.selectedCategory.categoryName);
    this.categoryForm.updateValueAndValidity();
  }

  /*
   * API methods
   */
  public resetForm(): void {
    this.categoryForm.reset();
  }

  public formValue(): Category {
    let formValue: Category = {
      id: this.setFormValue ? this.setFormValue.id : null,
      documentClassification: this.categoryForm.get('documentClassification').value,
      categoryName: this.categoryForm.get('categoryName').value,
      categoryCode: this.categoryForm.get('categoryCode').value
    };

    return formValue;
  }

  public setValue(value: Category): void {
    if (!value) {
      return;
    }

    this.setFormValue = value;
    this.categoryForm.get('documentClassification').setValue(value.documentClassification);
    this.categoryForm.get('categoryName').setValue(value.categoryName);
    this.categoryForm.get('categoryCode').setValue(value.categoryCode);
    this.categoryForm.updateValueAndValidity();
  }

  public isValid(): boolean {
    return this.categoryForm.valid;
  }
}