import {ChangeDetectorRef, Component, Input, OnInit} from '@angular/core';
import {EnvProperties} from '../../../openaireLibrary/utils/properties/env-properties';
import {
  Constraint,
  ContentProvider,
  Criteria,
  SelectionCriteria
} from '../../../openaireLibrary/utils/entities/contentProvider';
import {AbstractControl, UntypedFormArray, UntypedFormBuilder, UntypedFormGroup, Validators} from '@angular/forms';
import {ManageCommunityContentProvidersService} from '../../../services/manageContentProviders.service';
import {properties} from "../../../../environments/environment";
import {Option} from "../../../openaireLibrary/sharedComponents/input/input.component";
import {MatSlideToggleChange} from "@angular/material/slide-toggle";
import {HelperFunctions} from "../../../openaireLibrary/utils/HelperFunctions.class";
import {CriteriaUtils} from "../criteria-utils";
import {NotificationHandler} from "../../../openaireLibrary/utils/notification-handler";
import {OpenaireEntities} from "../../../openaireLibrary/utils/properties/searchFields";

@Component({
  selector: 'criteria',
  templateUrl: 'criteria.component.html',
  styleUrls: ['criteria.component.less']
})
export class CriteriaComponent implements OnInit {
  @Input()
  public dataProvider: ContentProvider;
  public selectionCriteria: UntypedFormGroup;
  public properties: EnvProperties = properties;
  public fields: Option[] = CriteriaUtils.fields;
  public verbs: Option[] = CriteriaUtils.verbs;
  public loading = true;
  /** Paging */
  public page: number = 1;
  public pageSize: number = 5;
  public openaireEntities = OpenaireEntities;
  
  constructor(private manageCommunityContentProvidersService: ManageCommunityContentProvidersService,
              private cdr: ChangeDetectorRef,
              private fb: UntypedFormBuilder) {
  }
  
  ngOnInit() {
    this.reset();
    this.loading = false;
  }
  
  reset() {
    this.page = 1;
    if (this.dataProvider) {
      this.selectionCriteria = this.fb.group({
        criteria: this.fb.array([])
      });
      let selectionCriteria = this.dataProvider.selectioncriteria;
      if (selectionCriteria) {
        selectionCriteria.criteria.forEach(criterion => {
          let constraintArray: UntypedFormArray = this.fb.array([]);
          criterion.constraint.forEach(constraint => {
            constraintArray.push(this.fb.group({
              field: this.fb.control(constraint.field, Validators.required),
              verb: this.fb.control(this.removeSuffix(constraint.verb), Validators.required),
              value: this.fb.control(constraint.value, Validators.required),
              verb_suffix: this.fb.control(this.getSuffix(constraint.verb))
            }));
          });
          this.criteria.push(this.fb.group({
            constraint: constraintArray
          }));
        });
      }
    }
  }
  
  get disabled() {
    return this.loading || !this.dirty || this.selectionCriteria.invalid;
  }
  
  get currentPage(): AbstractControl[] {
    if (this.criteria) {
      return this.criteria.controls.slice((this.page - 1) * this.pageSize, this.page * this.pageSize);
    } else {
      return [];
    }
  }
  
  getIndex(index: number): number {
    return (this.page - 1)*this.pageSize + index;
  }
  
  public get criteria(): UntypedFormArray {
    return this.selectionCriteria.get('criteria') as UntypedFormArray;
  }
  
  public getConstraint(i: number): UntypedFormArray {
    return this.criteria.at(i).get('constraint') as UntypedFormArray;
  }
  
  public addCriteria() {
    let constraintArray: UntypedFormArray = this.fb.array([
      this.fb.group({
        field: this.fb.control('', Validators.required),
        verb: this.fb.control('contains', Validators.required),
        value: this.fb.control('', Validators.required),
        verb_suffix: this.fb.control('_caseinsensitive')
      })
    ]);
    this.criteria.insert(0, this.fb.group({
      constraint: constraintArray
    }));
    this.page = 1;
    this.cdr.detectChanges();
  }
  
  public addConstraint(i: number) {
    let constraintArray: UntypedFormArray = this.criteria.at(i).get('constraint') as UntypedFormArray;
    constraintArray.push(this.fb.group({
      field: this.fb.control('', Validators.required),
      verb: this.fb.control('contains', Validators.required),
      value: this.fb.control('', Validators.required),
      verb_suffix: this.fb.control('_caseinsensitive')
    }));
    this.cdr.detectChanges();
  }
  
  public removeConstraint(i: number, j: number) {
    let constraintArray: UntypedFormArray = this.criteria.at(i).get('constraint') as UntypedFormArray;
    constraintArray.removeAt(j);
    if (constraintArray.length === 0) {
      this.criteria.removeAt(i);
      while(this.currentPage.length === 0 && this.page > 0) {
        this.page--;
      }
    }
    this.cdr.detectChanges();
  }
  
  get dataProviderCriteria(): Criteria[] {
    return (this.dataProvider && this.dataProvider.selectioncriteria && this.dataProvider.selectioncriteria.criteria)?this.dataProvider.selectioncriteria.criteria:[];
  }

  get dirty() {
    if(!this.dataProvider || !this.criteria) {
      return false;
    } else if(this.criteria.length !== this.dataProviderCriteria.length) {
      return true;
    } else {
      return this.dataProviderCriteria.filter((criterion, i) => {
        if(criterion.constraint.length !== this.getConstraint(i).length) {
          return true;
        } else {
          let temp = this.getConstraint(i).value;
          return criterion.constraint.filter((constraint, j) => {
            return constraint.field !== temp[j].field || constraint.verb !== (temp[j].verb + temp[j].verb_suffix) || constraint.value !== temp[j].value;
          }).length > 0;
        }
      }).length > 0;
    }
  }
  
  save(callback: Function = null) {
    if (this.selectionCriteria.valid) {
      this.loading = true;
      this.dataProvider.selectioncriteria = this.parseForm(this.selectionCriteria.value);
      this.manageCommunityContentProvidersService.saveContentProvider(this.properties, this.dataProvider).subscribe(() => {
        this.reset();
        if(callback)  {
          callback();
        }
        this.loading = false;
        NotificationHandler.rise('Filters have been <b>successfully updated</b>');
      }, error => {
        this.loading = false;
        this.handeError('An error has been occurred. Try again later!', error);
      });
    } else {
      this.handeError('An error has been occurred. Try again later!');
    }
  }
  
  handeError(message, error = null) {
    console.error(error);
    NotificationHandler.rise(message, 'danger');
  }
  
  caseSensitive(event: MatSlideToggleChange, constraint: AbstractControl) {
    if(event.checked) {
      constraint.get('verb_suffix').setValue('');
    } else {
      constraint.get('verb_suffix').setValue('_caseinsensitive');
    }
  }
  
  removeSuffix(verb: string) {
    return verb.replace('_caseinsensitive', '');
  }
  
  getSuffix(verb: string) {
    if(verb.includes('_caseinsensitive')) {
      return '_caseinsensitive';
    } else {
      return '';
    }
  }
  
  parseForm(formValue): SelectionCriteria {
    let value = HelperFunctions.copy(formValue);
    let selectionCriteria: SelectionCriteria = new SelectionCriteria();
    selectionCriteria.criteria = [];
    value.criteria.forEach(criterion => {
      let criteria = new Criteria();
      criteria.constraint = [];
      criterion.constraint.forEach(constraint => {
        criteria.constraint.push(new Constraint(constraint.verb + constraint.verb_suffix, constraint.field, constraint.value));
      });
      selectionCriteria.criteria.push(criteria);
    })
    return selectionCriteria;
  }
  
  public updatePage(event) {
    this.page = event.value;
    HelperFunctions.scroll();
  }
}