import { AfterViewInit, Component, Input, OnChanges, OnInit, SimpleChanges, ViewChild, Output, EventEmitter } from '@angular/core';
import { AbstractControl, AbstractControlOptions, FormArray, FormGroup } from '@angular/forms';
import { MatExpansionPanel } from '@angular/material';
import { MatHorizontalStepper } from '@angular/material/stepper';
import { Rule } from '@app/core/model/dataset-profile-definition/rule';
import { DatasetProfileTableOfContentsInternalSection } from '@app/ui/admin/dataset-profile/table-of-contents/table-of-contents-internal-section/table-of-contents-internal-section';
import { LinkToScroll } from '@app/ui/misc/dataset-description-form/tableOfContentsMaterial/table-of-contents';
import { VisibilityRulesService } from '@app/ui/misc/dataset-description-form/visibility-rules/visibility-rules.service';
import { BaseComponent } from '@common/base/base.component';
import { takeUntil } from 'rxjs/operators';

@Component({
	selector: 'app-dataset-description',
	templateUrl: './dataset-description.component.html',
	styleUrls: ['./dataset-description.component.scss']
})
export class DatasetDescriptionComponent extends BaseComponent implements OnInit, AfterViewInit, OnChanges {

	// @ViewChild('stepper', { static: false }) stepper: MatHorizontalStepper;
	@Input() path: string;
	@Input() visibilityRules: Rule[] = [];
	@Input() datasetProfileId: String;
	@Input() linkToScroll: LinkToScroll;
	@Output() formChanged: EventEmitter<any> = new EventEmitter();
	@Output() fieldsetFocusChange: EventEmitter<string> = new EventEmitter<string>();

	tocentries: ToCEntry[];
	@Input() form: FormGroup;

	@Input() TOCENTRY_ID_PREFIX="";


	private _form: FormGroup;

	constructor(
		private visibilityRulesService: VisibilityRulesService,
	) {
		super();
		
	}

	ngOnInit() {
		this.visibilityRulesService.buildVisibilityRules(this.visibilityRules, this.form);
		// if (this.form) {
		// 	this.form.valueChanges
		// 		.pipe(takeUntil(this._destroyed))
		// 		.subscribe(val => {
		// 			this.formChanged.emit(val);
		// 		});
		// }
		
		this.tocentries = this.getTocEntries();
	}

	ngOnChanges(changes: SimpleChanges) {

		// When the form is changed set stepper index to 0.
		// if (this.stepper && changes['form'] && !changes['form'].isFirstChange()) {
		// 	this.stepper.selectedIndex = 0;
		// } else if (this.stepper && changes['linkToScroll'] && changes['linkToScroll'].currentValue) {
		// 	if (changes['linkToScroll'].currentValue.page >= 0) {
		// 		this.stepper.selectedIndex = changes['linkToScroll'].currentValue.page;
		// 	}
		// }
	}

	ngAfterViewInit() {

	}



	onAskedToScroll(panel: MatExpansionPanel, id?:string){
		panel.open();
		this.fieldsetFocusChange.emit(id);
	}




	private _buildRecursively(form: FormGroup,whatAmI:ToCEntryType):ToCEntry{
		if(!form) return null;

		switch(whatAmI){
			case ToCEntryType.Section:
				const sections = form.get('sections') as FormArray;
				const fieldsets = form.get('compositeFields') as FormArray;


				const tempResult:ToCEntry[] = [];
				
				if(sections &&sections.length){
					sections.controls.forEach(section=>{
						tempResult.push(this._buildRecursively(section as FormGroup, ToCEntryType.Section));
					});

				}else if(fieldsets && fieldsets.length){
					fieldsets.controls.forEach(fieldset=>{
						tempResult.push(this._buildRecursively(fieldset as FormGroup, ToCEntryType.FieldSet));
					});
				}
				return {
					form: form,
					id: form.get('id').value,
					label: form.get('title').value,
					numbering: '',
					subEntries:tempResult,
					subEntriesType: sections &&sections.length? ToCEntryType.Section: ToCEntryType.FieldSet,
					type: ToCEntryType.Section,
					ordinal: form.get('ordinal').value
				}
			case ToCEntryType.FieldSet:
				return {
					form: form,
					label:form.get('title').value,
					id: form.get('id').value,
					numbering:'s',
					subEntries:[],
					subEntriesType: ToCEntryType.Field,
					type: ToCEntryType.FieldSet,
					ordinal: form.get('ordinal').value
				}
		}
	}

	private _sortByOrdinal(tocentries: ToCEntry[]){
		
		if(!tocentries || !tocentries.length) return;
		
		tocentries.sort(this._customCompare);
		tocentries.forEach(entry=>{
			this._sortByOrdinal(entry.subEntries);
		});
	}

	private _customCompare(a,b){
		return a.ordinal - b.ordinal;
	}

	private _calculateNumbering(tocentries: ToCEntry[], depth:number[] = []){
		if(!tocentries || !tocentries.length){
			return;
		}

		let  prefixNumbering = depth.length? depth.join('.'): '';

		if(depth.length) prefixNumbering = prefixNumbering+".";
		tocentries.forEach((entry,i)=>{
			entry.numbering = prefixNumbering + (i+1);
			this._calculateNumbering(entry.subEntries, [...depth, i+1])
		});
	}

	
	getTocEntries(): ToCEntry[] {
		if (this.form == null) { return []; }
		const result: ToCEntry[] = [];

		//build parent pages
		(this.form.get('pages') as FormArray).controls.forEach((pageElement, i) => {
			result.push({
				id: i+'id',
				label: pageElement.get('title').value,
				type: ToCEntryType.Page,
				form: pageElement,
				numbering: (i + 1).toString(),
				subEntriesType: ToCEntryType.Section,
				subEntries:[],
				ordinal: pageElement.get('ordinal').value
			} as ToCEntry)
		});



		result.forEach((entry,i)=>{

			const sections = entry.form.get('sections') as FormArray;

			sections.controls.forEach(section=>{
				const tempResults = this._buildRecursively(section as FormGroup,ToCEntryType.Section);
				entry.subEntries.push(tempResults);
			});

		});

		this._sortByOrdinal(result);
		//calculate numbering
		this._calculateNumbering(result);
		return result;

	}

}
export interface ToCEntry {
	id: string;
	label: string;
	subEntriesType: ToCEntryType;
	subEntries: ToCEntry[];
	type: ToCEntryType;
	form: AbstractControl;
	numbering: string;
	ordinal: number;
}
export enum ToCEntryType {
	Page = 0,
	Section = 1,
	FieldSet = 2,
	Field = 3
}