/*!
 * @license
 * Copyright 2019 Alfresco Software, Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { SearchService } from '@alfresco/adf-core';
import {
    AfterContentInit,
    Component,
    ContentChild,
    ElementRef,
    EventEmitter,
    Input,
    OnChanges,
    Output,
    TemplateRef,
    ViewChild,
    ViewEncapsulation,
    OnDestroy
} from '@angular/core';
import { NodePaging } from '@alfresco/js-api';
import { Subject } from 'rxjs';
import { debounceTime, takeUntil } from 'rxjs/operators';

@Component({
    selector: 'adf-search',
    templateUrl: './search.component.html',
    styleUrls: ['./search.component.scss'],
    encapsulation: ViewEncapsulation.None,
    preserveWhitespaces: false,
    exportAs: 'searchAutocomplete',
    host: {
        'class': 'adf-search'
    }
})
export class SearchComponent implements AfterContentInit, OnChanges, OnDestroy {

    @ViewChild('panel')
    panel: ElementRef;

    @ContentChild(TemplateRef)
    template: TemplateRef<any>;

    /** Function that maps an option's value to its display value in the trigger. */
    @Input()
    displayWith: ((value: any) => string) | null = null;

    /** Maximum number of results to show in the search. */
    @Input()
    maxResults: number = 20;

    /** Number of results to skip from the results pagination. */
    @Input()
    skipResults: number = 0;

    /** Search term to use when executing the search. Updating this value will
     * run a new search and update the results.
     */
    @Input()
    searchTerm: string = '';

    /** CSS class for display. */
    @Input('class')
    set classList(classList: string) {
        if (classList && classList.length) {
            classList.split(' ').forEach((className) => this._classList[className.trim()] = true);
            this._elementRef.nativeElement.className = '';
        }
    }

    /** Emitted when search results have fully loaded. */
    @Output()
    resultLoaded: EventEmitter<NodePaging> = new EventEmitter();

    /** Emitted when an error occurs. */
    @Output()
    error: EventEmitter<any> = new EventEmitter();

    showPanel: boolean = false;
    results: NodePaging;

    get isOpen(): boolean {
        return this._isOpen && this.showPanel;
    }

    set isOpen(value: boolean) {
        this._isOpen = value;
    }

    _isOpen: boolean = false;
    keyPressedStream = new Subject<string>();
    _classList: { [key: string]: boolean } = {};
    private onDestroy$ = new Subject<boolean>();

    constructor(private searchService: SearchService,
                private _elementRef: ElementRef) {
        this.keyPressedStream
            .pipe(
                debounceTime(200),
                takeUntil(this.onDestroy$)
            )
            .subscribe(searchedWord => {
                this.loadSearchResults(searchedWord);
            });

        searchService.dataLoaded
            .pipe(takeUntil(this.onDestroy$))
            .subscribe(
                nodePaging => this.onSearchDataLoaded(nodePaging),
                error => this.onSearchDataError(error)
            );
    }

    ngAfterContentInit() {
        this.setVisibility();
    }

    ngOnChanges(changes) {
        if (changes.searchTerm && changes.searchTerm.currentValue) {
            this.loadSearchResults(changes.searchTerm.currentValue);
        }
    }

    ngOnDestroy() {
        this.onDestroy$.next(true);
        this.onDestroy$.complete();
    }

    resetResults() {
        this.cleanResults();
        this.setVisibility();
    }

    reload() {
        this.loadSearchResults(this.searchTerm);
    }

    private cleanResults() {
        if (this.results) {
            this.results = {};
        }
    }

    private loadSearchResults(searchTerm?: string) {
        this.resetResults();
        if (searchTerm) {
            this.searchService.search(searchTerm, this.maxResults, this.skipResults).subscribe(
                (result) => this.onSearchDataLoaded(result),
                (err) => this.onSearchDataError(err)
            );
        } else {
            this.cleanResults();
        }
    }

    onSearchDataLoaded(nodePaging: NodePaging) {
        if (nodePaging) {
            this.results = nodePaging;
            this.resultLoaded.emit(this.results);
            this.isOpen = true;
            this.setVisibility();
        }
    }

    onSearchDataError(error) {
        if (error && error.status !== 400) {
            this.results = null;
            this.error.emit(error);
        }
    }

    hidePanel() {
        if (this.isOpen) {
            this._classList['adf-search-show'] = false;
            this._classList['adf-search-hide'] = true;
            this.isOpen = false;
        }
    }

    setVisibility() {
        this.showPanel = !!this.results && !!this.results.list;
        this._classList['adf-search-show'] = this.showPanel;
        this._classList['adf-search-hide'] = !this.showPanel;
    }
}