import { LocaleService } from '@farris/ui-locale';
import { Injectable, ApplicationRef, ComponentFactoryResolver, Injector, ComponentRef, ElementRef } from '@angular/core';
import { LoadingConfig, LOADING_DEFAULT_CONFIG, loaddingDefaultConfig } from './loading.config';
import { LoadingComponent } from './loading.component';
import { max } from 'lodash-es';

@Injectable()
export class LoadingService {
    config: LoadingConfig;

    private currentLoadingInstanceID = null;
    private loadingInstances: { [key: number]: ComponentRef<LoadingComponent> } = {};
    private localeSer: LocaleService;
    constructor(private appRef: ApplicationRef,
                private cfr: ComponentFactoryResolver, private injecotr: Injector) {
                    this.localeSer = this.injecotr.get(LocaleService);
    }

    show(config?: LoadingConfig): LoadingComponent {
        this.config = this.injecotr.get(LOADING_DEFAULT_CONFIG) || {};
        this.config = Object.assign(loaddingDefaultConfig, this.config);

        let _loadingCmpRef: ComponentRef<LoadingComponent>;
        const loadingFactory = this.cfr.resolveComponentFactory(LoadingComponent);
        _loadingCmpRef = loadingFactory.create(this.injecotr);

        if (config) {
            this.config = Object.assign({}, this.config, config);
        }
        const languageCode = localStorage.getItem('languageCode');
        // if (languageCode === 'en') {
        //     this.config.message = 'Loading...';
        // }
        if (this.localeSer) {
            if (!this.config.message || this.config.message === '正在加载中，请稍候...') {
                this.config.message = this.localeSer.getValue('loading.message');
            }
        }

        const container = this.config.container;
        if (container === 'body') {
            document.querySelector(container as string).appendChild( _loadingCmpRef.location.nativeElement);
        } else {
            if (container instanceof ElementRef ) {
                container.nativeElement.appendChild(
                    _loadingCmpRef.location.nativeElement
                );
            } else {
                if (container instanceof Element) {
                    container.appendChild(
                        _loadingCmpRef.location.nativeElement
                    );
                }
            }
        }
        _loadingCmpRef.instance.delay = this.config.delay;
        _loadingCmpRef.instance.isActive = true;
        Object.assign(_loadingCmpRef.instance, this.config);

        _loadingCmpRef.instance.closed.subscribe(state => {
            if (!state) {
                delete this.loadingInstances[_loadingCmpRef.instance.id];
                this.currentLoadingInstanceID = this.getMaxLoadingID();
                this.clearDom(_loadingCmpRef);
            }
        });

        _loadingCmpRef.changeDetectorRef.markForCheck();
        _loadingCmpRef.changeDetectorRef.detectChanges();

        const loadingID = this.createInsId();
        _loadingCmpRef.instance.id = loadingID;
        this.loadingInstances[loadingID] =  _loadingCmpRef;
        this.currentLoadingInstanceID = loadingID;

        return _loadingCmpRef.instance;
    }

    close(loadingId?: number) {
        const id = loadingId || this.currentLoadingInstanceID;
        const loadingRef = this.loadingInstances[id];
        if (loadingRef) {
            loadingRef.instance.close();
        }
    }

    clearAll() {
        const keys = Object.keys(this.loadingInstances);
        if (keys.length) {
            keys.forEach(id => {
                this.clearDom(this.loadingInstances[id]);
            });
        } else {
            const loadings = document.querySelectorAll('farris-loading');
            if (loadings.length) {
                loadings.forEach( el => el.remove() );
            }

            this.loadingInstances = {};
        }
    }

    private clearDom(_loadingCmpRef: ComponentRef<LoadingComponent>) {
        if (_loadingCmpRef && _loadingCmpRef.location) {
            const loadingEl = _loadingCmpRef.location.nativeElement;

            if (loadingEl.parentNode) {
                loadingEl.parentNode.removeChild(loadingEl);
            }

            _loadingCmpRef.destroy();
        }

        _loadingCmpRef = null;
    }

    private createInsId() {
        return this.getMaxLoadingID() + 1;
    }

    private getMaxLoadingID() {
        const ids = Object.keys(this.loadingInstances).map(k => parseInt(k, 10));
        if (ids.length) {
            return max(ids);
        }

        return 0;
    }
}