import { Observable, of, BehaviorSubject } from 'rxjs';
import { switchMap } from 'rxjs/operators';
import { FavoriteAction } from '../lookup-displaytype';
import { LookupGridComponent } from '../lookup-grid.component';

export interface SelectionState {
    selecteditems: any[];
    favoriteItems: any[];
    quickItems: any[];
}

export class LookupSelectionService {

    private state: SelectionState = {
        selecteditems: [],
        favoriteItems: [],
        quickItems: []
    };

    state$: BehaviorSubject<SelectionState> = new BehaviorSubject(this.state);

    selected$: Observable<any[]> = this.state$.pipe(
        switchMap(n => of(n.selecteditems))
    );

    favoriteItems$: BehaviorSubject<any> = new BehaviorSubject({items: this.state.favoriteItems, action: null });

    quickItems$: Observable<any[]> = this.state$.pipe(
        switchMap(n => of(n.quickItems))
    );

    private get idField() {
        return this.ins.idField;
    }

    constructor(private ins: LookupGridComponent) {
    }

    initFavoriteItems(items: any[]) {
        this.state.favoriteItems = items || [];
    }


    //#region 收藏数据

    updateFavoriteData(data: any, action: FavoriteAction) {

        if (this.ins.savingFaoriteData) {
            // console.log('%c太调皮了吧！', 'color: white');
            return;
        }

        if (action === FavoriteAction.add) {
            this.state.favoriteItems = this.state.favoriteItems.concat([data]);
        } else {
            this.state.favoriteItems = this.state.favoriteItems.filter(n => n[this.idField] !== data[this.idField]);
        }

        this.favoriteItems$.next({ items: this.state.favoriteItems, action });
    }

    //#endregion

    //#region 多选数据

    loadSelections( data: []) {
        this.state.selecteditems = [...data];
        this.state$.next(this.state);
    }

    getSelections() {
        return [...this.state.selecteditems];
    }

    select(item: any) {
        if (item) {
            this.state.selecteditems = [...this.state.selecteditems, item];
            this.state$.next(this.state);
        }
    }

    unselectByPathcode(pathcode: string) {
        const { dataField, pathField } = this.ins.treeInfo;
        this.state.selecteditems = this.state.selecteditems.filter(n => {
            return n[dataField][pathField] && n[dataField][pathField].indexOf(pathcode) !== 0;
        });
    }

    updateSelections(data: any, checked = true) {

        if (!Array.isArray(data)) {
            data = [data];
        }

        const items = [ ...data ];
        const idField = this.idField;
        if (checked) {
            if (this.state.selecteditems && !this.state.selecteditems.length) {
                this.state.selecteditems = items;
            } else {
                const ids = items.map(n => n[idField]);
                ids.forEach((n, i) => {
                    if (!this.state.selecteditems.find(r => r[idField] == n)) {
                        this.state.selecteditems.push(items[i]);
                    }
                });
            }
        } else {
            if (data) {
                const ids2 = data.map(n => n[idField]);
                this.state.selecteditems = this.state.selecteditems.filter(n => {
                    return ids2.indexOf(n[idField]) === -1;
                });
            }
        }

        this.state$.next(this.state);
    }

    unSelect(id: any) {
        if (id) {
            if (Array.isArray(id)) {
                this.state.selecteditems = this.state.selecteditems.filter(n => {
                    return id.indexOf(n[this.idField]) === -1;
                });
            } else {
                this.state.selecteditems = this.state.selecteditems.filter(n => n[this.idField] != id);
            }

            this.state$.next(this.state);
        }
    }

    clearSelections() {
        this.state.selecteditems = [];
        this.state$.next(this.state);
    }

    //#endregion

}