// NG2
import { Component, EventEmitter, forwardRef, Input, OnInit, Output } from '@angular/core';
import { NG_VALUE_ACCESSOR, ControlValueAccessor } from '@angular/forms';
// APP
import { Helpers } from '../../../../utils/Helpers';

// Value accessor for the component (supports ngModel)
const CHECKLIST_VALUE_ACCESSOR = {
    provide: NG_VALUE_ACCESSOR,
    useExisting: forwardRef(() => NovoCheckListElement),
    multi: true
};

@Component({
    selector: 'novo-check-list',
    providers: [CHECKLIST_VALUE_ACCESSOR],
    template: `
        <div class="check-box-group" *ngFor="let option of _options; let i = index" [ngClass]="{checked: option.checked}" >
            <input [name]="name" type="checkbox" [ngModel]="option.checked" [attr.id]="name+i" [value]="option.checked" (change)="select($event, option)">
            <label [attr.for]="name+i" (click)="select($event, option)">
              <i [ngClass]="{'bhi-checkbox-empty': !option.checked, 'bhi-checkbox-filled': option.checked }"></i>
              <span>{{option.label}}</span>
            </label>
        </div>
    `
})
export class NovoCheckListElement implements ControlValueAccessor, OnInit {
    @Input() name: string;
    @Input() options: Array<any>;
    @Output() onSelect: EventEmitter<any> = new EventEmitter();

    _options: Array<any>;
    model: any;
    onModelChange: Function = () => {
    };
    onModelTouched: Function = () => {
    };

    ngOnInit() {
        this.setModel();
        this.setupOptions();
    }

    select(event, item) {
        Helpers.swallowEvent(event);
        item.checked = !item.checked;
        this.model = this._options.filter(checkBox => checkBox.checked).map(x => x.value);
        this.onModelChange(this.model.length > 0 ? this.model : '');
        this.onSelect.emit({ selected: this.model });
    }

    setupOptions() {
        this.options = this.options || [];
        this._options = [];
        if (this.options.length && !this.options[0].value) {
            this.options.forEach(option => {
                let formattedOption = {
                    value: option,
                    label: option,
                    checked: (this.model && this.model.length && (this.model.indexOf(option.value) !== -1))
                };
                this._options.push(formattedOption);
            });
        } else {
            this.options.forEach(option => {
                let formattedOption = option;
                formattedOption.checked = (this.model && this.model.length && (this.model.indexOf(option.value) !== -1));
                this._options.push(formattedOption);
            });
        }
    }

    setModel(): void {
        let checkedOptions = this.options.filter(checkBox => checkBox.checked).map(x => x.value);
        this.writeValue(checkedOptions);
    }

    writeValue(model: any): void {
        this.model = model || [];
        if (model) {
            this.setupOptions();
        }
    }

    registerOnChange(fn: Function): void {
        this.onModelChange = fn;
    }

    registerOnTouched(fn: Function): void {
        this.onModelTouched = fn;
    }
}