import {NgModule,Component,ElementRef,Input,Output,EventEmitter,AfterContentInit,ContentChildren,QueryList,TemplateRef,IterableDiffers,forwardRef,ViewChild} from '@angular/core';
import {CommonModule} from '@angular/common';
import {SharedModule,PrimeTemplate} from '../common/shared';
import {InputTextModule} from '../inputtext/inputtext';
import {DomHandler} from '../dom/domhandler';
import {NG_VALUE_ACCESSOR, ControlValueAccessor} from '@angular/forms';

export const CHIPS_VALUE_ACCESSOR: any = {
  provide: NG_VALUE_ACCESSOR,
  useExisting: forwardRef(() => Chips),
  multi: true
};

@Component({
    selector: 'p-chips',
    template: `
        <div [ngClass]="'ui-chips ui-widget'" [ngStyle]="style" [class]="styleClass" (click)="onClick($event)">
            <ul [ngClass]="{'ui-inputtext ui-state-default ui-corner-all':true,'ui-state-focus':focus,'ui-state-disabled':disabled}">
                <li #token *ngFor="let item of value; let i = index;" class="ui-chips-token ui-state-highlight ui-corner-all">
                    <span *ngIf="!disabled" class="ui-chips-token-icon fa fa-fw fa-close" (click)="removeItem($event,i)"></span>
                    <span *ngIf="!itemTemplate" class="ui-chips-token-label">{{field ? resolveFieldData(item,field) : item}}</span>
                    <ng-container *ngTemplateOutlet="itemTemplate; context: {$implicit: item}"></ng-container>
                </li>
                <li class="ui-chips-input-token">
                    <input #inputtext type="text" [attr.id]="inputId" [attr.placeholder]="(value && value.length ? null : placeholder)" [attr.tabindex]="tabindex" (keydown)="onKeydown($event)" 
                        (focus)="onInputFocus($event)" (blur)="onInputBlur($event)" [disabled]="disabled" [ngStyle]="inputStyle" [class]="inputStyleClass">
                </li>
            </ul>
        </div>
    `,
    providers: [DomHandler,CHIPS_VALUE_ACCESSOR]
})
export class Chips implements AfterContentInit,ControlValueAccessor {

    @Input() style: any;

    @Input() styleClass: string;
    
    @Input() disabled: boolean;

    @Output() onAdd: EventEmitter<any> = new EventEmitter();
    
    @Output() onRemove: EventEmitter<any> = new EventEmitter();
    
    @Input() field: string;
    
    @Input() placeholder: string;
    
    @Input() max: number;

    @Input() tabindex: number;

    @Input() inputId: string;
    
    @Input() allowDuplicate: boolean = true;
    
    @Input() inputStyle: any;
    
    @Input() inputStyleClass: any;
    
    @Input() addOnTab: boolean;

    @Input() addOnBlur: boolean;

    @Output() onFocus: EventEmitter<any> = new EventEmitter();
    
    @Output() onBlur: EventEmitter<any> = new EventEmitter();

    @ViewChild('inputtext') inputViewChild: ElementRef;
    
    @ContentChildren(PrimeTemplate) templates: QueryList<any>;
    
    public itemTemplate: TemplateRef<any>;
        
    value: any;
    
    onModelChange: Function = () => {};
    
    onModelTouched: Function = () => {};
        
    valueChanged: boolean;
    
    focus: boolean;
            
    constructor(public el: ElementRef, public domHandler: DomHandler) {}
    
    ngAfterContentInit() {
        this.templates.forEach((item) => {
            switch(item.getType()) {
                case 'item':
                    this.itemTemplate = item.template;
                break;
                
                default:
                    this.itemTemplate = item.template;
                break;
            }
        });
    }
    
    onClick(event) {
        this.inputViewChild.nativeElement.focus();
    }

    writeValue(value: any) : void {
        this.value = value;
        this.updateMaxedOut();
    }
    
    registerOnChange(fn: Function): void {
        this.onModelChange = fn;
    }

    registerOnTouched(fn: Function): void {
        this.onModelTouched = fn;
    }
    
    setDisabledState(val: boolean): void {
        this.disabled = val;
    }
    
    resolveFieldData(data: any, field: string): any {
        if(data && field) {
            if(field.indexOf('.') == -1) {
                return data[field];
            }
            else {
                let fields: string[] = field.split('.');
                let value = data;
                for(var i = 0, len = fields.length; i < len; ++i) {
                    value = value[fields[i]];
                }
                return value;
            }
        }
        else {
            return null;
        }
    }
    
    onInputFocus(event: FocusEvent) {
        this.focus = true;
        this.onFocus.emit(event);
    }

    onInputBlur(event: FocusEvent) {
        this.focus = false;
        if(this.addOnBlur && this.inputViewChild.nativeElement.value) {
            this.addItem(event, this.inputViewChild.nativeElement.value);
            this.inputViewChild.nativeElement.value = '';
        }
        this.onModelTouched();
        this.onBlur.emit(event);
    }
    
    removeItem(event: Event, index: number): void {
        if(this.disabled) {
            return;
        }
        
        let removedItem = this.value[index];
        this.value = this.value.filter((val, i) => i!=index);
        this.onModelChange(this.value);
        this.onRemove.emit({
            originalEvent: event,
            value: removedItem
        });
        this.updateMaxedOut();
    }
    
    addItem(event: Event, item: string): void {
        this.value = this.value||[];
        if(item && item.trim().length) {
            if(this.allowDuplicate || this.value.indexOf(item) === -1) {
                this.value = [...this.value, item];
                this.onModelChange(this.value);
                this.onAdd.emit({
                    originalEvent: event,
                    value: item
                });
            }
        }
        this.updateMaxedOut();
    }
    
    onKeydown(event: KeyboardEvent): void {
        switch(event.which) {
            //backspace
            case 8:
                if(this.inputViewChild.nativeElement.value.length === 0 && this.value && this.value.length > 0) {
                    this.value = [...this.value];
                    let removedItem = this.value.pop();
                    this.onModelChange(this.value);
                    this.onRemove.emit({
                        originalEvent: event,
                        value: removedItem
                    });
                }
            break;
            
            //enter
            case 13:
                this.addItem(event, this.inputViewChild.nativeElement.value);
                this.inputViewChild.nativeElement.value = '';
                
                event.preventDefault();
            break;
            
            case 9:
                if(this.addOnTab && this.inputViewChild.nativeElement.value !== '') {
                    this.addItem(event, this.inputViewChild.nativeElement.value);
                    this.inputViewChild.nativeElement.value = '';

                    event.preventDefault();
                }
            break;
            
            default:
                if(this.max && this.value && this.max === this.value.length) {
                    event.preventDefault();
                }
            break;
        }
    }
    
    updateMaxedOut() {
        if(this.inputViewChild && this.inputViewChild.nativeElement) {
            if(this.max && this.value && this.max === this.value.length)
                this.inputViewChild.nativeElement.disabled = true;
            else
            this.inputViewChild.nativeElement.disabled = false;
        }
    }
}

@NgModule({
    imports: [CommonModule,InputTextModule,SharedModule],
    exports: [Chips,InputTextModule,SharedModule],
    declarations: [Chips]
})
export class ChipsModule { }