var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) {
    var c = arguments.length, r = c < 3 ? target : desc === null ? desc = Object.getOwnPropertyDescriptor(target, key) : desc, d;
    if (typeof Reflect === "object" && typeof Reflect.decorate === "function") r = Reflect.decorate(decorators, target, key, desc);
    else for (var i = decorators.length - 1; i >= 0; i--) if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r;
    return c > 3 && r && Object.defineProperty(target, key, r), r;
};
var __metadata = (this && this.__metadata) || function (k, v) {
    if (typeof Reflect === "object" && typeof Reflect.metadata === "function") return Reflect.metadata(k, v);
};
var __param = (this && this.__param) || function (paramIndex, decorator) {
    return function (target, key) { decorator(target, key, paramIndex); }
};
import { Directive, Host, ViewContainerRef, TemplateRef } from 'angular2/core';
import { isPresent, isBlank, normalizeBlank, CONST_EXPR } from 'angular2/src/facade/lang';
import { ListWrapper, Map } from 'angular2/src/facade/collection';
const _WHEN_DEFAULT = CONST_EXPR(new Object());
class SwitchView {
    constructor(_viewContainerRef, _templateRef) {
        this._viewContainerRef = _viewContainerRef;
        this._templateRef = _templateRef;
    }
    create() { this._viewContainerRef.createEmbeddedView(this._templateRef); }
    destroy() { this._viewContainerRef.clear(); }
}
/**
 * Adds or removes DOM sub-trees when their match expressions match the switch expression.
 *
 * Elements within `NgSwitch` but without `NgSwitchWhen` or `NgSwitchDefault` directives will be
 * preserved at the location as specified in the template.
 *
 * `NgSwitch` simply inserts nested elements based on which match expression matches the value
 * obtained from the evaluated switch expression. In other words, you define a container element
 * (where you place the directive with a switch expression on the
 * **`[ng-switch]="..."` attribute**), define any inner elements inside of the directive and
 * place a `[ng-switch-when]` attribute per element.
 *
 * The `ng-switch-when` property is used to inform `NgSwitch` which element to display when the
 * expression is evaluated. If a matching expression is not found via a `ng-switch-when` property
 * then an element with the `ng-switch-default` attribute is displayed.
 *
 * ### Example ([live demo](http://plnkr.co/edit/DQMTII95CbuqWrl3lYAs?p=preview))
 *
 * ```typescript
 * @Component({selector: 'app'})
 * @View({
 *   template: `
 *     <p>Value = {{value}}</p>
 *     <button (click)="inc()">Increment</button>
 *
 *     <div [ng-switch]="value">
 *       <p *ng-switch-when="'init'">increment to start</p>
 *       <p *ng-switch-when="0">0, increment again</p>
 *       <p *ng-switch-when="1">1, increment again</p>
 *       <p *ng-switch-when="2">2, stop incrementing</p>
 *       <p *ng-switch-default>&gt; 2, STOP!</p>
 *     </div>
 *
 *     <!-- alternate syntax -->
 *
 *     <p [ng-switch]="value">
 *       <template ng-switch-when="init">increment to start</template>
 *       <template [ng-switch-when]="0">0, increment again</template>
 *       <template [ng-switch-when]="1">1, increment again</template>
 *       <template [ng-switch-when]="2">2, stop incrementing</template>
 *       <template ng-switch-default>&gt; 2, STOP!</template>
 *     </p>
 *   `,
 *   directives: [NgSwitch, NgSwitchWhen, NgSwitchDefault]
 * })
 * export class App {
 *   value = 'init';
 *
 *   inc() {
 *     this.value = this.value === 'init' ? 0 : this.value + 1;
 *   }
 * }
 *
 * bootstrap(App).catch(err => console.error(err));
 * ```
 */
export let NgSwitch = class {
    constructor() {
        this._useDefault = false;
        this._valueViews = new Map();
        this._activeViews = [];
    }
    set ngSwitch(value) {
        // Empty the currently active ViewContainers
        this._emptyAllActiveViews();
        // Add the ViewContainers matching the value (with a fallback to default)
        this._useDefault = false;
        var views = this._valueViews.get(value);
        if (isBlank(views)) {
            this._useDefault = true;
            views = normalizeBlank(this._valueViews.get(_WHEN_DEFAULT));
        }
        this._activateViews(views);
        this._switchValue = value;
    }
    /** @internal */
    _onWhenValueChanged(oldWhen, newWhen, view) {
        this._deregisterView(oldWhen, view);
        this._registerView(newWhen, view);
        if (oldWhen === this._switchValue) {
            view.destroy();
            ListWrapper.remove(this._activeViews, view);
        }
        else if (newWhen === this._switchValue) {
            if (this._useDefault) {
                this._useDefault = false;
                this._emptyAllActiveViews();
            }
            view.create();
            this._activeViews.push(view);
        }
        // Switch to default when there is no more active ViewContainers
        if (this._activeViews.length === 0 && !this._useDefault) {
            this._useDefault = true;
            this._activateViews(this._valueViews.get(_WHEN_DEFAULT));
        }
    }
    /** @internal */
    _emptyAllActiveViews() {
        var activeContainers = this._activeViews;
        for (var i = 0; i < activeContainers.length; i++) {
            activeContainers[i].destroy();
        }
        this._activeViews = [];
    }
    /** @internal */
    _activateViews(views) {
        // TODO(vicb): assert(this._activeViews.length === 0);
        if (isPresent(views)) {
            for (var i = 0; i < views.length; i++) {
                views[i].create();
            }
            this._activeViews = views;
        }
    }
    /** @internal */
    _registerView(value, view) {
        var views = this._valueViews.get(value);
        if (isBlank(views)) {
            views = [];
            this._valueViews.set(value, views);
        }
        views.push(view);
    }
    /** @internal */
    _deregisterView(value, view) {
        // `_WHEN_DEFAULT` is used a marker for non-registered whens
        if (value === _WHEN_DEFAULT)
            return;
        var views = this._valueViews.get(value);
        if (views.length == 1) {
            this._valueViews.delete(value);
        }
        else {
            ListWrapper.remove(views, view);
        }
    }
};
NgSwitch = __decorate([
    Directive({ selector: '[ng-switch]', inputs: ['ngSwitch'] }), 
    __metadata('design:paramtypes', [])
], NgSwitch);
/**
 * Insert the sub-tree when the `ng-switch-when` expression evaluates to the same value as the
 * enclosing switch expression.
 *
 * If multiple match expression match the switch expression value, all of them are displayed.
 *
 * See {@link NgSwitch} for more details and example.
 */
export let NgSwitchWhen = class {
    constructor(viewContainer, templateRef, ngSwitch) {
        // `_WHEN_DEFAULT` is used as a marker for a not yet initialized value
        /** @internal */
        this._value = _WHEN_DEFAULT;
        this._switch = ngSwitch;
        this._view = new SwitchView(viewContainer, templateRef);
    }
    set ngSwitchWhen(value) {
        this._switch._onWhenValueChanged(this._value, value, this._view);
        this._value = value;
    }
};
NgSwitchWhen = __decorate([
    Directive({ selector: '[ng-switch-when]', inputs: ['ngSwitchWhen'] }),
    __param(2, Host()), 
    __metadata('design:paramtypes', [ViewContainerRef, TemplateRef, NgSwitch])
], NgSwitchWhen);
/**
 * Default case statements are displayed when no match expression matches the switch expression
 * value.
 *
 * See {@link NgSwitch} for more details and example.
 */
export let NgSwitchDefault = class {
    constructor(viewContainer, templateRef, sswitch) {
        sswitch._registerView(_WHEN_DEFAULT, new SwitchView(viewContainer, templateRef));
    }
};
NgSwitchDefault = __decorate([
    Directive({ selector: '[ng-switch-default]' }),
    __param(2, Host()), 
    __metadata('design:paramtypes', [ViewContainerRef, TemplateRef, NgSwitch])
], NgSwitchDefault);
