//----------------------------------------------------------------
// Copyright (c) Microsoft Corporation.  All rights reserved.
//----------------------------------------------------------------
 
namespace System.Activities.Expressions
{
    using System.Activities;
    using System.Activities.DynamicUpdate;
    using System.Activities.Statements;
    using System.ComponentModel;
    using System.Diagnostics.CodeAnalysis;
    using System.Runtime;
 
    [SuppressMessage(FxCop.Category.Naming, FxCop.Rule.IdentifiersShouldNotMatchKeywords, Justification = "Optimizing for XAML naming. VB imperative users will [] qualify (e.g. New [AndAlso])")]
    public sealed class AndAlso : Activity<bool>
    {
        public AndAlso()
            : base()
        {
           this.Implementation =
               () => 
               {
                   if (this.Left != null && this.Right != null)
                   {
                       return new If
                       {
                           Condition = this.Left,
                           Then = new Assign<bool>
                           {
                               To = new OutArgument<bool>(context => this.Result.Get(context)),
                               Value = new InArgument<bool>(this.Right)
                           },
                           Else = new Assign<bool>
                           {
                               To = new OutArgument<bool>(context => this.Result.Get(context)),
                               Value = false,
                           }
                       };
                   }
                   else
                   {
                       return null;
                   }
               };
        }
 
        [DefaultValue(null)]
        public Activity<bool> Left
        {
            get;
            set;
        }
 
        [DefaultValue(null)]
        public Activity<bool> Right
        {
            get;
            set;
        }
 
        protected override void OnCreateDynamicUpdateMap(UpdateMapMetadata metadata, Activity originalActivity)
        {
            metadata.AllowUpdateInsideThisActivity();
        }
 
        protected override void CacheMetadata(ActivityMetadata metadata)
        {
            metadata.AddImportedChild(this.Left);
            metadata.AddImportedChild(this.Right);
 
            if (this.Left == null)
            {
                metadata.AddValidationError(SR.BinaryExpressionActivityRequiresArgument("Left", "AndAlso", this.DisplayName));
            }
 
            if (this.Right == null)
            {
                metadata.AddValidationError(SR.BinaryExpressionActivityRequiresArgument("Right", "AndAlso", this.DisplayName));
            }
        }
    }
}