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//----------------------------------------------------------------
// Copyright (c) Microsoft Corporation. All rights reserved.
//----------------------------------------------------------------
namespace System.Activities.Statements
{
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Runtime;
using System.Activities.Validation;
using System.Linq;
using System.Activities.Expressions;
public sealed class Compensate : NativeActivity
{
static Constraint compensateWithNoTarget = Compensate.CompensateWithNoTarget();
InternalCompensate internalCompensate;
DefaultCompensation defaultCompensation;
Variable<CompensationToken> currentCompensationToken;
public Compensate()
: base()
{
this.currentCompensationToken = new Variable<CompensationToken>();
}
[DefaultValue(null)]
public InArgument<CompensationToken> Target
{
get;
set;
}
DefaultCompensation DefaultCompensation
{
get
{
if (this.defaultCompensation == null)
{
this.defaultCompensation = new DefaultCompensation()
{
Target = new InArgument<CompensationToken>(this.currentCompensationToken),
};
}
return this.defaultCompensation;
}
}
InternalCompensate InternalCompensate
{
get
{
if (this.internalCompensate == null)
{
this.internalCompensate = new InternalCompensate()
{
Target = new InArgument<CompensationToken>(new ArgumentValue<CompensationToken> { ArgumentName = "Target" }),
};
}
return this.internalCompensate;
}
}
protected override void CacheMetadata(NativeActivityMetadata metadata)
{
RuntimeArgument targetArgument = new RuntimeArgument("Target", typeof(CompensationToken), ArgumentDirection.In);
metadata.Bind(this.Target, targetArgument);
metadata.SetArgumentsCollection(new Collection<RuntimeArgument> { targetArgument });
metadata.SetImplementationVariablesCollection(new Collection<Variable> { this.currentCompensationToken });
Fx.Assert(DefaultCompensation != null, "DefaultCompensation must be valid");
Fx.Assert(InternalCompensate != null, "InternalCompensate must be valid");
metadata.SetImplementationChildrenCollection(
new Collection<Activity>
{
DefaultCompensation,
InternalCompensate
});
}
internal override IList<Constraint> InternalGetConstraints()
{
return new List<Constraint>(1) { compensateWithNoTarget };
}
static Constraint CompensateWithNoTarget()
{
DelegateInArgument<Compensate> element = new DelegateInArgument<Compensate> { Name = "element" };
DelegateInArgument<ValidationContext> validationContext = new DelegateInArgument<ValidationContext> { Name = "validationContext" };
Variable<bool> assertFlag = new Variable<bool> { Name = "assertFlag" };
Variable<IEnumerable<Activity>> elements = new Variable<IEnumerable<Activity>>() { Name = "elements" };
Variable<int> index = new Variable<int>() { Name = "index" };
return new Constraint<Compensate>
{
Body = new ActivityAction<Compensate, ValidationContext>
{
Argument1 = element,
Argument2 = validationContext,
Handler = new Sequence
{
Variables =
{
assertFlag,
elements,
index
},
Activities =
{
new If
{
Condition = new InArgument<bool>((env) => element.Get(env).Target != null),
Then = new Assign<bool>
{
To = assertFlag,
Value = true
},
Else = new Sequence
{
Activities =
{
new Assign<IEnumerable<Activity>>
{
To = elements,
Value = new GetParentChain
{
ValidationContext = validationContext,
},
},
new While(env => (assertFlag.Get(env) != true) && index.Get(env) < elements.Get(env).Count())
{
Body = new Sequence
{
Activities =
{
new If(env => (elements.Get(env).ElementAt(index.Get(env))).GetType() == typeof(CompensationParticipant))
{
Then = new Assign<bool>
{
To = assertFlag,
Value = true
},
},
new Assign<int>
{
To = index,
Value = new InArgument<int>(env => index.Get(env) + 1)
},
}
}
}
}
}
},
new AssertValidation
{
Assertion = new InArgument<bool>(assertFlag),
Message = new InArgument<string>(SR.CompensateWithNoTargetConstraint)
}
}
}
}
};
}
protected override void Execute(NativeActivityContext context)
{
CompensationExtension compensationExtension = context.GetExtension<CompensationExtension>();
if (compensationExtension == null)
{
throw FxTrace.Exception.AsError(new InvalidOperationException(SR.CompensateWithoutCompensableActivity(this.DisplayName)));
}
if (Target.IsEmpty)
{
CompensationToken ambientCompensationToken = (CompensationToken)context.Properties.Find(CompensationToken.PropertyName);
CompensationTokenData ambientTokenData = ambientCompensationToken == null ? null : compensationExtension.Get(ambientCompensationToken.CompensationId);
if (ambientTokenData != null && ambientTokenData.IsTokenValidInSecondaryRoot)
{
this.currentCompensationToken.Set(context, ambientCompensationToken);
if (ambientTokenData.ExecutionTracker.Count > 0)
{
context.ScheduleActivity(DefaultCompensation);
}
}
else
{
throw FxTrace.Exception.AsError(new InvalidOperationException(SR.InvalidCompensateActivityUsage(this.DisplayName)));
}
}
else
{
CompensationToken compensationToken = Target.Get(context);
CompensationTokenData tokenData = compensationToken == null ? null : compensationExtension.Get(compensationToken.CompensationId);
if (compensationToken == null)
{
throw FxTrace.Exception.Argument("Target", SR.InvalidCompensationToken(this.DisplayName));
}
if (compensationToken.CompensateCalled)
{
// No-Op
return;
}
if (tokenData == null || tokenData.CompensationState != CompensationState.Completed)
{
throw FxTrace.Exception.AsError(new InvalidOperationException(SR.CompensableActivityAlreadyConfirmedOrCompensated));
}
// A valid in-arg was passed...
tokenData.CompensationState = CompensationState.Compensating;
compensationToken.CompensateCalled = true;
context.ScheduleActivity(InternalCompensate);
}
}
protected override void Cancel(NativeActivityContext context)
{
// Suppress Cancel
}
}
}
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