internal SearchExpressionContext(SearchExpressionRuntime runtime, SearchExpression expression, SearchExpression[] args, SearchExpressionExecutionFlags flags)
{
this.runtime = runtime;
this.expression = expression;
this.flags = flags;
this.args = args;
}
public SearchExpressionRuntime(SearchContext searchContext, SearchExpressionExecutionFlags flags)
{
search = searchContext;
frames = new Stack <SearchExpressionContext>();
state = new ExecutionState();
items = new Stack <SearchItem>();
frames.Push(new SearchExpressionContext(this, null, null, SearchExpressionExecutionFlags.Root | flags));
}
internal IEnumerable <SearchItem> Execute(SearchContext searchContext, SearchExpressionExecutionFlags executionFlags)
{
var runtime = new SearchExpressionRuntime(searchContext, executionFlags);
if (executionFlags.HasFlag(SearchExpressionExecutionFlags.ThreadedEvaluation))
{
return(TaskEvaluatorManager.Evaluate(runtime.current, this));
}
return(Execute(runtime.current, executionFlags));
}
internal IEnumerable <SearchItem> Execute(SearchExpressionContext c, SearchExpressionExecutionFlags executionFlags)
{
if (!evaluator.valid || evaluator.execute == null)
{
c.ThrowError("Invalid expression evaluator");
}
try
{
if (!evaluator.hints.HasFlag(SearchExpressionEvaluationHints.ThreadNotSupported))
{
return(Evaluate(c, executionFlags));
}
// We cannot only return the IEnumerable of the evaluator, as the iteration itself needs to be
// done on the main thread. If we return the IEnumerable itself, we will unroll the items and call the evaluator
// in the evaluation thread.
return(TaskEvaluatorManager.EvaluateMainThreadUnroll(() => Evaluate(c, executionFlags)));
}
catch (SearchExpressionEvaluatorException ex)
{
ExceptionDispatchInfo.Capture(ex).Throw();
return(null); // To stop visual studio complaining about not all code path return a value
}
}
public bool HasFlag(SearchExpressionExecutionFlags checkFlag)
{
return(flags.HasFlag(checkFlag));
}
public IDisposable Push(SearchExpression searchExpression, IEnumerable <SearchExpression> args, SearchExpressionExecutionFlags flags)
{
flags |= frames.Peek().flags & SearchExpressionExecutionFlags.TransferedFlags;
frames.Push(new SearchExpressionContext(this, searchExpression, args.ToArray(), flags));
return(new PushPopScope <SearchExpressionContext>(frames));
}
private IEnumerable <SearchItem> Evaluate(SearchExpressionContext c, SearchExpressionExecutionFlags flags)
{
var args = new List <SearchExpression>();
foreach (var p in parameters)
{
var evalHints = p.evaluator.hints;
if (evalHints.HasFlag(SearchExpressionEvaluationHints.AlwaysExpand) ||
(p.types.HasFlag(SearchExpressionType.Expandable) && evalHints.HasFlag(SearchExpressionEvaluationHints.ExpandSupported)))
{
foreach (var exprItem in p.Execute(c, SearchExpressionExecutionFlags.Expand))
{
if (exprItem != null)
{
if (exprItem.data is SearchExpression expr)
{
args.Add(expr);
}
else
{
c.ThrowError($"cannot expand {p}");
}
}
else
{
yield return(null);
}
}
}
else if (p.types.HasFlag(SearchExpressionType.Expandable))
{
foreach (var exprItem in p.Execute(c))
{
if (exprItem == null)
{
yield return(null);
continue;
}
if (exprItem.value != null)
{
if (Utils.TryGetNumber(exprItem.value, out var d))
{
args.Add(new SearchExpression(SearchExpressionType.Number, d.ToString().GetStringView(), Parsers.ConstantEvaluator));
}
else if (exprItem.value is string s)
{
args.Add(new SearchExpression(SearchExpressionType.Text, s.GetStringView(), Parsers.ConstantEvaluator));
}
else
{
c.ThrowError("Cannot expand parameters");
}
}
else
{
c.ThrowError("Cannot expand null value");
}
}
}
else
{
args.Add(p);
}
}
using (c.runtime.Push(this, args, flags))
{
var skipNull = c.HasFlag(SearchExpressionExecutionFlags.ThreadedEvaluation) && !c.HasFlag(SearchExpressionExecutionFlags.PassNull);
var executeContext = c.runtime.current;
var timeoutWatch = new System.Diagnostics.Stopwatch();
timeoutWatch.Start();
foreach (var r in evaluator.execute(executeContext))
{
if (r != null)
{
timeoutWatch.Restart();
yield return(r);
}
else if (!skipNull)
{
if (timeoutWatch.Elapsed.TotalSeconds > 3.0d)
{
c.ThrowError("Timeout");
}
yield return(null);
}
}
}
}
