public static void ParseStream(Stream stream, object rootSubject, VocabTerm rootTerm)
{
using (var reader = new JsonTextReader(new StreamReader(stream)))
{
var ostack = new Stack<Context>();
Context currentContext = null;
Func<Context, object, Context> currentParser = null;
while (reader.Read())
{
switch (reader.TokenType)
{
case JsonToken.StartObject:
if (currentContext == null)
{
currentContext = new Context(rootSubject, rootTerm);
currentParser = rootTerm.Parser;
}
else
{
// Save current context before creating new context
ostack.Push(currentContext);
if (currentParser != null) // If we have a handler to create a new context object
{
// Update to new Context unless we are walking an Array of objects
var newContext = currentParser(currentContext, currentContext.LastProperty);
if (newContext != null)
{
currentContext = newContext;
}
}
else
{
currentContext = new Context(null, null); // Unknown object
}
}
DiagSource?.Write("Hapikit.JsonStreamingParser.NewObject", currentContext);
break;
case JsonToken.StartArray:
DiagSource?.Write("Hapikit.JsonStreamingParser.StartArray", currentContext);
break;
case JsonToken.EndArray:
DiagSource?.Write("Hapikit.JsonStreamingParser.EndArray", currentContext);
break;
case JsonToken.EndObject:
// Update context object
DiagSource?.Write("Hapikit.JsonStreamingParser.EndObject", currentContext);
if (ostack.Count > 0)
{
currentParser = currentContext.TermMap?.Parser;
currentContext = ostack.Pop();
}
break;
case JsonToken.PropertyName:
// Determine new VocabTerm based on new Property
currentContext.LastProperty = reader.Value.ToString();
currentParser = currentContext.TermMap?.FindParser(currentContext.LastProperty);
DiagSource?.Write("Hapikit.JsonStreamingParser.PropertyName", currentContext.TermMap);
break;
case JsonToken.Integer:
case JsonToken.Boolean:
case JsonToken.String:
// Use VocabTerm Parser to Update Subject based on the current Term.
if (currentParser != null)
{
DiagSource?.Write("Hapikit.JsonStreamingParser.PropertyValue", reader.Value);
currentParser(currentContext, reader.Value);
}
else
{
DiagSource?.Write("Hapikit.JsonStreamingParser.MissingTermHandler", new { Context = currentContext, Value = reader.Value });
}
break;
}
}
}
}
