Expression Struct(IParser parser, RuntimeSchema schema, bool isBase)
{
var metadata = schema.HasValue ? Expression.Constant(schema.StructDef.metadata) : noMetadata;
var baseSchema = schema.HasBase ? schema.GetBaseSchema() : RuntimeSchema.Empty;
return(parser.Apply(new Transform(
Begin: () => isBase ? writer.WriteBaseBegin(metadata) : writer.WriteStructBegin(metadata),
End: () => isBase ? writer.WriteBaseEnd() : writer.WriteStructEnd(),
Fields: schema.HasValue ?
from field in schema.StructDef.fields
select new Field(
Id: field.id,
Value: (fieldParser, fieldType) =>
Expression.Block(
writer.WriteFieldBegin(fieldType, field.id, field.metadata),
Value(fieldParser, fieldType, schema.GetFieldSchema(field)),
writer.WriteFieldEnd()),
Omitted: () => writer.WriteFieldOmitted(field.type.id, field.id, field.metadata)) :
null,
UnknownField: (fieldParser, fieldType, fieldId) =>
Expression.Block(
writer.WriteFieldBegin(fieldType, fieldId, noMetadata),
Value(fieldParser, fieldType),
writer.WriteFieldEnd()),
Base: baseParser =>
baseSchema.HasValue ? Struct(baseParser, baseSchema, isBase: true) : Expression.Empty(),
UnknownEnd: () => writer.WriteBaseEnd())));
}
Expression Struct(IParser parser, Expression var, Type schemaType, bool initialize)
{
var body = new List <Expression>();
if (initialize)
{
body.Add(Expression.Assign(var, newObject(var.Type, schemaType)));
}
ITransform transform;
if (parser.HierarchyDepth > schemaType.GetHierarchyDepth())
{
// Parser inheritance hierarchy is deeper than the type we are deserializing.
// Recurse until hierarchies align.
transform = new Transform(
Base: baseParser => Struct(baseParser, var, schemaType, initialize: false));
}
else
{
var baseType = schemaType.GetBaseSchemaType();
transform = new Transform(
Fields:
from field in schemaType.GetSchemaFields()
select new Field(
Id: field.Id,
Value: (fieldParser, fieldType) => FieldValue(
fieldParser,
DataExpression.PropertyOrField(var, field.Name),
fieldType,
field.GetSchemaType(),
field.GetDefaultValue() == null),
Omitted: () => field.GetModifier() == Modifier.Required ?
ThrowExpression.RequiredFieldMissingException(
field.DeclaringType.Name, Expression.Constant(field.Name)) :
Expression.Empty()),
Base: baseParser => baseType != null
? Struct(baseParser, Expression.Convert(var, baseType.GetObjectType()), baseType, initialize: false)
: Expression.Empty());
}
body.Add(parser.Apply(transform));
return(Expression.Block(body));
}