public static void Iterate(
BindingContext context,
EncodedTextWriter writer,
ChainSegment[] blockParamsVariables,
object target,
TemplateDelegate template,
TemplateDelegate ifEmpty)
{
if (!HandlebarsUtils.IsTruthy(target))
{
using var frame = context.CreateFrame(context.Value);
ifEmpty(writer, frame);
return;
}
if (!ObjectDescriptor.TryCreate(target, context.Configuration.ObjectDescriptorProvider, out var descriptor))
{
throw new HandlebarsRuntimeException($"Cannot create ObjectDescriptor for type {descriptor.DescribedType}");
}
if (descriptor.Iterator == null)
{
throw new HandlebarsRuntimeException($"Type {descriptor.DescribedType} does not support iteration");
}
descriptor.Iterator.Iterate(writer, context, blockParamsVariables, target, template, ifEmpty);
}
private static void IterateObjectWithStaticProperties(
BindingContext context,
EncodedTextWriter writer,
ChainSegment[] blockParamsVariables,
ObjectDescriptor descriptor,
object target,
IList <ChainSegment> properties,
Type targetType,
TemplateDelegate template,
TemplateDelegate ifEmpty)
{
using var innerContext = context.CreateFrame();
var iterator = new ObjectIteratorValues(innerContext);
var blockParams = new BlockParamsValues(innerContext, blockParamsVariables);
blockParams.CreateProperty(0, out var _0);
blockParams.CreateProperty(1, out var _1);
var count = properties.Count;
var accessor = new MemberAccessor(target, descriptor);
var iterationIndex = 0;
var lastIndex = count - 1;
object iteratorValue;
ChainSegment iteratorKey;
for (; iterationIndex < count; iterationIndex++)
{
iteratorKey = properties[iterationIndex];
iterator.Index = iterationIndex;
iterator.Key = iteratorKey;
if (iterationIndex == 1)
{
iterator.First = BoxedValues.False;
}
if (iterationIndex == lastIndex)
{
iterator.Last = BoxedValues.True;
}
iteratorValue = accessor[iteratorKey];
iterator.Value = iteratorValue;
innerContext.Value = iteratorValue;
blockParams[_0] = iteratorValue;
blockParams[_1] = iteratorKey;
template(writer, innerContext);
}
if (iterationIndex == 0)
{
innerContext.Value = context.Value;
ifEmpty(writer, innerContext);
}
}
private static void IterateObject(
BindingContext context,
EncodedTextWriter writer,
ObjectDescriptor descriptor,
ChainSegment[] blockParamsVariables,
object target,
IEnumerable properties,
Type targetType,
TemplateDelegate template,
TemplateDelegate ifEmpty)
{
using var innerContext = context.CreateFrame();
var iterator = new ObjectIteratorValues(innerContext);
var blockParams = new BlockParamsValues(innerContext, blockParamsVariables);
blockParams.CreateProperty(0, out var _0);
blockParams.CreateProperty(1, out var _1);
var accessor = new MemberAccessor(target, descriptor);
var enumerable = new ExtendedEnumerator <object>(properties.GetEnumerator());
var enumerated = false;
object iteratorValue;
ChainSegment iteratorKey;
while (enumerable.MoveNext())
{
enumerated = true;
var enumerableValue = enumerable.Current;
iteratorKey = ChainSegment.Create(enumerableValue.Value);
iterator.Key = iteratorKey;
iterator.Index = enumerableValue.Index;
if (enumerableValue.Index == 1)
{
iterator.First = BoxedValues.False;
}
if (enumerableValue.IsLast)
{
iterator.Last = BoxedValues.True;
}
iteratorValue = accessor[iteratorKey];
iterator.Value = iteratorValue;
innerContext.Value = iteratorValue;
blockParams[_0] = iteratorValue;
blockParams[_1] = iteratorKey;
template(writer, innerContext);
}
if (!enumerated)
{
innerContext.Value = context.Value;
ifEmpty(writer, innerContext);
}
}
public static void Iterate(
BindingContext context,
EncodedTextWriter writer,
ChainSegment[] blockParamsVariables,
object target,
TemplateDelegate template,
TemplateDelegate ifEmpty)
{
if (!HandlebarsUtils.IsTruthy(target))
{
using var frame = context.CreateFrame(context.Value);
ifEmpty(writer, frame);
return;
}
var targetType = target.GetType();
if (!context.Configuration.ObjectDescriptorProvider.TryGetDescriptor(targetType, out var descriptor))
{
using var frame = context.CreateFrame(context.Value);
ifEmpty(writer, frame);
return;
}
if (!descriptor.ShouldEnumerate)
{
var properties = descriptor.GetProperties(descriptor, target);
if (properties is IList <ChainSegment> propertiesList)
{
IterateObjectWithStaticProperties(context, writer, blockParamsVariables, descriptor, target, propertiesList, targetType, template, ifEmpty);
return;
}
IterateObject(context, writer, descriptor, blockParamsVariables, target, properties, targetType, template, ifEmpty);
return;
}
if (target is IList list)
{
IterateList(context, writer, blockParamsVariables, list, template, ifEmpty);
return;
}
IterateEnumerable(context, writer, blockParamsVariables, (IEnumerable)target, template, ifEmpty);
}
private static void IterateEnumerable(
BindingContext context,
EncodedTextWriter writer,
ChainSegment[] blockParamsVariables,
IEnumerable target,
TemplateDelegate template,
TemplateDelegate ifEmpty)
{
using var innerContext = context.CreateFrame();
var iterator = new IteratorValues(innerContext);
var blockParams = new BlockParamsValues(innerContext, blockParamsVariables);
blockParams.CreateProperty(0, out var _0);
blockParams.CreateProperty(1, out var _1);
var enumerator = new ExtendedEnumerator <object>(target.GetEnumerator());
var enumerated = false;
object boxedIndex;
object iteratorValue;
while (enumerator.MoveNext())
{
enumerated = true;
var enumerableValue = enumerator.Current;
if (enumerableValue.Index == 1)
{
iterator.First = BoxedValues.False;
}
if (enumerableValue.IsLast)
{
iterator.Last = BoxedValues.True;
}
boxedIndex = enumerableValue.Index;
iteratorValue = enumerableValue.Value;
iterator.Value = iteratorValue;
iterator.Index = boxedIndex;
blockParams[_0] = iteratorValue;
blockParams[_1] = boxedIndex;
innerContext.Value = iteratorValue;
template(writer, innerContext);
}
if (!enumerated)
{
innerContext.Value = context.Value;
ifEmpty(writer, innerContext);
}
}
private static void IterateList(
BindingContext context,
EncodedTextWriter writer,
ChainSegment[] blockParamsVariables,
IList target,
TemplateDelegate template,
TemplateDelegate ifEmpty)
{
using var innerContext = context.CreateFrame();
var iterator = new IteratorValues(innerContext);
var blockParams = new BlockParamsValues(innerContext, blockParamsVariables);
blockParams.CreateProperty(0, out var _0);
blockParams.CreateProperty(1, out var _1);
var count = target.Count;
object boxedIndex;
object iteratorValue;
var iterationIndex = 0;
var lastIndex = count - 1;
for (; iterationIndex < count; iterationIndex++)
{
iteratorValue = target[iterationIndex];
iterator.Value = iteratorValue;
if (iterationIndex == 1)
{
iterator.First = BoxedValues.False;
}
if (iterationIndex == lastIndex)
{
iterator.Last = BoxedValues.True;
}
boxedIndex = iterationIndex;
iterator.Index = boxedIndex;
blockParams[_0] = iteratorValue;
blockParams[_1] = boxedIndex;
innerContext.Value = iteratorValue;
template(writer, innerContext);
}
if (iterationIndex == 0)
{
innerContext.Value = context.Value;
ifEmpty(writer, innerContext);
}
}
private static void RenderSection(object value,
BindingContext context,
EncodedTextWriter writer,
TemplateDelegate body,
TemplateDelegate inversion)
{
switch (value)
{
case bool boolValue when boolValue:
body(writer, context);
return;
case null:
case object _ when HandlebarsUtils.IsFalsyOrEmpty(value):
inversion(writer, context);
return;
case string _:
{
using var frame = context.CreateFrame(value);
body(writer, frame);
return;
}
case IEnumerable enumerable:
Iterator.Iterate(context, writer, BlockParamsVariables, enumerable, body, inversion);
break;
default:
{
using var frame = context.CreateFrame(value);
body(writer, frame);
break;
}
}
}