public override async Task ProcessAsync(TagHelperContext context, TagHelperOutput output)
{
if (string.IsNullOrEmpty(Capture))
{
return;
}
var attributes = context.AllAttributes
.Where(a => !SystemAttributes.Contains(a.Name))
.ToDictionary(k => k.Name, v => v.Value);
var content = await output.GetChildContentAsync();
var key = $"Element_{Capture}";
ContentCapture capture = null;
if (ViewContext.HttpContext.Items.ContainsKey(key))
{
capture = ViewContext.HttpContext.Items[key] as ContentCapture;
}
if (capture == null)
{
capture = new ContentCapture();
ViewContext.HttpContext.Items.Add(key, capture);
}
var order = Priority ?? int.MaxValue;
capture.Add(content, attributes, output.TagName, NoTag.GetValueOrDefault(false), order, AllowMerge);
output.SuppressOutput();
}
private async Task RenderBlocks(TextWriter tw, ContentCapture capture)
{
const string srcAttribute = "src";
const string idAttribute = "id";
var blocks = capture.Blocks;
if (!string.IsNullOrWhiteSpace(NoDuplicateSource) && bool.TryParse(NoDuplicateSource, out var hasBoolNoDuplicateSource) && hasBoolNoDuplicateSource)
{
blocks = blocks
.GroupBy(b => b.Attributes.ContainsKey(srcAttribute) ? b.Attributes[srcAttribute] :
b.Attributes.ContainsKey(idAttribute) ? b.Attributes[idAttribute] : Guid.NewGuid())
.Select(b => b.First());
}
else if (!string.IsNullOrWhiteSpace(NoDuplicateSource))
{
blocks = blocks
.GroupBy(b => b.Attributes.ContainsKey(NoDuplicateSource) ? b.Attributes[NoDuplicateSource] : Guid.NewGuid())
.Select(b => b.First());
}
var orderedBlocks = blocks.OrderBy(b => b.Order);
var mergableBlocks = orderedBlocks.Where(b =>
((AutoMerge && (!b.CanMerge.HasValue || b.CanMerge.Value)) ||
(!AutoMerge && b.CanMerge.HasValue && b.CanMerge.Value)) &&
!b.Content.IsEmptyOrWhiteSpace);
var otherBlocks = orderedBlocks.Except(mergableBlocks);
await RenderMergedBlocks(tw, mergableBlocks);
await RenderSeparateBlocks(tw, otherBlocks);
}
private async Task RenderBlocks(TextWriter tw, ContentCapture capture)
{
var blocks = capture.Blocks;
if (NoDuplicates)
{
blocks = blocks
.GroupBy(b => b.Attributes.ContainsKey(NoDuplicateSource) ? b.Attributes[NoDuplicateSource] : Guid.NewGuid())
.Select(b => b.First());
}
var orderedBlocks = blocks.OrderBy(b => b.Order);
var mergableBlocks = orderedBlocks.Where(b =>
((AutoMerge && (!b.CanMerge.HasValue || b.CanMerge.Value)) ||
(!AutoMerge && b.CanMerge.HasValue && b.CanMerge.Value)) &&
!b.Content.IsEmptyOrWhiteSpace);
var otherBlocks = orderedBlocks.Except(mergableBlocks);
await RenderMergedBlocks(tw, mergableBlocks);
await RenderSeparateBlocks(tw, otherBlocks);
}