OfficeIMO.Html 0.1.3

OfficeIMO.Html

OfficeIMO.Html contains shared HTML ingestion primitives and first-party HTML bridge APIs used by OfficeIMO converters.

It owns the reusable parts that should behave consistently across HTML-to-Markdown, HTML-to-Word, HTML-to/from-RTF, and HTML-backed PDF workflows:

• URL policy evaluation and base URI resolution
• AngleSharp document parsing helpers
• DOM traversal facts and node/depth limit tracking
• image source discovery for img, lazy-loading attributes, srcset, and picture/source
• image data URI parsing and media-type extension mapping
• semantic HTML to/from RTF conversion over the dependency-free OfficeIMO.Rtf model

It does not replace output-specific engines. Markdown AST creation, Word document generation, RTF document generation, and PDF orchestration stay in their owning packages such as OfficeIMO.Markdown.Html, OfficeIMO.Word.Html, OfficeIMO.Rtf, and OfficeIMO.Html.Pdf.

RTF Bridge

using OfficeIMO.Html;

RtfDocument document = "<p>Hello <strong>RTF</strong></p>".ToRtfDocument();
string rtf = document.ToRtf();
string html = document.ToHtml();

RTF-to-RTF editing in OfficeIMO.Rtf remains the lossless preservation path. The HTML bridge is semantic: it preserves supported text, inline formatting, links, lists, tables, bookmarks, fields, form fields, notes, tracked revisions, object metadata, shape metadata, and embedded PNG/JPEG images without Office/COM automation.

URL Policy

var policy = HtmlUrlPolicy.CreateWebOnlyProfile();
string href = HtmlUrlPolicyEvaluator.ResolveUrl(
    "/docs/start.html",
    new Uri("https://example.com/"),
    policy);

Parsing And Base URIs

var document = HtmlDocumentParser.ParseDocument(html);
Uri? baseUri = HtmlDocumentParser.ResolveEffectiveBaseUri(
    document,
    new Uri("https://example.com/articles/"));

Traversal Limits

HtmlDomLimitTracker? tracker = HtmlDomLimitTracker.Create(
    maxHtmlNodes: 10000,
    maxHtmlDepth: 64);

Converter packages use these primitives to keep bounded HTML ingestion behavior consistent while still reporting converter-specific diagnostics.

Shared Diagnostics And Gallery Contracts

var report = new HtmlDiagnosticReport();
report.Add("OfficeIMO.Word.Html", "HtmlCommentSkipped", "Comment skipped");

var scenario = new HtmlCapabilityGalleryScenario(
    "quarterly-report",
    "Quarterly Report",
    "Word HTML",
    "HTML import, DOCX validation, and round-trip export proof");

HtmlDiagnosticReport and the capability-gallery contracts provide a common shape for HTML converters, PDF bridges, readers, tests, and future documentation generators. Format-specific packages can keep their existing compatibility APIs while also publishing shared diagnostics and artifact metadata for market-facing proof galleries.

Conversion Document And Normalized HTML

var conversion = HtmlConversionDocumentBuilder.Build(html, new HtmlConversionDocumentOptions {
    Profile = HtmlConversionProfile.Document,
    BaseUri = new Uri("https://example.com/reports/"),
    UrlPolicy = HtmlUrlPolicy.CreateWebOnlyProfile()
});

string normalized = conversion.NormalizedHtml;
var resources = conversion.ResourcePlan.GetSummary(HtmlResourceKind.Image);
var styles = conversion.StyleSummary;

HtmlConversionDocument is the shared conversion contract for OfficeIMO HTML workflows. It keeps the original source HTML together with the logical document model, computed-style summary, resource manifest, resource dependency plan, normalized HTML, and profile contract.

Target packages can accept this shared document while keeping target-specific rendering in their owning packages. For example, OfficeIMO.Word.Html can load it into WordDocument, OfficeIMO.Markdown.Html can render Markdown from it, and OfficeIMO.Html.Pdf can choose the matching bridge profile.

Normalized HTML output is policy-aware: URL-bearing attributes are resolved against the configured base URI, disallowed URLs are removed, boolean attributes are normalized, event-handler attributes are stripped by default, and non-document executable elements are skipped. It is intended for clean review, gallery proof, and downstream adapter input selection, not for pretending OfficeIMO is a browser layout engine.

Image Sources

string source = HtmlImageSourceResolver.ResolveImageSource(
    imageElement,
    baseUri,
    HtmlUrlPolicy.CreateOfficeIMOProfile());

Image Data URIs

if (HtmlImageDataUri.TryParse(source, out var dataUri) && dataUri.IsBase64) {
    byte[] bytes = dataUri.DecodeBytes();
    string extension = dataUri.FileExtension;
}