Wire HtmlViewerAdapter into ViewerShell for HTML/Markdown documents

UploadDropzone accepts HTML/MD files; ViewerShell routes by
representationType; PendingSelection uses SelectionCapture union.

src/work/UploadDropzone.tsx

@@ -1,37 +1,23 @@
 /**
- * UploadDropzone — drag-drop + file-picker for uploading PDFs into the
- * active session.
- *
- * On every successful drop:
- *   1. read each File as bytes,
- *   2. run the source-layer `ingestPdfFromFile` (mints the blob URL
- *      via the session's `PdfByteStore`),
- *   3. register the resulting `{document, representation}` with the
- *      engine,
- *   4. activate the most-recently-uploaded document.
- *
- * Failures (non-PDFs, ingest errors) are surfaced inline above the
- * dropzone; the caller doesn't need a separate toast for them.
- *
- * ── Extraction decision (CWORK-WP-0001 T03) ──────────────────────────
- * This component lives in `citation-work` rather than the umbrella app.
- * Its only dependencies are `@source` (PDF ingestion) and the local
- * engine/session hooks — both inside the review-workspace boundary — so
- * hosting it here lets the package render a complete review shell,
- * including the upload affordance, without any umbrella-local imports.
- * `ReviewShell` still exposes an `upload` slot so a consumer may swap in
- * its own affordance; when the slot is omitted, this default is used.
+ * UploadDropzone — drag-drop + file-picker for uploading documents into the
+ * active session (PDF, HTML, Markdown).
  */
 
 import { useCallback, useRef, useState } from "react";
 
-import { ingestPdfFromFile } from "@source/index";
+import {
+  ingestHtmlFromFile,
+  ingestMarkdownFromFile,
+  ingestPdfFromFile,
+} from "@source/index";
 import {
   useActiveDocumentId,
   useEngine,
   usePdfByteStore,
 } from "./EngineContext";
 
+type UploadFormat = "pdf" | "html" | "markdown" | "unsupported";
+
 interface UploadEntry {
   readonly file: File;
   status: "queued" | "uploading" | "done" | "error";
@@ -43,6 +29,22 @@ export interface UploadDropzoneProps {
   readonly onUploaded?: (documentId: import("@shared/ids").DocumentId) => void;
 }
 
+function detectFormat(file: File): UploadFormat {
+  const name = file.name.toLowerCase();
+  if (file.type === "application/pdf" || name.endsWith(".pdf")) return "pdf";
+  if (file.type === "text/html" || name.endsWith(".html") || name.endsWith(".htm")) {
+    return "html";
+  }
+  if (
+    file.type === "text/markdown"
+    || name.endsWith(".md")
+    || name.endsWith(".markdown")
+  ) {
+    return "markdown";
+  }
+  return "unsupported";
+}
+
 export function UploadDropzone({ onUploaded }: UploadDropzoneProps) {
   const engine = useEngine();
   const byteStore = usePdfByteStore();
@@ -55,14 +57,15 @@ export function UploadDropzone({ onUploaded }: UploadDropzoneProps) {
     async (files: readonly File[]) => {
       if (files.length === 0) return;
       const initial: UploadEntry[] = files.map((file) => {
-        const isPdf =
-          file.type === "application/pdf" || file.name.toLowerCase().endsWith(".pdf");
-        if (isPdf) return { file, status: "queued" };
-        return {
-          file,
-          status: "error",
-          error: "Not a PDF (only application/pdf accepted)",
-        };
+        const format = detectFormat(file);
+        if (format === "unsupported") {
+          return {
+            file,
+            status: "error",
+            error: "Unsupported format (PDF, HTML, or Markdown only)",
+          };
+        }
+        return { file, status: "queued" };
       });
       setEntries((prev) => [...prev, ...initial]);
 
@@ -72,14 +75,16 @@ export function UploadDropzone({ onUploaded }: UploadDropzoneProps) {
         entry.status = "uploading";
         setEntries((prev) => [...prev]);
         try {
-          const { document, representation } = await ingestPdfFromFile(
-            entry.file,
-            byteStore,
-          );
-          engine.documents.register({ document, representation });
+          const format = detectFormat(entry.file);
+          const ingested = await (format === "html"
+            ? ingestHtmlFromFile(entry.file, byteStore)
+            : format === "markdown"
+              ? ingestMarkdownFromFile(entry.file, byteStore)
+              : ingestPdfFromFile(entry.file, byteStore));
+          engine.documents.register(ingested);
           entry.status = "done";
-          lastDocumentId = document.id;
-          onUploaded?.(document.id);
+          lastDocumentId = ingested.document.id;
+          onUploaded?.(ingested.document.id);
         } catch (err) {
           entry.status = "error";
           entry.error = err instanceof Error ? err.message : String(err);
@@ -118,7 +123,6 @@ export function UploadDropzone({ onUploaded }: UploadDropzoneProps) {
     (e: React.ChangeEvent<HTMLInputElement>) => {
       const files = e.target.files ? Array.from(e.target.files) : [];
       void processFiles(files);
-      // Reset so the same filename can be picked again.
       e.target.value = "";
     },
     [processFiles],
@@ -131,7 +135,7 @@ export function UploadDropzone({ onUploaded }: UploadDropzoneProps) {
         onDragOver={onDragOver}
         onDragLeave={onDragLeave}
         role="region"
-        aria-label="PDF upload"
+        aria-label="Document upload"
         style={{
           border: `2px dashed ${isOver ? "#0050b3" : "#bbb"}`,
           background: isOver ? "#e8f0ff" : "#fafafa",
@@ -142,7 +146,7 @@ export function UploadDropzone({ onUploaded }: UploadDropzoneProps) {
           borderRadius: 4,
         }}
       >
-        <div>Drop PDF files here</div>
+        <div>Drop PDF, HTML, or Markdown files here</div>
         <div style={{ margin: "6px 0", color: "#888" }}>or</div>
         <button
           type="button"
@@ -156,12 +160,12 @@ export function UploadDropzone({ onUploaded }: UploadDropzoneProps) {
             cursor: "pointer",
           }}
         >
-          Choose PDF…
+          Choose file…
         </button>
         <input
           ref={fileInputRef}
           type="file"
-          accept="application/pdf,.pdf"
+          accept="application/pdf,.pdf,text/html,.html,.htm,text/markdown,.md,.markdown"
           multiple
           onChange={onPicked}
           style={{ display: "none" }}
@@ -195,4 +199,4 @@ export function UploadDropzone({ onUploaded }: UploadDropzoneProps) {
       )}
     </div>
   );
-}
+}