F10 SLICE-2: add ProposalView + renderReview combined on-state render (#29)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/trackChangesModel.ts

@@ -410,6 +410,76 @@ export function renderPlain(currentText: string, opts: RenderOptions = {}): stri
   }
 }
 
+export interface ProposalView {
+  id: string;
+  /** resolved offsets in currentText; null when the anchor did not resolve. */
+  anchorStart: number | null;
+  anchorEnd: number | null;
+  /** the text the proposal would replace (fp.text), for the struck "before". */
+  replaced: string;
+  /** the proposed replacement text. */
+  replacement: string;
+}
+
+function proposalBlockHtml(p: ProposalView, render: (src: string) => string): string {
+  const safe = (src: string): string => {
+    try {
+      return render(src);
+    } catch (err) {
+      return chip(err instanceof Error ? err.message : String(err));
+    }
+  };
+  const unanchored = p.anchorStart === null ? " cw-proposal-unanchored" : "";
+  const before = p.replaced ? `<del class="cw-del">${safe(p.replaced)}</del>` : "";
+  const after = `<ins class="cw-add">${safe(p.replacement)}</ins>`;
+  const actions =
+    `<span class="cw-actions">` +
+    `<button class="cw-accept" data-action="accept">✓</button>` +
+    `<button class="cw-reject" data-action="reject">✗</button>` +
+    `</span>`;
+  return `<div class="cw-proposal${unanchored}" data-proposal-id="${p.id}">${actions}${before}${after}</div>`;
+}
+
+function renderReviewOp(
+  op: BlockOp,
+  render: (src: string) => string,
+  colored: (raw: string) => string,
+): string {
+  if (op.kind === "removed") return renderOp(op, render);
+  if (op.kind === "changed" && op.atomic) return renderOp(op, render);
+  if (op.kind === "changed") return renderOp(op, render); // word-merged <ins>/<del>
+  return `<div class="cw-blk ${op.kind === "added" ? "cw-added" : "cw-unchanged"}">${colored(op.block.raw)}</div>`;
+}
+
+/**
+ * On-state body (INV-33): the F7 baseline diff — added/changed PROSE author-colored
+ * via colorByAuthor (F9 sentinels), deletions struck — overlaid with F4 pending
+ * proposals as blue cw-proposal blocks (✓/✗). One pass, pure, vscode-free.
+ * Resolved proposals append after the diff body; unresolved ones append as trailing
+ * cw-proposal-unanchored blocks (never dropped — INV-34).
+ */
+export function renderReview(
+  baselineText: string,
+  currentText: string,
+  authorSpans: AuthorSpan[],
+  proposals: ProposalView[],
+  opts: RenderOptions = {},
+): string {
+  const render = opts.render ?? defaultRender;
+  const ranges = splitBlocksWithRanges(currentText);
+  const ops = diffBlocks(baselineText, currentText);
+  const colored = (raw: string): string => {
+    const blk = ranges.find((r) => r.raw === raw);
+    if (!blk) return render(raw);
+    return colorByAuthor(raw, blk.start, authorSpans, render);
+  };
+  const bodyParts = ops.map((op) => renderReviewOp(op, render, colored));
+  const anchored = proposals.filter((p) => p.anchorStart !== null);
+  const unanchored = proposals.filter((p) => p.anchorStart === null);
+  const proposalParts = [...anchored, ...unanchored].map((p) => proposalBlockHtml(p, render));
+  return [...bodyParts, ...proposalParts].join("\n");
+}
+
 /** Pure entry point: annotated HTML body for the preview (INV-22). */
 export function renderTrackChanges(
   baselineText: string,