From ed662c3a3a8add946f9814dff538bb17cda41610 Mon Sep 17 00:00:00 2001
From: timmy <timmy@stackchain.ai>
Date: Tue, 25 Aug 2026 06:08:22 +0000
Subject: [PATCH] feat: apply mobile review suggestions (Closes #1382)

---
 frontend/dashboard.css                        |   9 ++
 frontend/index.html                           |  18 ++-
 frontend/pull-sheet.js                        |  93 ++++++++++++++++
 src/gitea_proxy.py                            |  17 +++
 ..._mobile_apply_review_suggestion_release.py | 103 ++++++++++++++++++
 tests/test_pull_api.py                        |  28 +++++
 6 files changed, 267 insertions(+), 1 deletion(-)
 create mode 100644 tests/e2e/test_mobile_apply_review_suggestion_release.py

diff --git a/frontend/dashboard.css b/frontend/dashboard.css
index 0dd7ffd..73a6c09 100644
--- a/frontend/dashboard.css
+++ b/frontend/dashboard.css
@@ -765,6 +765,15 @@ textarea { resize: vertical; min-height: 120px; }
 .review-feedback { display:grid; gap:8px; }
 .review-feedback label { display:grid; gap:6px; }
 .review-feedback select { min-height:44px; padding:8px; border-radius:8px; border:1px solid #1f3a5f; background:#0b1526; color:#e5e7eb; }
+.pull-feedback-code-actions, .pull-feedback-file-actions { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:8px; }
+.pull-feedback-code-actions button, .pull-feedback-file-actions button { min-height:44px; }
+.pull-feedback-suggestion-preview { min-width:0; display:grid; gap:10px; margin:10px 0; padding:10px; border:1px solid #31577f; border-radius:10px; background:#07101e; }
+.pull-feedback-suggestion-preview[hidden] { display:none; }
+.pull-feedback-suggestion-preview h5 { margin:0; }
+.pull-feedback-suggestion-change { display:grid; gap:8px; min-width:0; }
+.pull-feedback-suggestion-change > div { min-width:0; }
+.pull-feedback-suggestion-change pre { box-sizing:border-box; max-width:100%; max-height:160px; white-space:pre-wrap; overflow-wrap:anywhere; word-break:break-word; }
+.pull-feedback-suggestion-preview input { box-sizing:border-box; width:100%; min-height:44px; }
 .review-handoff { position:sticky; bottom:0; z-index:3; display:grid; gap:8px; padding:10px 4px; padding-bottom:calc(10px + env(safe-area-inset-bottom)); background:rgba(11,21,38,.98); border-top:1px solid #2a496e; }
 .review-handoff button { min-height:44px; }
 .review-handoff-link { min-height:44px; display:flex; align-items:center; justify-content:center; border:1px solid #60a5fa; border-radius:8px; color:#bfdbfe; font-weight:700; text-decoration:none; }
diff --git a/frontend/index.html b/frontend/index.html
index 201e5ff..0ee2928 100644
--- a/frontend/index.html
+++ b/frontend/index.html
@@ -1741,7 +1741,23 @@
           <p class="small" id="pull-feedback-location"></p>
           <p id="pull-feedback-body"></p>
           <div class="small" id="pull-feedback-context" aria-live="polite"></div>
-          <button id="make-pull-feedback-fix" type="button" hidden>Make code change</button>
+          <div class="pull-feedback-code-actions">
+            <button id="review-pull-feedback-suggestion" type="button" hidden>Review suggested change</button>
+            <button id="make-pull-feedback-fix" type="button" hidden>Edit full file</button>
+          </div>
+          <section class="pull-feedback-suggestion-preview" id="pull-feedback-suggestion-preview" aria-labelledby="pull-feedback-suggestion-heading" hidden>
+            <h5 id="pull-feedback-suggestion-heading">Suggested change</h5>
+            <div class="pull-feedback-suggestion-change">
+              <div><span class="small">Current line</span><pre id="pull-feedback-suggestion-before"></pre></div>
+              <div><span class="small">Suggested replacement</span><pre id="pull-feedback-suggestion-after"></pre></div>
+            </div>
+            <label for="pull-feedback-suggestion-message">Commit message</label>
+            <input id="pull-feedback-suggestion-message" maxlength="120" value="fix: apply review suggestion">
+            <div class="pull-feedback-file-actions">
+              <button id="cancel-pull-feedback-suggestion" type="button" hidden>Cancel suggestion</button>
+              <button id="apply-pull-feedback-suggestion" type="button" hidden>Commit suggested change</button>
+            </div>
+          </section>
           <section class="pull-feedback-file-editor" id="pull-feedback-file-editor" hidden>
             <h5>Edit <span id="pull-feedback-file-path"></span></h5>
             <label for="pull-feedback-file-content">File content</label>
diff --git a/frontend/pull-sheet.js b/frontend/pull-sheet.js
index 7bf104b..c6f5435 100644
--- a/frontend/pull-sheet.js
+++ b/frontend/pull-sheet.js
@@ -413,11 +413,29 @@ function bindFeedbackControls(doc, controller, getSelected, getDetail, getLogin)
   const save = () => {
     if (active) controller.saveFeedbackPass(active.item, active.detail, active.reviewer, active.login, active.state);
   };
+  const clearSuggestion = () => {
+    qs('#pull-feedback-suggestion-preview').hidden = true;
+    qs('#cancel-pull-feedback-suggestion').hidden = true;
+    qs('#apply-pull-feedback-suggestion').hidden = true;
+    if (active) active.suggestion = null;
+  };
+  const suggestedFile = (file, suggestion) => {
+    const line = Number(suggestion?.line);
+    if (!Number.isInteger(line) || line < 1 || typeof suggestion?.content !== 'string') return null;
+    const trailingNewline = file.content.endsWith('\n');
+    const lines = file.content.split('\n');
+    if (trailingNewline) lines.pop();
+    if (line > lines.length) return null;
+    const before = lines[line - 1];
+    lines.splice(line - 1, 1, ...suggestion.content.split('\n'));
+    return { before, after:suggestion.content, content:lines.join('\n') + (trailingNewline ? '\n' : '') };
+  };
   const render = () => {
     if (!active) return;
     const items = comments();
     active.state.index = Math.max(0, Math.min(Number(active.state.index) || 0, items.length - 1));
     const comment = current();
+    if (active.suggestion && active.suggestion.commentId !== comment.id) clearSuggestion();
     const response = active.state.responses[String(comment.id)] || {};
     qs('#pull-feedback-progress').textContent = 'Comment ' + (active.state.index + 1) + ' of ' + items.length;
     qs('#pull-feedback-heading').textContent = 'Address @' + active.reviewer.login + '’s feedback';
@@ -434,6 +452,14 @@ function bindFeedbackControls(doc, controller, getSelected, getDetail, getLogin)
     qs('#request-feedback-review').hidden = active.state.posted !== true;
     qs('#make-pull-feedback-fix').hidden = active.detail?.capabilities?.authored !== true ||
       active.detail?.state !== 'open' || active.detail?.merged === true || !comment.path;
+    const canSuggest = active.detail?.capabilities?.authored === true && active.detail?.state === 'open' &&
+      active.detail?.merged !== true && active.reviewer?.head_sha === active.detail?.head_sha &&
+      comment.suggestion?.line === comment.line && typeof comment.suggestion?.content === 'string';
+    qs('#review-pull-feedback-suggestion').hidden = !canSuggest;
+    qs('#review-pull-feedback-suggestion').disabled = canSuggest && globalThis.navigator?.onLine === false;
+    if (canSuggest && globalThis.navigator?.onLine === false) {
+      qs('#pull-feedback-status').textContent = 'Reconnect to apply suggestion.';
+    }
     const found = focusPullFile(doc, comment.path);
     qs('#pull-feedback-context').textContent = found ?
       'Matching change opened below.' : 'Matching change is unavailable in this preview.';
@@ -478,13 +504,79 @@ function bindFeedbackControls(doc, controller, getSelected, getDetail, getLogin)
       state:controller.loadFeedbackPass(item, detail, reviewer, login) };
     panel.hidden = false;
     qs('#pull-feedback-file-editor').hidden = true;
+    qs('#pull-feedback-suggestion-preview').hidden = true;
     qs('#cancel-pull-feedback-fix').hidden = true;
     qs('#commit-pull-feedback-fix').hidden = true;
     active.file = null;
+    active.suggestion = null;
     qs('#pull-feedback-status').textContent = active.state.posted ?
       'Response already posted. You can request an updated review.' : 'Progress saves on this device.';
     render();
   });
+  qs('#review-pull-feedback-suggestion').addEventListener('click', async () => {
+    const comment = current();
+    if (!active || !comment?.suggestion || globalThis.navigator?.onLine === false) {
+      qs('#pull-feedback-status').textContent = 'Reconnect to apply suggestion.';
+      return;
+    }
+    const button = qs('#review-pull-feedback-suggestion');
+    button.disabled = true;
+    qs('#pull-feedback-status').textContent = 'Loading the current line for review…';
+    try {
+      const file = await controller.loadFeedbackFile(active.item, comment.path, active.detail.head_sha);
+      if (!active || file.head_sha !== active.detail.head_sha || file.path !== comment.path) return;
+      const change = suggestedFile(file, comment.suggestion);
+      if (!change) throw new Error('The suggested line is no longer available.');
+      active.suggestion = { file, content:change.content, commentId:comment.id };
+      qs('#pull-feedback-suggestion-before').textContent = change.before;
+      qs('#pull-feedback-suggestion-after').textContent = change.after;
+      qs('#pull-feedback-suggestion-message').value = 'fix: apply review suggestion';
+      qs('#pull-feedback-file-editor').hidden = true;
+      qs('#pull-feedback-suggestion-preview').hidden = false;
+      qs('#cancel-pull-feedback-suggestion').hidden = false;
+      qs('#apply-pull-feedback-suggestion').hidden = false;
+      qs('#pull-feedback-status').textContent = 'Review the bounded replacement before committing.';
+      qs('#apply-pull-feedback-suggestion').focus();
+    } catch (error) {
+      qs('#pull-feedback-status').textContent = error.message + ' Use the full-file editor if needed.';
+      button.focus();
+    } finally {
+      button.disabled = false;
+    }
+  });
+  qs('#cancel-pull-feedback-suggestion').addEventListener('click', () => {
+    clearSuggestion();
+    qs('#review-pull-feedback-suggestion').focus();
+  });
+  qs('#apply-pull-feedback-suggestion').addEventListener('click', async () => {
+    if (!active?.suggestion) return;
+    const message = qs('#pull-feedback-suggestion-message').value.trim();
+    if (!message) {
+      qs('#pull-feedback-status').textContent = 'Enter a commit message before committing.';
+      return;
+    }
+    if (!globalThis.confirm('Commit this suggested change to ' + active.item.key + '?')) return;
+    const button = qs('#apply-pull-feedback-suggestion');
+    button.disabled = true;
+    const pending = active.suggestion;
+    qs('#pull-feedback-status').textContent = 'Committing and verifying the suggested change…';
+    try {
+      const result = await controller.commitFeedbackFix(active.item, {
+        path:pending.file.path, content:pending.content, message,
+        expectedHeadSha:pending.file.head_sha, expectedBlobSha:pending.file.blob_sha,
+      });
+      active.detail.head_sha = result.head_sha;
+      active.state.headSha = result.head_sha;
+      clearSuggestion();
+      save();
+      qs('#pull-feedback-status').textContent = 'Suggested change committed. Mark the comment Addressed when satisfied.';
+      render();
+    } catch (error) {
+      qs('#pull-feedback-status').textContent = error.message + ' Preview kept; reload if the branch changed, or retry.';
+      button.disabled = false;
+      button.focus();
+    }
+  });
   qs('#make-pull-feedback-fix').addEventListener('click', async () => {
     const comment = current();
     if (!active || !comment?.path || active.detail?.capabilities?.authored !== true) return;
@@ -495,6 +587,7 @@ function bindFeedbackControls(doc, controller, getSelected, getDetail, getLogin)
       const file = await controller.loadFeedbackFile(active.item, comment.path, active.detail.head_sha);
       if (!active || file.head_sha !== active.detail.head_sha || file.path !== comment.path) return;
       active.file = file;
+      clearSuggestion();
       qs('#pull-feedback-file-path').textContent = file.path;
       qs('#pull-feedback-file-content').value = file.content;
       qs('#pull-feedback-commit-message').value = 'fix: address review feedback';
diff --git a/src/gitea_proxy.py b/src/gitea_proxy.py
index a2dc298..6f63648 100644
--- a/src/gitea_proxy.py
+++ b/src/gitea_proxy.py
@@ -3618,6 +3618,20 @@ async def pull_completion_detail(
     }
 
 
+def _single_line_suggestion(body: str, line: object) -> dict | None:
+    if not isinstance(line, int) or line <= 0:
+        return None
+    blocks = re.findall(r"(?ms)^```suggestion[ \t]*\r?\n(.*?)\r?\n```[ \t]*$", body)
+    if len(blocks) != 1:
+        return None
+    content = blocks[0].replace("\r\n", "\n")
+    if not content or "\x00" in content or len(content.encode("utf-8")) > 4096:
+        return None
+    if len(content.splitlines()) > 20:
+        return None
+    return {"line": line, "content": content}
+
+
 def _normalize_review_comments(comments: object) -> list[dict]:
     normalized = []
     for comment in (comments if isinstance(comments, list) else [])[:100]:
@@ -3634,6 +3648,9 @@ def _normalize_review_comments(comments: object) -> list[dict]:
         position = comment.get("new_position") or comment.get("old_position")
         if isinstance(position, int) and position > 0:
             item["line"] = position
+        suggestion = _single_line_suggestion(body, position)
+        if suggestion is not None:
+            item["suggestion"] = suggestion
         normalized.append(item)
         if len(normalized) == 20:
             break
diff --git a/tests/e2e/test_mobile_apply_review_suggestion_release.py b/tests/e2e/test_mobile_apply_review_suggestion_release.py
new file mode 100644
index 0000000..671d7df
--- /dev/null
+++ b/tests/e2e/test_mobile_apply_review_suggestion_release.py
@@ -0,0 +1,103 @@
+from pathlib import Path
+
+import pytest
+
+
+ROOT = Path(__file__).parents[2]
+
+
+@pytest.mark.parametrize("viewport", [(320, 568), (390, 844)])
+def test_mobile_author_previews_and_applies_review_suggestion(viewport):
+    playwright = pytest.importorskip("playwright.sync_api")
+    html = (ROOT / "frontend" / "index.html").read_text()
+    detail = {
+        "state": "open", "merged": False, "head_sha": "abc1234",
+        "capabilities": {"authored": True},
+        "reviewers": [{
+            "review_id": 42, "login": "sam", "status": "changes_requested",
+            "head_sha": "abc1234", "blocking": True, "feedback_state": "loaded",
+            "comments": [{
+                "id": 99, "path": "src/api.py", "line": 2,
+                "body": "Return the typed empty result.\n```suggestion\n    return empty_result()\n```",
+                "suggestion": {"line": 2, "content": "    return empty_result()"},
+            }, {
+                "id": 100, "path": "src/api.py", "line": 3,
+                "body": "Keep the result typed.",
+            }],
+        }],
+        "files": [{"filename": "src/api.py", "status": "modified", "diff_available": True,
+                   "diff_lines": ["@@ -2 +2 @@", "+    return None"]}],
+    }
+
+    with playwright.sync_playwright() as runtime:
+        try:
+            browser = runtime.chromium.launch(headless=True)
+        except Exception as error:
+            pytest.skip(f"Chromium is not installed: {error}")
+        page = browser.new_page(viewport={"width": viewport[0], "height": viewport[1]})
+        page.set_content(html, wait_until="domcontentloaded")
+        page.add_style_tag(path=ROOT / "frontend" / "dashboard.css")
+        page.add_script_tag(path=ROOT / "frontend" / "pull-sheet.js")
+        page.evaluate(
+            """detail => {
+                globalThis.confirm = () => true;
+                globalThis.suggestionCalls = [];
+                globalThis.suggestionItem = {repository:'stackchain/api', number:7, key:'stackchain/api#7'};
+                globalThis.suggestionDetail = detail;
+                globalThis.suggestionController = createPullSheet({fetchJson: async (path, options = {}) => {
+                    suggestionCalls.push({path, options});
+                    if ((options.method || 'GET') === 'GET') return {
+                        path:'src/api.py', head_sha:'abc1234', blob_sha:'blob123',
+                        content:'def lookup():\\n    return None\\n'
+                    };
+                    return {path:'src/api.py', previous_head_sha:'abc1234', head_sha:'def5678', blob_sha:'blob456'};
+                }});
+                document.querySelector('#pull-sheet').classList.add('open');
+                document.querySelector('#pull-review').open = true;
+                document.querySelector('#pull-files').innerHTML = detail.files.map((file, index) =>
+                    createPullSheet.renderFile(file, index, false, value => String(value))
+                ).join('');
+                createPullSheet.bindFeedbackControls(document, suggestionController,
+                    () => suggestionItem, () => suggestionDetail, () => 'alex');
+                createPullSheet.review(detail, null, document);
+            }""",
+            detail,
+        )
+
+        page.locator(".pull-review-feedback summary").click()
+        page.locator('[data-address-review-feedback="42"]').click()
+        assert page.locator("#pull-feedback-file-editor").is_hidden()
+        assert page.locator("#review-pull-feedback-suggestion").is_visible()
+        page.locator("#review-pull-feedback-suggestion").click()
+        page.wait_for_function("suggestionCalls.length === 1")
+        assert page.locator("#pull-feedback-suggestion-preview").is_visible()
+        assert page.locator("#pull-feedback-suggestion-before").text_content() == "    return None"
+        assert page.locator("#pull-feedback-suggestion-after").text_content() == "    return empty_result()"
+        assert page.locator("#pull-feedback-file-editor").is_hidden()
+        page.locator("#next-pull-feedback").click()
+        assert page.locator("#pull-feedback-suggestion-preview").is_hidden()
+        assert page.locator("#review-pull-feedback-suggestion").is_hidden()
+        page.locator("#previous-pull-feedback").click()
+        page.locator("#review-pull-feedback-suggestion").click()
+        page.wait_for_function("suggestionCalls.length === 2")
+        page.locator("#apply-pull-feedback-suggestion").click()
+        page.wait_for_function("suggestionCalls.length === 3")
+        result = page.evaluate("""() => ({
+            calls:suggestionCalls, head:suggestionDetail.head_sha,
+            previewHidden:document.querySelector('#pull-feedback-suggestion-preview').hidden,
+            status:document.querySelector('#pull-feedback-status').textContent,
+            scrollWidth:document.documentElement.scrollWidth,
+            clientWidth:document.documentElement.clientWidth,
+            heights:Array.from(document.querySelectorAll('#pull-feedback-pass button'))
+                .filter(button => button.getClientRects().length > 0).map(button => button.getBoundingClientRect().height),
+        })""")
+        browser.close()
+
+    assert result["scrollWidth"] <= result["clientWidth"]
+    assert min(result["heights"]) >= 44
+    assert result["head"] == "def5678"
+    assert result["previewHidden"] is True
+    assert "suggested change committed" in result["status"].lower()
+    body = result["calls"][2]["options"]["body"]
+    assert '"expected_blob_sha":"blob123"' in body
+    assert '"content":"def lookup():\\n    return empty_result()\\n"' in body
diff --git a/tests/test_pull_api.py b/tests/test_pull_api.py
index c4b809d..4e28098 100644
--- a/tests/test_pull_api.py
+++ b/tests/test_pull_api.py
@@ -875,6 +875,34 @@ def test_review_comments_are_bounded_and_require_a_file_and_body():
     assert all(item["path"] and item["body"] for item in normalized)
 
 
+def test_review_comments_expose_one_bounded_line_suggestion_only():
+    comments = [
+        {
+            "id": 1,
+            "path": "src/api.py",
+            "new_position": 4,
+            "body": "Handle the empty state:\n```suggestion\nreturn empty_result()\n```",
+        },
+        {
+            "id": 2,
+            "path": "src/api.py",
+            "new_position": 7,
+            "body": "Choose one:\n```suggestion\nfirst()\n```\n```suggestion\nsecond()\n```",
+        },
+        {
+            "id": 3,
+            "path": "src/api.py",
+            "body": "No stable line:\n```suggestion\nunsafe()\n```",
+        },
+    ]
+
+    normalized = gitea_proxy._normalize_review_comments(comments)
+
+    assert normalized[0]["suggestion"] == {"line": 4, "content": "return empty_result()"}
+    assert "suggestion" not in normalized[1]
+    assert "suggestion" not in normalized[2]
+
+
 def test_review_feedback_preserves_stable_review_and_comment_identities():
     pull = {"requested_reviewers": []}
     reviews = [{