From e7c501396325603c738f1bf7af6e78095262cb48 Mon Sep 17 00:00:00 2001
From: Your Name <you@example.com>
Date: Sun, 28 Jun 2026 14:44:41 +0800
Subject: [PATCH] fix(ci): use event payload for controlled runtime diff

---
 .gitea/workflows/cd.yaml                   | 28 +++++++++++++++++++++-
 scripts/ci/wait-host-web-build-pressure.sh |  1 +
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/.gitea/workflows/cd.yaml b/.gitea/workflows/cd.yaml
index 5afa3eb4..d38816a5 100644
--- a/.gitea/workflows/cd.yaml
+++ b/.gitea/workflows/cd.yaml
@@ -164,7 +164,33 @@ jobs:
       # pyproject.toml hash 變才重裝，其餘直接 activate (節省 ~6-7 min)
       - name: Run API Tests
         run: |
-          CHANGED_FILES="$(git diff-tree --no-commit-id --name-only -r "${GITHUB_SHA:-HEAD}" 2>/dev/null || git show --format= --name-only --no-renames HEAD)"
+          CHANGED_FILES=""
+          if [ -r "${GITHUB_EVENT_PATH:-}" ]; then
+            CHANGED_FILES="$(python3 - <<'PY'
+          import json
+          import os
+
+          event_path = os.environ.get("GITHUB_EVENT_PATH")
+          files = []
+          with open(event_path, "r", encoding="utf-8") as handle:
+              payload = json.load(handle)
+          for commit in payload.get("commits", []) or []:
+              for key in ("added", "modified", "removed"):
+                  files.extend(commit.get(key, []) or [])
+          for path in dict.fromkeys(files):
+              print(path)
+          PY
+          )"
+          fi
+          if [ -z "$CHANGED_FILES" ]; then
+            BASE_SHA="${{ github.event.before }}"
+            if [ -n "$BASE_SHA" ] && ! printf '%s' "$BASE_SHA" | grep -Eq '^0+$'; then
+              git fetch --no-tags --depth=50 origin "${GITHUB_REF_NAME:-main}" >/dev/null 2>&1 || true
+              if git cat-file -e "${BASE_SHA}^{commit}" 2>/dev/null; then
+                CHANGED_FILES="$(git diff --name-only "$BASE_SHA" "${GITHUB_SHA:-HEAD}")"
+              fi
+            fi
+          fi
           if [ -z "$CHANGED_FILES" ]; then
             CHANGED_FILES="$(git show --format= --name-only --no-renames HEAD)"
           fi
diff --git a/scripts/ci/wait-host-web-build-pressure.sh b/scripts/ci/wait-host-web-build-pressure.sh
index 94bea698..19e09694 100755
--- a/scripts/ci/wait-host-web-build-pressure.sh
+++ b/scripts/ci/wait-host-web-build-pressure.sh
@@ -16,6 +16,7 @@ set -euo pipefail
 # 2026-06-28 Codex: cancel-stale-cd trigger for the pre-guard CD run queue.
 # 2026-06-28 Codex: controlled-runtime CD trigger after API test OOM 137.
 # 2026-06-28 Codex: old fail-closed pressure guard is now warn-only in CD.
+# 2026-06-28 Codex: controlled-runtime diff detection now uses event payload.
 
 ATTEMPTS="${HOST_WEB_BUILD_PRESSURE_ATTEMPTS:-${HOST_WEB_BUILD_PRESSURE_MAX_ATTEMPTS:-60}}"
 SLEEP_SECONDS="${HOST_WEB_BUILD_PRESSURE_SLEEP_SECONDS:-${HOST_WEB_BUILD_PRESSURE_INTERVAL:-10}}"