feat: improve cli setup flow

src/infra/git-commit.ts

@@ -0,0 +1,76 @@
+import fs from "node:fs";
+import path from "node:path";
+
+const formatCommit = (value?: string | null) => {
+  if (!value) return null;
+  const trimmed = value.trim();
+  if (!trimmed) return null;
+  return trimmed.length > 7 ? trimmed.slice(0, 7) : trimmed;
+};
+
+const resolveGitHead = (startDir: string) => {
+  let current = startDir;
+  for (let i = 0; i < 12; i += 1) {
+    const gitPath = path.join(current, ".git");
+    try {
+      const stat = fs.statSync(gitPath);
+      if (stat.isDirectory()) {
+        return path.join(gitPath, "HEAD");
+      }
+      if (stat.isFile()) {
+        const raw = fs.readFileSync(gitPath, "utf-8");
+        const match = raw.match(/gitdir:\s*(.+)/i);
+        if (match?.[1]) {
+          const resolved = path.resolve(current, match[1].trim());
+          return path.join(resolved, "HEAD");
+        }
+      }
+    } catch {
+      // ignore missing .git at this level
+    }
+    const parent = path.dirname(current);
+    if (parent === current) break;
+    current = parent;
+  }
+  return null;
+};
+
+let cachedCommit: string | null | undefined;
+
+export const resolveCommitHash = (options: {
+  cwd?: string;
+  env?: NodeJS.ProcessEnv;
+} = {}) => {
+  if (cachedCommit !== undefined) return cachedCommit;
+  const env = options.env ?? process.env;
+  const envCommit = env.GIT_COMMIT?.trim() || env.GIT_SHA?.trim();
+  const normalized = formatCommit(envCommit);
+  if (normalized) {
+    cachedCommit = normalized;
+    return cachedCommit;
+  }
+  try {
+    const headPath = resolveGitHead(options.cwd ?? process.cwd());
+    if (!headPath) {
+      cachedCommit = null;
+      return cachedCommit;
+    }
+    const head = fs.readFileSync(headPath, "utf-8").trim();
+    if (!head) {
+      cachedCommit = null;
+      return cachedCommit;
+    }
+    if (head.startsWith("ref:")) {
+      const ref = head.replace(/^ref:\s*/i, "").trim();
+      const refPath = path.resolve(path.dirname(headPath), ref);
+      const refHash = fs.readFileSync(refPath, "utf-8").trim();
+      cachedCommit = formatCommit(refHash);
+      return cachedCommit;
+    }
+    cachedCommit = formatCommit(head);
+    return cachedCommit;
+  } catch {
+    cachedCommit = null;
+    return cachedCommit;
+  }
+};