feat: 拆分评审与提交消息提示词并增加 hook 备份与 JSON 输出

- 新增 custom_reviewer_prompt 和 custom_commit_msg_prompt，兼容旧 custom_prompt
- pre-commit hook 安装时备份已有 hook，卸载时恢复
- 支持 --format json 输出评审结果
- diff 发送前自动脱敏敏感信息

cmd/hook.go

@@ -1,19 +1,142 @@
 package cmd
 
 import (
+	"errors"
+	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 
+	"github.com/spf13/cobra"
 	"github.com/unclesam-ly/git-air/internal/git"
 	"github.com/unclesam-ly/git-air/internal/ui"
-	"github.com/spf13/cobra"
 )
 
-const preCommitScript = `#!/bin/sh
-# git-air pre-commit hook
+const (
+	preCommitMarker         = "# git-air-managed-pre-commit-v1"
+	preCommitBackupSuffix   = ".git-air-backup"
+	preCommitBackupFileName = "pre-commit.git-air-backup"
+)
+
+func preCommitScript(bin ...string) string {
+	binPath := "git-air"
+	if len(bin) > 0 && bin[0] != "" {
+		binPath = bin[0]
+	}
+	return fmt.Sprintf(`#!/bin/sh
+%s
 echo "[git-air] 正在执行 Commit 前代码自动化评审..."
-git-air --staged
-`
+"%s" --staged
+git_air_status=$?
+if [ "$git_air_status" -ne 0 ]; then
+  exit "$git_air_status"
+fi
+
+hook_dir=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
+old_hook="$hook_dir/%s"
+if [ -x "$old_hook" ]; then
+	exec "$old_hook" "$@"
+fi
+exit 0
+`, preCommitMarker, binPath, preCommitBackupFileName)
+}
+
+func isGitAirHook(data []byte) bool {
+	content := string(data)
+	return strings.Contains(content, preCommitMarker) ||
+		strings.Contains(content, "# git-air pre-commit hook") ||
+		strings.Contains(content, "git-air --staged")
+}
+
+func installPreCommitHook(hookPath string) error {
+	backupPath := hookPath + preCommitBackupSuffix
+	hookData, hookReadErr := os.ReadFile(hookPath)
+	hookExists := hookReadErr == nil
+	if hookReadErr != nil && !errors.Is(hookReadErr, os.ErrNotExist) {
+		return hookReadErr
+	}
+	// 幂等安装：已经是 git-air 包装 Hook 时直接返回，绝不把自己再次备份。
+	if hookExists && isGitAirHook(hookData) {
+		return nil
+	}
+
+	if _, err := os.Stat(backupPath); err == nil {
+		return fmt.Errorf("检测到已有 git-air 备份文件 %s，请先执行 hook uninstall", backupPath)
+	} else if !errors.Is(err, os.ErrNotExist) {
+		return err
+	}
+
+	if hookExists {
+		// 保留原 Hook：先移动为备份，再安装包装 Hook。写入失败时尝试恢复。
+		if err := os.Rename(hookPath, backupPath); err != nil {
+			return fmt.Errorf("备份已有 pre-commit Hook 失败: %w", err)
+		}
+	}
+
+	binPath := "git-air"
+	if exe, err := os.Executable(); err == nil && exe != "" {
+		binPath = exe
+	}
+
+	if err := os.WriteFile(hookPath, []byte(preCommitScript(binPath)), 0755); err != nil {
+		if hookExists {
+			_ = os.Remove(hookPath)
+			_ = os.Rename(backupPath, hookPath)
+		}
+		return fmt.Errorf("写入 git-air pre-commit Hook 失败: %w", err)
+	}
+	return nil
+}
+
+func uninstallPreCommitHook(hookPath string) error {
+	data, err := os.ReadFile(hookPath)
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			return fmt.Errorf("当前仓库没有 git-air pre-commit Hook")
+		}
+		return err
+	}
+	if !isGitAirHook(data) {
+		return fmt.Errorf("当前 pre-commit Hook 不是由 git-air 管理，已保留原文件")
+	}
+
+	backupPath := hookPath + preCommitBackupSuffix
+	if _, err := os.Stat(backupPath); err == nil {
+		return restoreOriginalHook(hookPath, backupPath)
+	} else if !errors.Is(err, os.ErrNotExist) {
+		return err
+	}
+
+	return os.Remove(hookPath)
+}
+
+// restoreOriginalHook 恢复备份 Hook。
+// POSIX 系统优先使用 Rename 的原子替换；Windows 目标文件存在时 Rename 可能失败，
+// 此时先把包装 Hook 移到临时路径，恢复失败则尝试回滚，避免先删除导致数据丢失。
+func restoreOriginalHook(hookPath, backupPath string) error {
+	if err := os.Rename(backupPath, hookPath); err == nil {
+		return nil
+	}
+
+	tempPath := hookPath + ".git-air-restore-temp"
+	if _, err := os.Stat(tempPath); err == nil {
+		return fmt.Errorf("恢复原 pre-commit Hook 失败：临时文件已存在 %s", tempPath)
+	} else if !errors.Is(err, os.ErrNotExist) {
+		return err
+	}
+
+	if err := os.Rename(hookPath, tempPath); err != nil {
+		return fmt.Errorf("暂存 git-air Hook 失败: %w", err)
+	}
+	if err := os.Rename(backupPath, hookPath); err != nil {
+		_ = os.Rename(tempPath, hookPath)
+		return fmt.Errorf("恢复原 pre-commit Hook 失败: %w", err)
+	}
+	if err := os.Remove(tempPath); err != nil {
+		return fmt.Errorf("清理临时 Hook 文件失败: %w", err)
+	}
+	return nil
+}
 
 var hookCmd = &cobra.Command{
 	Use:   "hook",
@@ -22,25 +145,30 @@ var hookCmd = &cobra.Command{
 
 var hookInstallCmd = &cobra.Command{
 	Use:   "install",
-	Short: "在当前仓库一键安装 pre-commit 钩子",
+	Short: "在当前仓库安装 pre-commit 钩子并保留已有 Hook",
 	Run: func(cmd *cobra.Command, args []string) {
 		repoRoot, err := git.GetRepoRoot(cmd.Context())
 		if err != nil {
 			ui.PrintError("请在 Git 仓库根目录下执行此命令")
 			return
 		}
-		hookPath := filepath.Join(repoRoot, ".git", "hooks", "pre-commit")
-		if err := os.WriteFile(hookPath, []byte(preCommitScript), 0755); err != nil {
-			ui.PrintError("写入 hook 文件失败: %v", err)
+		hooksDir := filepath.Join(repoRoot, ".git", "hooks")
+		if err := os.MkdirAll(hooksDir, 0755); err != nil {
+			ui.PrintError("创建 hooks 目录失败: %v", err)
 			return
 		}
-		ui.PrintSuccess("已成功安装 pre-commit 钩子！每次执行 git commit 时将自动触发评审。")
+		hookPath := filepath.Join(hooksDir, "pre-commit")
+		if err := installPreCommitHook(hookPath); err != nil {
+			ui.PrintError("安装 Hook 失败: %v", err)
+			return
+		}
+		ui.PrintSuccess("已安装 git-air Hook；已有 Hook 已保存在 pre-commit.git-air-backup，提交通过后会继续执行。")
 	},
 }
 
 var hookUninstallCmd = &cobra.Command{
 	Use:   "uninstall",
-	Short: "移除当前仓库的 pre-commit 钩子",
+	Short: "移除 git-air Hook 并恢复已有 Hook",
 	Run: func(cmd *cobra.Command, args []string) {
 		repoRoot, err := git.GetRepoRoot(cmd.Context())
 		if err != nil {
@@ -48,8 +176,11 @@ var hookUninstallCmd = &cobra.Command{
 			return
 		}
 		hookPath := filepath.Join(repoRoot, ".git", "hooks", "pre-commit")
-		_ = os.Remove(hookPath)
-		ui.PrintSuccess("已成功卸载 pre-commit 钩子！")
+		if err := uninstallPreCommitHook(hookPath); err != nil {
+			ui.PrintError("卸载 Hook 失败: %v", err)
+			return
+		}
+		ui.PrintSuccess("已卸载 git-air Hook；如原来存在 Hook，已恢复原文件。")
 	},
 }