package git

import (
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
)

const hookDelegateScriptBody = `# AUTO GENERATED BY MUGIT, DO NOT MODIFY
data=$(cat)
exitcodes=""
hookname=$(basename "$0")
git_dir="${GIT_DIR:-$(dirname "$0")/..}"

for hook in "${git_dir}/hooks/${hookname}.d"/*; do
  test -x "${hook}" && test -f "${hook}" || continue
  echo "${data}" | "${hook}" "$@"
  exitcodes="${exitcodes} $?"
done

for i in ${exitcodes}; do
  [ ${i} -eq 0 ] || exit ${i}
done
`

var serverHookNames = []string{"pre-receive", "post-receive", "post-update", "update"}

func hookDelegateScript() (string, error) {
	bashPath, err := exec.LookPath("bash")
	if err != nil {
		return "", fmt.Errorf("failed to locate bash: %w", err)
	}
	return fmt.Sprintf("#!%s\n%s", bashPath, hookDelegateScriptBody), nil
}

// SetupHooks installs default server-side hook delegates for this repository.
func (g *Repo) SetupHooks() error {
	delegateScript, err := hookDelegateScript()
	if err != nil {
		return err
	}

	for _, hook := range serverHookNames {
		hookDir := filepath.Join(g.path, "hooks", hook+".d")
		if err := os.MkdirAll(hookDir, 0o755); err != nil {
			return fmt.Errorf("failed to create %s: %w", hookDir, err)
		}

		delegatePath := filepath.Join(g.path, "hooks", hook)
		if err := os.WriteFile(delegatePath, []byte(delegateScript), 0o755); err != nil {
			return fmt.Errorf("failed to write hook delegate %s: %w", delegatePath, err)
		}
	}

	return nil
}