package service

import (
	"os"
	"path/filepath"
	"strings"
)

// comfyVenvHome returns the base interpreter directory of the Python venv at
// <comfyDir>/.venv when that directory lives outside comfyDir, "" otherwise.
// uv-created venvs (Comfy-Desktop) ship a redirector python.exe whose real
// interpreter is the pyvenv.cfg "home" tree — typically a sibling of
// COMFY_DIR, which a sandbox/ACL covering COMFY_DIR alone does not reach.
func comfyVenvHome(comfyDir string) string {
	data, err := os.ReadFile(filepath.Join(comfyDir, ".venv", "pyvenv.cfg"))
	if err != nil {
		return ""
	}
	for _, line := range strings.Split(string(data), "\n") {
		k, v, ok := strings.Cut(line, "=")
		if !ok || strings.TrimSpace(k) != "home" {
			continue
		}
		home := strings.TrimSpace(v)
		if home == "" {
			return ""
		}
		if st, err := os.Stat(home); err != nil || !st.IsDir() {
			return ""
		}
		rel, err := filepath.Rel(comfyDir, home)
		if err != nil || rel == ".." || strings.HasPrefix(rel, ".."+string(filepath.Separator)) {
			return home
		}
		return "" // inside comfyDir: already covered by the COMFY_DIR grant
	}
	return ""
}