package www

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

	"helix-proxy/internal/config"
)

// LoadPage returns HTML for name (e.g. "index.html", "404.html").
// A file in WWW_DIR with the same name overrides the embedded default.
// Placeholders use the form {{KEY}} and are replaced from vars.
func LoadPage(name string, vars map[string]string) []byte {
	wwwDir := config.Resolve("www")
	customPath := filepath.Join(wwwDir, name)

	data, err := os.ReadFile(customPath)
	if err != nil {
		data, err = defaults.ReadFile(name)
		if err != nil {
			return nil
		}
	}

	if len(vars) == 0 {
		return data
	}
	s := string(data)
	for k, v := range vars {
		s = strings.ReplaceAll(s, "{{"+k+"}}", v)
	}
	return []byte(s)
}