package app

import (
	"fmt"
	"os"
	"strings"
)

// ---------------------------------------------------------------------
// routes systemd unit name resolution
// ---------------------------------------------------------------------

// EN: Resolve routes service/timer unit names from preferred/active iface.
// EN: Env overrides still have top priority for custom deployments.
// RU: Вычисление имен unit для routes service/timer по preferred/active iface.
// RU: Для кастомных окружений сохраняется приоритет переменных окружения.

func resolveRoutesUnitIface() (string, string) {
	st := loadTrafficModeState()
	if pref := normalizePreferredIface(st.PreferredIface); pref != "" {
		return pref, "preferred"
	}
	if statusIface := statusIfaceFromFile(); statusIface != "" && statusIface != "-" {
		return statusIface, "status"
	}
	if active, reason := resolveTrafficIface(""); active != "" {
		return active, reason
	}
	return "", "iface-not-found"
}

func routesServiceUnitName() string {
	if forced := strings.TrimSpace(os.Getenv(routesServiceEnv)); forced != "" {
		return forced
	}
	iface, _ := resolveRoutesUnitIface()
	if iface == "" {
		return ""
	}
	return fmt.Sprintf(routesServiceTemplate, iface)
}

func routesTimerUnitName() string {
	if forced := strings.TrimSpace(os.Getenv(routesTimerEnv)); forced != "" {
		return forced
	}
	iface, _ := resolveRoutesUnitIface()
	if iface == "" {
		return ""
	}
	return fmt.Sprintf(routesTimerTemplate, iface)
}