package app

import (
	"strings"
	"time"
)

func transportBootstrapReplaceClientRoutes(clientID string, next []string, route transportMainRoute) error {
	id := sanitizeID(clientID)
	if id == "" {
		return nil
	}
	st := loadTransportBootstrapState()
	prev := append([]string(nil), st.Clients[id]...)
	next = normalizeBootstrapIPv4List(next)

	nextSet := map[string]struct{}{}
	for _, ip := range next {
		nextSet[ip] = struct{}{}
	}
	for _, ip := range prev {
		if _, keep := nextSet[ip]; keep {
			continue
		}
		if err := transportDeleteBootstrapRoute(ip); err != nil {
			return err
		}
	}
	for _, ip := range next {
		if err := transportReplaceBootstrapRoute(ip, route); err != nil {
			return err
		}
	}

	if len(st.Clients) == 0 {
		st.Clients = map[string][]string{}
	}
	if len(next) == 0 {
		delete(st.Clients, id)
	} else {
		st.Clients[id] = append([]string(nil), next...)
	}
	return saveTransportBootstrapState(st)
}

func transportBootstrapRemoveClientRoutes(clientID string) error {
	id := sanitizeID(clientID)
	if id == "" {
		return nil
	}
	st := loadTransportBootstrapState()
	prev := append([]string(nil), st.Clients[id]...)
	if len(prev) == 0 {
		return nil
	}
	for _, ip := range prev {
		if err := transportDeleteBootstrapRoute(ip); err != nil {
			return err
		}
	}
	delete(st.Clients, id)
	return saveTransportBootstrapState(st)
}

func transportReplaceBootstrapRoute(ip string, route transportMainRoute) error {
	args := []string{"-4", "route", "replace", ip + "/32", "table", routesTableName()}
	if strings.TrimSpace(route.Via) != "" {
		args = append(args, "via", route.Via)
	}
	args = append(args, "dev", route.Dev)
	stdout, stderr, code, err := transportRunCommand(5*time.Second, "ip", args...)
	if err != nil || code != 0 {
		return transportCommandError("ip "+strings.Join(args, " "), stdout, stderr, code, err)
	}
	return nil
}

func transportDeleteBootstrapRoute(ip string) error {
	args := []string{"-4", "route", "del", ip + "/32", "table", routesTableName()}
	stdout, stderr, code, err := transportRunCommand(5*time.Second, "ip", args...)
	if err == nil && code == 0 {
		return nil
	}
	combined := strings.ToLower(strings.TrimSpace(stderr + " " + stdout))
	if strings.Contains(combined, "no such process") || strings.Contains(combined, "cannot find") {
		return nil
	}
	return transportCommandError("ip "+strings.Join(args, " "), stdout, stderr, code, err)
}