//go:build windows

package winsvc

import (
	"fmt"
	"log"
	"time"

	"github.com/fleetforge/forge-agent/internal/agent"
	"github.com/fleetforge/forge-agent/internal/config"
	"golang.org/x/sys/windows/svc"
	"golang.org/x/sys/windows/svc/eventlog"
)

const ServiceName = "FleetForgeAgent"
const ServiceDisplayName = "Fleet Forge Agent"
const ServiceDescription = "Fleet Forge endpoint management agent."

type agentService struct {
	cfg *config.Config
}

func (s *agentService) Execute(args []string, r <-chan svc.ChangeRequest, status chan<- svc.Status) (bool, uint32) {
	status <- svc.Status{State: svc.StartPending, Accepts: svc.AcceptStop | svc.AcceptShutdown}

	elog, err := eventlog.Open(ServiceName)
	if err == nil {
		defer elog.Close()
		elog.Info(1, "Fleet Forge Agent service starting")
	}

	a := agent.New(s.cfg)

	done := make(chan error, 1)
	go func() {
		done <- a.Run()
	}()

	status <- svc.Status{State: svc.Running, Accepts: svc.AcceptStop | svc.AcceptShutdown}

	for {
		select {
		case err := <-done:
			if err != nil {
				log.Printf("[service] Agent stopped with error: %v", err)
				if elog != nil {
					elog.Error(1, fmt.Sprintf("Agent stopped: %v", err))
				}
			}
			return false, 0

		case c := <-r:
			switch c.Cmd {
			case svc.Stop, svc.Shutdown:
				log.Println("[service] Stop/Shutdown received")
				status <- svc.Status{State: svc.StopPending}
				return false, 0
			case svc.Interrogate:
				status <- c.CurrentStatus
			}

		case <-time.After(5 * time.Second):
		}
	}
}

func RunAsService() error {
	cfg, err := config.Load()
	if err != nil {
		return fmt.Errorf("failed to load config: %w", err)
	}

	svcInst := &agentService{cfg: cfg}
	return svc.Run(ServiceName, svcInst)
}