// Copyright 2025, IPng Networks GmbH, Pim van Pelt <pim@ipng.ch>

package main

import (
	"flag"
	"log"
	"os"
	"os/signal"
	"syscall"

	"govpp-snmp-agentx/agentx"
	"govpp-snmp-agentx/config"
	"govpp-snmp-agentx/ifmib"
	"govpp-snmp-agentx/logger"
	"govpp-snmp-agentx/vpp"
)

const Version = "1.2.3-1"

func main() {
	debug := flag.Bool("debug", false, "Enable debug logging")
	vppcfg := flag.String("vppcfg", "", "VPP configuration YAML file to read interface descriptions from")
	flag.Parse()

	// Set global debug flag
	config.Debug = *debug

	// Log startup message with version
	logger.Printf("Starting govpp-snmp-agentx version %s", Version)

	// Create the interface MIB
	interfaceMIB := ifmib.NewInterfaceMIB()

	// Load VPP config if specified
	if *vppcfg != "" {
		if err := interfaceMIB.LoadVPPConfig(*vppcfg); err != nil {
			logger.Printf("Warning: Failed to load VPP config from %s: %v", *vppcfg, err)
			logger.Printf("Continuing without VPP config file...")
		}
	}

	// Start AgentX routine
	if err := agentx.StartAgentXRoutine(interfaceMIB); err != nil {
		log.Fatalf("Failed to start AgentX: %v", err)
	}

	// Create VPP client and managers
	vppClient := &vpp.VPPClient{}
	interfaceManager := vpp.NewInterfaceManager(vppClient)
	statsManager := vpp.NewStatsManager(vppClient, interfaceManager)

	// Set up interface event callback to update interface details
	interfaceManager.SetEventCallback(interfaceMIB.UpdateInterfaceDetails)

	// Set up stats callback to update MIB
	statsManager.SetStatsCallback(interfaceMIB.UpdateStats)

	// Start VPP stats routine
	statsManager.StartStatsRoutine()

	// Start interface event monitoring (handles reconnections automatically)
	interfaceManager.StartEventMonitoring()

	// Set up signal handling for graceful shutdown
	sigChan := make(chan os.Signal, 1)
	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)

	// Wait for shutdown signal
	<-sigChan
	logger.Printf("Shutting down...")

	// Stop stats routine and interface monitoring, then disconnect
	statsManager.StopStatsRoutine()
	interfaceManager.StopEventMonitoring()
	vppClient.Disconnect()

	// Flush any buffered log entries
	logger.Sync()
}