package main

import (
	"context"
	"crypto/tls"
	"errors"
	"flag"
	"log"
	"net/http"
	"os"
	"os/signal"
	"path/filepath"
	"syscall"
	"time"

	"vetting/internal/api"
	"vetting/internal/config"
	"vetting/internal/db"
	"vetting/internal/events"
	"vetting/internal/httpserver"
	"vetting/internal/janitor"
	"vetting/internal/logs"
	"vetting/internal/model"
	"vetting/internal/notify"
	"vetting/internal/orchestrator"
	"vetting/internal/pxe"
	"vetting/internal/store"
	"vetting/internal/web/templates"
)

func main() {
	configPath := flag.String("config", "deploy/vetting.example.yaml", "path to vetting.yaml")
	flag.Parse()

	cfg, err := config.Load(*configPath)
	if err != nil {
		log.Fatalf("load config: %v", err)
	}

	for _, dir := range []string{
		filepath.Dir(cfg.Database.Path),
		cfg.Artifacts.Dir,
		cfg.Logs.Dir,
	} {
		if err := os.MkdirAll(dir, 0o755); err != nil {
			log.Fatalf("mkdir %s: %v", dir, err)
		}
	}

	conn, err := db.Open(cfg.Database.Path)
	if err != nil {
		log.Fatalf("open db: %v", err)
	}
	defer func() { _ = conn.Close() }()

	hostStore := &store.Hosts{DB: conn}
	runStore := &store.Runs{DB: conn}
	stageStore := &store.Stages{DB: conn}
	artifactStore := &store.Artifacts{DB: conn}
	specDiffStore := &store.SpecDiffs{DB: conn}
	measurementStore := &store.Measurements{DB: conn}

	hub := events.NewHub()

	logHub, err := logs.NewHub(cfg.Logs.Dir, hub)
	if err != nil {
		log.Fatalf("logs hub: %v", err)
	}
	defer logHub.Close()

	runner := &orchestrator.Runner{
		Runs:     runStore,
		Hosts:    hostStore,
		Stages:   stageStore,
		EventHub: hub,
	}

	tiles := &api.TileEnricher{
		Runs:      runStore,
		Artifacts: artifactStore,
		SpecDiffs: specDiffStore,
	}

	// Inject a templ renderer so the Runner can publish tile-refresh
	// fragments via SSE without pulling web/templates into the
	// orchestrator package. The closure enriches the tile with spec-
	// diff count and hold-key path so every tile render shows the
	// same data, whether it came from /events or an initial page load.
	orchestrator.TileRenderer = func(ctx context.Context, host model.Host, latest *model.Run) string {
		return templates.RenderTileString(tiles.Build(ctx, host, latest))
	}
	orchestrator.PipelineRenderer = templates.RenderPipelineString

	notifyReg, err := notify.BuildRegistry(cfg.Notifiers, cfg.Routes)
	if err != nil {
		log.Fatalf("notify: %v", err)
	}

	ui := &api.UI{
		Hosts:     hostStore,
		Runs:      runStore,
		Stages:    stageStore,
		SpecDiffs: specDiffStore,
		Artifacts: artifactStore,
		EventHub:  hub,
		Logs:      logHub,
		Runner:    runner,
		Tiles:     tiles,
		PublicURL: cfg.Server.PublicURL,
	}

	agentAPI := &api.Agent{
		Hosts:           hostStore,
		Runs:            runStore,
		Stages:          stageStore,
		Artifacts:       artifactStore,
		SpecDiffs:       specDiffStore,
		Measurements:    measurementStore,
		Runner:          runner,
		EventHub:        hub,
		Logs:            logHub,
		Notify:          notifyReg,
		ArtifactsDir:    cfg.Artifacts.Dir,
		OrchestratorURL: cfg.PXE.OrchestratorURL,
		PublicURL:       cfg.Server.PublicURL,
		IperfPort:       cfg.Network.IperfPort,
	}
	agentAPI.LiveKernelURL, agentAPI.LiveInitrdURL = pxe.BuildLiveURLs(cfg.PXE.OrchestratorURL)

	dispatcher := orchestrator.NewDispatcher(cfg.Dispatcher.MaxConcurrentRuns, runStore, hostStore, runner, logHub)
	iperfSup := orchestrator.NewIperfSupervisor(cfg.Network.IperfPort)

	janitorSvc := janitor.New(janitor.Config{
		ArtifactRetention: time.Duration(cfg.Artifacts.RetentionDays) * 24 * time.Hour,
		LogRetention:      time.Duration(cfg.Logs.RetentionDays) * 24 * time.Hour,
		Interval:          time.Duration(cfg.Janitor.IntervalMinutes) * time.Minute,
	}, &janitor.StoreAdapter{Runs: runStore, Artifacts: artifactStore, Logs: logHub})

	// Anchor tftp_root and the pxe runtime dir under artifacts.dir's
	// parent (typically /var/lib/vetting), not logs.dir's parent. The
	// production systemd unit's ReadWritePaths=/var/lib/vetting /var/log/vetting
	// sandbox forbids writing outside those trees, so deriving from
	// /var/log/vetting would land us at /var/log/{tftp,pxe} — unwritable.
	stateRoot := filepath.Dir(cfg.Artifacts.Dir)
	tftpRoot := cfg.PXE.TFTPRoot
	if tftpRoot == "" {
		tftpRoot = filepath.Join(stateRoot, "tftp")
	}
	var supervisor *pxe.Supervisor
	if cfg.PXE.Enabled {
		supervisor = pxe.NewSupervisor(pxe.SupervisorConfig{
			Enabled:         true,
			Interface:       cfg.PXE.Interface,
			Subnet:          cfg.PXE.Subnet,
			OrchestratorURL: cfg.PXE.OrchestratorURL,
			RuntimeDir:      filepath.Join(stateRoot, "pxe"),
			TFTPRoot:        tftpRoot,
			LiveDir:         cfg.PXE.LiveDir,
		})
		ui.PXE = supervisor
	}

	router := httpserver.NewRouter(httpserver.Deps{
		UI:            ui,
		Agent:         agentAPI,
		LiveDir:       cfg.PXE.LiveDir,
		AgentAssetDir: cfg.Agent.AssetDir,
	})

	srv := &http.Server{
		Addr:              cfg.Server.Bind,
		Handler:           router,
		ReadHeaderTimeout: 10 * time.Second,
	}
	if cfg.Server.TLS.Enabled {
		srv.TLSConfig = &tls.Config{MinVersion: tls.VersionTLS12}
	}

	shutdown := make(chan os.Signal, 1)
	signal.Notify(shutdown, os.Interrupt, syscall.SIGTERM)

	rootCtx, cancelRoot := context.WithCancel(context.Background())
	defer cancelRoot()

	dispatcher.Start(rootCtx)
	janitorSvc.Start(rootCtx)

	if err := iperfSup.Start(rootCtx); err != nil {
		log.Fatalf("start iperf3: %v", err)
	}

	if supervisor != nil {
		hosts, err := hostStore.List(rootCtx)
		if err != nil {
			log.Fatalf("list hosts for dnsmasq: %v", err)
		}
		if err := supervisor.Start(rootCtx, hosts); err != nil {
			log.Fatalf("start dnsmasq: %v", err)
		}
	}

	go func() {
		log.Printf("vetting listening on %s (tls=%v, db=%s)", cfg.Server.Bind, cfg.Server.TLS.Enabled, cfg.Database.Path)
		var err error
		if cfg.Server.TLS.Enabled {
			err = srv.ListenAndServeTLS(cfg.Server.TLS.CertFile, cfg.Server.TLS.KeyFile)
		} else {
			err = srv.ListenAndServe()
		}
		if err != nil && !errors.Is(err, http.ErrServerClosed) {
			log.Fatalf("server: %v", err)
		}
	}()

	<-shutdown
	log.Printf("shutting down")

	dispatcher.Stop()
	janitorSvc.Stop()
	_ = iperfSup.Shutdown(3 * time.Second)
	if supervisor != nil {
		_ = supervisor.Shutdown(5 * time.Second)
	}

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	if err := srv.Shutdown(ctx); err != nil {
		log.Printf("server shutdown: %v", err)
	}
	_ = hub.Shutdown(ctx)
}