bee/audit/internal/webui/server.go

package webui

import (
	"bufio"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"log/slog"
	"mime"
	"net"
	"net/http"
	"os"
	"path/filepath"
	"runtime/debug"
	"strings"
	"sync"
	"time"

	"bee/audit/internal/app"
	"bee/audit/internal/platform"
	"bee/audit/internal/runtimeenv"
	"reanimator/chart/viewer"
	"reanimator/chart/web"
)

const defaultTitle = "Bee Hardware Audit"

func init() {
	// On some LiveCD ramdisk environments, /usr/share/mime/globs2 exists but
	// causes an I/O error mid-read. Go's mime package panics (not errors) in
	// that case, crashing the first HTTP goroutine that serves a static file.
	// Pre-trigger initialization here with recover so subsequent calls are safe.
	func() {
		defer func() { recover() }() //nolint:errcheck
		mime.TypeByExtension(".gz")
	}()
}

// HandlerOptions configures the web UI handler.
type HandlerOptions struct {
	Title       string
	BuildLabel  string
	AuditPath   string
	ExportDir   string
	App         *app.App
	RuntimeMode runtimeenv.Mode
}

// metricsRing holds a rolling window of live metric samples.
type metricsRing struct {
	mu    sync.Mutex
	vals  []float64
	times []time.Time
	size  int
}

func newMetricsRing(size int) *metricsRing {
	return &metricsRing{size: size, vals: make([]float64, 0, size), times: make([]time.Time, 0, size)}
}

func (r *metricsRing) push(v float64) {
	r.mu.Lock()
	defer r.mu.Unlock()
	if len(r.vals) >= r.size {
		r.vals = r.vals[1:]
		r.times = r.times[1:]
	}
	r.vals = append(r.vals, v)
	r.times = append(r.times, time.Now())
}

func (r *metricsRing) snapshot() ([]float64, []string) {
	r.mu.Lock()
	defer r.mu.Unlock()
	v := make([]float64, len(r.vals))
	copy(v, r.vals)
	labels := make([]string, len(r.times))
	if len(r.times) == 0 {
		return v, labels
	}
	sameDay := timestampsSameLocalDay(r.times)
	for i, t := range r.times {
		labels[i] = formatTimelineLabel(t.Local(), sameDay)
	}
	return v, labels
}

func (r *metricsRing) latest() (float64, bool) {
	r.mu.Lock()
	defer r.mu.Unlock()
	if len(r.vals) == 0 {
		return 0, false
	}
	return r.vals[len(r.vals)-1], true
}

func timestampsSameLocalDay(times []time.Time) bool {
	if len(times) == 0 {
		return true
	}
	first := times[0].Local()
	for _, t := range times[1:] {
		local := t.Local()
		if local.Year() != first.Year() || local.YearDay() != first.YearDay() {
			return false
		}
	}
	return true
}

func formatTimelineLabel(ts time.Time, sameDay bool) string {
	if sameDay {
		return ts.Format("15:04")
	}
	return ts.Format("01-02 15:04")
}

// gpuRings holds per-GPU ring buffers.
type gpuRings struct {
	Temp    *metricsRing
	Util    *metricsRing
	MemUtil *metricsRing
	Power   *metricsRing
}

type namedMetricsRing struct {
	Name string
	Ring *metricsRing
}

// metricsChartWindow is the number of samples kept in the live ring buffer.
// At metricsCollectInterval = 5 s this covers 30 minutes of live history.
const metricsChartWindow = 360

// metricsDownsampleAge is the age after which old metrics rows are downsampled
// to 1 sample per minute. Data fresher than this is kept at full resolution.
const metricsDownsampleAge = 2 * time.Hour

// metricsRetainWindow is the total retention period for metrics rows.
// Rows older than this are deleted entirely by the background compactor.
const metricsRetainWindow = 48 * time.Hour

var metricsCollectInterval = 5 * time.Second

// pendingNetChange tracks a network state change awaiting confirmation.
type pendingNetChange struct {
	snapshot platform.NetworkSnapshot
	deadline time.Time
	timer    *time.Timer
	mu       sync.Mutex
}

// handler is the HTTP handler for the web UI.
type handler struct {
	opts HandlerOptions
	mux  *http.ServeMux
	// server rings
	ringCPULoad      *metricsRing
	ringMemLoad      *metricsRing
	ringPower        *metricsRing
	ringFans         []*metricsRing
	fanNames         []string
	cpuTempRings     []*namedMetricsRing
	ambientTempRings []*namedMetricsRing
	// per-GPU rings (index = GPU index)
	gpuRings []*gpuRings
	ringsMu  sync.Mutex
	latestMu sync.RWMutex
	latest   *platform.LiveMetricSample
	// metrics persistence (nil if DB unavailable)
	metricsDB *MetricsDB
	// pending network change (rollback on timeout)
	pendingNet   *pendingNetChange
	pendingNetMu sync.Mutex
	// kmsg hardware error watcher
	kmsg *kmsgWatcher
}

// NewHandler creates the HTTP mux with all routes.
func NewHandler(opts HandlerOptions) http.Handler {
	if strings.TrimSpace(opts.Title) == "" {
		opts.Title = defaultTitle
	}
	if strings.TrimSpace(opts.ExportDir) == "" {
		opts.ExportDir = app.DefaultExportDir
	}
	if opts.RuntimeMode == "" {
		opts.RuntimeMode = runtimeenv.ModeAuto
	}

	h := &handler{
		opts:        opts,
		ringCPULoad: newMetricsRing(120),
		ringMemLoad: newMetricsRing(120),
		ringPower:   newMetricsRing(120),
	}

	// Open metrics DB and pre-fill ring buffers from history.
	if db, err := openMetricsDB(metricsDBPath); err == nil {
		h.metricsDB = db
		if samples, err := db.LoadRecent(metricsChartWindow); err == nil {
			for _, s := range samples {
				h.feedRings(s)
			}
			if len(samples) > 0 {
				h.setLatestMetric(samples[len(samples)-1])
			}
		} else {
			slog.Warn("metrics history unavailable", "path", metricsDBPath, "err", err)
		}
	} else {
		slog.Warn("metrics db disabled", "path", metricsDBPath, "err", err)
	}
	h.startMetricsCollector()

	// Start kmsg hardware error watcher if the app (and its status DB) is available.
	if opts.App != nil {
		h.kmsg = newKmsgWatcher(opts.App.StatusDB)
		h.kmsg.start()
		globalQueue.kmsgWatcher = h.kmsg

		// Start periodic health poller for components that don't emit kernel log events (e.g. PSU).
		if opts.App.StatusDB != nil {
			newHealthPoller(opts.App.StatusDB).start()
		}
	}

	globalQueue.startWorker(&opts)
	mux := http.NewServeMux()

	// ── Infrastructure ──────────────────────────────────────────────────────
	mux.HandleFunc("GET /healthz", h.handleHealthz)
	mux.HandleFunc("GET /api/ready", h.handleReady)
	mux.HandleFunc("GET /loading", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Cache-Control", "no-store")
		w.Header().Set("Content-Type", "text/html; charset=utf-8")
		_, _ = w.Write([]byte(loadingPageHTML))
	})

	// ── Existing read-only endpoints (preserved for compatibility) ──────────
	mux.HandleFunc("GET /audit.json", h.handleAuditJSON)
	mux.HandleFunc("GET /runtime-health.json", h.handleRuntimeHealthJSON)
	mux.HandleFunc("GET /export/support.tar.gz", h.handleSupportBundleDownload)
	mux.HandleFunc("GET /export/file", h.handleExportFile)
	mux.HandleFunc("GET /export/", h.handleExportIndex)
	mux.HandleFunc("GET /viewer", h.handleViewer)

	// ── API ──────────────────────────────────────────────────────────────────
	// Audit
	mux.HandleFunc("POST /api/audit/run", h.handleAPIAuditRun)
	mux.HandleFunc("GET /api/audit/stream", h.handleAPIAuditStream)

	// SAT
	mux.HandleFunc("POST /api/sat/nvidia/run", h.handleAPISATRun("nvidia"))
	mux.HandleFunc("POST /api/sat/nvidia-targeted-stress/run", h.handleAPISATRun("nvidia-targeted-stress"))
	mux.HandleFunc("POST /api/sat/nvidia-compute/run", h.handleAPISATRun("nvidia-compute"))
	mux.HandleFunc("POST /api/sat/nvidia-targeted-power/run", h.handleAPISATRun("nvidia-targeted-power"))
	mux.HandleFunc("POST /api/sat/nvidia-pulse/run", h.handleAPISATRun("nvidia-pulse"))
	mux.HandleFunc("POST /api/sat/nvidia-interconnect/run", h.handleAPISATRun("nvidia-interconnect"))
	mux.HandleFunc("POST /api/sat/nvidia-bandwidth/run", h.handleAPISATRun("nvidia-bandwidth"))
	mux.HandleFunc("POST /api/sat/nvidia-stress/run", h.handleAPISATRun("nvidia-stress"))
	mux.HandleFunc("POST /api/sat/memory/run", h.handleAPISATRun("memory"))
	mux.HandleFunc("POST /api/sat/storage/run", h.handleAPISATRun("storage"))
	mux.HandleFunc("POST /api/sat/tpm/run", h.handleAPISATRun("tpm"))
	mux.HandleFunc("POST /api/sat/nvidia-config/run", h.handleAPISATRun("nvidia-config"))
	mux.HandleFunc("POST /api/sat/cpu/run", h.handleAPISATRun("cpu"))
	mux.HandleFunc("POST /api/sat/amd/run", h.handleAPISATRun("amd"))
	mux.HandleFunc("POST /api/sat/amd-mem/run", h.handleAPISATRun("amd-mem"))
	mux.HandleFunc("POST /api/sat/amd-bandwidth/run", h.handleAPISATRun("amd-bandwidth"))
	mux.HandleFunc("POST /api/sat/amd-stress/run", h.handleAPISATRun("amd-stress"))
	mux.HandleFunc("POST /api/sat/memory-stress/run", h.handleAPISATRun("memory-stress"))
	mux.HandleFunc("POST /api/sat/sat-stress/run", h.handleAPISATRun("sat-stress"))
	mux.HandleFunc("POST /api/sat/platform-stress/run", h.handleAPISATRun("platform-stress"))
	mux.HandleFunc("POST /api/sat/fan/run", h.handleAPISATRun("fan"))
	mux.HandleFunc("POST /api/sat/run-all", h.handleAPISATRunAll)
	mux.HandleFunc("GET /api/sat/stream", h.handleAPISATStream)
	mux.HandleFunc("POST /api/sat/abort", h.handleAPISATAbort)
	mux.HandleFunc("POST /api/bee-bench/nvidia/perf/run", h.handleAPIBenchmarkNvidiaRunKind("nvidia-bench-perf"))
	mux.HandleFunc("POST /api/bee-bench/nvidia/power/run", h.handleAPIBenchmarkNvidiaRunKind("nvidia-bench-power"))
	mux.HandleFunc("POST /api/bee-bench/nvidia/autotune/run", h.handleAPIBenchmarkAutotuneRun())
	mux.HandleFunc("GET /api/scenario/list", h.handleAPIScenarioList)
	mux.HandleFunc("POST /api/scenario/run", h.handleAPIScenarioRun)
	mux.HandleFunc("GET /api/bee-bench/nvidia/autotune/status", h.handleAPIBenchmarkAutotuneStatus)
	mux.HandleFunc("GET /api/benchmark/results", h.handleAPIBenchmarkResults)

	// Tasks
	mux.HandleFunc("GET /api/tasks", h.handleAPITasksList)
	mux.HandleFunc("POST /api/tasks/cancel-all", h.handleAPITasksCancelAll)
	mux.HandleFunc("POST /api/tasks/kill-workers", h.handleAPITasksKillWorkers)
	mux.HandleFunc("POST /api/tasks/{id}/cancel", h.handleAPITasksCancel)
	mux.HandleFunc("POST /api/tasks/{id}/priority", h.handleAPITasksPriority)
	mux.HandleFunc("GET /api/tasks/{id}/stream", h.handleAPITasksStream)
	mux.HandleFunc("GET /api/tasks/{id}/charts", h.handleAPITaskChartsIndex)
	mux.HandleFunc("GET /api/tasks/{id}/chart/", h.handleAPITaskChartSVG)
	mux.HandleFunc("GET /tasks/{id}", h.handleTaskPage)

	// Services
	mux.HandleFunc("GET /api/services", h.handleAPIServicesList)
	mux.HandleFunc("POST /api/services/action", h.handleAPIServicesAction)

	// Network
	mux.HandleFunc("GET /api/network", h.handleAPINetworkStatus)
	mux.HandleFunc("POST /api/network/dhcp", h.handleAPINetworkDHCP)
	mux.HandleFunc("POST /api/network/static", h.handleAPINetworkStatic)
	mux.HandleFunc("POST /api/network/toggle", h.handleAPINetworkToggle)
	mux.HandleFunc("POST /api/network/confirm", h.handleAPINetworkConfirm)
	mux.HandleFunc("POST /api/network/rollback", h.handleAPINetworkRollback)

	// Export
	mux.HandleFunc("GET /api/export/list", h.handleAPIExportList)
	mux.HandleFunc("GET /api/export/usb", h.handleAPIExportUSBTargets)
	mux.HandleFunc("GET /api/blackbox/status", h.handleAPIBlackboxStatus)
	mux.HandleFunc("POST /api/blackbox/enable", h.handleAPIBlackboxEnable)
	mux.HandleFunc("POST /api/blackbox/disable", h.handleAPIBlackboxDisable)

	// Tools
	mux.HandleFunc("GET /api/tools/check", h.handleAPIToolsCheck)
	mux.HandleFunc("GET /api/tools/nvme-formats", h.handleAPINVMeFormats)
	mux.HandleFunc("POST /api/tools/nvme-format/run", h.handleAPINVMeFormatRun)
	mux.HandleFunc("GET /api/tools/saa-dmi", h.handleAPISAADMIRead)
	mux.HandleFunc("POST /api/tools/saa-dmi/write", h.handleAPISAADMIWrite)
	mux.HandleFunc("GET /api/tools/ipmi-fru", h.handleAPIIPMIFRURead)
	mux.HandleFunc("POST /api/tools/ipmi-fru/write", h.handleAPIIPMIFRUWrite)
	mux.HandleFunc("GET /api/tools/huawei-elabel", h.handleAPIHuaweiElabelRead)
	mux.HandleFunc("POST /api/tools/huawei-elabel/write", h.handleAPIHuaweiElabelWrite)
	mux.HandleFunc("GET /api/tools/raid/status", h.handleAPIRAIDStatus)
	mux.HandleFunc("POST /api/tools/raid/foreign", h.handleAPIRAIDForeignAction)
	mux.HandleFunc("POST /api/tools/raid/create-mirror", h.handleAPIRAIDCreateMirror)
	mux.HandleFunc("POST /api/tools/raid/prepare-drive", h.handleAPIRAIDPrepareDrive)

	// GPU presence / tools
	mux.HandleFunc("GET /api/gpu/presence", h.handleAPIGPUPresence)
	mux.HandleFunc("GET /api/gpu/nvidia", h.handleAPIGNVIDIAGPUs)
	mux.HandleFunc("GET /api/gpu/nvidia-status", h.handleAPIGNVIDIAGPUStatuses)
	mux.HandleFunc("POST /api/gpu/nvidia-reset", h.handleAPIGNVIDIAReset)
	mux.HandleFunc("GET /api/gpu/nvidia-settings", h.handleAPIGNVIDIAGPUSettings)
	mux.HandleFunc("POST /api/gpu/nvidia-ecc", h.handleAPIGNVIDIASetECC)
	mux.HandleFunc("POST /api/gpu/nvidia-mig", h.handleAPIGNVIDIASetMIG)
	mux.HandleFunc("POST /api/gpu/nvidia-cc", h.handleAPIGNVIDIASetCCMode)
	mux.HandleFunc("POST /api/gpu/nvidia-power-limit", h.handleAPIGNVIDIASetPowerLimit)
	mux.HandleFunc("POST /api/gpu/nvidia-reset-defaults", h.handleAPIGNVIDIAResetDefaults)
	mux.HandleFunc("GET /api/gpu/tools", h.handleAPIGPUTools)

	// System
	mux.HandleFunc("GET /api/system/ram-status", h.handleAPIRAMStatus)
	mux.HandleFunc("POST /api/system/install-to-ram", h.handleAPIInstallToRAM)
	mux.HandleFunc("POST /api/system/reboot", h.handleAPISystemReboot)
	mux.HandleFunc("POST /api/system/shutdown", h.handleAPISystemShutdown)
	mux.HandleFunc("GET /api/system/time", h.handleAPISystemTime)
	mux.HandleFunc("POST /api/system/time-sync", h.handleAPISystemTimeSync)

	// Preflight
	mux.HandleFunc("GET /api/preflight", h.handleAPIPreflight)

	// Install
	mux.HandleFunc("GET /api/install/disks", h.handleAPIInstallDisks)
	mux.HandleFunc("POST /api/install/run", h.handleAPIInstallRun)

	// Hardware component detail (fragment for modal in Hardware Summary card)
	mux.HandleFunc("GET /api/hardware-summary", h.handleAPIHardwareSummary)
	mux.HandleFunc("GET /api/components/{type}", h.handleAPIComponentDetail)

	// Metrics — SSE stream of live sensor data + server-side SVG charts + CSV export
	mux.HandleFunc("GET /api/metrics/stream", h.handleAPIMetricsStream)
	mux.HandleFunc("GET /api/metrics/latest", h.handleAPIMetricsLatest)
	mux.HandleFunc("GET /api/metrics/chart/", h.handleMetricsChartSVG)
	mux.HandleFunc("GET /api/metrics/export.csv", h.handleAPIMetricsExportCSV)

	// Reanimator chart static assets (viewer template expects /static/*)
	mux.Handle("GET /static/", http.StripPrefix("/static/", web.Static()))

	// ── Pages ────────────────────────────────────────────────────────────────
	mux.HandleFunc("GET /", h.handlePage)

	h.mux = mux
	return recoverMiddleware(mux)
}

func (h *handler) startMetricsCollector() {
	goRecoverLoop("metrics collector", 2*time.Second, func() {
		ticker := time.NewTicker(metricsCollectInterval)
		defer ticker.Stop()
		pruneTicker := time.NewTicker(time.Hour)
		defer pruneTicker.Stop()
		for {
			select {
			case <-ticker.C:
				sample := platform.SampleLiveMetrics()
				if h.metricsDB != nil {
					_ = h.metricsDB.Write(sample)
				}
				h.feedRings(sample)
				h.setLatestMetric(sample)
			case <-pruneTicker.C:
				if h.metricsDB != nil {
					_ = h.metricsDB.Downsample(metricsDownsampleAge, metricsRetainWindow)
					_ = h.metricsDB.Prune(metricsRetainWindow)
				}
			}
		}
	})
}

func (h *handler) setLatestMetric(sample platform.LiveMetricSample) {
	h.latestMu.Lock()
	defer h.latestMu.Unlock()
	cp := sample
	h.latest = &cp
}

func (h *handler) latestMetric() (platform.LiveMetricSample, bool) {
	h.latestMu.RLock()
	defer h.latestMu.RUnlock()
	if h.latest == nil {
		return platform.LiveMetricSample{}, false
	}
	return *h.latest, true
}

// ListenAndServe starts the HTTP server.
func ListenAndServe(addr string, opts HandlerOptions) error {
	srv := &http.Server{
		Addr:              addr,
		Handler:           NewHandler(opts),
		ReadHeaderTimeout: 5 * time.Second,
		ReadTimeout:       30 * time.Second,
		IdleTimeout:       2 * time.Minute,
	}
	return srv.ListenAndServe()
}

type trackingResponseWriter struct {
	http.ResponseWriter
	wroteHeader bool
}

func (w *trackingResponseWriter) WriteHeader(statusCode int) {
	w.wroteHeader = true
	w.ResponseWriter.WriteHeader(statusCode)
}

func (w *trackingResponseWriter) Write(p []byte) (int, error) {
	w.wroteHeader = true
	return w.ResponseWriter.Write(p)
}

func (w *trackingResponseWriter) Flush() {
	w.wroteHeader = true
	if f, ok := w.ResponseWriter.(http.Flusher); ok {
		f.Flush()
	}
}

func (w *trackingResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
	h, ok := w.ResponseWriter.(http.Hijacker)
	if !ok {
		return nil, nil, fmt.Errorf("hijacking not supported")
	}
	return h.Hijack()
}

func (w *trackingResponseWriter) Push(target string, opts *http.PushOptions) error {
	p, ok := w.ResponseWriter.(http.Pusher)
	if !ok {
		return http.ErrNotSupported
	}
	return p.Push(target, opts)
}

func (w *trackingResponseWriter) ReadFrom(r io.Reader) (int64, error) {
	rf, ok := w.ResponseWriter.(io.ReaderFrom)
	if !ok {
		return io.Copy(w.ResponseWriter, r)
	}
	w.wroteHeader = true
	return rf.ReadFrom(r)
}

func recoverMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		tw := &trackingResponseWriter{ResponseWriter: w}
		defer func() {
			if rec := recover(); rec != nil {
				slog.Error("http handler panic",
					"method", r.Method,
					"path", r.URL.Path,
					"panic", fmt.Sprint(rec),
					"stack", string(debug.Stack()),
				)
				if !tw.wroteHeader {
					http.Error(tw, "internal server error", http.StatusInternalServerError)
				}
			}
		}()
		next.ServeHTTP(tw, r)
	})
}

// ── Infrastructure handlers ──────────────────────────────────────────────────

func (h *handler) handleHealthz(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Cache-Control", "no-store")
	w.WriteHeader(http.StatusOK)
	_, _ = w.Write([]byte("ok"))
}

// ── Compatibility endpoints ──────────────────────────────────────────────────

func (h *handler) handleAuditJSON(w http.ResponseWriter, r *http.Request) {
	data, err := loadSnapshot(h.opts.AuditPath)
	if err != nil {
		if errors.Is(err, os.ErrNotExist) {
			http.Error(w, "audit snapshot not found", http.StatusNotFound)
			return
		}
		http.Error(w, fmt.Sprintf("read audit snapshot: %v", err), http.StatusInternalServerError)
		return
	}
	// Re-apply SAT overlay on every request so that SAT results run after the
	// last audit always appear in the downloaded JSON without needing a re-audit.
	if overlaid, err := app.ApplySATOverlay(data); err == nil {
		data = overlaid
	}
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	_, _ = w.Write(data)
}

func (h *handler) handleRuntimeHealthJSON(w http.ResponseWriter, r *http.Request) {
	data, err := loadSnapshot(filepath.Join(h.opts.ExportDir, "runtime-health.json"))
	if err != nil {
		if errors.Is(err, os.ErrNotExist) {
			http.Error(w, "runtime health not found", http.StatusNotFound)
			return
		}
		http.Error(w, fmt.Sprintf("read runtime health: %v", err), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	_, _ = w.Write(data)
}

func (h *handler) handleSupportBundleDownload(w http.ResponseWriter, r *http.Request) {
	archive, err := app.BuildSupportBundle(h.opts.ExportDir)
	if err != nil {
		http.Error(w, fmt.Sprintf("build support bundle: %v", err), http.StatusInternalServerError)
		return
	}
	defer os.Remove(archive)
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Content-Type", "application/gzip")
	w.Header().Set("Content-Disposition", fmt.Sprintf("attachment; filename=%q", filepath.Base(archive)))
	http.ServeFile(w, r, archive)
}

func (h *handler) handleExportFile(w http.ResponseWriter, r *http.Request) {
	rel := strings.TrimSpace(r.URL.Query().Get("path"))
	if rel == "" {
		http.Error(w, "path is required", http.StatusBadRequest)
		return
	}
	clean := filepath.Clean(rel)
	if clean == "." || strings.HasPrefix(clean, "..") {
		http.Error(w, "invalid path", http.StatusBadRequest)
		return
	}
	// Set Content-Type explicitly to avoid mime.TypeByExtension which panics on
	// LiveCD environments where /usr/share/mime/globs2 has an I/O read error.
	w.Header().Set("Content-Type", mimeByExt(filepath.Ext(clean)))
	http.ServeFile(w, r, filepath.Join(h.opts.ExportDir, clean))
}

// mimeByExt returns a Content-Type for known extensions, falling back to
// application/octet-stream. Used to avoid calling mime.TypeByExtension.
func mimeByExt(ext string) string {
	switch strings.ToLower(ext) {
	case ".json":
		return "application/json"
	case ".gz":
		return "application/gzip"
	case ".tar":
		return "application/x-tar"
	case ".log", ".txt":
		return "text/plain; charset=utf-8"
	case ".html":
		return "text/html; charset=utf-8"
	case ".svg":
		return "image/svg+xml"
	default:
		return "application/octet-stream"
	}
}

func (h *handler) handleExportIndex(w http.ResponseWriter, r *http.Request) {
	body, err := renderExportIndex(h.opts.ExportDir)
	if err != nil {
		http.Error(w, fmt.Sprintf("render export index: %v", err), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	_, _ = w.Write([]byte(body))
}

func (h *handler) handleViewer(w http.ResponseWriter, r *http.Request) {
	snapshot, _ := loadSnapshot(h.opts.AuditPath)
	snapshot = enrichSnapshotForViewer(snapshot)
	body, err := viewer.RenderHTML(snapshot, h.opts.Title)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	_, _ = w.Write(body)
}

func (h *handler) handleAPIMetricsExportCSV(w http.ResponseWriter, r *http.Request) {
	if h.metricsDB == nil {
		http.Error(w, "metrics database not available", http.StatusServiceUnavailable)
		return
	}
	w.Header().Set("Content-Type", "text/csv; charset=utf-8")
	w.Header().Set("Content-Disposition", `attachment; filename="bee-metrics.csv"`)
	w.Header().Set("Cache-Control", "no-store")
	_ = h.metricsDB.ExportCSV(w)
}

// ── Page handler ─────────────────────────────────────────────────────────────

func (h *handler) handleReady(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Cache-Control", "no-store")
	if strings.TrimSpace(h.opts.AuditPath) == "" {
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte("ready"))
		return
	}
	if _, err := os.Stat(h.opts.AuditPath); err != nil {
		w.WriteHeader(http.StatusServiceUnavailable)
		_, _ = w.Write([]byte("starting"))
		return
	}
	w.WriteHeader(http.StatusOK)
	_, _ = w.Write([]byte("ready"))
}

const loadingPageHTML = `<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>EASY-BEE — Starting</title>
<style>
*{margin:0;padding:0;box-sizing:border-box}
html,body{height:100%;background:#0f1117;display:flex;align-items:center;justify-content:center;font-family:'Courier New',monospace;color:#e2e8f0}
.wrap{text-align:center;width:420px}
.brand{font-size:22px;letter-spacing:.18em;color:#f6c90e;margin-bottom:6px;text-align:left}
.subtitle{font-size:12px;color:#a0aec0;text-align:left;margin-bottom:24px}
.spinner{width:36px;height:36px;border:3px solid #2d3748;border-top-color:#f6c90e;border-radius:50%;animation:spin .8s linear infinite;margin:0 auto 14px}
.spinner.hidden{display:none}
@keyframes spin{to{transform:rotate(360deg)}}
.status{font-size:13px;color:#a0aec0;margin-bottom:20px;min-height:18px}
table{width:100%;border-collapse:collapse;font-size:12px;margin-bottom:20px;display:none}
td{padding:3px 6px;text-align:left}
td:first-child{color:#718096;width:55%}
.ok{color:#68d391}
.run{color:#f6c90e}
.fail{color:#fc8181}
.dim{color:#4a5568}
.btn{background:#1a202c;color:#a0aec0;border:1px solid #2d3748;padding:7px 18px;font-size:12px;cursor:pointer;font-family:inherit;display:none}
.btn:hover{border-color:#718096;color:#e2e8f0}
</style>
</head>
<body>
<div class="wrap">
  <div class="brand">EASY BEE</div>
  <div class="subtitle">Hardware Audit LiveCD</div>
  <div class="spinner" id="spin"></div>
  <div class="status" id="st">Connecting to bee-web...</div>
  <table id="tbl"></table>
  <button class="btn" id="btn" onclick="go()">Open app now</button>
</div>
<script>
(function(){
var gone = false;
var pollStarted = false;
var fallbackOpenTimer = null;
var AUTO_OPEN_DELAY_MS = 15000;
function go(){ if(!gone){gone=true;window.location.replace('/');} }

function scheduleFallbackOpen(){
  if(fallbackOpenTimer!==null) return;
  fallbackOpenTimer=setTimeout(function(){
    document.getElementById('spin').className='spinner hidden';
    document.getElementById('st').textContent='Startup checks are taking too long — opening app...';
    go();
  },AUTO_OPEN_DELAY_MS);
}

function icon(s){
  if(s==='active')   return '<span class="ok">&#9679; active</span>';
  if(s==='failed')   return '<span class="fail">&#10005; failed</span>';
  if(s==='activating'||s==='reloading') return '<span class="run">&#9675; starting</span>';
  if(s==='inactive') return '<span class="dim">&#9675; inactive</span>';
  return '<span class="dim">'+s+'</span>';
}

function allSettled(svcs){
  for(var i=0;i<svcs.length;i++){
    var s=svcs[i].state;
    if(s!=='active'&&s!=='failed'&&s!=='inactive') return false;
  }
  return true;
}

var pollTimer=null;

function pollServices(){
  fetch('/api/services',{cache:'no-store'})
    .then(function(r){return r.json();})
    .then(function(svcs){
      if(!svcs||!svcs.length) return;
      var tbl=document.getElementById('tbl');
      tbl.style.display='';
      var html='';
      for(var i=0;i<svcs.length;i++)
        html+='<tr><td>'+svcs[i].name+'</td><td>'+icon(svcs[i].state)+'</td></tr>';
      tbl.innerHTML=html;
      if(allSettled(svcs)){
        clearInterval(pollTimer);
        if(fallbackOpenTimer!==null) clearTimeout(fallbackOpenTimer);
        document.getElementById('spin').className='spinner hidden';
        document.getElementById('st').textContent='Ready \u2014 opening...';
        setTimeout(go,800);
      }
    })
    .catch(function(){});
}

function probe(){
  fetch('/healthz',{cache:'no-store'})
    .then(function(r){
      if(r.ok){
        document.getElementById('st').textContent='bee-web running \u2014 checking services...';
        document.getElementById('btn').style.display='';
        scheduleFallbackOpen();
        if(!pollStarted){
          pollStarted=true;
          pollServices();
          pollTimer=setInterval(pollServices,1500);
        }
      } else {
        document.getElementById('st').textContent='bee-web starting (status '+r.status+')...';
        setTimeout(probe,500);
      }
    })
    .catch(function(){
      document.getElementById('st').textContent='Waiting for bee-web to start...';
      setTimeout(probe,500);
    });
}
probe();
})();
</script>
</body>
</html>`

func (h *handler) handlePage(w http.ResponseWriter, r *http.Request) {
	page := strings.TrimPrefix(r.URL.Path, "/")
	if page == "" {
		page = "dashboard"
	}
	// Redirect legacy routes to new named pages
	switch page {
	case "validate", "tests":
		http.Redirect(w, r, "/load", http.StatusMovedPermanently)
		return
	case "burn-in":
		http.Redirect(w, r, "/burn", http.StatusMovedPermanently)
		return
	case "speed", "endurance":
		http.Redirect(w, r, "/benchmark", http.StatusMovedPermanently)
		return
	}
	body := renderPage(page, h.opts)
	w.Header().Set("Cache-Control", "no-store")
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	_, _ = w.Write([]byte(body))
}

// ── Helpers ──────────────────────────────────────────────────────────────────

func loadSnapshot(path string) ([]byte, error) {
	if strings.TrimSpace(path) == "" {
		return nil, os.ErrNotExist
	}
	return os.ReadFile(path)
}

// writeJSON sends v as JSON with status 200.
func writeJSON(w http.ResponseWriter, v any) {
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	w.Header().Set("Cache-Control", "no-store")
	_ = json.NewEncoder(w).Encode(v)
}

// writeError sends a JSON error response.
func writeError(w http.ResponseWriter, status int, msg string) {
	w.Header().Set("Content-Type", "application/json; charset=utf-8")
	w.Header().Set("Cache-Control", "no-store")
	w.WriteHeader(status)
	_ = json.NewEncoder(w).Encode(map[string]string{"error": msg})
}

func writeAPIListResponse[T any](w http.ResponseWriter, configured bool, load func() ([]T, error)) {
	if !configured {
		writeError(w, http.StatusServiceUnavailable, "app not configured")
		return
	}
	items, err := load()
	if err != nil {
		writeError(w, http.StatusInternalServerError, err.Error())
		return
	}
	if items == nil {
		items = []T{}
	}
	writeJSON(w, items)
}