minstrel/internal/server/server.go

package server

import (
	"context"
	"encoding/json"
	"log/slog"
	"net/http"
	"strings"

	"github.com/go-chi/chi/v5"
	"github.com/go-chi/chi/v5/middleware"
	"github.com/jackc/pgx/v5/pgxpool"

	"time"

	"git.fabledsword.com/bvandeusen/minstrel/internal/api"
	"git.fabledsword.com/bvandeusen/minstrel/internal/auth"
	"git.fabledsword.com/bvandeusen/minstrel/internal/backup"
	"git.fabledsword.com/bvandeusen/minstrel/internal/buildinfo"
	"git.fabledsword.com/bvandeusen/minstrel/internal/config"
	"git.fabledsword.com/bvandeusen/minstrel/internal/coverart"
	"git.fabledsword.com/bvandeusen/minstrel/internal/eventbus"
	"git.fabledsword.com/bvandeusen/minstrel/internal/library"
	"git.fabledsword.com/bvandeusen/minstrel/internal/mailer"
	"git.fabledsword.com/bvandeusen/minstrel/internal/netsettings"
	"git.fabledsword.com/bvandeusen/minstrel/internal/playevents"
	"git.fabledsword.com/bvandeusen/minstrel/internal/playlists"
	"git.fabledsword.com/bvandeusen/minstrel/internal/quarantine"
	"git.fabledsword.com/bvandeusen/minstrel/internal/reacquisition"
	"git.fabledsword.com/bvandeusen/minstrel/internal/recsettings"
	"git.fabledsword.com/bvandeusen/minstrel/internal/requests"
	"git.fabledsword.com/bvandeusen/minstrel/internal/subsonic"
	"git.fabledsword.com/bvandeusen/minstrel/internal/tags"
	"git.fabledsword.com/bvandeusen/minstrel/internal/tracks"
	"git.fabledsword.com/bvandeusen/minstrel/web"
)

// ScanTrigger is the subset of the scanner the HTTP handler needs. Kept as an
// interface so tests can stub it without touching the DB. The progressCb
// parameter (added in m7-scan-progress) lets the orchestrator drive partial-
// tally writes; the HTTP handler passes nil for fire-and-forget triggers.
type ScanTrigger interface {
	Scan(ctx context.Context, progressCb func(library.Stats)) (library.Stats, error)
}

type Server struct {
	Logger            *slog.Logger
	Pool              *pgxpool.Pool
	Scanner           ScanTrigger
	SubsonicCfg       subsonic.Config
	EventsCfg         config.EventsConfig
	RecommendationCfg config.RecommendationConfig
	// DataDir is the on-disk root for cached artifacts (currently
	// playlist cover collages under <DataDir>/playlist_covers/). Empty
	// strings are tolerated by tests that don't exercise persisted-cover
	// codepaths; production callers should pass a writable directory.
	DataDir        string
	BrandingCfg    config.BrandingConfig
	CoverEnricher  *coverart.Enricher
	CoverSettings  *coverart.SettingsService
	TagSettings    *tags.SettingsService
	LibraryScanner *library.Scanner
	ScanCfg        library.RunScanConfig
	// Bus is the live-event bus shared with background workers (the
	// request reconciler, scan workers) constructed in cmd/minstrel/main.go.
	// When nil, Router() constructs a local fallback (test contexts).
	Bus *eventbus.Bus
	// PlaylistScheduler fires per-user daily system-playlist builds at
	// 03:00 in each user's stored timezone. Constructed
	// in cmd/minstrel/main.go and threaded into the API handlers so
	// PUT /api/me/timezone and POST /api/auth/register can call
	// Refresh synchronously.
	PlaylistScheduler *playlists.Scheduler
	// RecSettings is the DB-backed recommendation tuning:
	// scoring-weight profiles + taste-build knobs. Constructed in
	// cmd/minstrel/main.go (it pushes daily-mix weights into package
	// playlists at boot); the API layer reads radio weights per request
	// and serves the admin tuning endpoints from it. Router() constructs
	// a fallback when nil (tests).
	RecSettings *recsettings.Service
	// FingerprintSettings is the DB-backed fingerprinting policy.
	// Constructed in cmd/minstrel/main.go and shared with the scanner and the
	// fingerprint workers, so a save from the admin card reaches them without a
	// restart. Router() constructs a fallback when nil (tests).
	FingerprintSettings *library.FingerprintSettingsService
	// LoudnessSettings is the DB-backed loudness analysis policy,
	// shared with the loudness backfill. Nil makes the router load its own.
	LoudnessSettings *library.LoudnessSettingsService
	// AcoustIDLookup is the AcoustID lookup worker, whose settings,
	// status and "look up now" the admin card drives. Nil in test contexts;
	// one is built (and never run) so the admin routes still answer.
	AcoustIDLookup *library.AcoustIDLookupWorker
	// ReacqSettings is the DB-backed missing-file re-acquisition policy — the
	// same instance the sweeper in cmd/minstrel/main.go reads, so a save from
	// the admin card reaches it without a restart. Router() constructs a
	// fallback when nil (tests).
	ReacqSettings *reacquisition.SettingsService
	// Backups is the server's own backup, the instance whose loop runs the
	// nightly schedule. Nil builds one that runs only when an admin asks.
	Backups *backup.Service
	// StreamSecret is the HMAC key used by /api/cast/stream-token to
	// mint signed UPnP / Sonos stream URLs and by /api/tracks/{id}/stream
	// to verify them. Sourced from config.Config.StreamSecret. Tests that
	// leave it nil leave the cookie path intact and reject all signed
	// tokens (HMAC of empty key matches nothing a client could mint).
	StreamSecret []byte
	// Restart asks the process to stop and start again in place. A web
	// restore calls it so the restored settings are read at boot.
	Restart func()
}

func New(logger *slog.Logger, pool *pgxpool.Pool, scanner ScanTrigger, subCfg subsonic.Config, eventsCfg config.EventsConfig, recCfg config.RecommendationConfig, dataDir string, brandingCfg config.BrandingConfig, coverEnricher *coverart.Enricher, coverSettings *coverart.SettingsService, libraryScanner *library.Scanner, scanCfg library.RunScanConfig) *Server {
	return &Server{Logger: logger, Pool: pool, Scanner: scanner, SubsonicCfg: subCfg, EventsCfg: eventsCfg, RecommendationCfg: recCfg, DataDir: dataDir, BrandingCfg: brandingCfg, CoverEnricher: coverEnricher, CoverSettings: coverSettings, LibraryScanner: libraryScanner, ScanCfg: scanCfg}
}

func (s *Server) Router() http.Handler {
	r := chi.NewRouter()

	// Built before the router because the access log needs it, and the access
	// log covers /healthz and the SPA — which exist whether or not there's a
	// pool. netsettings.New handles a nil pool by returning a default-valued
	// service, so this needs no branch and no later reassignment; hoisting it
	// here keeps the accessor a plain method value instead of a closure over
	// a variable mutated after the middleware is already registered.
	netSettings, nsErr := netsettings.New(context.Background(), s.Pool, s.Logger)
	if nsErr != nil {
		s.Logger.Error("server: netsettings boot failed, using default hops", "err", nsErr)
	}

	r.Use(middleware.RequestID)
	r.Use(requestLog(s.Logger, netSettings.Hops))
	r.Use(middleware.Recoverer)
	r.Use(securityHeaders(netSettings.Hops))
	r.Use(limitRequestBody)
	r.Use(requireJSONForCookieWrites)

	r.Get("/healthz", s.handleHealthz)

	if s.Pool != nil {
		writer := playevents.NewWriter(
			s.Pool, s.Logger,
			time.Duration(s.EventsCfg.SessionTimeoutMinutes)*time.Minute,
			s.EventsCfg.SkipMaxCompletionRatio,
			s.EventsCfg.SkipMaxDurationPlayedMs,
		)
		requestSvc := requests.NewService(s.Pool)
		reacqSettings := s.ReacqSettings
		if reacqSettings == nil {
			// Test contexts construct Server without main.go's boot wiring.
			// Always usable even when the load fails — it falls back to the
			// shipped defaults rather than leaving the admin card unable to
			// render (same posture as netsettings above).
			var raErr error
			reacqSettings, raErr = reacquisition.NewSettingsService(
				context.Background(), s.Pool, s.Logger)
			if raErr != nil {
				s.Logger.Warn("reacquisition settings unavailable; serving defaults", "err", raErr)
			}
		}
		quarantineSvc := quarantine.NewService(s.Pool, s.DataDir)
		tracksSvc := tracks.NewService(s.Pool, s.Logger, s.DataDir)
		playlistsSvc := playlists.NewService(s.Pool, s.Logger, s.DataDir)
		smtpSender := mailer.NewSMTPSender(s.Pool, s.Logger.With("component", "mailer"))
		// Live-event bus for SSE subscribers, one per process: producers in
		// playevents / requests / scanner publish into the same instance.
		// Background workers are built in cmd/minstrel/main.go before Router()
		// runs and share s.Bus. With no bus set (tests), a fresh local one is
		// used.
		bus := s.Bus
		if bus == nil {
			bus = eventbus.New()
		}
		recSettings := s.RecSettings
		if recSettings == nil {
			// Test contexts construct Server directly without main.go's
			// boot wiring; reconcile here so radio + the admin tuning
			// endpoints work against the same pool.
			var err error
			recSettings, err = recsettings.New(context.Background(), s.Pool, s.Logger)
			if err != nil {
				s.Logger.Error("server: recsettings boot failed", "err", err)
			}
		}
		fpSettings := s.FingerprintSettings
		if fpSettings == nil {
			// Test contexts construct Server without main.go's wiring. Always
			// usable: a failed load serves the defaults.
			var err error
			fpSettings, err = library.NewFingerprintSettingsService(context.Background(), s.Pool)
			if err != nil {
				s.Logger.Warn("fingerprint settings unavailable; serving defaults", "err", err)
			}
		}
		loudSettings := s.LoudnessSettings
		if loudSettings == nil {
			var err error
			loudSettings, err = library.NewLoudnessSettingsService(context.Background(), s.Pool)
			if err != nil {
				s.Logger.Warn("loudness settings unavailable; serving defaults", "err", err)
			}
		}
		acoustIDLookup := s.AcoustIDLookup
		if acoustIDLookup == nil {
			acoustIDSettings, err := library.NewAcoustIDSettingsService(context.Background(), s.Pool)
			if err != nil {
				s.Logger.Warn("acoustid settings unavailable; serving defaults", "err", err)
			}
			acoustIDLookup = library.NewAcoustIDLookupWorker(s.Pool, s.Logger, acoustIDSettings, nil)
		}
		backups := s.Backups
		if backups == nil {
			backups = backup.NewService(s.Pool, s.Logger, buildinfo.Version)
		}
		api.Mount(r, s.Pool, s.Logger, writer, s.RecommendationCfg, recSettings, requestSvc, quarantineSvc, tracksSvc, playlistsSvc, s.CoverEnricher, s.CoverSettings, s.TagSettings, s.LibraryScanner, s.ScanCfg, s.DataDir, smtpSender, bus, s.PlaylistScheduler, s.StreamSecret, netSettings, reacqSettings, fpSettings, loudSettings, acoustIDLookup, backups, s.Restart)
		// /api/admin/scan is the only admin route owned by the server package
		// (it needs the Scanner). Register it as a single inline-middleware
		// route — using r.Route("/api/admin", ...) here would create a second
		// subtree that shadows every admin route registered by api.Mount.
		if s.Scanner != nil {
			r.With(auth.RequireUser(s.Pool, netSettings.Hops), auth.RequireAdmin()).
				Post("/api/admin/scan", s.handleAdminScan)
		}
		subsonic.Mount(r, s.Pool, s.Logger, s.SubsonicCfg, writer, netSettings.Hops)
	}

	spa := web.Handler(s.BrandingCfg)
	r.NotFound(func(w http.ResponseWriter, req *http.Request) {
		p := req.URL.Path
		if strings.HasPrefix(p, "/api/") || strings.HasPrefix(p, "/rest/") {
			w.Header().Set("Content-Type", "application/json")
			w.WriteHeader(http.StatusNotFound)
			_, _ = w.Write([]byte(`{"error":{"code":"not_found","message":"not found"}}`))
			return
		}
		spa.ServeHTTP(w, req)
	})
	return r
}

func (s *Server) handleHealthz(w http.ResponseWriter, _ *http.Request) {
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusOK)
	_ = json.NewEncoder(w).Encode(map[string]string{
		"status":             "ok",
		"version":            buildinfo.Version,
		"channel":            buildinfo.Channel,
		"min_client_version": MinClientVersion,
	})
}

// handleAdminScan runs a scan synchronously and returns the resulting stats.
// Synchronous, so the caller can tell when it's done; the scan's progress is
// also published as scan-run events.
func (s *Server) handleAdminScan(w http.ResponseWriter, r *http.Request) {
	stats, err := s.Scanner.Scan(r.Context(), nil)
	w.Header().Set("Content-Type", "application/json")
	if err != nil {
		s.Logger.Error("admin scan failed", "err", err)
		w.WriteHeader(http.StatusInternalServerError)
		_ = json.NewEncoder(w).Encode(map[string]any{"error": err.Error(), "stats": stats})
		return
	}
	w.WriteHeader(http.StatusOK)
	_ = json.NewEncoder(w).Encode(stats)
}