package main

import (
	"context"
	"log"
	"time"

	"github.com/gofiber/fiber/v3"
	"github.com/gofiber/fiber/v3/middleware/adaptor"

	applb "knowfoolery/backend/services/leaderboard-service/internal/application/leaderboard"
	lbconfig "knowfoolery/backend/services/leaderboard-service/internal/infra/config"
	lbent "knowfoolery/backend/services/leaderboard-service/internal/infra/persistence/ent"
	lbstate "knowfoolery/backend/services/leaderboard-service/internal/infra/state"
	httpapi "knowfoolery/backend/services/leaderboard-service/internal/interfaces/http"
	"knowfoolery/backend/shared/infra/auth/zitadel"
	sharedredis "knowfoolery/backend/shared/infra/database/redis"
	"knowfoolery/backend/shared/infra/observability/logging"
	sharedmetrics "knowfoolery/backend/shared/infra/observability/metrics"
	"knowfoolery/backend/shared/infra/observability/tracing"
	"knowfoolery/backend/shared/infra/utils/serviceboot"
	"knowfoolery/backend/shared/infra/utils/validation"
)

func main() {
	serviceCfg := lbconfig.FromEnv()
	logger := logging.NewLogger(serviceCfg.Logging)
	metrics := sharedmetrics.NewMetrics(serviceCfg.Metrics)

	tracer, err := tracing.NewTracer(serviceCfg.Tracing)
	if err != nil {
		logger.Fatal("failed to initialize tracer")
	}
	defer func() { _ = tracer.Shutdown(context.Background()) }()

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	persistence, err := lbent.NewClient(ctx, serviceCfg.Postgres)
	if err != nil {
		logger.WithError(err).Fatal("failed to initialize postgres client")
	}
	defer persistence.Close()

	repo := lbent.NewLeaderboardRepository(persistence)
	if err := repo.EnsureSchema(ctx); err != nil {
		logger.WithError(err).Fatal("failed to ensure schema")
	}

	var redisClient *sharedredis.Client
	if c, redisErr := sharedredis.NewClient(serviceCfg.Redis); redisErr == nil {
		redisClient = c
		defer func() { _ = redisClient.Close() }()
	} else {
		logger.WithError(redisErr).Warn("redis unavailable; running without cache")
	}

	state := lbstate.NewStore(redisClient)
	service := applb.NewService(repo, state, applb.Config{
		TopLimit:             serviceCfg.TopLimit,
		PlayerHistoryDefault: serviceCfg.PlayerHistoryDefault,
		PlayerHistoryMax:     serviceCfg.PlayerHistoryMax,
		CacheTTL:             serviceCfg.CacheTTL,
		UpdateRequireAuth:    serviceCfg.UpdateRequireAuth,
	})
	handler := httpapi.NewHandler(
		service,
		validation.NewValidator(),
		logger,
		metrics,
		serviceCfg.UpdateRequireAuth,
		serviceCfg.PlayerHistoryDefault,
		serviceCfg.PlayerHistoryMax,
	)

	bootCfg := serviceboot.Config{
		AppName:     serviceCfg.AppName,
		ServiceSlug: "leaderboard",
		PortEnv:     "LEADERBOARD_PORT",
		DefaultPort: serviceCfg.Port,
	}
	app := serviceboot.NewFiberApp(bootCfg)
	serviceboot.RegisterHealth(app, bootCfg.ServiceSlug)
	serviceboot.RegisterReadiness(
		app,
		2*time.Second,
		serviceboot.ReadyCheck{
			Name:     "postgres",
			Required: true,
			Probe:    persistence.Pool.Ping,
		},
		serviceboot.ReadyCheck{
			Name:     "redis",
			Required: false,
			Probe: func(ctx context.Context) error {
				if redisClient == nil {
					return nil
				}
				return redisClient.HealthCheck(ctx)
			},
		},
	)
	app.Get("/metrics", adaptor.HTTPHandler(sharedmetrics.Handler()))

	authMiddleware := buildAuthMiddleware(serviceCfg)
	httpapi.RegisterRoutes(app, handler, authMiddleware)

	addr := serviceboot.ListenAddress(bootCfg.PortEnv, bootCfg.DefaultPort)
	log.Fatal(serviceboot.Run(app, addr))
}

func buildAuthMiddleware(cfg lbconfig.Config) fiber.Handler {
	return zitadel.BuildJWTMiddleware(zitadel.MiddlewareFactoryConfig{
		BaseURL:      cfg.ZitadelBaseURL,
		ClientID:     cfg.ZitadelClientID,
		ClientSecret: cfg.ZitadelSecret,
		Issuer:       cfg.ZitadelIssuer,
		Audience:     cfg.ZitadelAudience,
		RequiredClaims: []string{
			"sub",
		},
		Timeout: 10 * time.Second,
	})
}