// Command geniusrund is geniusrun's backend server: syncs runs from Garmin,
// classifies them into workout kinds, and serves the REST API the frontend
// talks to.
package main

import (
	"context"
	"log"
	"log/slog"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"geniusrun/backend/internal/api"
	"geniusrun/backend/internal/auth"
	"geniusrun/backend/internal/config"
	"geniusrun/backend/internal/garmin"
	"geniusrun/backend/internal/log"
	"geniusrun/backend/internal/store"
)

func main() {
	envCfg, err := config.LoadEnv()
	if err != nil {
		log.Fatalf("config: %v", err)
	}
	slog.SetDefault(applog.NewLogger(envCfg.LogLevel, os.Stdout))

	db, err := store.Open(envCfg.DBPath)
	if err != nil {
		log.Fatalf("open database: %v", err)
	}
	defer db.Close()

	overrides, err := db.ConfigValues(context.Background())
	if err != nil {
		log.Fatalf("app config: %v", err)
	}
	appCfg, err := config.LoadApp(overrides)
	if err != nil {
		log.Fatalf("app config: %v", err)
	}

	authVerifier, err := auth.NewOIDCVerifier(context.Background(), auth.OIDCConfig{
		IssuerURL:    envCfg.OIDCIssuerURL,
		ClientID:     envCfg.OIDCClientID,
		ClientSecret: envCfg.OIDCClientSecret,
		RedirectURL:  envCfg.OIDCRedirectURL,
		RequiredRole: envCfg.OIDCRequiredRole,
	})
	if err != nil {
		log.Fatalf("oidc: %v", err)
	}

	server := api.NewServer(
		db,
		garmin.NewClient,
		garmin.ClientConfig{
			PythonPath:     envCfg.PythonPath,
			TokenStorePath: envCfg.TokenStoreRoot,
		},
		garmin.SyncConfig{},
		authVerifier,
		api.SessionConfig{
			Secret:      envCfg.SessionSecret,
			Duration:    appCfg.SessionDuration,
			Secure:      envCfg.SessionSecure,
			BackendURL:  envCfg.BackendURL,
			FrontendURL: envCfg.FrontendURL,
		})

	for _, e := range envCfg.DisplayEnv() {
		server.EnvVars = append(server.EnvVars, api.EnvVar{Name: e.Name, Value: e.Value})
	}

	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
	defer stop()

	httpServer := &http.Server{Addr: envCfg.BackendAddr, Handler: server.Router()}
	go func() {
		log.Printf("geniusrund listening on %s", envCfg.BackendAddr)
		if err := httpServer.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			log.Fatalf("http server: %v", err)
		}
	}()

	<-ctx.Done()
	log.Println("shutting down...")
	shutdownCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	if err := httpServer.Shutdown(shutdownCtx); err != nil {
		log.Printf("http server shutdown: %v", err)
	}
}