package main

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

	"edp.buildth.ing/DevFW-CICD/forgejo-runner-optimiser/internal/receiver"
)

const (
	defaultAddr   = ":8080"
	defaultDBPath = "metrics.db"
)

func main() {
	addr := flag.String("addr", defaultAddr, "HTTP listen address")
	dbPath := flag.String("db", defaultDBPath, "SQLite database path")
	readToken := flag.String("read-token", os.Getenv("RECEIVER_READ_TOKEN"), "Pre-shared token for read endpoints (or set RECEIVER_READ_TOKEN)")
	hmacKey := flag.String("hmac-key", os.Getenv("RECEIVER_HMAC_KEY"), "Secret key for push token generation/validation (or set RECEIVER_HMAC_KEY)")
	tokenTTL := flag.Duration("token-ttl", 2*time.Hour, "Time-to-live for push tokens (default 2h)")
	flag.Parse()

	logger := slog.New(slog.NewJSONHandler(os.Stderr, &slog.HandlerOptions{
		Level: slog.LevelInfo,
	}))

	store, err := receiver.NewStore(*dbPath)
	if err != nil {
		logger.Error("failed to open database", slog.String("error", err.Error()))
		os.Exit(1)
	}
	defer func() { _ = store.Close() }()

	handler := receiver.NewHandler(store, logger, *readToken, *hmacKey, *tokenTTL)
	mux := http.NewServeMux()
	handler.RegisterRoutes(mux)

	server := &http.Server{
		Addr:         *addr,
		Handler:      mux,
		ReadTimeout:  10 * time.Second,
		WriteTimeout: 10 * time.Second,
	}

	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	sigChan := make(chan os.Signal, 1)
	signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)

	go func() {
		sig := <-sigChan
		logger.Info("received signal, shutting down", slog.String("signal", sig.String()))
		cancel()

		shutdownCtx, shutdownCancel := context.WithTimeout(context.Background(), 5*time.Second)
		defer shutdownCancel()
		_ = server.Shutdown(shutdownCtx)
	}()

	logger.Info("starting metrics receiver",
		slog.String("addr", *addr),
		slog.String("db", *dbPath),
	)

	if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
		fmt.Fprintf(os.Stderr, "error: %v\n", err)
		os.Exit(1)
	}

	<-ctx.Done()
	logger.Info("receiver stopped gracefully")
}