// Command server starts the Control Center Go backend API server.
package main

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

	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/config"
	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/db"
	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/handler"
	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/router"
	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/store"
)

func main() {
	// ── Configuration ──────────────────────────────────────────────────────
	cfg := config.Load()

	// ── Logging ────────────────────────────────────────────────────────────
	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
		Level: parseLogLevel(cfg.LogLevel),
	}))
	slog.SetDefault(logger)

	// ── Database (optional until CUB-120 schema is ready) ──────────────────
	var pool *db.Pool
	if cfg.DatabaseURL != "" {
		var err error
		pool, err = db.New(cfg.DatabaseURL)
		if err != nil {
			slog.Warn("database connection failed; running without DB", "error", err)
		}
	}

	// ── Stores (in-memory for now; PostgreSQL after CUB-120) ────────────────
	agentStore := store.NewAgentStore()
	sessionStore := store.NewSessionStore()
	taskStore := store.NewTaskStore()
	projectStore := store.NewProjectStore()

	// ── HTTP handler ───────────────────────────────────────────────────────
	h := handler.NewHandler(agentStore, sessionStore, taskStore, projectStore)

	// ── Router ─────────────────────────────────────────────────────────────
	r := router.New(&router.Dependencies{
		Handler:    h,
		DB:         pool,
		CORSOrigin: cfg.CORSOrigin,
	})

	// ── Server ─────────────────────────────────────────────────────────────
	srv := &http.Server{
		Addr:         fmt.Sprintf(":%d", cfg.Port),
		Handler:      r,
		ReadTimeout:  10 * time.Second,
		WriteTimeout: 15 * time.Second,
		IdleTimeout:  60 * time.Second,
	}

	// Graceful shutdown
	quit := make(chan os.Signal, 1)
	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)

	go func() {
		slog.Info("server starting", "port", cfg.Port, "env", cfg.Environment)
		if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
			slog.Error("server failed", "error", err)
			os.Exit(1)
		}
	}()

	<-quit
	slog.Info("shutting down server...")

	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
	defer cancel()

	if err := srv.Shutdown(ctx); err != nil {
		slog.Error("server forced to shutdown", "error", err)
		os.Exit(1)
	}

	if pool != nil {
		pool.Close()
	}

	slog.Info("server exited cleanly")
}

func parseLogLevel(level string) slog.Level {
	switch level {
	case "debug":
		return slog.LevelDebug
	case "warn":
		return slog.LevelWarn
	case "error":
		return slog.LevelError
	default:
		return slog.LevelInfo
	}
}