// This file is part of the happyDeliver (R) project.
// Copyright (c) 2025 happyDomain
// Authors: Pierre-Olivier Mercier, et al.
//
// This program is offered under a commercial and under the AGPL license.
// For commercial licensing, contact us at <contact@happydomain.org>.
//
// For AGPL licensing:
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

package app

import (
	"context"
	"log"
	"os"
	"time"

	ratelimit "github.com/JGLTechnologies/gin-rate-limit"
	"github.com/gin-gonic/gin"

	"git.happydns.org/happyDeliver/internal/api"
	"git.happydns.org/happyDeliver/internal/config"
	"git.happydns.org/happyDeliver/internal/lmtp"
	"git.happydns.org/happyDeliver/internal/storage"
	"git.happydns.org/happyDeliver/pkg/analyzer"
	"git.happydns.org/happyDeliver/web"
)

// RunServer starts the API server and LMTP server
func RunServer(cfg *config.Config) error {
	if err := cfg.Validate(); err != nil {
		return err
	}

	// Initialize storage
	store, err := storage.NewStorage(cfg.Database.Type, cfg.Database.DSN)
	if err != nil {
		return err
	}
	defer store.Close()

	log.Printf("Connected to %s database", cfg.Database.Type)

	// Start cleanup service for old reports
	ctx := context.Background()
	cleanupSvc := NewCleanupService(store, cfg.ReportRetention)
	cleanupSvc.Start(ctx)
	defer cleanupSvc.Stop()

	// Start LMTP server in background
	go func() {
		if err := lmtp.StartServer(cfg.Email.LMTPAddr, store, cfg); err != nil {
			log.Fatalf("Failed to start LMTP server: %v", err)
		}
	}()

	// Create analyzer adapter for API
	analyzerAdapter := analyzer.NewAPIAdapter(cfg)

	// Create API handler
	handler := api.NewAPIHandler(store, cfg, analyzerAdapter)

	// Set up Gin router
	if os.Getenv("GIN_MODE") == "" {
		gin.SetMode(gin.ReleaseMode)
	}
	router := gin.Default()

	apiGroup := router.Group("/api")

	if cfg.RateLimit > 0 {
		// Set up rate limiting (2x to handle burst)
		rateLimitStore := ratelimit.InMemoryStore(&ratelimit.InMemoryOptions{
			Rate:  2 * time.Second,
			Limit: 2 * cfg.RateLimit,
		})
		rateLimiter := ratelimit.RateLimiter(rateLimitStore, &ratelimit.Options{
			ErrorHandler: func(c *gin.Context, info ratelimit.Info) {
				c.JSON(429, gin.H{
					"error":   "rate_limit_exceeded",
					"message": "Too many requests. Try again in " + time.Until(info.ResetTime).String(),
				})
			},
			KeyFunc: func(c *gin.Context) string {
				return c.ClientIP()
			},
		})

		apiGroup.Use(rateLimiter)
	}

	// Register API routes
	api.RegisterHandlers(apiGroup, handler)
	web.DeclareRoutes(cfg, router)

	// Start API server
	log.Printf("Starting API server on %s", cfg.Bind)
	log.Printf("Test email domain: %s", cfg.Email.Domain)

	if err := router.Run(cfg.Bind); err != nil {
		return err
	}

	return nil
}