package bootstrap

import (
	"FileRelay/internal/config"
	"FileRelay/internal/model"
	"FileRelay/internal/storage"
	"context"
	"crypto/rand"
	"fmt"
	"log"
	"math/big"

	"github.com/glebarez/sqlite"
	"golang.org/x/crypto/bcrypt"
	"gorm.io/gorm"
)

var DB *gorm.DB

func InitDB() {
	var err error
	dbPath := config.GlobalConfig.Database.Path
	if dbPath == "" {
		dbPath = "file_relay.db"
	}

	DB, err = gorm.Open(sqlite.Open(dbPath), &gorm.Config{})
	if err != nil {
		log.Fatalf("Failed to connect to database: %v", err)
	}

	// 自动迁移
	err = DB.AutoMigrate(
		&model.FileBatch{},
		&model.FileItem{},
		&model.APIToken{},
		&model.Admin{},
	)
	if err != nil {
		log.Fatalf("Failed to migrate database: %v", err)
	}

	fmt.Println("Database initialized and migrated.")

	// 初始化存储
	if err := ReloadStorage(); err != nil {
		log.Fatalf("Failed to initialize storage: %v", err)
	}

	// 初始化管理员 (如果不存在)
	initAdmin()
}

func ReloadStorage() error {
	storageType := config.GlobalConfig.Storage.Type
	switch storageType {
	case "local":
		storage.GlobalStorage = storage.NewLocalStorage(config.GlobalConfig.Storage.Local.Path)
	case "webdav":
		cfg := config.GlobalConfig.Storage.WebDAV
		storage.GlobalStorage = storage.NewWebDAVStorage(cfg.URL, cfg.Username, cfg.Password, cfg.Root)
	case "s3":
		cfg := config.GlobalConfig.Storage.S3
		s3Storage, err := storage.NewS3Storage(context.Background(), cfg.Endpoint, cfg.Region, cfg.AccessKey, cfg.SecretKey, cfg.Bucket, cfg.UseSSL)
		if err != nil {
			return err
		}
		storage.GlobalStorage = s3Storage
	default:
		return fmt.Errorf("unsupported storage type: %s", storageType)
	}
	fmt.Printf("Storage initialized with type: %s\n", storageType)
	return nil
}

func initAdmin() {
	var count int64
	DB.Model(&model.Admin{}).Count(&count)
	if count == 0 {
		passwordHash := config.GlobalConfig.Security.AdminPasswordHash
		if passwordHash == "" {
			// 生成随机密码
			password := generateRandomPassword(12)
			hash, err := bcrypt.GenerateFromPassword([]byte(password), bcrypt.DefaultCost)
			if err != nil {
				log.Fatalf("Failed to generate password hash: %v", err)
			}
			passwordHash = string(hash)
			fmt.Printf("**************************************************\n")
			fmt.Printf("NO ADMIN PASSWORD CONFIGURED. GENERATED RANDOM PASSWORD:\n")
			fmt.Printf("Password: %s\n", password)
			fmt.Printf("Please save this password or configure admin_password_hash in config.yaml\n")
			fmt.Printf("**************************************************\n")
		}

		admin := &model.Admin{
			PasswordHash: passwordHash,
		}
		DB.Create(admin)
		fmt.Println("Admin account initialized.")
	}
}

func generateRandomPassword(length int) string {
	const charset = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*"
	b := make([]byte, length)
	for i := range b {
		num, err := rand.Int(rand.Reader, big.NewInt(int64(len(charset))))
		if err != nil {
			return "admin123" // 退路
		}
		b[i] = charset[num.Int64()]
	}
	return string(b)
}