package httpapp

import (
	"fmt"
	"html/template"
	"net/http"
	"os"
	"path/filepath"
	"time"

	"gitea.avt.data-center.id/othman.suseno/atlas/internal/audit"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/auth"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/backup"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/db"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/job"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/maintenance"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/metrics"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/services"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/snapshot"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/storage"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/tls"
	"gitea.avt.data-center.id/othman.suseno/atlas/internal/zfs"
)

type Config struct {
	Addr         string
	TemplatesDir string
	StaticDir    string
	DatabasePath string // Path to SQLite database (empty = in-memory mode)
}

type App struct {
	cfg                Config
	tmpl               *template.Template
	mux                *http.ServeMux
	zfs                *zfs.Service
	snapshotPolicy     *snapshot.PolicyStore
	jobManager         *job.Manager
	scheduler          *snapshot.Scheduler
	authService        *auth.Service
	userStore          *auth.UserStore
	auditStore         *audit.Store
	smbStore           *storage.SMBStore
	nfsStore           *storage.NFSStore
	iscsiStore         *storage.ISCSIStore
	database           *db.DB // Optional database connection
	smbService         *services.SMBService
	nfsService         *services.NFSService
	iscsiService       *services.ISCSIService
	metricsCollector   *metrics.Collector
	startTime          time.Time
	backupService      *backup.Service
	maintenanceService *maintenance.Service
	tlsConfig          *tls.Config
}

func New(cfg Config) (*App, error) {
	if cfg.TemplatesDir == "" {
		cfg.TemplatesDir = "web/templates"
	}
	if cfg.StaticDir == "" {
		cfg.StaticDir = "web/static"
	}

	tmpl, err := parseTemplates(cfg.TemplatesDir)
	if err != nil {
		return nil, err
	}

	zfsService := zfs.New()
	policyStore := snapshot.NewPolicyStore()
	jobMgr := job.NewManager()
	scheduler := snapshot.NewScheduler(policyStore, zfsService, jobMgr)

	// Initialize database (optional)
	var database *db.DB
	if cfg.DatabasePath != "" {
		dbConn, err := db.New(cfg.DatabasePath)
		if err != nil {
			return nil, fmt.Errorf("init database: %w", err)
		}
		database = dbConn
	}

	// Initialize auth
	jwtSecret := os.Getenv("ATLAS_JWT_SECRET")
	authService := auth.New(jwtSecret)
	userStore := auth.NewUserStore(authService)

	// Initialize audit logging (keep last 10000 logs)
	auditStore := audit.NewStore(10000)

	// Initialize storage services
	smbStore := storage.NewSMBStore()
	nfsStore := storage.NewNFSStore()
	iscsiStore := storage.NewISCSIStore()

	// Initialize service daemon integrations
	smbService := services.NewSMBService()
	nfsService := services.NewNFSService()
	iscsiService := services.NewISCSIService()

	// Initialize metrics collector
	metricsCollector := metrics.NewCollector()
	startTime := time.Now()

	// Initialize backup service
	backupDir := os.Getenv("ATLAS_BACKUP_DIR")
	if backupDir == "" {
		backupDir = "data/backups"
	}
	backupService, err := backup.New(backupDir)
	if err != nil {
		return nil, fmt.Errorf("init backup service: %w", err)
	}

	// Initialize maintenance service
	maintenanceService := maintenance.NewService()

	// Initialize TLS configuration
	tlsConfig := tls.LoadConfig()
	if err := tlsConfig.Validate(); err != nil {
		return nil, fmt.Errorf("TLS configuration: %w", err)
	}

	a := &App{
		cfg:                cfg,
		tmpl:               tmpl,
		mux:                http.NewServeMux(),
		zfs:                zfsService,
		snapshotPolicy:     policyStore,
		jobManager:         jobMgr,
		scheduler:          scheduler,
		authService:        authService,
		userStore:          userStore,
		auditStore:         auditStore,
		smbStore:           smbStore,
		nfsStore:           nfsStore,
		iscsiStore:         iscsiStore,
		database:           database,
		smbService:         smbService,
		nfsService:         nfsService,
		iscsiService:       iscsiService,
		metricsCollector:   metricsCollector,
		startTime:          startTime,
		backupService:      backupService,
		maintenanceService: maintenanceService,
		tlsConfig:          tlsConfig,
	}

	// Start snapshot scheduler (runs every 15 minutes)
	scheduler.Start(15 * time.Minute)

	a.routes()
	return a, nil
}

func (a *App) Router() http.Handler {
	// Middleware chain order (outer to inner):
	// 1. HTTPS enforcement (redirect HTTP to HTTPS)
	// 2. CORS (handles preflight)
	// 3. Compression (gzip)
	// 4. Security headers
	// 5. Request size limit (10MB)
	// 6. Content-Type validation
	// 7. Rate limiting
	// 8. Caching (for GET requests)
	// 9. Error recovery
	// 10. Request ID
	// 11. Logging
	// 12. Audit
	// 13. Authentication
	// 14. Maintenance mode (blocks operations during maintenance)
	// 15. Routes
	return a.httpsEnforcementMiddleware(
		a.corsMiddleware(
			a.compressionMiddleware(
				a.securityHeadersMiddleware(
					a.requestSizeMiddleware(10 * 1024 * 1024)(
						a.validateContentTypeMiddleware(
							a.rateLimitMiddleware(
								a.cacheMiddleware(
									a.errorMiddleware(
										requestID(
											logging(
												a.auditMiddleware(
													a.maintenanceMiddleware(
														a.authMiddleware(a.mux),
													),
												),
											),
										),
									),
								),
							),
						),
					),
				),
			),
		),
	)
}

// StopScheduler stops the snapshot scheduler (for graceful shutdown)
func (a *App) StopScheduler() {
	if a.scheduler != nil {
		a.scheduler.Stop()
	}
	// Close database connection if present
	if a.database != nil {
		a.database.Close()
	}
}

// routes() is now in routes.go

func parseTemplates(dir string) (*template.Template, error) {
	pattern := filepath.Join(dir, "*.html")
	files, err := filepath.Glob(pattern)
	if err != nil {
		return nil, err
	}
	// Allow empty templates for testing
	if len(files) == 0 {
		// Return empty template instead of error for testing
		return template.New("root"), nil
	}

	funcs := template.FuncMap{
		"nowRFC3339": func() string { return time.Now().Format(time.RFC3339) },
	}

	t := template.New("root").Funcs(funcs)
	return t.ParseFiles(files...)
}