package session

import (
	"context"
	"encoding/json"
	"errors"
	"net/http"
	"time"

	"management/internal/erpserver/model/dto"
	"management/internal/pkg/config"

	"github.com/alexedwards/scs/postgresstore"
	"github.com/alexedwards/scs/v2"
	"gorm.io/gorm"
)

var ErrNoSession = errors.New("session user not found")

// Manager 抽象核心会话操作
type Manager interface {
	Load(next http.Handler) http.Handler
	GetUser(ctx context.Context, key string) (*dto.AuthorizeUser, error)
	PutUser(ctx context.Context, key string, user *dto.AuthorizeUser) error
	RenewToken(ctx context.Context) error
	Destroy(ctx context.Context) error
}

type SCSSession struct {
	manager *scs.SessionManager
}

func NewSCSManager(db *gorm.DB, config *config.Config) (Manager, error) {
	sessionManager := scs.New()
	sessionManager.Lifetime = 24 * time.Hour
	sessionManager.IdleTimeout = 2 * time.Hour
	sessionManager.Cookie.Name = "token"
	sessionManager.Cookie.HttpOnly = true
	sessionManager.Cookie.Persist = true
	sessionManager.Cookie.SameSite = http.SameSiteStrictMode
	sessionManager.Cookie.Secure = config.App.Prod

	sqlDB, err := db.DB()
	if err != nil {
		return nil, err
	}

	// postgres
	// github.com/alexedwards/scs/postgresstore
	sessionManager.Store = postgresstore.New(sqlDB)
	// pgx
	// github.com/alexedwards/scs/pgxstore
	// sessionManager.Store = pgxstore.New(pool)
	// redis
	// sessionManager.Store = newRedisStore()
	return &SCSSession{manager: sessionManager}, nil
}

func (s *SCSSession) Load(next http.Handler) http.Handler {
	return s.manager.LoadAndSave(next)
}

func (s *SCSSession) GetUser(ctx context.Context, key string) (*dto.AuthorizeUser, error) {
	data, ok := s.manager.Get(ctx, key).([]byte)
	if !ok || len(data) == 0 {
		return nil, ErrNoSession
	}

	var user dto.AuthorizeUser
	if err := json.Unmarshal(data, &user); err != nil {
		return nil, err
	}
	return &user, nil
}

func (s *SCSSession) PutUser(ctx context.Context, key string, user *dto.AuthorizeUser) error {
	data, err := json.Marshal(user)
	if err != nil {
		return err
	}
	s.manager.Put(ctx, key, data)
	return nil
}

func (s *SCSSession) RenewToken(ctx context.Context) error {
	return s.manager.RenewToken(ctx)
}

func (s *SCSSession) Destroy(ctx context.Context) error {
	return s.manager.Destroy(ctx)
}