classDiagram
    direction LR

    class Card {
        +int ID
        +string Icon
        +string Title
        +string Subtitle
        +string URL
        +int Sort
        +bool Enabled
        +time Time CreatedAt
    }

    class Setting {
        +string Key
        +string Value
    }

    class Admin {
        +int ID
        +string Username
        +string Password
    }

    class SessionData {
        +int AdminID
        +string Username
        +time Time CreatedAt
    }

    class SessionStore {
        -map~string-SessionData~ store
        -sync.RWMutex mu
        +Create(adminID int, username string) string
        +Get(sessionID string) *SessionData
        +Delete(sessionID string)
    }

    class CardModel {
        +GetAllCards() []Card
        +GetEnabledCards() []Card
        +GetCardByID(id int) *Card
        +CreateCard(card *Card) error
        +UpdateCard(card *Card) error
        +DeleteCard(id int) error
        +ToggleCard(id int) error
        +MoveCardUp(id int) error
        +MoveCardDown(id int) error
    }

    class SettingModel {
        +GetSetting(key string) string
        +SetSetting(key string, value string) error
        +GetSearchEngines() map~string-string
        +SetSearchEngine(name string, url string) error
    }

    class AdminModel {
        +GetAdminByUsername(username string) *Admin
        +CreateAdmin(username string, password string) error
        +VerifyPassword(username string, password string) bool
        +ChangePassword(adminID int, newPassword string) error
    }

    class HandlerHome {
        +HomeHandler(c *gin.Context)
    }

    class HandlerAdmin {
        +LoginGet(c *gin.Context)
        +LoginPost(c *gin.Context)
        +Logout(c *gin.Context)
        +AdminIndex(c *gin.Context)
    }

    class HandlerCards {
        +CardsList(c *gin.Context)
        +CardCreateGet(c *gin.Context)
        +CardCreatePost(c *gin.Context)
        +CardEditGet(c *gin.Context)
        +CardEditPost(c *gin.Context)
        +CardDelete(c *gin.Context)
        +CardToggle(c *gin.Context)
        +CardMoveUp(c *gin.Context)
        +CardMoveDown(c *gin.Context)
    }

    class HandlerSettings {
        +SettingsGet(c *gin.Context)
        +SettingsPost(c *gin.Context)
    }

    class AuthMiddleware {
        +AuthRequired() gin.HandlerFunc
    }

    CardModel --> Card : returns
    SettingModel --> Setting : returns
    AdminModel --> Admin : returns
    SessionStore --> SessionData : stores
    HandlerHome --> CardModel : uses
    HandlerHome --> SettingModel : uses
    HandlerAdmin --> AdminModel : uses
    HandlerAdmin --> SessionStore : uses
    HandlerCards --> CardModel : uses
    HandlerSettings --> SettingModel : uses
    AuthMiddleware --> SessionStore : uses