# DEFINING GLOBAL TYPES To ensure Type Safety throughout the application and allow the [**TypeScript**](https://www.typescriptlang.org/) compiler to recognize the new global authentication functions (such as `handleLogin` and `handleRegister`), we must extend the global type declarations. ### Implementation Open the file `web/src/types.d.ts` and add the following type declarations starting from `handleLogin` down to `useSignOut`. These definitions inform **TypeScript** about the existence, arguments, and return types of these functions, preventing compilation errors in the views and hooks. {% code overflow="wrap" lineNumbers="true" %} ```typescript declare function handleLogin( username: string, password: string ): Promise<{ success: boolean; message: string; }>; declare function handleRegister( username: string, password: string, accountData: unknown, ): Promise<{ success: boolean; message: string; }>; declare function useCurrentUser(): { username: string; accountData: unknown } | null; declare function useIsAuthenticated(): boolean; declare function useSignOut(): void; ``` {% endcode %} {% hint style="info" %} ***Note**: The existing utility declarations (e.g., `openGalleryPicker`, `startCall`, `useSettings`, etc.) already present in `types.d.ts` should remain untouched. You only need to append the new authentication declarations listed above.* {% endhint %} ### Functions Reference #### `handleLogin` ```typescript const response = await handleLogin( 'username', 'password' ); console.log(response); ``` **Arguments**
NameTypeOptionalDescription
usernamestring❌The username to attempt login with.
passwordstring❌The user's password.
**Returns**
NameTypeDescription
successbooleanThe success boolean is true upon success.
messagestringThe message string provides an error description (if unsuccessful) or a confirmation message.
#### `handleRegister` **Example** ```typescript const response = await handleRegister( 'newuser', 'securepassword', { email: 'test@example.com', age: 30 } ); console.log(response); ``` **Arguments**
NameTypeOptionalDescription
usernamestring❌The username for the new registration.
passwordstring❌The new user's password.
accountDataunknown✅Optional additional account data to be saved (e.g., email, date of birth). Can be null.
**Returns**
NameTypeDescription
successbooleanThe success boolean is true upon success.
messagestringThe message string provides an error description (if unsuccessful) or a confirmation message.
#### `useCurrentUser` **Example** ```typescript const user = useCurrentUser(); if (user) { console.log(`Logged in as: ${user.username}`); } ``` **Returns**
NameTypeDescription
usernamestringCurrent login username
accountDataunknownReturn data provided while registering