> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/korrykatti/game/llms.txt
> Use this file to discover all available pages before exploring further.

# Joining a game

> Connect to a hosted game as a client

To join a multiplayer game, a player must connect to an existing server using the `SetupClient()` function. This establishes a connection to the host and allows both players to begin the match.

## How joining works

<Steps>
  <Step title="Create the client host">
    First, create a client-side ENet host:

    ```cpp main.cpp theme={null}
    clientHost = enet_host_create(
        NULL,  // create a client host
        1,     // only 1 outgoing connection
        2,     // allow up to 2 channels
        0,     // unlimited download bandwidth
        0      // unlimited upload bandwidth
    );
    ```

    Passing `NULL` as the first parameter creates a client host that can initiate connections but not accept them.
  </Step>

  <Step title="Verify client creation">
    Check if the client host was created successfully:

    ```cpp main.cpp theme={null}
    if (clientHost == NULL){
        printf("failed to create client host\n");
        return false;
    }
    ```

    If creation fails, the game returns to the main menu.
  </Step>

  <Step title="Configure server address">
    Set up the address of the server to connect to:

    ```cpp main.cpp theme={null}
    ENetAddress address;
    enet_address_set_host(&address, SERVER_IP);
    address.port = SERVER_PORT;
    ```

    The `enet_address_set_host()` function resolves the hostname or IP address (by default "127.0.0.1") to an ENet address.
  </Step>

  <Step title="Connect to the server">
    Initiate the connection to the server:

    ```cpp main.cpp theme={null}
    serverPeer = enet_host_connect(clientHost,
        &address,  
        2,  // number of channels
        0   // user data
    );
    if (serverPeer == NULL){
        printf("failed to connect to server");
        return false;
    }
    printf("Connecting to %s:%d...\n",SERVER_IP,SERVER_PORT);
    return true;
    ```

    This returns a peer object representing the connection to the server.
  </Step>

  <Step title="Wait for connection confirmation">
    The game enters the `JOINING` state and waits for the connection to be established:

    ```cpp main.cpp theme={null}
    ENetEvent event;
    while (enet_host_service(clientHost, &event, 0) > 0) {
        if (event.type == ENET_EVENT_TYPE_CONNECT) {
            printf("Connected to server!\n");
            connectionState = "CONNECTED";
            
            // Start the game
            state = "MULTIPLAYER";
        }
    }
    ```

    Once the connection is confirmed, the game transitions to the multiplayer gameplay state.
  </Step>
</Steps>

## Complete SetupClient function

```cpp main.cpp theme={null}
bool SetupClient() {
    // create a client host
    clientHost = enet_host_create(
        NULL,
        1,
        2,
        0,
        0
    );
    if (clientHost == NULL){
        printf("failed to create client host\n");
        return false;
    }

    ENetAddress address;
    enet_address_set_host(&address, SERVER_IP);
    address.port = SERVER_PORT;

    serverPeer = enet_host_connect(clientHost,
        &address,  
        2,
        0
    );
    if (serverPeer == NULL){
        printf("failed to connect to server");
        return false;
    }
    printf("Connecting to %s:%d...\n",SERVER_IP,SERVER_PORT);
    return true;
}
```

## Network variables

The following global variables manage the client connection:

```cpp main.cpp theme={null}
ENetHost* clientHost = nullptr;
ENetPeer* serverPeer = nullptr; // for client connection to server
```

<Note>
  When joining, the client uses `clientHost` to manage its networking and stores the server connection in `serverPeer`.
</Note>

## Connection to localhost vs LAN

By default, the game connects to `127.0.0.1` (localhost), which only works if both players are on the same machine.

For LAN play, modify the `SERVER_IP` constant to the host's local network IP address:

```cpp main.cpp theme={null}
const char* SERVER_IP = "192.168.1.100"; // Replace with host's IP
```

<Warning>
  Ensure both players are on the same network and the host's firewall allows incoming connections on port 7777.
</Warning>

## Troubleshooting

If connection fails:

* Verify the server is running and in the `HOSTING` state
* Check that `SERVER_IP` points to the correct host address
* Ensure port 7777 is not blocked by firewall rules
* Confirm ENet has been initialized before calling `SetupClient()`