csharp-api.md

Bannerlord Expanded Template C# API

The Bannerlord Expanded Template C# API provides interfaces and classes to initialize the API with custom logging. Currently, the API is quite limited and primarily designed for initialization. If there is a demand for a more advanced API that interacts with the mod's data, we will consider implementing such use cases in future updates.

Initializing the Expanded Template

To initialize the expanded template, use the BannerlordExpandedTemplateApi class. This class is responsible for bootstrapping the module and injecting any required sub-modules.

Example:

public class MySubModule : MBSubModuleBase
{
    public MySubModule()
    {
        new BannerlordExpandedTemplateApi().Bind();
    }
}

Logging API

The mod will log a number of information to help you debug issues such as empty equipment templates resulting in "nude" soldiers. By implementing a custom logger and logger factory, you can control how and where log messages are handled.

Logger Interface (ILogger)

The ILogger interface provides methods for different log levels:

• Debug(string message)
• Info(string message)
• Warn(string message)
• Error(string message, Exception? exception = null)
• Fatal(string message, Exception? exception = null)

Example: Custom Logger

You can create your own logger by implementing the ILogger interface:

public class ExpandedTemplateApiLogger : ILogger
{
    public void Debug(string message)
    {
        // Handle debug-level logging
        Console.WriteLine($"[DEBUG] {message}");
    }

    public void Info(string message) 
    {
        // Handle info-level logging
        Console.WriteLine($"[INFO] {message}");
    }

    public void Warn(string message) 
    {
        // Handle warnings
        Console.WriteLine($"[WARN] {message}");
    }

    public void Error(string message, Exception? exception = null) 
    {
        // Handle errors
        Console.WriteLine($"[ERROR] {message}, Exception: {exception?.Message}");
    }

    public void Fatal(string message, Exception? exception = null) 
    {
        // Handle fatal errors
        Console.WriteLine($"[FATAL] {message}, Exception: {exception?.Message}");
    }
}

Logger Factory (ILoggerFactory)

The ILoggerFactory interface allows you to define a factory that creates loggers for your mod. This is useful when you want to centralize your logging logic.

Example: Custom Logger Factory

Here is how you can implement a LoggerFactory to return instances of your custom logger:

public class MyLoggerFactory : ILoggerFactory
{
    public ILogger CreateLogger<T>()
    {
        return new ExpandedTemplateApiLogger(); // Return your custom logger implementation
    }
}

Using a Custom Logger with the API

Once you have implemented your custom logger and logger factory, you can use them with the BannerlordExpandedTemplateApi.

new BannerlordExpandedTemplateApi()
    .UseLoggerFactory(new MyLoggerFactory())
    .Bind();

Alternative: Logger Decorator

If you want to decorate or wrap an existing logger with additional functionality, you can use the decorator pattern. Here is an example:

public class ExpandedTemplateApiLogger : ILogger
{
    private readonly MyLogger _logger;

    public ExpandedTemplateApiLogger(MyLogger logger) 
    {
        _logger = logger;
    }

    public void Debug(string message) 
    {
        _logger.Debug(message);
    }

    public void Info(string message) 
    {
        _logger.Info(message);
    }

    public void Warn(string message) 
    {
        _logger.Warn(message);
    }

    public void Error(string message, Exception? exception = null) 
    {
        _logger.Error(message, exception);
    }

    public void Fatal(string message, Exception? exception = null) 
    {
        _logger.Fatal(message, exception);
    }
}