/// <summary>
/// Initializes a new interpreter and discovers methods marked
/// with <see cref="CommandHandlerAttribute"/> attribute.
/// </summary>
protected CommandInterpreter()
{
var interpreters = new Dictionary <int, CommandHandler>();
var formatters = new Dictionary <Type, FormatterInfo>();
const BindingFlags publicInstanceMethod = BindingFlags.Public | BindingFlags.Instance;
foreach (var method in GetType().GetMethods(publicInstanceMethod))
{
var handlerAttr = method.GetCustomAttribute <CommandHandlerAttribute>();
if (handlerAttr is not null && method.ReturnType == typeof(ValueTask))
{
var parameters = method.GetParameterTypes();
if (GetLength(parameters) != 2 || !parameters[0].IsValueType || parameters[1] != typeof(CancellationToken))
{
continue;
}
var commandType = parameters[0];
var commandAttr = commandType.GetCustomAttribute <CommandAttribute>();
if (commandAttr is null || commandAttr.Formatter is null)
{
continue;
}
var formatter = new FormatterInfo(commandAttr);
if (formatter.IsEmpty)
{
continue;
}
var interpreter = Delegate.CreateDelegate(typeof(Func <, ,>).MakeGenericType(commandType, typeof(CancellationToken), typeof(ValueTask)), method.IsStatic ? null : this, method);
interpreters.Add(commandAttr.Id, Cast <CommandHandler>(Activator.CreateInstance(typeof(CommandHandler <>).MakeGenericType(commandType), formatter, interpreter)));
formatters.Add(commandType, formatter);
}
}
this.interpreters = CreateRegistry(interpreters);
interpreters.Clear();
formatters.TrimExcess();
this.formatters = formatters;
}