feat: Add Argument class and types.

src/classes/arguments/Argument.ts

@@ -0,0 +1,67 @@
+import {ArgumentContext} from '../contexts';
+
+type ArgumentValidator = (argument: string, ctx: ArgumentContext) => boolean;
+type ArgumentParser<T> = (argument: string, ctx: ArgumentContext) => T | null | Promise<T | null>;
+
+export type ArgumentFunction<T> = (options: ArgumentBuilder<T>) => Argument<T>;
+
+export enum ArgumentType {
+	BOOLEAN = 'boolean',
+	CHANNEL = 'channel',
+	COMMAND = 'command',
+	CHOICE = 'choice',
+	EMOJI = 'emoji',
+	ENUM = 'enum',
+	EVENT = 'event',
+	FLOAT = 'float',
+	GUILD = 'guild',
+	GUILD_MEMBER = 'guild_member',
+	INTEGER = 'integer',
+	MESSAGE = 'message',
+	REGEX = 'regex',
+	ROLE = 'role',
+	SNOWFLAKE = 'snowflake',
+	STRING = 'string',
+	TEXT_CHANNEL = 'text_channel',
+	USER = 'user',
+}
+
+type DefaultValueArgument<T> = {defaultValue: T};
+type CoalescingArgument = {coalescing: boolean};
+type OptionalArgument = {optional: boolean};
+export type ArgumentBuilder<T> = Partial<(DefaultValueArgument<T> | CoalescingArgument | OptionalArgument) & {description: string}>;
+
+export interface ArgumentOptions<T> {
+	coalescing?: boolean;
+	defaultValue?: T;
+	description?: string;
+	optional?: boolean;
+}
+
+export class Argument<T> {
+	public constructor(public type: ArgumentType, public options: ArgumentOptions<T>, public validator: ArgumentValidator, public parser: ArgumentParser<T>) {}
+}
+
+export class CommandArgument<T> {
+	public coalescing: boolean;
+	public defaultValue: T | undefined;
+	public description: string;
+	public optional: boolean;
+	public parse: ArgumentParser<T>;
+	public type: ArgumentType;
+	public validate: ArgumentValidator;
+
+	public constructor(public name: string, public index: number, argument: Argument<T>) {
+		this.validate = argument.validator;
+		this.coalescing = argument.options.coalescing ?? false;
+		this.defaultValue = argument.options.defaultValue ?? undefined;
+		this.description = argument.options.description ?? '';
+		this.optional = argument.options.optional ?? false;
+		this.type = argument.type;
+		this.parse = argument.parser;
+	}
+
+	public get isSimple() {
+		return !this.optional && !this.coalescing && !this.defaultValue;
+	}
+}