handler/src/commands.ts

import { ClientEvents } from 'discord.js';
import { CommandType, EventType, PluginType } from './core/structures';
import { AnyEventPlugin, Plugin } from './types/plugin';
import { CommandModule, EventModule, InputCommand, InputEvent } from './types/module';
import { partition } from './core/functions';
import { filename, filePath } from './core/module-loading';
import { Awaitable } from './types/handler';
export const sernMeta = Symbol('@sern/meta');
const appBitField = 0b000000011111;
/*
 * Generates a number based on CommandType.
 * This corresponds to an ApplicationCommandType or ComponentType
 * TextCommands are 0 as they aren't either or.
 */
function apiType(t: CommandType) {
    if (t === CommandType.Both || t === CommandType.Modal) return 1;
    const log = Math.log2(t);
    return (appBitField & t) !== 0 ? log : log - 2;
}

/*
 * Generates an id based on CommandType.
 * A is for any ApplicationCommand. C is for any ComponentCommand
 * Then, another number generated by apiType function is appended
 */
function uniqueId(t: CommandType) {
    const am = (appBitField & t) !== 0 ? 'A' : 'C';
    return am + apiType(t);
}

/**
 * @since 1.0.0 The wrapper function to define command modules for sern
 * @param mod
 */
export function commandModule(mod: InputCommand): CommandModule {
    const [onEvent, plugins] = partition(
        mod.plugins ?? [],
        el => (el as Plugin).type === PluginType.Control,
    );
    const fullPath = filePath();
    const name = mod.name ?? filename(fullPath);
    return {
        ...mod,
        description: mod.description ?? '...',
        name,
        onEvent,
        plugins,
        [sernMeta]: {
            id: `${name}__${uniqueId(mod.type)}`,
            fullPath,
        },
    } as CommandModule;
}
/**
 * @since 1.0.0
 * The wrapper function to define event modules for sern
 * @param mod
 */
export function eventModule(mod: InputEvent): EventModule {
    const [onEvent, plugins] = partition(
        mod.plugins ?? [],
        el => (el as Plugin).type === PluginType.Control,
    );
    const fullPath = filePath();
    return {
        name: mod.name ?? filename(fullPath),
        onEvent,
        plugins,
        [sernMeta]: {
            id: 'no-id',
            fullPath,
        },
        ...mod,
    } as EventModule;
}

/** Create event modules from discord.js client events,
 * This is an {@link eventModule} for discord events,
 * where typings can be very bad.
 * @Experimental
 * @param mod
 */
export function discordEvent<T extends keyof ClientEvents>(mod: {
    name: T;
    plugins?: AnyEventPlugin[];
    execute: (...args: ClientEvents[T]) => Awaitable<unknown>;
}) {
    return eventModule({
        type: EventType.Discord,
        ...mod,
    });
}