import "reflect-metadata";
import { Message, PermissionFlags, type PermissionString } from "@fluxerjs/core";
import { GetMemeberPermission } from "@/utils";

export interface RequireUserPermissionMeta {
  permissions: PermissionString[];
  mode?: "all" | "any";
}

export const GUARDS_KEY = Symbol("fluxer:guards");
export type Guard = (msg: Message) => boolean | Promise<boolean>;

export function RequireNonBot(): Guard {
  return (msg) => !msg.author.bot;
}

export function RequirePrefix(prefix: string): Guard {
  return (msg) => msg.content.startsWith(prefix);
}

export function RequireUserPermission(meta: RequireUserPermissionMeta): Guard {
  return async (msg) => {
    const permission = await GetMemeberPermission(msg);
    if (permission === null) return false;
    const check = meta.mode === "any" ? "some" : "every";
    return meta.permissions[check]((flag) => permission.has(PermissionFlags[flag]));
  };
}

export function RequireGuild(): Guard {
  return (msg) => msg.guild !== null;
}

export function RequireNonBotDecorator(): ClassDecorator {
  return (target) => {
    const guards: Guard[] = Reflect.getMetadata(GUARDS_KEY, target) ?? [];
    guards.push(RequireNonBot());
    Reflect.defineMetadata(GUARDS_KEY, guards, target);
  };
}

export function RequirePrefixDecorator(prefix: string): ClassDecorator {
  return (target) => {
    const guards: Guard[] = Reflect.getMetadata(GUARDS_KEY, target) ?? [];
    guards.push(RequirePrefix(prefix));
    Reflect.defineMetadata(GUARDS_KEY, guards, target);
  };
}

export function RequireUserPermissionDecorator(meta: RequireUserPermissionMeta): ClassDecorator {
  return (target) => {
    const guards: Guard[] = Reflect.getMetadata(GUARDS_KEY, target) ?? [];
    guards.push(RequireUserPermission(meta));
    Reflect.defineMetadata(GUARDS_KEY, guards, target);
  };
}

export function RequireGuildDecorator(): ClassDecorator {
  return (target) => {
    const guards: Guard[] = Reflect.getMetadata(GUARDS_KEY, target) ?? [];
    guards.push(RequireGuild());
    Reflect.defineMetadata(GUARDS_KEY, guards, target);
  };
}