import type { APIMessageComponentEmoji } from "discord.js";

const CUSTOM_EMOJI_RE = /^<(?<animated>a?):(?<name>[A-Za-z0-9_]+):(?<id>\d+)>$/;

export function parseColor(input: string): number | undefined {
  const trimmed = input.trim();
  if (!trimmed) return undefined;
  const normalized = trimmed.startsWith("#") ? trimmed.slice(1) : trimmed;
  if (!/^[0-9a-fA-F]{6}$/.test(normalized)) return undefined;
  return Number.parseInt(normalized, 16);
}

export function formatColor(color?: number): string {
  if (color === undefined) return "Not set";
  return `#${color.toString(16).padStart(6, "0").toUpperCase()}`;
}

export function customEmojiId(input?: string): string | undefined {
  if (!input) return undefined;
  return input.trim().match(CUSTOM_EMOJI_RE)?.groups?.id;
}

export function emojiForButton(input?: string): APIMessageComponentEmoji | string | undefined {
  if (!input?.trim()) return undefined;
  const emoji = input.trim();
  const match = emoji.match(CUSTOM_EMOJI_RE);
  if (!match?.groups) return emoji;
  return {
    id: match.groups.id,
    name: match.groups.name,
    animated: match.groups.animated === "a",
  };
}

export function reactionEmojiKey(name: string | null, id: string | null, animated = false): string {
  if (id && name) return `<${animated ? "a" : ""}:${name}:${id}>`;
  return name ?? "";
}

export function emojiMatches(storedEmoji: string | undefined, reactionName: string | null, reactionId: string | null): boolean {
  if (!storedEmoji) return false;
  const stored = storedEmoji.trim();
  const reactionKey = reactionEmojiKey(reactionName, reactionId);
  if (stored === reactionKey) return true;
  if (reactionId && customEmojiId(stored) === reactionId) return true;
  return stored === (reactionName ?? "");
}