Build a Discord Price Check Bot

const { Client, GatewayIntentBits, EmbedBuilder } = require("discord.js");

const DISCORD_TOKEN = process.env.DISCORD_TOKEN;
const API_BASE = "https://api.tcgapi.dev/v1";
const API_KEY = process.env.TCG_API_KEY;
const headers = { "X-API-Key": API_KEY };

const client = new Client({ intents: [GatewayIntentBits.Guilds] });

// Helper: fetch card price from TCG API
async function lookupCard(query, game) {
  const params = new URLSearchParams({ q: query, limit: "1" });
  if (game) params.set("game", game);

  const searchRes = await fetch(`${API_BASE}/search?${params}`, { headers });
  const { results } = await searchRes.json();

  if (!results || results.length === 0) return null;

  const card = results[0];
  const priceRes = await fetch(`${API_BASE}/cards/${card.id}/prices`, { headers });
  const prices = await priceRes.json();

  return { ...card, prices };
}

// Helper: format price with trend arrow
function formatTrend(changePercent) {
  if (changePercent == null) return "";
  const arrow = changePercent > 0 ? "\u2B06" : changePercent < 0 ? "\u2B07" : "\u27A1";
  return `${arrow} ${changePercent > 0 ? "+" : ""}${changePercent.toFixed(1)}%`;
}

// Handle /price command
async function handlePrice(interaction) {
  const query = interaction.options.getString("card");
  const game = interaction.options.getString("game");

  await interaction.deferReply();

  const result = await lookupCard(query, game);

  if (!result) {
    await interaction.editReply(`No results found for "${query}".`);
    return;
  }

  const { prices } = result;
  const embed = new EmbedBuilder()
    .setTitle(result.name)
    .setDescription(`**${result.set_name}** · ${result.game_name}`)
    .setColor(0x6366f1)
    .addFields(
      {
        name: "Market Price",
        value: prices.market_price
          ? `$${prices.market_price.toFixed(2)}`
          : "N/A",
        inline: true,
      },
      {
        name: "Low Price",
        value: prices.low_price
          ? `$${prices.low_price.toFixed(2)}`
          : "N/A",
        inline: true,
      },
      {
        name: "Foil Market",
        value: prices.foil_market_price
          ? `$${prices.foil_market_price.toFixed(2)}`
          : "N/A",
        inline: true,
      },
      {
        name: "24h",
        value: formatTrend(prices.change_24h) || "—",
        inline: true,
      },
      {
        name: "7d",
        value: formatTrend(prices.change_7d) || "—",
        inline: true,
      },
      {
        name: "30d",
        value: formatTrend(prices.change_30d) || "—",
        inline: true,
      }
    )
    .setFooter({ text: "Data from TCG API · tcgapi.dev" })
    .setTimestamp();

  if (result.image_url) embed.setThumbnail(result.image_url);

  await interaction.editReply({ embeds: [embed] });
}

// Handle /trending command
async function handleTrending(interaction) {
  const game = interaction.options.getString("game") || "pokemon";

  await interaction.deferReply();

  const res = await fetch(
    `${API_BASE}/prices/top-movers?game=${game}&period=24h&limit=5`,
    { headers }
  );
  const { gainers, losers } = await res.json();

  const formatList = (cards) =>
    cards
      .map(
        (c, i) =>
          `${i + 1}. **${c.name}** — $${c.market_price.toFixed(2)} (${
            c.change_pct > 0 ? "+" : ""
          }${c.change_pct.toFixed(1)}%)`
      )
      .join("\n");

  const embed = new EmbedBuilder()
    .setTitle(`Trending Cards — ${game.charAt(0).toUpperCase() + game.slice(1)}`)
    .setColor(0x6366f1)
    .addFields(
      { name: "\u2B06 Top Gainers (24h)", value: formatList(gainers) || "None" },
      { name: "\u2B07 Top Losers (24h)", value: formatList(losers) || "None" }
    )
    .setFooter({ text: "Data from TCG API · tcgapi.dev" })
    .setTimestamp();

  await interaction.editReply({ embeds: [embed] });
}

// Route slash commands
client.on("interactionCreate", async (interaction) => {
  if (!interaction.isChatInputCommand()) return;

  try {
    if (interaction.commandName === "price") await handlePrice(interaction);
    if (interaction.commandName === "trending") await handleTrending(interaction);
  } catch (err) {
    console.error(err);
    const reply = { content: "Something went wrong. Try again in a moment.", ephemeral: true };
    interaction.deferred
      ? await interaction.editReply(reply)
      : await interaction.reply(reply);
  }
});

client.login(DISCORD_TOKEN);

const { REST, Routes, SlashCommandBuilder } = require("discord.js");

const commands = [
  new SlashCommandBuilder()
    .setName("price")
    .setDescription("Look up a card's current market price")
    .addStringOption(opt =>
      opt.setName("card").setDescription("Card name to search for").setRequired(true)
    )
    .addStringOption(opt =>
      opt.setName("game").setDescription("Filter by game (e.g. pokemon, magic, yugioh)")
    ),

  new SlashCommandBuilder()
    .setName("trending")
    .setDescription("Show top price movers for a game")
    .addStringOption(opt =>
      opt.setName("game").setDescription("Game to check (default: pokemon)")
    ),
];

const rest = new REST().setToken(process.env.DISCORD_TOKEN);

(async () => {
  await rest.put(
    Routes.applicationCommands(process.env.DISCORD_APP_ID),
    { body: commands.map(c => c.toJSON()) }
  );
  console.log("Slash commands registered.");
})();