Pylon Starboard

// React with :star: to any message and it will send this message in a special channel.
// When a reaction is removed or added, it will update the message (or delete it if the last :star: was removed)

const starboardChannelID = '696276355893035008';
const star = '⭐';

async function handleReaction(
  data: discord.Event.IMessageReactionAdd | discord.Event.IMessageReactionRemove
) {
  // Ignore event if reaction emoji is not a star
  if (data.emoji.name !== star) return;

  // Get the message ID of starboard message
  const starboardMessageID = <string | undefined>(
    await pylon.kv.get(data.messageId)
  );

  // Get the original channel and check if it is a text channel, so we can get the originalMessage
  const originalChannel = await discord.getChannel(data.channelId);
  if (!(originalChannel instanceof discord.GuildTextChannel)) {
    return;
  }

  // Get the original message and check if it exists
  const originalMessage = await originalChannel.getMessage(data.messageId);
  if (!originalMessage) {
    return;
  }

  // Get the starboard channel and check if it is a text channel, so we can get or send the starboard message
  const starboardChannel = await discord.getChannel(starboardChannelID);
  if (!(starboardChannel instanceof discord.GuildTextChannel)) {
    return;
  }

  const stars = originalMessage.reactions.filter((v) => v.emoji.name === star)
    .length;

  // `messageData` will be sent in the starboard channel
  const messageData = {
    content: `${stars + star} (<#${data.channelId}>)`,
    embed: {
      color: 0xffbe76,
      description: originalMessage.content,
      fields: [
        {
          name: 'Original message',
          value: `[Jump](https://discordapp.com/channels/${data.guildId}/${data.channelId}/${data.messageId})`,
          inline: false
        }
      ]
    }
  };

  if (!starboardMessageID) {
    // First star
    // Send starboard message and store the message ID in KV

    const msg = await starboardChannel.sendMessage(messageData);
    await pylon.kv.put(data.messageId, msg.id);
  } else {
    // Not the first star
    // Just get and edit the starboard message

    const starboardMessage = await starboardChannel.getMessage(
      starboardMessageID
    );

    // Check if the message still exists...
    if (!starboardMessage) {
      return;
    }

    // Delete the starboard message if there are no stars
    if (stars === 0) {
      await starboardMessage.delete();
      await pylon.kv.delete(data.messageId);
    } else {
      // Update the starboard message
      await starboardMessage.edit(messageData);
    }
  }
}

// Register events
discord.registerEventHandler('MESSAGE_REACTION_ADD', handleReaction);

discord.registerEventHandler('MESSAGE_REACTION_REMOVE', handleReaction);