potomark-bot-rb/bot.rb

require 'dotenv/load'
require 'discordrb'

bot = Discordrb::Bot.new token: ENV['DISCORD_TOKEN']

BOOKMARK_EMOJI = '🔖'
PIN_EMOJI = '📌'

TRIM_MESSAGE_LENGTH = 500

bot.reaction_add do |event|
  next unless [BOOKMARK_EMOJI, PIN_EMOJI].include? event.emoji.name

  if(event.emoji.name == BOOKMARK_EMOJI)
    # extract data of the message's author
    message_author = event.message.author
    message_author_pfp = message_author.avatar_url 'png'
    message_author_nickname = message_author.display_name
    message_author_distinct = message_author.distinct

    message_author_fname = "#{message_author_nickname} (#{message_author_distinct})" # this is the 'author' field of the embed

    trimmed_msg = "#{event.message.content[0..TRIM_MESSAGE_LENGTH]}#{'...' if event.message.content.length > TRIM_MESSAGE_LENGTH}" # trim the string to TRIM_MESSAGE_LENGTH chars max to not make the embed too huge
    original_msg_link = event.message.link

    pm = event.user.pm

    pm.send_embed 'Bookmark created!' do |embed|
      embed.title = 'Go to message'
      embed.url = original_msg_link
      embed.author = Discordrb::Webhooks::EmbedAuthor.new(icon_url: message_author_pfp, name: message_author_fname)
      embed << Discordrb::Webhooks::EmbedField.new(name: 'Message (trimmed)', value: trimmed_msg)
      embed.timestamp = event.message.timestamp
    end
  end

  if(event.emoji.name == PIN_EMOJI)
    event.message.pin
  end

  nil # `event` is of type Respondable, so the return line of the block needs to be nil to prevent the bot sending something in the chhannel the reaction occured.
end

bot.reaction_remove do |event|
  next unless event.emoji.name == PIN_EMOJI
  event.message.unpin
  nil
end

bot.run