discord nick handling

lib/discordhandler.ex

@@ -8,7 +8,9 @@ defmodule Discordirc.DiscordHandler do
   end
 
   def handle_event({:MESSAGE_CREATE, msg, _ws_state}) do
-    unless msg.author.username == "discord-irc" and msg.author.discriminator == "8465" do
+    {:ok, me} = Api.get_current_user()
+
+    unless msg.author.username == me.username and msg.author.discriminator == me.discriminator do
       case ChannelMap.irc(msg.channel_id) do
         {:ok, net, _} ->
           pid = String.to_atom(net)

lib/formatter.ex

@@ -1,4 +1,6 @@
 defmodule Discordirc.Formatter do
+  alias Nostrum.Api, as: DiscordAPI
+
   def from_irc(nick, msg) do
     from_irc(nick, msg, false)
   end
@@ -26,16 +28,109 @@ defmodule Discordirc.Formatter do
     end
   end
 
+  defmodule DiscordUserInfo do
+    defstruct id: nil, username: nil, discriminator: nil, nickname: nil
+
+    def from_id(id) do
+      {:ok, user} = DiscordAPI.get_user(id)
+      # currently we'll just use the first guild we're connected to to resolve nicks.
+      # TODO: implement mutli-guild functionality
+      g = DiscordAPI.get_current_user_guilds!() |> List.first()
+      {:ok, member} = DiscordAPI.get_guild_member(g.id(), user.id())
+
+      %DiscordUserInfo{
+        id: id,
+        username: user.username,
+        discriminator: user.discriminator,
+        nickname: member.nick
+      }
+    end
+  end
+
+  def tryreplace(s, m) do
+    pattern = ~r/\<\@\!(\d+)\>/um
+    dui = m[:dui]
+    r = m[:str]
+
+    if String.match?(s, pattern) do
+      if s == r do
+        if is_binary(dui.nickname) do
+          String.replace(s, r, dui.nickname)
+        else
+          String.replace(s, r, dui.username <> "#" <> dui.discriminator)
+        end
+      else
+        nil
+      end
+    else
+      s
+    end
+  end
+
+  def doallreplacements(split, matches, acc) do
+    [shead | stail] = split
+    {str, [m | mtail]} = acc
+
+    s = tryreplace(shead, m)
+
+    if is_nil(s) do
+      doallreplacements(split, matches, {str, mtail})
+    else
+      if stail == [] do
+        str <> s
+      else
+        doallreplacements(stail, matches, {str <> s, matches})
+      end
+    end
+  end
+
+  def fixdiscordidstrings(content, bare \\ false) do
+    pattern = ~r/\<\@\!(\d+)\>/um
+
+    matches =
+      Regex.scan(pattern, content)
+      |> Enum.uniq()
+      |> Enum.map(fn x ->
+        [
+          str: List.first(x),
+          id: List.last(x),
+          dui: DiscordUserInfo.from_id(String.to_integer(List.last(x)))
+        ]
+      end)
+
+    unless matches == [] do
+      if bare do
+        doallreplacements(
+          Regex.split(pattern, content, include_captures: true),
+          matches,
+          {"", matches}
+        )
+      else
+        doallreplacements(
+          Regex.split(pattern, content, include_captures: true),
+          matches,
+          {"@", matches}
+        )
+      end
+    else
+      content
+    end
+  end
+
   def from_discord(user, msg) do
     usr = "#{user.username}\##{user.discriminator}"
-    messages = String.split(msg, "\n")
+
+    messages =
+      msg
+      |> String.split("\n")
+      |> Enum.map(&fixdiscordidstrings(&1))
 
     # discord may give... many lines. split and format.
     case Enum.count(messages) do
       0 ->
         "<#{usr}> #{messages[0]}"
 
-      x ->
+      _ ->
         messages
         |> Enum.map(fn m -> "<#{usr}> #{m}" end)
     end