1 files changed, 72 insertions, 0 deletions
diff --git a/lib/irc/parser/numeric.ex b/lib/irc/parser/numeric.ex
new file mode 100644
index 0000000..3a6e27f
--- /dev/null
+++ b/lib/irc/parser/numeric.ex
@@ -0,0 +1,72 @@
+defmodule Irc.Parser.Numeric do
+  require Logger
+
+  @moduledoc """
+  Helpers for using IRC Numerics.
+
+  * Use macros to translate from `rpl_MOTDSTART` (a macro is generated for every numeric name).
+  * Convert a numeric to its name (name_numeric())
+  * Convert a name to its numeric (to_numeric())
+  * Check if a numeric is an error (error_numeric?())
+
+  """
+
+  defmacro __using__(_) do
+    quote do
+      require Irc.Numeric
+      import Irc.Numeric
+    end
+  end
+
+  @numerics File.read!(Path.join(:code.priv_dir(:irc), "numerics.txt"))
+  |> String.split("\n")
+  |> Enum.map(fn(line) ->
+    case String.split(String.trim(line), " ", parts: 2) do
+      ["#"<>_, _] -> nil
+      ["#"<>_] -> nil
+      [numeric, full_name = "ERR_" <> name] -> {numeric, name, true, full_name}
+      [numeric, full_name = "RPL_" <> name] -> {numeric, name, false, full_name}
+      line ->
+        Logger.debug "Invalid line in numeric.txt: #{inspect line}"
+    end
+  end)
+  |> Enum.filter(fn(n) -> n end)
+
+  for {num, name, error, full_name} <- @numerics do
+    prefix = if error, do: "err_", else: "rpl_"
+    fname = "#{prefix}#{name}" |> String.to_atom()
+
+    defmacro unquote(fname)() do
+      unquote(num)
+    end
+
+    def error_numeric?(unquote(num)) do
+      unquote(error)
+    end
+    def error_numeric?(unquote(name)) do
+      unquote(error)
+    end
+    def error_numeric?(unquote(full_name)) do
+      unquote(error)
+    end
+
+    def name_numeric(unquote(num)) do
+      unquote(full_name)
+    end
+
+    def to_numeric(unquote(num)) do
+      unquote(num)
+    end
+    def to_numeric(unquote(name)) do
+      unquote(num)
+    end
+    def to_numeric(unquote(fname)) do
+      unquote(num)
+    end
+    def to_numeric(unquote(full_name)) do
+      unquote(num)
+    end
+
+  end
+
+end