1 files changed, 76 insertions, 1 deletions
diff --git a/shard/lib/app/chat.ex b/shard/lib/app/chat.ex
index 8c55869..be3b848 100644
--- a/shard/lib/app/chat.ex
+++ b/shard/lib/app/chat.ex
@@ -31,6 +31,10 @@ defmodule SApp.Chat do
   # =========
 
   defmodule Manifest do
+    @moduledoc"""
+    Manifest for a public chat room defined by its name.
+    """
+
     defstruct [:channel]
   end
 
@@ -42,8 +46,17 @@ defmodule SApp.Chat do
 
 
   defmodule PrivChat.Manifest do
+    @moduledoc"""
+    Manifest for a private chat room defined by the list of participants.
+
+    Do not instanciate this struct directly, use `new` to ensure a canonical representation.
+    """
+
     defstruct [:pk_list]
 
+    @doc"""
+    Ensures a canonical representation by sorting pks and removing duplicates.
+    """
     def new(pk_list) do
       %__MODULE__{pk_list: pk_list |> Enum.sort |> Enum.uniq}
     end
@@ -322,7 +335,7 @@ defmodule SApp.Chat do
     end
   end
 
-  def msg_cmp({pk1, msgbin1, _sign1}, {pk2, msgbin2, _sign2}) do
+  defp msg_cmp({pk1, msgbin1, _sign1}, {pk2, msgbin2, _sign2}) do
     {ts1, msg1} = SData.term_unbin msgbin1
     {ts2, msg2} = SData.term_unbin msgbin2
     cond do
@@ -335,4 +348,66 @@ defmodule SApp.Chat do
       true -> :duplicate
     end
   end 
+
+  # ================
+  # PUBLIC INTERFACE
+  # ================
+  
+  @doc"""
+  Subscribe to notifications for this chat room.
+
+  The process calling this function will start recieving messages of the form:
+
+    {:chat_recv, manifest, {pk, msgbin, sign}}
+
+  or
+
+    {:chat_send, manifest, {pk, msgbin, sign}}
+
+  msgbin can be used in the following way:
+
+    {timestamp, message} = SData.term_unbin msgbin
+  """
+  def subscribe(shard_pid) do
+    GenServer.cast(shard_pid, {:subscribe, self()})
+  end
+
+  @doc"""
+  Send a message to a chat room.
+  """
+  def chat_send(shard_pid, pk, msg) do
+    GenServer.cast(shard_pid, {:chat_send, pk, msg})
+  end
+
+  @doc"""
+  Read the history of a chat room.
+
+  The second argument is the last message to read.
+  If nil, will read the n last messages.
+  If not nill, will read the n last messages until the specified bound.
+  """
+  def read_history(shard_pid, bound, n) do
+    GenServer.call(shard_pid, {:read_history, bound, n})
+  end
+
+  @doc"""
+  Return a shard's manifest from its pid.
+  """
+  def get_manifest(shard_pid) do
+    GenServer.call(shard_pid, :manifest)
+  end
+
+  @doc"""
+  Returns timestamp of last message if chat room has unread messages, nil otherwise.
+  """
+  def has_unread?(shard_pid) do
+    GenServer.call(shard_pid, :has_unread)
+  end
+
+  @doc"""
+  Mark all messages as read
+  """
+  def mark_read(shard_pid) do
+    GenServer.cast(shard_pid, :mark_read)
+  end
 end