8 files changed, 191 insertions, 47 deletions

diff --git a/lib/app/chat.ex b/lib/app/chat.ex
index 4a56085..f165514 100644
--- a/lib/app/chat.ex
+++ b/lib/app/chat.ex
@@ -1,17 +1,86 @@
 defmodule SApp.Chat do
-  def send(msg) do
+  use GenServer
+
+  def start_link(channel) do
+    GenServer.start_link(__MODULE__, channel)
+  end
+
+  def init(channel) do
+    {:ok, store} = SData.MerkleList.start_link(&msg_cmp/2)
+    manifest = {:chat, channel}
+    id = :crypto.hash(:sha256, :erlang.term_to_binary(manifest))
+
+    GenServer.cast(Shard.Manager, {:register, id, self()})
+    GenServer.cast(self(), :init_pull)
+
+    {:ok, %{channel: channel, id: id, manifest: manifest, store: store, peers: %{}}}
+  end
+
+  def handle_call(:manifest, _from, state) do
+    {:reply, state.manifest, state}
+  end
+
+  def handle_cast({:redundant, _}, _state) do
+    exit :normal
+  end
+
+  def handle_cast(:init_pull, state) do
+    GenServer.call(SNet.Manager, :get_all)
+    |> Enum.each(&(GenServer.cast(&1, {:send_msg, {:interested, [state.id]}})))
+    {:noreply, state}
+  end
+
+  def handle_cast({:chat_send, msg}, state) do
     msgitem = {(System.os_time :seconds),
                Shard.Identity.get_nickname(),
                msg}
-    GenServer.cast(SApp.Chat.Log, {:insert, msgitem})
+    GenServer.cast(state.store, {:insert, msgitem})
+
+    for {_, pid} <- state.peers do
+      push_messages(state, pid, nil, 5)
+    end
 
-    SNet.ConnSupervisor
-    |> DynamicSupervisor.which_children
-    |> Enum.each(fn {_, pid, _, _} -> GenServer.cast(pid, :init_push) end)
+    {:noreply, state}
   end
 
-  def msg_callback({ts, nick, msg}) do
-    IO.puts "#{ts |> DateTime.from_unix! |> DateTime.to_iso8601} <#{nick}> #{msg}"
+  def handle_cast({:interested, peer_id, peer_pid}, state) do
+    push_messages(state, peer_pid, nil, 10)
+    new_peers = Map.put(state.peers, peer_id, peer_pid)
+    {:noreply, %{ state | peers: new_peers }}
+  end
+
+  def handle_cast({:msg, peer_id, peer_pid, msg}, state) do
+    case msg do
+      :get_top -> push_messages(peer_id, state, nil, 10)
+      {:get, start} -> push_messages(peer_id, state, start, 20)
+      {:info, _start, list, rest} ->
+        if rest != nil and not GenServer.call(state.store, {:has, rest}) do
+          GenServer.cast(peer_pid, {:send_msg, {state.id, {:get, rest}}})
+        end
+        spawn_link(fn ->
+          Process.sleep 1000
+          GenServer.cast(state.store, {:insert_many, list, (fn msg -> msg_callback(state.channel, msg) end)})
+        end)
+    end
+
+    if Map.has_key?(state.peers, peer_id) do
+      {:noreply, state}
+    else
+      handle_cast({:interested, peer_id, peer_pid}, state)
+    end
+  end
+
+  defp push_messages(state, to, start, num) do
+    case GenServer.call(state.store, {:read, start, num}) do
+      {:ok, list, rest} ->
+        GenServer.cast(to, {:send_msg, {state.id, {:info, start, list, rest}}})
+      _ -> nil
+    end
+  end
+
+
+  def msg_callback(chan, {ts, nick, msg}) do
+    IO.puts "#{ts |> DateTime.from_unix! |> DateTime.to_iso8601}  ##{chan}  <#{nick}> #{msg}"
   end
 
   def msg_cmp({ts1, nick1, msg1}, {ts2, nick2, msg2}) do
diff --git a/lib/application.ex b/lib/application.ex
index 3ad9325..e375cf4 100644
--- a/lib/application.ex
+++ b/lib/application.ex
@@ -13,14 +13,14 @@ defmodule Shard.Application do
     # Define workers and child supervisors to be supervised
     children = [
       Shard.Identity,
+      { DynamicSupervisor, strategy: :one_for_one, name: Shard.DynamicSupervisor },
       
       # Networking
       { SNet.Manager, listen_port },
       { SNet.TCPServer, listen_port },
-      { DynamicSupervisor, strategy: :one_for_one, name: SNet.ConnSupervisor },
 
       # Applications & data store
-      { SData.MerkleList, [&SApp.Chat.msg_cmp/2, name: SApp.Chat.Log] },
+      Shard.Manager,
 
       # Web UI
       Plug.Adapters.Cowboy.child_spec(:http, SWeb.HTTPRouter, [], port: listen_port + 1000)
diff --git a/lib/cli/cli.ex b/lib/cli/cli.ex
index 28ef5d0..0402b3f 100644
--- a/lib/cli/cli.ex
+++ b/lib/cli/cli.ex
@@ -1,30 +1,70 @@
 defmodule SCLI do
   def run() do
-    str = "say: " |> IO.gets |> String.trim
+    run(nil)
+  end
+
+  defp run(pid) do
+    nick = Shard.Identity.get_nickname
+    prompt = case pid do
+      nil -> "(no channel) #{nick}: "
+      _ -> 
+        {:chat, chan} = GenServer.call(pid, :manifest)
+        "##{chan} #{nick}: "
+    end
+
+    str = prompt |> IO.gets |> String.trim
     cond do
       str == "/quit" ->
         nil
       String.slice(str, 0..0) == "/" ->
         command = str |> String.slice(1..-1) |> String.split(" ")
-        handle_command(command)
-        run()
+        pid2 = handle_command(pid, command)
+        run(pid2)
       true -> 
-        SApp.Chat.send(str)
-        run()
+        GenServer.cast(pid, {:chat_send, str})
+        run(pid)
     end
   end
 
-  def handle_command(["connect", ipstr, portstr]) do
+  def handle_command(pid, ["connect", ipstr, portstr]) do
     {:ok, ip} = :inet.parse_address (to_charlist ipstr)
     {port, _} = Integer.parse portstr
     SNet.Manager.add_peer(ip, port)
+    pid
+  end
+
+  def handle_command(pid, ["list"]) do
+    IO.puts "List of known channels:"
+    list = GenServer.call(Shard.Manager, :list)
+    for {_chid, chpid} <- list do
+      {:chat, chan} = GenServer.call(chpid, :manifest)
+      IO.puts "##{chan}"
+    end
+    pid
+  end
+
+  def handle_command(pid, ["join", qchan]) do
+    list = GenServer.call(Shard.Manager, :list)
+    list = for {_chid, chpid} <- list,
+               {:chat, chan} = GenServer.call(chpid, :manifest),
+               do: {chan, chpid}
+    case List.keyfind(list, qchan, 0) do
+      nil ->
+        {:ok, pid} = DynamicSupervisor.start_child(Shard.DynamicSupervisor, {SApp.Chat, qchan})
+        pid
+      {_, pid} ->
+        IO.puts "Switching to ##{qchan}"
+        pid
+    end
   end
 
-  def handle_command(["nick", nick]) do
+  def handle_command(pid, ["nick", nick]) do
     Shard.Identity.set_nickname nick
+    pid
   end
 
-  def handle_command(_cmd) do
+  def handle_command(pid, _cmd) do
     IO.puts "Invalid command"
+    pid
   end
 end
diff --git a/lib/data/merklelist.ex b/lib/data/merklelist.ex
index c9e27f6..42b80fc 100644
--- a/lib/data/merklelist.ex
+++ b/lib/data/merklelist.ex
@@ -1,8 +1,8 @@
 defmodule SData.MerkleList do
   use GenServer
 
-  def start_link([cmp, name: name]) do
-    GenServer.start_link(__MODULE__, cmp, [name: name])
+  def start_link(cmp) do
+    GenServer.start_link(__MODULE__, cmp)
   end
 
   defp term_hash(term) do
diff --git a/lib/manager.ex b/lib/manager.ex
new file mode 100644
index 0000000..ce11117
--- /dev/null
+++ b/lib/manager.ex
@@ -0,0 +1,46 @@
+defmodule Shard.Manager do
+  use GenServer
+
+  def start_link(_) do
+    GenServer.start_link(__MODULE__, nil, name: __MODULE__)
+  end
+
+  def init(_) do
+    state = %{
+              shards: %{}
+            }
+    {:ok, state}
+  end
+
+  def handle_call({:find, shard_id}, _from, state) do
+    {:reply, state.shards[shard_id], state}
+  end
+
+  def handle_call(:list, _from, state) do
+    {:reply, Map.to_list(state.shards), state}
+  end
+
+  def handle_cast({:register, shard_id, pid}, state) do
+    if Map.has_key?(state.shards, shard_id) do
+      GenServer.cast(pid, {:redundant, shard_id})
+      state
+    else
+      new_shards = Map.put(state.shards, shard_id, pid)
+      {:noreply, %{ state | shards: new_shards }}
+    end
+  end
+
+  def handle_cast({:interested, peer_id, peer_pid, shards}, state) do
+    shards
+    |> Enum.filter(&(Map.has_key?(state.shards, &1)))
+    |> Enum.each(&(GenServer.cast(state.shards[&1], {:interested, peer_id, peer_pid})))
+    {:noreply, state}
+  end
+
+  def handle_cast({:dispatch, peer_id, peer_pid, shard, msg}, state) do
+    if Map.has_key?(state.shards, shard) do
+      GenServer.cast(state.shards[shard], {:msg, peer_id, peer_pid, msg})
+    end
+    {:noreply, state}
+  end
+end
diff --git a/lib/net/manager.ex b/lib/net/manager.ex
index e5eb12d..4b1ce94 100644
--- a/lib/net/manager.ex
+++ b/lib/net/manager.ex
@@ -40,7 +40,12 @@ defmodule SNet.Manager do
     {:noreply, state}
   end
 
-  def handle_call({:get_connections, pk_list}, state) do
+  def handle_call(:get_all, _from, state) do
+    pid_list = (for {_, {pid, _, _}} <- state.peers, pid != nil, do: pid)
+    {:reply, pid_list, state}
+  end
+
+  def handle_call({:get_connections, pk_list}, _from, state) do
     pid_list = (for pk <- pk_list, Map.has_key?(state.peers, pk), do: state.peers[pk])
     |> Enum.map(fn {pid, _, _} -> pid end)
     |> Enum.filter(&(&1 != nil))
@@ -53,7 +58,7 @@ defmodule SNet.Manager do
 
   def add_peer(ip, port, my_port) do
     {:ok, client} = :gen_tcp.connect(ip, port, [:binary, packet: 2, active: false])
-    {:ok, pid} = DynamicSupervisor.start_child(SNet.ConnSupervisor, {SNet.TCPConn, %{socket: client, my_port: my_port}})
+    {:ok, pid} = DynamicSupervisor.start_child(Shard.DynamicSupervisor, {SNet.TCPConn, %{socket: client, my_port: my_port}})
     :ok = :gen_tcp.controlling_process(client, pid)
     pid
   end
diff --git a/lib/net/tcpconn.ex b/lib/net/tcpconn.ex
index 301e931..64c85e9 100644
--- a/lib/net/tcpconn.ex
+++ b/lib/net/tcpconn.ex
@@ -53,10 +53,9 @@ defmodule SNet.TCPConn do
         addr: addr,
         port: port
       }
-    GenServer.cast(SNet.Manager, {:peer_up, self(), cli_pkey, addr, his_port})
+    GenServer.cast(SNet.Manager, {:peer_up, cli_pkey, self(), addr, his_port})
     Logger.info "New peer: #{print_id state} at #{inspect addr}:#{port}"
-
-    GenServer.cast(self(), :init_push)
+    GenServer.cast(self(), :init_pull)
 
     {:noreply, state}
   end
@@ -66,8 +65,9 @@ defmodule SNet.TCPConn do
     {:noreply, state}
   end
 
-  def handle_cast(:init_push, state) do
-    push_messages(state, nil, 10)
+  def handle_cast(:init_pull, state) do
+    id_list = (for {id, _} <- GenServer.call(Shard.Manager, :list), do: id)
+    send_msg(state, {:interested, id_list})
     {:noreply, state}
   end
 
@@ -102,28 +102,12 @@ defmodule SNet.TCPConn do
     exit(:normal)
   end
 
-  defp push_messages(state, start, num) do
-    case GenServer.call(SApp.Chat.Log, {:read, start, num}) do
-      {:ok, list, rest} ->
-        send_msg(state, {:info, start, list, rest})
-      _ -> nil
-    end
+  defp handle_packet({:interested, shards}, state) do
+    GenServer.cast(Shard.Manager, {:interested, state.his_pkey, self(), shards})
   end
 
-  defp handle_packet(msg, state) do
-    # Logger.info "Message: #{inspect msg}"
-    case msg do
-      :get_top -> push_messages(state, nil, 10)
-      {:get, start} -> push_messages(state, start, 20)
-      {:info, _start, list, rest} ->
-        if rest != nil and not GenServer.call(SApp.Chat.Log, {:has, rest}) do
-          send_msg(state, {:get, rest})
-        end
-        spawn_link(fn ->
-          Process.sleep 1000
-          GenServer.cast(SApp.Chat.Log, {:insert_many, list, &SApp.Chat.msg_callback/1})
-        end)
-    end
+  defp handle_packet({shard, msg}, state) do
+    GenServer.cast(Shard.Manager, {:dispatch, state.his_pkey, self(), shard, msg})
   end
 
   defp print_id(state) do
diff --git a/lib/net/tcpserver.ex b/lib/net/tcpserver.ex
index 7c758c1..46552a4 100644
--- a/lib/net/tcpserver.ex
+++ b/lib/net/tcpserver.ex
@@ -18,7 +18,7 @@ defmodule SNet.TCPServer do
 
   defp loop_acceptor(socket, my_port) do
     {:ok, client} = :gen_tcp.accept(socket)
-    {:ok, pid} = DynamicSupervisor.start_child(SNet.ConnSupervisor, {SNet.TCPConn, %{socket: client, my_port: my_port}})
+    {:ok, pid} = DynamicSupervisor.start_child(Shard.DynamicSupervisor, {SNet.TCPConn, %{socket: client, my_port: my_port}})
     :ok = :gen_tcp.controlling_process(client, pid)
     loop_acceptor(socket, my_port)
   end