Add configuration module

lib/ex_webrtc/peer_connection.ex

@@ -3,28 +3,26 @@ defmodule ExWebRTC.PeerConnection do
 
   use GenServer
 
+  alias __MODULE__.Configuration
   alias ExWebRTC.SessionDescription
 
   @type peer_connection() :: GenServer.server()
 
-  @type bundle_policy() ::
-    :balanced
-    | :max_compat
-    | :max_bundle
-
-  @type configuration() :: [
-    bundle_policy: bundle_policy(),
-    certificates: term(),
-    ice_candidate_pool_size: term(),
-    ice_servers: term(),
-    ice_transport_policy: term(),
-    peer_identity: term(),
-    rtcp_mux_policy: term()
-  ]
-
   @type offer_options() :: [ice_restart: boolean()]
   @type answer_options() :: []
 
+  @enforce_keys [:config]
+  defstruct @enforce_keys ++
+              [
+                :current_local_desc,
+                :pending_local_desc,
+                :current_remote_desc,
+                :pending_remote_desc,
+                :ice_agent,
+                transceivers: [],
+                signaling_state: :stable
+              ]
+
   #### API ####
 
   def start_link(configuration \\ []) do
@@ -35,22 +33,26 @@ defmodule ExWebRTC.PeerConnection do
     GenServer.start(__MODULE__, configuration)
   end
 
-  @spec create_offer(peer_connection(), offer_options()) :: {:ok, SessionDescription.t()} | {:error, :TODO}  # TODO reason
+  @spec create_offer(peer_connection(), offer_options()) ::
+          {:ok, SessionDescription.t()} | {:error, :TODO}
   def create_offer(peer_connection, options \\ []) do
     GenServer.call(peer_connection, {:create_offer, options})
   end
 
-  @spec create_answer(peer_connection(), answer_options()) :: {:ok, SessionDescription.t()} | {:error, :TODO}  # TODO reasons
+  @spec create_answer(peer_connection(), answer_options()) ::
+          {:ok, SessionDescription.t()} | {:error, :TODO}
   def create_answer(peer_connection, options \\ []) do
     GenServer.call(peer_connection, {:create_answer, options})
   end
 
-  @spec set_local_description(peer_connection(), SessionDescription.t()) :: :ok | {:error, :TODO}  # TODO resons
+  @spec set_local_description(peer_connection(), SessionDescription.t()) ::
+          :ok | {:error, :TODO}
   def set_local_description(peer_connection, description) do
     GenServer.call(peer_connection, {:set_local_description, description})
   end
 
-  @spec set_remote_description(peer_connection(), SessionDescription.t()) :: :ok | {:error, :TODO}  # TODO resons
+  @spec set_remote_description(peer_connection(), SessionDescription.t()) ::
+          :ok | {:error, :TODO}
   def set_remote_description(peer_connection, description) do
     GenServer.call(peer_connection, {:set_remote_description, description})
   end
@@ -59,41 +61,49 @@ defmodule ExWebRTC.PeerConnection do
 
   @impl true
   def init(config) do
-    _bundle_policy = Keyword.get(config, :bundle_policy, :balanced)
-    {:ok, %{}}
+    config = struct(Configuration, config)
+    :ok = Configuration.check_support(config)
+
+    state = %__MODULE__{config: config}
+
+    {:ok, state}
   end
 
   @impl true
   def handle_call({:create_offer, options}, _from, state) do
     _ice_restart = Keyword.get(options, :ice_restart, false)
 
-    sdp = 
+    # TODO probably will need to move SDP stuff to its module
+    sdp =
       %{ExSDP.new() | timing: %ExSDP.Timing{start_time: 0, stop_time: 0}}
       |> ExSDP.add_attribute({:ice_options, "trickle"})
 
-    # identity?
-
-    # for each RTPTransceiver add "m=" section
+    sdp = Enum.reduce(state.transceivers, sdp, &add_media_description/2)
 
     desc = %SessionDescription{type: :offer, sdp: to_string(sdp)}
     {:reply, {:ok, desc}, state}
   end
 
   @impl true
   def handle_call({:create_answer, _options}, _from, state) do
-    sdp = ExSDP.new()
-
-    desc = %SessionDescription{type: :answer, sdp: to_string(sdp)}
-    {:reply, {:ok, desc}, state}
+    # TODO
+    {:reply, :ok, state}
   end
 
   @impl true
   def handle_call({:set_local_description, _desc}, _from, state) do
+    # TODO
     {:reply, :ok, state}
   end
 
   @impl true
   def handle_call({:set_remote_description, _desc}, _from, state) do
+    # TODO
     {:reply, :ok, state}
   end
+
+  defp add_media_description(_transceiver, sdp) do
+    # TODO
+    sdp
+  end
 end

lib/ex_webrtc/peer_connection/configuration.ex

@@ -0,0 +1,64 @@
+defmodule ExWebRTC.PeerConnection.Configuration do
+  @moduledoc false
+
+  @type bundle_policy() ::
+          :balanced
+          | :max_compat
+          | :max_bundle
+
+  @type ice_transport_policy() ::
+          :all
+          | :relay
+
+  @type rtcp_mux_policy() ::
+          :negotiate
+          | :require
+
+  @type t() :: %__MODULE__{
+          bundle_policy: bundle_policy(),
+          # TODO certs type
+          certificates: term(),
+          ice_candidate_pool_size: non_neg_integer(),
+          ice_servers: [String.t()],
+          ice_transport_policy: ice_transport_policy(),
+          peer_identity: String.t(),
+          rtcp_mux_policy: rtcp_mux_policy()
+        }
+
+  defstruct bundle_policy: :balanced,
+            certificates: nil,
+            ice_candidate_pool_size: 0,
+            ice_servers: [],
+            ice_transport_policy: :all,
+            peer_identity: nil,
+            rtcp_mux_policy: :require
+
+  @spec check_support(t()) :: :ok
+  def check_support(config) do
+    if config.ice_transport_policy != :all do
+      raise "#{inspect(config.ice_transport_policy)} ice transport policy is currently not supported"
+    end
+
+    if config.ice_candidate_pool_size != 0 do
+      raise "Ice candidate pool size different than 0 (pre-gathering) is currently not supported"
+    end
+
+    if config.bundle_policy != :max_bundle do
+      raise "Bundle policy options different than :max_bundle are currently not supported"
+    end
+
+    if config.certificates != nil do
+      raise "Certificates configuration option is currently not supported"
+    end
+
+    if config.peer_identity != nil do
+      raise "Identify option is currently not supported"
+    end
+
+    if config.rtcp_mux_policy != :require do
+      raise "RTCP mux policy option :negotiate is currently not supported"
+    end
+
+    :ok
+  end
+end

lib/ex_webrtc/peer_connection/signaling_state.ex

@@ -0,0 +1,10 @@
+defmodule ExWebRTC.PeerConnection.SignalingState do
+  @moduledoc false
+
+  @type t() ::
+          :stable
+          | :have_local_offer
+          | :have_remote_offer
+          | :have_local_pranswer
+          | :have_remote_pranswer
+end

lib/ex_webrtc/peer_connection/transceiver.ex

@@ -0,0 +1,31 @@
+defmodule ExWebRTC.PeerConnection.Transceiver do
+  @moduledoc false
+
+  @type kind() ::
+          :audio
+          | :video
+
+  @type direction() ::
+          :sendrecv
+          | :sendonly
+          | :recvonly
+          | :inactive
+          | :stopped
+
+  @type options() :: [
+          direction
+        ]
+
+  # @type t() :: %__MODULE__{
+  #   mid: String.t() | nil,
+  #   current_direction: direction() | nil,
+  #   direction: direction(),
+  #   receiver: term(),
+  #   sender: term(),
+  #   send_encodings: term(),
+  #   streams: term()
+  # }
+  #
+  # @enforce_keys [:direction]
+  # defstruct @enforce_keys ++ [:mid, :current_direction]
+end

lib/ex_webrtc/session_description.ex

@@ -2,15 +2,15 @@ defmodule ExWebRTC.SessionDescription do
   @moduledoc false
 
   @type description_type() ::
-    :answer
-    | :offer
-    | :pranswer
-    | :rollback
+          :answer
+          | :offer
+          | :pranswer
+          | :rollback
 
   @type t() :: %__MODULE__{
-    type: description_type(),
-    sdp: String.t()
-  }
+          type: description_type(),
+          sdp: String.t()
+        }
 
   @enforce_keys [:type, :sdp]
   defstruct @enforce_keys