Refactor live stream theme parsing

Author: ku1ik

lib/asciinema/colors.ex

@@ -10,9 +10,10 @@ defmodule Asciinema.Colors do
   end
 
   def hex(r, g, b), do: "##{hex(r)}#{hex(g)}#{hex(b)}"
+  def hex({r, g, b}), do: hex(r, g, b)
   def hex([r, g, b]), do: hex(r, g, b)
 
-  def hex(int) do
+  def hex(int) when is_integer(int) do
     int
     |> Integer.to_string(16)
     |> String.pad_leading(2, "0")

lib/asciinema/streaming/live_stream_server.ex

@@ -2,7 +2,7 @@ defmodule Asciinema.Streaming.LiveStreamServer do
   use GenServer, restart: :temporary
   alias Asciinema.Recordings.Snapshot
   alias Asciinema.Streaming.ViewerTracker
-  alias Asciinema.{PubSub, Streaming, Vt}
+  alias Asciinema.{Colors, PubSub, Streaming, Vt}
   require Logger
 
   defmodule Update do
@@ -296,10 +296,15 @@ defmodule Asciinema.Streaming.LiveStreamServer do
   defp theme_fields(nil), do: [theme_fg: nil, theme_bg: nil, theme_palette: nil]
 
   defp theme_fields(theme) do
+    palette =
+      theme.palette
+      |> Enum.map(&Colors.hex/1)
+      |> Enum.join(":")
+
     [
-      theme_fg: theme.fg,
-      theme_bg: theme.bg,
-      theme_palette: Enum.join(theme.palette, ":")
+      theme_fg: Colors.hex(theme.fg),
+      theme_bg: Colors.hex(theme.bg),
+      theme_palette: palette
     ]
   end
 

lib/asciinema/streaming/parser/alis.ex

@@ -1,11 +1,6 @@
 defmodule Asciinema.Streaming.Parser.Alis do
-  alias Asciinema.Colors
-
   @behaviour Asciinema.Streaming.Parser
 
-  @theme_absent 0x00
-  @theme_present 0x01
-
   def init, do: %{status: :new}
 
   def parse({:binary, "ALiS\x01"}, %{status: :new} = state) do
@@ -24,38 +19,36 @@ defmodule Asciinema.Streaming.Parser.Alis do
             cols::little-16,
             rows::little-16,
             time::little-float-32,
-            @theme_absent::8,
-            init_len::little-32,
-            init::binary-size(init_len)
+            palette_len::8,
+            rest::binary
           >>
         },
         %{status: status} = state
       )
       when status in [:init, :offline] do
-    {:ok, [reset: %{size: {cols, rows}, init: init, time: time}], %{state | status: :online}}
-  end
+    palette_len =
+      case palette_len do
+        0 -> 0
+        # TODO: legacy, used by RC CLIs, remove after release of final CLI 3.0
+        1 -> 16
+        8 -> 8
+        16 -> 16
+      end
 
-  def parse(
-        {
-          :binary,
-          <<
-            0x01,
-            cols::little-16,
-            rows::little-16,
-            time::little-float-32,
-            @theme_present::8,
-            theme::binary-size(18 * 3),
-            init_len::little-32,
-            init::binary-size(init_len)
-          >>
-        },
-        %{status: status} = state
-      )
-      when status in [:init, :offline] do
+    theme_len = (2 + palette_len) * 3
+    <<theme::binary-size(theme_len), init_len::little-32, init::binary-size(init_len)>> = rest
     theme = parse_theme(theme)
 
-    {:ok, [reset: %{size: {cols, rows}, init: init, time: time, theme: theme}],
-     %{state | status: :online}}
+    commands = [
+      reset: %{
+        size: {cols, rows},
+        init: init,
+        time: time,
+        theme: theme
+      }
+    ]
+
+    {:ok, commands, %{state | status: :online}}
   end
 
   def parse(
@@ -97,7 +90,7 @@ defmodule Asciinema.Streaming.Parser.Alis do
   end
 
   defp parse_theme(theme) do
-    colors = for <<r::8, g::8, b::8 <- theme>>, do: Colors.hex(r, g, b)
+    colors = for <<r::8, g::8, b::8 <- theme>>, do: {r, g, b}
 
     %{
       fg: Enum.at(colors, 0),

lib/asciinema/streaming/parser/json.ex

@@ -1,4 +1,6 @@
 defmodule Asciinema.Streaming.Parser.Json do
+  alias Asciinema.Colors
+
   @behaviour Asciinema.Streaming.Parser
 
   def init, do: %{first: true}
@@ -69,10 +71,17 @@ defmodule Asciinema.Streaming.Parser.Json do
   defp parse_theme(nil), do: nil
 
   defp parse_theme(%{"fg" => fg, "bg" => bg, "palette" => palette}) do
+    palette =
+      palette
+      |> String.split(":")
+      |> Enum.map(&Colors.parse/1)
+
+    true = length(palette) == 8 or length(palette) == 16
+
     %{
-      fg: fg,
-      bg: bg,
-      palette: String.split(palette, ":")
+      fg: Colors.parse(fg),
+      bg: Colors.parse(bg),
+      palette: palette
     }
   end
 end

lib/asciinema_web/live_stream_consumer_socket.ex

@@ -1,5 +1,5 @@
 defmodule AsciinemaWeb.LiveStreamConsumerSocket do
-  alias Asciinema.{Accounts, Authorization, Colors, Streaming}
+  alias Asciinema.{Accounts, Authorization, Streaming}
   alias Asciinema.Streaming.{LiveStreamServer, ViewerTracker}
   alias AsciinemaWeb.Endpoint
   require Logger
@@ -184,7 +184,7 @@ defmodule AsciinemaWeb.LiveStreamConsumerSocket do
       rows::little-16,
       time::little-float-32,
       theme_presence::8,
-      theme::binary-size(18 * 3),
+      theme::binary,
       init_len::little-32,
       init::binary
     >>
@@ -224,9 +224,7 @@ defmodule AsciinemaWeb.LiveStreamConsumerSocket do
   end
 
   defp encode_theme(%{fg: fg, bg: bg, palette: palette}) do
-    for color <- [fg, bg | palette], into: <<>> do
-      {r, g, b} = Colors.parse(color)
-
+    for {r, g, b} <- [fg, bg | palette], into: <<>> do
       <<r::8, g::8, b::8>>
     end
   end