From f08ab265647f085b4f9126fd728431beb7f43092 Mon Sep 17 00:00:00 2001
From: Marcin Kulik <m@ku1ik.com>
Date: Thu, 17 Oct 2024 11:17:58 +0200
Subject: [PATCH] Use more compact RGB color notation for snapshots

---
 lib/asciinema/recordings/snapshot.ex        | 16 +++++++++++++---
 native/vt_nif/src/lib.rs                    |  4 ++--
 test/asciinema/recordings/snapshot_test.exs | 17 ++++++++++++++---
 test/asciinema/vt_test.exs                  |  7 ++++---
 4 files changed, 33 insertions(+), 11 deletions(-)

diff --git a/lib/asciinema/recordings/snapshot.ex b/lib/asciinema/recordings/snapshot.ex
index 6b1ca6ea6..ec0edc6ad 100644
--- a/lib/asciinema/recordings/snapshot.ex
+++ b/lib/asciinema/recordings/snapshot.ex
@@ -180,11 +180,13 @@ defmodule Asciinema.Recordings.Snapshot do
       case {k, v} do
         {"fg", c} when is_number(c) and c < 8 -> "3#{c}"
         {"fg", c} when is_number(c) -> "38;5;#{c}"
-        {"fg", "rgb(" <> _} -> "38;2;#{parse_rgb(v)}"
+        {"fg", "#" <> _} -> "38;2;#{parse_hex_color(v)}"
+        {"fg", "rgb(" <> _} -> "38;2;#{parse_rgb_color(v)}"
         {"fg", [r, g, b]} -> "38;2;#{r};#{g};#{b}"
         {"bg", c} when is_number(c) and c < 8 -> "4#{c}"
         {"bg", c} when is_number(c) -> "48;5;#{c}"
-        {"bg", "rgb(" <> _} -> "48;2;#{parse_rgb(v)}"
+        {"bg", "#" <> _} -> "48;2;#{parse_hex_color(v)}"
+        {"bg", "rgb(" <> _} -> "48;2;#{parse_rgb_color(v)}"
         {"bg", [r, g, b]} -> "48;2;#{r};#{g};#{b}"
         {"bold", true} -> "1"
         {"faint", true} -> "2"
@@ -200,7 +202,15 @@ defmodule Asciinema.Recordings.Snapshot do
 
   defp sgr_params([]), do: []
 
-  defp parse_rgb("rgb(" <> c) do
+  defp parse_hex_color(<<"#", r::binary-size(2), g::binary-size(2), b::binary-size(2)>>) do
+    r = String.to_integer(r, 16)
+    g = String.to_integer(g, 16)
+    b = String.to_integer(b, 16)
+
+    "#{r};#{g};#{b}"
+  end
+
+  defp parse_rgb_color("rgb(" <> c) do
     c
     |> String.slice(0, String.length(c) - 1)
     |> String.split(",")
diff --git a/native/vt_nif/src/lib.rs b/native/vt_nif/src/lib.rs
index f80e3f86e..1e7242c39 100644
--- a/native/vt_nif/src/lib.rs
+++ b/native/vt_nif/src/lib.rs
@@ -129,7 +129,7 @@ fn chunk_to_term(cells: Vec<avt::Cell>, env: Env) -> Term {
         }
 
         Some(avt::Color::RGB(c)) => {
-            let c = format!("rgb({},{},{})", c.r, c.g, c.b);
+            let c = format!("#{:02x}{:02x}{:02x}", c.r, c.g, c.b);
             pairs.push(("fg".to_owned(), c.encode(env)));
         }
 
@@ -142,7 +142,7 @@ fn chunk_to_term(cells: Vec<avt::Cell>, env: Env) -> Term {
         }
 
         Some(avt::Color::RGB(c)) => {
-            let c = format!("rgb({},{},{})", c.r, c.g, c.b);
+            let c = format!("#{:02x}{:02x}{:02x}", c.r, c.g, c.b);
             pairs.push(("bg".to_owned(), c.encode(env)));
         }
 
diff --git a/test/asciinema/recordings/snapshot_test.exs b/test/asciinema/recordings/snapshot_test.exs
index 0e2e17d62..4555d9f25 100644
--- a/test/asciinema/recordings/snapshot_test.exs
+++ b/test/asciinema/recordings/snapshot_test.exs
@@ -180,7 +180,7 @@ defmodule Asciinema.Recordings.SnapshotTest do
 
   @lines [
     [[" foo bar  baz", %{"bg" => 2}, 1], ["!", %{"fg" => 1}, 1]],
-    [["qux", %{"bg" => 2}, 1], ["连", %{}, 2], ["接", %{}, 2]]
+    [["qux", %{"bg" => "#102030"}, 1], ["连", %{}, 2], ["接", %{}, 2]]
   ]
 
   describe "fg_coords/1" do
@@ -202,7 +202,7 @@ defmodule Asciinema.Recordings.SnapshotTest do
                %{
                  y: 1,
                  segments: [
-                   %{text: "qux", attrs: %{"bg" => 2}, x: 0, width: 3},
+                   %{text: "qux", attrs: %{"bg" => "#102030"}, x: 0, width: 3},
                    %{text: "连", attrs: %{}, x: 3, width: 2},
                    %{text: "接", attrs: %{}, x: 5, width: 2}
                  ]
@@ -228,10 +228,21 @@ defmodule Asciinema.Recordings.SnapshotTest do
                %{
                  y: 1,
                  segments: [
-                   %{attrs: %{"bg" => 2}, x: 0, width: 3}
+                   %{attrs: %{"bg" => "#102030"}, x: 0, width: 3}
                  ]
                }
              ]
     end
   end
+
+  describe "seq/1" do
+    test "dumps snapshot as an ANSI sequence" do
+      seq =
+        @lines
+        |> Snapshot.new()
+        |> Snapshot.seq()
+
+      assert seq == "\e[42m foo bar  baz\e[0m\e[31m!\e[0m\r\n\e[48;2;16;32;48mqux\e[0m连接\e[?25l"
+    end
+  end
 end
diff --git a/test/asciinema/vt_test.exs b/test/asciinema/vt_test.exs
index 1352eb6b5..518171d55 100644
--- a/test/asciinema/vt_test.exs
+++ b/test/asciinema/vt_test.exs
@@ -10,7 +10,8 @@ defmodule Asciinema.VtTest do
         Vt.with_vt(8, 3, fn vt ->
           Vt.feed(vt, "foobar\r\n")
           Vt.feed(vt, "baz")
-          Vt.feed(vt, "全")
+          Vt.feed(vt, "全\r\n")
+          Vt.feed(vt, "\x1b[1;38:2:16:32:48mqux")
           Vt.dump_screen(vt)
         end)
 
@@ -18,8 +19,8 @@ defmodule Asciinema.VtTest do
               {[
                  [{"foobar  ", %{}, 1}],
                  [{"baz", %{}, 1}, {"全", %{}, 2}, {"    ", %{}, 1}],
-                 [{"        ", %{}, 1}]
-               ], {4, 1}}} = result
+                 [{"qux", %{"bold" => true, "fg" => "#102030"}, 1}, {"     ", %{}, 1}]
+               ], {3, 2}}} = result
     end
 
     test "feeding it a lot of data" do