From 4d935a2e29fc756536384c1586a930bce20f93de Mon Sep 17 00:00:00 2001
From: Alexander Heldt <me@alexanderheldt.se>
Date: Sun, 16 Nov 2025 20:37:34 +0100
Subject: [PATCH] Add ability to create character sequences as `Input`

---
 src/input/key.gleam         | 35 +++++++++++++++++++++++++++--------
 src/mpv/control.gleam       |  5 +++--
 test/input/input_test.gleam | 26 +++++++++++++++++++-------
 3 files changed, 49 insertions(+), 17 deletions(-)

diff --git a/src/input/key.gleam b/src/input/key.gleam
index 12fd6cb..ffc92c6 100644
--- a/src/input/key.gleam
+++ b/src/input/key.gleam
@@ -1,17 +1,19 @@
 import gleam/erlang/atom
 import gleam/list
+import gleam/string
 
 import input/internal as internal_input
 
 pub type Key {
   Char(String)
 
+  Input(String)
   Left
   Right
   Up
   Down
 
-  Continue
+  Continue(buffer: List(String))
   Unknown
 }
 
@@ -20,6 +22,9 @@ pub const esc = "\u{001B}"
 // control sequence introducer
 pub const csi = "["
 
+// input introducer
+pub const input_introducer = "::"
+
 pub fn from_list(l: List(String)) -> Key {
   case l {
     [e, c, "D"] if e == esc && c == csi -> Left
@@ -27,12 +32,23 @@ pub fn from_list(l: List(String)) -> Key {
     [e, c, "A"] if e == esc && c == csi -> Up
     [e, c, "B"] if e == esc && c == csi -> Down
 
-    [e, c] if e == esc && c == csi -> Continue
+    [e, c] if e == esc && c == csi -> Continue(l)
 
-    [e] if e == esc -> Continue
+    [ci] | [ci, _] if ci == input_introducer -> Continue(l)
+    [ii, cmd, tail] if ii == input_introducer -> {
+      case tail {
+        // Return
+        "\r" -> Input(cmd)
+        // Backspace
+        "\u{007F}" -> Continue([ii, string.drop_end(cmd, 1)])
+        _ -> Continue([ii, cmd <> tail])
+      }
+    }
+
+    [e] if e == esc -> Continue(l)
     [char] -> Char(char)
 
-    [] -> Continue
+    [] -> Continue([])
     _ -> Unknown
   }
 }
@@ -44,10 +60,13 @@ pub fn start_raw_shell() {
 }
 
 pub fn read_input_until_key(l: List(String)) -> Key {
-  let l = internal_input.read_input() |> list.wrap |> list.append(l, _)
-
-  case from_list(l) {
-    Continue -> read_input_until_key(l)
+  case
+    internal_input.read_input()
+    |> list.wrap
+    |> list.append(l, _)
+    |> from_list
+  {
+    Continue(l) -> read_input_until_key(l)
     k -> k
   }
 }
diff --git a/src/mpv/control.gleam b/src/mpv/control.gleam
index 7f63d9d..690beaf 100644
--- a/src/mpv/control.gleam
+++ b/src/mpv/control.gleam
@@ -2,13 +2,14 @@ import gleam/json
 import gleam/result
 import gleam/string
 
-import input/key.{type Key, Char}
+import input/key.{type Key}
 import mpv/internal/control as internal_control
 import tcp/reason.{type Reason}
 import tcp/tcp.{type Socket}
 
 pub type Control {
   TogglePlayPause
+
   Exit
 }
 
@@ -18,7 +19,7 @@ pub type ControlError {
 
 pub fn from_key(key: Key) -> Result(Control, Nil) {
   case key {
-    Char(char) -> char_control(char)
+    key.Char(char) -> char_control(char)
     _ -> Error(Nil)
   }
 }
diff --git a/test/input/input_test.gleam b/test/input/input_test.gleam
index 3777af5..2863aa1 100644
--- a/test/input/input_test.gleam
+++ b/test/input/input_test.gleam
@@ -1,7 +1,7 @@
 import gleam/list
 import gleeunit
 
-import input/key.{type Key, Char, csi, esc}
+import input/key.{type Key, Char, csi, esc, input_introducer as ii}
 
 pub fn main() -> Nil {
   gleeunit.main()
@@ -12,18 +12,30 @@ type TestCase {
 }
 
 pub fn key_from_list_test() {
-  let test_cases = [
-    TestCase(["c"], Char("c")),
+  let base_tests = [TestCase([], key.Continue([]))]
+
+  let char_tests = [TestCase(["c"], Char("c"))]
+
+  let escape_tests = [
+    TestCase([esc, csi], key.Continue([esc, csi])),
+    TestCase([esc], key.Continue([esc])),
+
     TestCase([esc, csi, "D"], key.Left),
     TestCase([esc, csi, "C"], key.Right),
     TestCase([esc, csi, "A"], key.Up),
     TestCase([esc, csi, "B"], key.Down),
-    TestCase([esc, csi], key.Continue),
-    TestCase([esc], key.Continue),
-    TestCase([], key.Continue),
   ]
 
-  list.each(test_cases, fn(tc) {
+  let input_tests = [
+    TestCase([ii], key.Continue([ii])),
+    TestCase([ii, "a"], key.Continue([ii, "a"])),
+    TestCase([ii, "a", "b"], key.Continue([ii, "ab"])),
+    TestCase([ii, "ab", "\r"], key.Input("ab")),
+  ]
+
+  let test_cases = [base_tests, char_tests, escape_tests, input_tests]
+
+  list.each(list.flatten(test_cases), fn(tc) {
     assert tc.expected == key.from_list(tc.input)
   })
 }