wip

And add the ability of other modules to listen to either
the final result (a `Key`) or tap into the input as it is read

src/input/input.gleam

@@ -0,0 +1,50 @@
+import gleam/erlang/process.{type Name, type Subject}
+
+import input/key.{type Key}
+
+/// `new` accepts a list of listeners that are composed of two subjects;
+///   - one to get the final `Key` and
+///   - one to tap the input as it is read from i/o
+/// and
+///   - a subject name that is used to create a `Subject` that other processes
+///     know they can inject a `Key` into the input with
+pub fn new(
+  ui_input_keys_name: Name(Key),
+  ui_input_stream_name: Name(List(String)),
+  input_ui_inject_name: Name(Key),
+) -> Nil {
+  let _ =
+    process.spawn(fn() {
+      let ui_input_keys: Subject(Key) =
+        process.named_subject(ui_input_keys_name)
+      let ui_input_stream: Subject(List(String)) =
+        process.named_subject(ui_input_stream_name)
+
+      let input_ui_inject_input: Subject(Key) =
+        process.named_subject(input_ui_inject_name)
+      let assert Ok(_) = process.register(process.self(), input_ui_inject_name)
+
+      read_input(ui_input_keys, ui_input_stream, input_ui_inject_input)
+    })
+
+  echo "waiting for input"
+  key.start_raw_shell()
+
+  Nil
+}
+
+fn read_input(
+  ui_input_keys: Subject(Key),
+  ui_input_stream: Subject(List(String)),
+  input_ui_inject: Subject(Key),
+) -> Nil {
+  let buffer = case process.receive(input_ui_inject, 1) {
+    Ok(key.Continue(buffer)) -> buffer
+    Ok(_) | Error(_) -> []
+  }
+
+  key.read_input_until_key(buffer, ui_input_stream)
+  |> process.send(ui_input_keys, _)
+
+  read_input(ui_input_keys, ui_input_stream, input_ui_inject)
+}

src/input/internal.gleam

@@ -10,6 +10,6 @@ pub type NotUsed
 @external(erlang, "shell", "start_interactive")
 pub fn shell_start_interactive(options: #(atom.Atom, atom.Atom)) -> NotUsed
 
-// https://www.erlang.org/doc/apps/stdlib/io.html#get_line/1
+// https://www.erlang.org/doc/apps/stdlib/io.html#get_chars/2
 @external(erlang, "io", "get_chars")
 fn io_get_chars(prompt: String, count: Int) -> String

src/input/key.gleam

@@ -0,0 +1,79 @@
+import gleam/erlang/atom
+import gleam/erlang/process.{type Subject}
+import gleam/list
+import gleam/string
+
+import input/internal as internal_input
+
+pub type Key {
+  Char(String)
+
+  Input(String)
+  Left
+  Right
+  Up
+  Down
+
+  Continue(buffer: List(String))
+  Unknown
+}
+
+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
+    [e, c, "C"] if e == esc && c == csi -> Right
+    [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(l)
+
+    [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([])
+    _ -> Unknown
+  }
+}
+
+pub fn start_raw_shell() {
+  let no_shell = atom.create("noshell")
+  let raw = atom.create("raw")
+  internal_input.shell_start_interactive(#(no_shell, raw))
+}
+
+pub fn read_input_until_key(
+  l: List(String),
+  ui_input_stream: Subject(List(String)),
+) -> Key {
+  case
+    internal_input.read_input()
+    |> list.wrap
+    |> list.append(l, _)
+    |> from_list
+  {
+    Continue(l) -> {
+      process.send(ui_input_stream, l)
+      read_input_until_key(l, ui_input_stream)
+    }
+    k -> k
+  }
+}

src/mpv/control.gleam

@@ -2,13 +2,13 @@ import gleam/json
 import gleam/result
 import gleam/string
 
-import mpv/internal/control as internal_control
-import mpv/key.{type Key, Char}
+import mpv/internal as internal_control
 import tcp/reason.{type Reason}
 import tcp/tcp.{type Socket}
 
 pub type Control {
   TogglePlayPause
+
   Exit
 }
 
@@ -16,21 +16,6 @@ pub type ControlError {
   ControlError(details: String)
 }
 
-pub fn from_key(key: Key) -> Result(Control, Nil) {
-  case key {
-    Char(char) -> char_control(char)
-    _ -> Error(Nil)
-  }
-}
-
-fn char_control(char: String) -> Result(Control, Nil) {
-  case char {
-    " " -> Ok(TogglePlayPause)
-    "q" -> Ok(Exit)
-    _ -> Error(Nil)
-  }
-}
-
 pub fn toggle_play_pause(socket: Socket) -> Result(Nil, ControlError) {
   let command =
     json.object([#("command", json.array(["cycle", "pause"], of: json.string))])

src/mpv/key.gleam

@@ -1,53 +0,0 @@
-import gleam/erlang/atom
-import gleam/list
-
-import mpv/internal/key as internal_key
-
-pub type Key {
-  Char(String)
-
-  Left
-  Right
-  Up
-  Down
-
-  Continue
-  Unknown
-}
-
-pub const esc = "\u{001B}"
-
-// control sequence introducer
-pub const csi = "["
-
-pub fn from_list(l: List(String)) -> Key {
-  case l {
-    [e, c, "D"] if e == esc && c == csi -> Left
-    [e, c, "C"] if e == esc && c == csi -> Right
-    [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] if e == esc -> Continue
-    [char] -> Char(char)
-
-    [] -> Continue
-    _ -> Unknown
-  }
-}
-
-pub fn start_raw_shell() {
-  let no_shell = atom.create("noshell")
-  let raw = atom.create("raw")
-  internal_key.shell_start_interactive(#(no_shell, raw))
-}
-
-pub fn read_input_until_key(l: List(String)) -> Key {
-  let l = internal_key.read_input() |> list.wrap |> list.append(l, _)
-
-  case from_list(l) {
-    Continue -> read_input_until_key(l)
-    k -> k
-  }
-}

src/mpv/mpv.gleam

@@ -1,36 +1,48 @@
-import gleam/erlang/process.{type Subject}
+import gleam/erlang/process.{type Name, type Subject}
 import gleam/float
 import gleam/otp/actor
 import gleam/result
 import gleam/string
 
-import mpv/control.{type Control}
-import mpv/key
+import mpv/control as mpv_control
 import tcp/reason
 import tcp/tcp.{type Socket}
+import ui/control as ui_control
 
-type State(socket, exit) {
-  State(socket: Socket, exit: Subject(Nil))
+type State(socket, mpv_ui, ui_mpv) {
+  State(
+    socket: Socket,
+    mpv_ui: Subject(ui_control.Control),
+    ui_mpv: Subject(mpv_control.Control),
+  )
 }
 
-pub fn new(exit: Subject(Nil)) -> Result(Nil, String) {
+pub fn new(
+  mpv_ui_name: Name(ui_control.Control),
+  ui_mpv_name: Name(mpv_control.Control),
+) -> Result(Nil, String) {
   // TODO start up mvp here, currently hi-jacking `naviterm`s socket
   let socket_path = "/tmp/naviterm_mpv"
 
+  let mpv_ui: Subject(ui_control.Control) = process.named_subject(mpv_ui_name)
+  let ui_mpv: Subject(mpv_control.Control) = process.named_subject(ui_mpv_name)
+
   case tcp.connect(socket_path) {
     Error(r) -> Error("Could not connect to mpv: " <> reason.to_string(r))
     Ok(socket) -> {
       case
-        actor.new(State(socket, exit))
+        actor.new(State(socket, mpv_ui, ui_mpv))
         |> actor.on_message(handle_message)
         |> actor.start
       {
         Error(start_error) ->
           Error("Could not start actor: " <> string.inspect(start_error))
-        Ok(actor.Started(data:, ..)) -> {
-          echo "waiting for input"
-          key.start_raw_shell()
-          process.spawn(fn() { read_input(data) })
+        Ok(actor.Started(data: mpv, ..)) -> {
+          process.spawn(fn() {
+            let assert Ok(_) = process.register(process.self(), ui_mpv_name)
+            handle_ui_control(mpv, ui_mpv)
+          })
+
           Ok(Nil)
         }
       }
@@ -39,40 +51,41 @@ pub fn new(exit: Subject(Nil)) -> Result(Nil, String) {
 }
 
 fn handle_message(
-  state: State(socket, exit),
-  control: Control,
-) -> actor.Next(State(socket, exit), Control) {
+  state: State(socket, mpv_ui, ui_mpv),
+  control: mpv_control.Control,
+) -> actor.Next(State(socket, mpv_ui, ui_mpv), mpv_control.Control) {
   case control {
-    control.TogglePlayPause -> {
+    mpv_control.TogglePlayPause -> {
       echo "toggling play/pause"
 
       let _ =
-        result.map_error(control.toggle_play_pause(state.socket), fn(err) {
+        result.map_error(mpv_control.toggle_play_pause(state.socket), fn(err) {
           echo "Could not toggle play/pause: " <> err.details
         })
 
       let _ =
-        result.map(control.get_playback_time(state.socket), fn(playback) {
+        result.map(mpv_control.get_playback_time(state.socket), fn(playback) {
           echo "playback: " <> float.to_string(playback.data)
         })
 
+      process.send(state.mpv_ui, ui_control.Ack)
+
       actor.continue(state)
     }
-    control.Exit -> {
-      process.send(state.exit, Nil)
+    mpv_control.Exit -> {
+      // TODO close sockets
       actor.stop()
     }
   }
 }
 
-fn read_input(subject: Subject(Control)) -> Nil {
-  case
-    key.read_input_until_key([])
-    |> control.from_key
-  {
-    Error(_) -> Nil
-    Ok(control) -> process.send(subject, control)
-  }
+fn handle_ui_control(
+  mpv: Subject(mpv_control.Control),
+  ui_mpv: Subject(mpv_control.Control),
+) {
+  let control = process.receive_forever(ui_mpv)
+  echo "handle_ui_control: " <> string.inspect(control)
+  process.send(mpv, control)
 
-  read_input(subject)
+  handle_ui_control(mpv, ui_mpv)
 }

src/musicplayer.gleam

@@ -1,8 +1,45 @@
-import gleam/erlang/process
+import gleam/erlang/process.{type Name}
+
+import input/input
+import input/key.{type Key}
+import mpv/control as mpv_control
 import mpv/mpv
+import ui/control as ui_control
+import ui/ui
 
 pub fn main() -> Nil {
   let exit = process.new_subject()
-  let assert Ok(_) = mpv.new(exit)
+
+  // `ui_input_keys` is owned by `ui`, this is where input sends keys
+  let ui_input_keys_name: Name(Key) = process.new_name("ui_input_keys")
+  // `ui_input_stream` is owned by `ui`, thi sis where input is streamed
+  let ui_input_stream_name: Name(List(String)) =
+    process.new_name("ui_input_stream")
+
+  // `inject_input` is created by name to allow the `input` process that
+  // owns `read_input` to be able to register and receive from it,
+  //  while the any other processes can use the name reference to
+  // inject input
+
+  // `input_ui_inject`  is owned by `input`, this is where `ui` injects `Key`
+  let input_ui_inject_name: Name(Key) = process.new_name("input_ui_inject_keys")
+
+  // `ui_mpv` is owned by `ui`, this is where `ui` asks `mpv` for things
+  let ui_mpv_name: Name(mpv_control.Control) = process.new_name("ui_mpv")
+  //   `mpv_ui` is owned by mpv and this is where mpv responds to ui
+  let mpv_ui_name: Name(ui_control.Control) = process.new_name("mpv_ui")
+
+  let assert Ok(_) =
+    ui.new(
+      ui_mpv_name,
+      mpv_ui_name,
+      ui_input_keys_name,
+      ui_input_stream_name,
+      exit,
+    )
+
+  let assert Ok(_) = mpv.new(mpv_ui_name, ui_mpv_name)
+  input.new(ui_input_keys_name, ui_input_stream_name, input_ui_inject_name)
+
   process.receive_forever(exit)
 }

src/ui/control.gleam

@@ -0,0 +1,24 @@
+import input/key.{type Key}
+
+pub type Control {
+  Ack
+
+  TogglePlayPause
+
+  Exit
+}
+
+pub fn from_key(key: Key) -> Result(Control, Nil) {
+  case key {
+    key.Char(char) -> char_control(char)
+    _ -> Error(Nil)
+  }
+}
+
+fn char_control(char: String) -> Result(Control, Nil) {
+  case char {
+    " " -> Ok(TogglePlayPause)
+    "q" -> Ok(Exit)
+    _ -> Error(Nil)
+  }
+}

src/ui/ui.gleam

@@ -0,0 +1,122 @@
+import gleam/erlang/process.{type Name, type Subject}
+import gleam/otp/actor
+import gleam/result
+import gleam/string
+
+import input/key.{type Key}
+import mpv/control as mpv_control
+import ui/control as ui_control
+
+pub type State(ui_mpv, mpv_ui, ui_input_keys, ui_input_stream, exit) {
+  State(
+    ui_mpv: Subject(mpv_control.Control),
+    mpv_ui: Subject(ui_control.Control),
+    ui_input_keys: Subject(Key),
+    ui_input_stream: Subject(List(String)),
+    exit: Subject(Nil),
+  )
+}
+
+pub fn new(
+  ui_mpv_name: Name(mpv_control.Control),
+  mpv_ui_name: Name(ui_control.Control),
+  ui_input_keys_name: Name(Key),
+  ui_input_stream_name: Name(List(String)),
+  exit: Subject(Nil),
+) -> Result(Nil, String) {
+  let ui_mpv: Subject(mpv_control.Control) = process.named_subject(ui_mpv_name)
+  let mpv_ui: Subject(ui_control.Control) = process.named_subject(mpv_ui_name)
+
+  let ui_input_keys: Subject(Key) = process.named_subject(ui_input_keys_name)
+  let ui_input_stream: Subject(List(String)) =
+    process.named_subject(ui_input_stream_name)
+
+  case
+    actor.new(State(ui_mpv, mpv_ui, ui_input_keys, ui_input_stream, exit))
+    |> actor.on_message(handle_message)
+    |> actor.start
+  {
+    Error(start_error) ->
+      Error("Could not start ui: " <> string.inspect(start_error))
+    Ok(actor.Started(data: ui, ..)) -> {
+      echo "ui started"
+
+      process.spawn(fn() {
+        let assert Ok(_) = process.register(process.self(), ui_input_keys_name)
+        handle_key(ui, ui_input_keys)
+      })
+
+      process.spawn(fn() {
+        let assert Ok(_) = process.register(process.self(), mpv_ui_name)
+        handle_mpv_control(ui, mpv_ui)
+      })
+
+      process.spawn(fn() {
+        let assert Ok(_) =
+          process.register(process.self(), ui_input_stream_name)
+        temp_input_stream(ui_input_stream)
+      })
+
+      Ok(Nil)
+    }
+  }
+}
+
+fn handle_message(
+  state: State(ui_mpv, mpv_ui, ui_input_keys, ui_input_stream, exit),
+  control: ui_control.Control,
+) -> actor.Next(
+  State(ui_mpv, mpv_ui, ui_input_keys, ui_input_stream, exit),
+  ui_control.Control,
+) {
+  case control {
+    ui_control.Ack -> {
+      echo "ack! use this to re-render?"
+      actor.continue(state)
+    }
+    ui_control.TogglePlayPause -> {
+      process.send(state.mpv_ui, ui_control.TogglePlayPause)
+      case process.receive(state.mpv_ui, 5000) {
+        Error(_) -> echo "mpv not responding: could not toggle pause :("
+        Ok(_) -> echo "toggled pause"
+      }
+
+      actor.continue(state)
+    }
+    ui_control.Exit -> {
+      // TODO call `mpv` to exit, wait for response
+      process.send(state.exit, Nil)
+      actor.stop()
+    }
+  }
+}
+
+/// `handle_key` listens to a subject onto which `input` will send messages with
+/// parsed `Key`s which will be mapped to `Control`s (if possible)
+fn handle_key(
+  ui: Subject(ui_control.Control),
+  ui_input_keys: Subject(Key),
+) -> Nil {
+  let _ =
+    process.receive_forever(ui_input_keys)
+    |> ui_control.from_key
+    |> result.map(process.send(ui, _))
+
+  handle_key(ui, ui_input_keys)
+}
+
+fn handle_mpv_control(
+  ui: Subject(ui_control.Control),
+  mpv_ui: Subject(ui_control.Control),
+) {
+  let control = process.receive_forever(mpv_ui)
+  process.send(ui, control)
+
+  handle_mpv_control(ui, mpv_ui)
+}
+
+fn temp_input_stream(ui_input_stream: Subject(List(String))) -> Nil {
+  let stream = process.receive_forever(ui_input_stream)
+  echo "input stream: " <> string.inspect(stream)
+  temp_input_stream(ui_input_stream)
+}

test/input/input_test.gleam

@@ -0,0 +1,42 @@
+import gleam/list
+import gleeunit
+
+import input/key.{type Key, Char, csi, esc, input_introducer as ii}
+
+pub fn main() -> Nil {
+  gleeunit.main()
+}
+
+type TestCase {
+  TestCase(input: List(String), expected: Key)
+}
+
+pub fn key_from_list_test() {
+  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),
+  ]
+
+  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", "\u{007F}"], key.Continue([ii, "a"])),
+    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)
+  })
+}

test/mpv/control_test.gleam

@@ -1,29 +1,11 @@
-import gleam/list
 import gleeunit
 
-import mpv/control.{type Control}
-import mpv/internal/control as control_internal
-import mpv/key.{type Key, Char}
+import mpv/internal as control_internal
 
 pub fn main() -> Nil {
   gleeunit.main()
 }
 
-type TestCase {
-  TestCase(key: Key, expected: Result(Control, Nil))
-}
-
-pub fn control_from_key_test() {
-  let test_cases = [
-    TestCase(Char(" "), Ok(control.TogglePlayPause)),
-    TestCase(Char("q"), Ok(control.Exit)),
-  ]
-
-  list.each(test_cases, fn(tc) {
-    assert tc.expected == control.from_key(tc.key)
-  })
-}
-
 pub fn parse_playback_time_test() {
   let json_string =
     "{\"data\":\"123.456789\",\"request_id\":0,\"error\":\"success\"}\n"

test/mpv/key_test.gleam

@@ -1,29 +0,0 @@
-import gleam/list
-import gleeunit
-
-import mpv/key.{type Key, Char, csi, esc}
-
-pub fn main() -> Nil {
-  gleeunit.main()
-}
-
-type TestCase {
-  TestCase(input: List(String), expected: Key)
-}
-
-pub fn key_from_list_test() {
-  let test_cases = [
-    TestCase(["c"], Char("c")),
-    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) {
-    assert tc.expected == key.from_list(tc.input)
-  })
-}

test/ui/ui_test.gleam

@@ -0,0 +1,24 @@
+import gleam/list
+import gleeunit
+
+import input/key.{type Key, Char}
+import ui/control.{type Control}
+
+pub fn main() -> Nil {
+  gleeunit.main()
+}
+
+type TestCase {
+  TestCase(key: Key, expected: Result(Control, Nil))
+}
+
+pub fn control_from_key_test() {
+  let test_cases = [
+    TestCase(Char(" "), Ok(control.TogglePlayPause)),
+    TestCase(Char("q"), Ok(control.Exit)),
+  ]
+
+  list.each(test_cases, fn(tc) {
+    assert tc.expected == control.from_key(tc.key)
+  })
+}