wip

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)
+}