Use StringTree to store the rendered layout

And print the entire layout at once

src/musicplayer.gleam

@@ -8,15 +8,14 @@ import musicplayer/musicplayer
 import musicplayer/ui/ui
 
 pub fn main() -> Nil {
-  let assert Ok(logger) = logging.new("/tmp/musicplayer.log")
+  let assert Ok(_) = logging.initialize()
 
   let input_keys_name: Name(Key) = process.new_name("input_keys")
   input.new(input_keys_name)
 
   let assert Ok(ui) = ui.new()
   let assert Ok(mpv) = mpv.new()
-  let assert Ok(musicplayer_pid) =
+  let assert Ok(musicplayer_pid) = musicplayer.new(ui, mpv, input_keys_name)
-    musicplayer.new(logger, ui, mpv, input_keys_name)
 
   let monitor = process.monitor(musicplayer_pid)
   process.new_selector()

src/musicplayer/logging/control.gleam

@@ -1,7 +1,5 @@
-import gleam/erlang/process.{type Subject}
-
 pub type Control {
   Write(String)
 
-  Exit(reply_to: Subject(Nil))
+  Exit
 }

src/musicplayer/logging/logging.gleam

@@ -1,40 +1,22 @@
-import gleam/erlang/process.{type Subject}
-import gleam/otp/actor
 import gleam/result
 import gleam/string
 import gleam/time/calendar
 import gleam/time/timestamp
 import simplifile
 
-import musicplayer/logging/control.{type Control}
+const filepath = "/tmp/musicplayer.log"
 
-type State {
+pub fn initialize() -> Result(Nil, String) {
-  State(filepath: String)
-}
-
-pub fn new(filepath: String) -> Result(Subject(Control), String) {
-  use _ <- result.try(
   case simplifile.is_file(filepath) {
     Ok(True) -> Ok(Nil)
     _ -> simplifile.create_file(filepath)
   }
   |> result.map_error(fn(e) {
     "Could not access or create log file: " <> string.inspect(e)
-    }),
-  )
-
-  actor.new(State(filepath:))
-  |> actor.on_message(handle_message)
-  |> actor.start
-  |> result.map_error(fn(start_error) {
-    "Could not start logger: " <> string.inspect(start_error)
   })
-  |> result.map(fn(started) { started.data })
 }
 
-fn handle_message(state: State, control: Control) -> actor.Next(State, Control) {
+pub fn log(content: String) -> Nil {
-  case control {
-    control.Write(content) -> {
   let log_line =
     timestamp.system_time()
     |> timestamp.to_rfc3339(calendar.utc_offset)
@@ -43,16 +25,6 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
     <> "\n"
 
   // Ignore any logging errors
-      let _ = simplifile.append(state.filepath, log_line)
+  let _ = simplifile.append(filepath, log_line)
-      actor.continue(state)
+  Nil
-    }
-    control.Exit(reply_to) -> {
-      process.send(reply_to, Nil)
-      actor.stop()
-    }
-  }
-}
-
-pub fn log(logger: Subject(Control), content: String) -> Nil {
-  process.send(logger, control.Write(content))
 }

src/musicplayer/musicplayer.gleam

@@ -5,7 +5,6 @@ import gleam/string
 
 import musicplayer/control.{type Control}
 import musicplayer/input/key.{type Key}
-import musicplayer/logging/control as logging_control
 import musicplayer/logging/logging
 import musicplayer/mpv/control as mpv_control
 import musicplayer/time/time
@@ -25,14 +24,12 @@ type State {
   State(
     mode: Mode,
     input: Input,
-    logger: Subject(logging_control.Control),
     ui: Subject(ui_control.Control),
     mpv: Subject(mpv_control.Control),
   )
 }
 
 pub fn new(
-  logger: Subject(logging_control.Control),
   ui: Subject(ui_control.Control),
   mpv: Subject(mpv_control.Control),
   input_keys_name: Name(Key),
@@ -42,14 +39,14 @@ pub fn new(
   let input = Input(False, "")
 
   case
-    actor.new(State(Idle, input, logger, ui, mpv))
+    actor.new(State(Idle, input, ui, mpv))
     |> actor.on_message(handle_message)
     |> actor.start
   {
     Error(start_error) ->
       Error("Could not start actor: " <> string.inspect(start_error))
     Ok(actor.Started(pid:, data: musicplayer)) -> {
-      logging.log(logger, "musicplayer - started")
+      logging.log("musicplayer - started")
       process.spawn(fn() {
         let assert Ok(_) = process.register(process.self(), input_keys_name)
         handle_key(musicplayer, input_keys)
@@ -65,7 +62,7 @@ pub fn new(
 fn handle_message(state: State, control: Control) -> actor.Next(State, Control) {
   case control {
     control.Search -> {
-      logging.log(state.logger, "musicplayer - initiating search")
+      logging.log("musicplayer - initiating search")
 
       update_search(state.ui, "searching: ")
 
@@ -79,7 +76,7 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
     }
 
     control.Raw(content) -> {
-      logging.log(state.logger, "musicplayer - recieved raw input: " <> content)
+      logging.log("musicplayer - recieved raw input: " <> content)
 
       let content = case state.mode {
         Idle -> state.input.content
@@ -93,7 +90,7 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
       actor.continue(State(..state, input: Input(..state.input, content:)))
     }
     control.Backspace -> {
-      logging.log(state.logger, "musicplayer - recieved backspace")
+      logging.log("musicplayer - recieved backspace")
 
       let content = case state.mode {
         Idle -> state.input.content
@@ -103,7 +100,6 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
     }
     control.Return -> {
       logging.log(
-        state.logger,
         "musicplayer - recieved return. `input.capture`: "
         <> "'"
         <> state.input.content
@@ -123,26 +119,21 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
     }
 
     control.TogglePlayPause -> {
-      logging.log(state.logger, "musicplayer - toggling play/pause")
+      logging.log("musicplayer - toggling play/pause")
 
       process.send(state.mpv, mpv_control.TogglePlayPause)
       update_playback_time(state.mpv, state.ui)
       actor.continue(state)
     }
     control.Exit -> {
-      logging.log(state.logger, "musicplayer - initiating musicplayer shutdown")
+      logging.log("musicplayer - initiating musicplayer shutdown")
       // Close `mpv` socket
       process.call(state.mpv, 1000, fn(reply_to) { mpv_control.Exit(reply_to) })
 
       // Reset terminal state (show cursor etc.)
       process.call(state.ui, 1000, fn(reply_to) { ui_control.Exit(reply_to) })
 
-      logging.log(state.logger, "musicplayer - stopped")
+      logging.log("musicplayer - stopped")
-
-      // Close logger (NOOP)
-      process.call(state.logger, 1000, fn(reply_to) {
-        logging_control.Exit(reply_to)
-      })
 
       actor.stop()
     }

src/musicplayer/ui/control.gleam

@@ -3,6 +3,7 @@ import gleam/erlang/process.{type Subject}
 import musicplayer/ui/layout.{type Section}
 
 pub type Control {
+  UpdateDimensions(width: Int, height: Int)
   UpdateState(section: Section, content: String)
 
   Exit(reply_to: Subject(Nil))

src/musicplayer/ui/internal.gleam

@@ -7,9 +7,13 @@ pub fn clear_screen() -> Nil {
   io.print("\u{001B}[2J\u{001B}[H")
 }
 
-pub fn print_at(text: String, x: Int, y: Int) -> Nil {
+pub fn chars_at(chars: String, x: Int, y: Int) -> String {
   let seq = "\u{001B}[" <> int.to_string(y) <> ";" <> int.to_string(x) <> "H"
-  io.print(seq <> text)
+  seq <> chars
+}
+
+pub fn print(chars: String) -> Nil {
+  io.print(chars)
 }
 
 pub fn hide_cursor() -> Nil {
@@ -19,3 +23,13 @@ pub fn hide_cursor() -> Nil {
 pub fn show_cursor() -> Nil {
   io.print("\u{001B}[?25h")
 }
+
+pub type Enotsup
+
+// https://www.erlang.org/doc/apps/stdlib/io.html#rows/0
+@external(erlang, "io", "rows")
+pub fn io_get_rows() -> Result(Int, Enotsup)
+
+// https://www.erlang.org/doc/apps/stdlib/io.html#columns/0
+@external(erlang, "io", "columns")
+pub fn io_get_columns() -> Result(Int, Enotsup)

src/musicplayer/ui/layout.gleam

@@ -1,7 +1,11 @@
 import gleam/dict
+import gleam/list
+import gleam/string_tree.{type StringTree}
+
+import musicplayer/ui/internal
 
 pub type Layout {
-  Layout(nodes: dict.Dict(Section, Node))
+  Layout(width: Int, height: Int, nodes: dict.Dict(Section, Node))
 }
 
 pub type Section {
@@ -31,7 +35,7 @@ pub fn new() -> Layout {
       #(PlaybackTime, Node(content: "00:00", x: 1, y: 2, children: [])),
     ])
 
-  Layout(nodes: nodes)
+  Layout(0, 0, nodes: nodes)
 }
 
 pub fn update_section(
@@ -42,10 +46,45 @@ pub fn update_section(
   case dict.get(layout.nodes, section) {
     Error(_) -> layout
     Ok(node) ->
-      Layout(nodes: dict.insert(
+      Layout(
+        ..layout,
+        nodes: dict.insert(
           layout.nodes,
           section,
           Node(..node, content: content),
-      ))
+        ),
+      )
+  }
+}
+
+pub fn update_dimensions(layout: Layout, width: Int, height: Int) -> Layout {
+  Layout(..layout, width:, height:)
+}
+
+pub fn render(layout: Layout, from: Section) -> Nil {
+  string_tree.new()
+  |> render_loop(layout, from, _)
+  |> string_tree.to_string
+  |> internal.print
+}
+
+pub fn render_loop(
+  layout: Layout,
+  from: Section,
+  into: StringTree,
+) -> StringTree {
+  case dict.get(layout.nodes, from) {
+    Error(_) -> into
+    Ok(node) -> {
+      let parent =
+        string_tree.append(
+          into,
+          internal.chars_at(node.content, node.x, node.y),
+        )
+
+      list.fold(node.children, parent, fn(into_acc, child) {
+        render_loop(layout, child, into_acc)
+      })
+    }
   }
 }

src/musicplayer/ui/ui.gleam

@@ -1,12 +1,13 @@
-import gleam/dict
 import gleam/erlang/process.{type Subject}
+import gleam/int
 import gleam/list
 import gleam/otp/actor
 import gleam/string
 
+import musicplayer/logging/logging
 import musicplayer/ui/control.{type Control}
-import musicplayer/ui/internal as ui_internal
+import musicplayer/ui/internal
-import musicplayer/ui/layout.{type Layout, type Section}
+import musicplayer/ui/layout.{type Layout}
 
 pub type State(redraw, content) {
   State(redraw: Subject(Layout), layout: Layout)
@@ -26,11 +27,16 @@ pub fn new() -> Result(Subject(Control), String) {
     Error(start_error) ->
       Error("Could not start actor: " <> string.inspect(start_error))
     Ok(actor.Started(data: ui, ..)) -> {
+      process.spawn(fn() {
+        let update_dimensions_interval_ms = 300
+        update_dimensions_on_interval(ui, update_dimensions_interval_ms)
+      })
+
       process.spawn(fn() {
         let assert Ok(_) = process.register(process.self(), redraw_name)
 
-        ui_internal.clear_screen()
+        internal.clear_screen()
-        ui_internal.hide_cursor()
+        internal.hide_cursor()
 
         redraw_on_update_loop(redraw)
       })
@@ -45,6 +51,27 @@ fn handle_message(
   control: Control,
 ) -> actor.Next(State(redraw, layout), Control) {
   case control {
+    control.UpdateDimensions(width, height) -> {
+      let current_dimensions = #(state.layout.width, state.layout.height)
+
+      case #(width, height) == current_dimensions {
+        True -> actor.continue(state)
+        False -> {
+          [width, height]
+          |> list.map(int.to_string)
+          |> string.join(" ")
+          |> string.append("ui - updating dimensions: ", _)
+          |> logging.log
+
+          actor.continue(
+            State(
+              ..state,
+              layout: layout.update_dimensions(state.layout, width, height),
+            ),
+          )
+        }
+      }
+    }
     control.UpdateState(section, content) -> {
       let layout = layout.update_section(state.layout, section, content)
       let state = State(..state, layout:)
@@ -54,7 +81,7 @@ fn handle_message(
     }
 
     control.Exit(reply_to) -> {
-      ui_internal.show_cursor()
+      internal.show_cursor()
       process.send(reply_to, Nil)
       actor.stop()
     }
@@ -64,18 +91,20 @@ fn handle_message(
 fn redraw_on_update_loop(redraw: Subject(Layout)) -> Nil {
   let layout = process.receive_forever(redraw)
 
-  ui_internal.clear_screen()
+  internal.clear_screen()
-  render_layout(layout, layout.Root)
+  layout.render(layout, layout.Root)
 
   redraw_on_update_loop(redraw)
 }
 
-fn render_layout(layout: Layout, from: Section) -> Nil {
+fn update_dimensions_on_interval(ui: Subject(Control), interval_ms: Int) {
-  case dict.get(layout.nodes, from) {
+  case internal.io_get_columns(), internal.io_get_rows() {
-    Error(_) -> Nil
+    Ok(width), Ok(height) -> {
-    Ok(node) -> {
+      process.send(ui, control.UpdateDimensions(width, height))
-      list.each(node.children, fn(child) { render_layout(layout, child) })
-      ui_internal.print_at(node.content, node.x, node.y)
     }
+    _, _ -> logging.log("ui - failed to update dimensions")
   }
+
+  process.sleep(interval_ms)
+  update_dimensions_on_interval(ui, interval_ms)
 }

test/musicplayer/mpv/mpv_test.gleam

@@ -1,6 +1,6 @@
 import gleeunit
 
-import musicplayer/mpv/internal as control_internal
+import musicplayer/mpv/internal
 
 pub fn main() -> Nil {
   gleeunit.main()
@@ -10,6 +10,6 @@ pub fn parse_playback_time_test() {
   let json_string =
     "{\"data\":\"123.456789\",\"request_id\":0,\"error\":\"success\"}\n"
 
-  let assert Ok(data) = control_internal.parse_playback_time(json_string)
+  let assert Ok(data) = internal.parse_playback_time(json_string)
   assert data == 123.456789
 }