Use StringTree to store the rendered layout

And print the entire layout at once

gleam.toml

@@ -18,6 +18,7 @@ gleam_otp = ">= 1.2.0 and < 2.0.0"
 gleam_erlang = ">= 1.3.0 and < 2.0.0"
 simplifile = ">= 2.3.1 and < 3.0.0"
 gleam_json = ">= 3.1.0 and < 4.0.0"
+gleam_time = ">= 1.6.0 and < 2.0.0"
 
 [dev-dependencies]
 gleeunit = ">= 1.0.0 and < 2.0.0"

manifest.toml

@@ -7,6 +7,7 @@ packages = [
   { name = "gleam_json", version = "3.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_json", source = "hex", outer_checksum = "44FDAA8847BE8FC48CA7A1C089706BD54BADCC4C45B237A992EDDF9F2CDB2836" },
   { name = "gleam_otp", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_stdlib"], otp_app = "gleam_otp", source = "hex", outer_checksum = "BA6A294E295E428EC1562DC1C11EA7530DCB981E8359134BEABC8493B7B2258E" },
   { name = "gleam_stdlib", version = "0.65.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "7C69C71D8C493AE11A5184828A77110EB05A7786EBF8B25B36A72F879C3EE107" },
+  { name = "gleam_time", version = "1.6.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_time", source = "hex", outer_checksum = "0DF3834D20193F0A38D0EB21F0A78D48F2EC276C285969131B86DF8D4EF9E762" },
   { name = "gleeunit", version = "1.9.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleeunit", source = "hex", outer_checksum = "DA9553CE58B67924B3C631F96FE3370C49EB6D6DC6B384EC4862CC4AAA718F3C" },
   { name = "simplifile", version = "2.3.1", build_tools = ["gleam"], requirements = ["filepath", "gleam_stdlib"], otp_app = "simplifile", source = "hex", outer_checksum = "957E0E5B75927659F1D2A1B7B75D7B9BA96FAA8D0C53EA71C4AD9CD0C6B848F6" },
 ]
@@ -16,5 +17,6 @@ gleam_erlang = { version = ">= 1.3.0 and < 2.0.0" }
 gleam_json = { version = ">= 3.1.0 and < 4.0.0" }
 gleam_otp = { version = ">= 1.2.0 and < 2.0.0" }
 gleam_stdlib = { version = ">= 0.44.0 and < 2.0.0" }
+gleam_time = { version = ">= 1.6.0 and < 2.0.0" }
 gleeunit = { version = ">= 1.0.0 and < 2.0.0" }
 simplifile = { version = ">= 2.3.1 and < 3.0.0" }

src/musicplayer.gleam

@@ -2,11 +2,14 @@ import gleam/erlang/process.{type Name}
 
 import musicplayer/input/input
 import musicplayer/input/key.{type Key}
+import musicplayer/logging/logging
 import musicplayer/mpv/mpv
 import musicplayer/musicplayer
 import musicplayer/ui/ui
 
 pub fn main() -> Nil {
+  let assert Ok(_) = logging.initialize()
+
   let input_keys_name: Name(Key) = process.new_name("input_keys")
   input.new(input_keys_name)
 

src/musicplayer/logging/control.gleam

@@ -0,0 +1,5 @@
+pub type Control {
+  Write(String)
+
+  Exit
+}

src/musicplayer/logging/logging.gleam

@@ -0,0 +1,30 @@
+import gleam/result
+import gleam/string
+import gleam/time/calendar
+import gleam/time/timestamp
+import simplifile
+
+const filepath = "/tmp/musicplayer.log"
+
+pub fn initialize() -> Result(Nil, String) {
+  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)
+  })
+}
+
+pub fn log(content: String) -> Nil {
+  let log_line =
+    timestamp.system_time()
+    |> timestamp.to_rfc3339(calendar.utc_offset)
+    <> ": "
+    <> content
+    <> "\n"
+
+  // Ignore any logging errors
+  let _ = simplifile.append(filepath, log_line)
+  Nil
+}

src/musicplayer/mpv/mpv.gleam

@@ -24,7 +24,7 @@ pub fn new() -> Result(Subject(Control), String) {
         |> actor.start
       {
         Error(start_error) ->
-          Error("Could not start actor: " <> string.inspect(start_error))
+          Error("Could not start mpv: " <> string.inspect(start_error))
         Ok(actor.Started(data: mpv, ..)) -> Ok(mpv)
       }
     }

src/musicplayer/musicplayer.gleam

@@ -2,11 +2,12 @@ import gleam/erlang/process.{type Name, type Pid, type Subject}
 import gleam/otp/actor
 import gleam/result
 import gleam/string
-import musicplayer/time/time
 
 import musicplayer/control.{type Control}
 import musicplayer/input/key.{type Key}
+import musicplayer/logging/logging
 import musicplayer/mpv/control as mpv_control
+import musicplayer/time/time
 import musicplayer/ui/control as ui_control
 import musicplayer/ui/layout
 
@@ -45,6 +46,7 @@ pub fn new(
     Error(start_error) ->
       Error("Could not start actor: " <> string.inspect(start_error))
     Ok(actor.Started(pid:, data: musicplayer)) -> {
+      logging.log("musicplayer - started")
       process.spawn(fn() {
         let assert Ok(_) = process.register(process.self(), input_keys_name)
         handle_key(musicplayer, input_keys)
@@ -60,6 +62,8 @@ pub fn new(
 fn handle_message(state: State, control: Control) -> actor.Next(State, Control) {
   case control {
     control.Search -> {
+      logging.log("musicplayer - initiating search")
+
       update_search(state.ui, "searching: ")
 
       actor.continue(
@@ -72,6 +76,8 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
     }
 
     control.Raw(content) -> {
+      logging.log("musicplayer - recieved raw input: " <> content)
+
       let content = case state.mode {
         Idle -> state.input.content
         Searching -> {
@@ -84,6 +90,8 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
       actor.continue(State(..state, input: Input(..state.input, content:)))
     }
     control.Backspace -> {
+      logging.log("musicplayer - recieved backspace")
+
       let content = case state.mode {
         Idle -> state.input.content
         Searching -> string.drop_end(state.input.content, 1)
@@ -91,6 +99,13 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
       actor.continue(State(..state, input: Input(..state.input, content:)))
     }
     control.Return -> {
+      logging.log(
+        "musicplayer - recieved return. `input.capture`: "
+        <> "'"
+        <> state.input.content
+        <> "'",
+      )
+
       // Note: state.input.content is now the final input, use it
       // before it is reset
       case state.mode {
@@ -104,17 +119,22 @@ fn handle_message(state: State, control: Control) -> actor.Next(State, Control)
     }
 
     control.TogglePlayPause -> {
+      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("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("musicplayer - stopped")
+
       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

@@ -1,19 +1,19 @@
 import gleam/int
 import gleam/io
 
-pub fn print(content: String) -> Nil {
-  io.print(content <> "\n")
-}
-
 // https://en.wikipedia.org/wiki/ANSI_escape_code#Control_Sequence_Introducer_commands
 
 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 {
@@ -23,3 +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.nodes,
-        section,
-        Node(..node, content: content),
-      ))
+      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/layout.{type Layout, type Section}
+import musicplayer/ui/internal
+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()
-        ui_internal.hide_cursor()
+        internal.clear_screen()
+        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()
-  render_layout(layout, layout.Root)
+  internal.clear_screen()
+  layout.render(layout, layout.Root)
 
   redraw_on_update_loop(redraw)
 }
 
-fn render_layout(layout: Layout, from: Section) -> Nil {
-  case dict.get(layout.nodes, from) {
-    Error(_) -> Nil
-    Ok(node) -> {
-      list.each(node.children, fn(child) { render_layout(layout, child) })
-      ui_internal.print_at(node.content, node.x, node.y)
+fn update_dimensions_on_interval(ui: Subject(Control), interval_ms: Int) {
+  case internal.io_get_columns(), internal.io_get_rows() {
+    Ok(width), Ok(height) -> {
+      process.send(ui, control.UpdateDimensions(width, height))
     }
+    _, _ -> 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
 }