Add web radio player app as MVP

While streaming to soundbox devices is not supported this MVP is a
working mpv-based GUI to play sound from web radio URLs on a Linux
computer.

3 files changed, 196 insertions, 0 deletions

diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..01240cb
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,16 @@
+module xengineering.eu/soundbox
+
+go 1.22.5
+
+require gioui.org v0.7.1
+
+require (
+	gioui.org/cpu v0.0.0-20210817075930-8d6a761490d2 // indirect
+	gioui.org/shader v1.0.8 // indirect
+	github.com/go-text/typesetting v0.1.1 // indirect
+	golang.org/x/exp v0.0.0-20240707233637-46b078467d37 // indirect
+	golang.org/x/exp/shiny v0.0.0-20240707233637-46b078467d37 // indirect
+	golang.org/x/image v0.18.0 // indirect
+	golang.org/x/sys v0.22.0 // indirect
+	golang.org/x/text v0.16.0 // indirect
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..94dae7e
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,23 @@
+eliasnaur.com/font v0.0.0-20230308162249-dd43949cb42d h1:ARo7NCVvN2NdhLlJE9xAbKweuI9L6UgfTbYb0YwPacY=
+eliasnaur.com/font v0.0.0-20230308162249-dd43949cb42d/go.mod h1:OYVuxibdk9OSLX8vAqydtRPP87PyTFcT9uH3MlEGBQA=
+gioui.org v0.7.1 h1:l7OVj47n1z8acaszQ6Wlu+Rxme+HqF3q8b+Fs68+x3w=
+gioui.org v0.7.1/go.mod h1:5Kw/q7R1BWc5MKStuTNvhCgSrRqbfHc9Dzfjs4IGgZo=
+gioui.org/cpu v0.0.0-20210808092351-bfe733dd3334/go.mod h1:A8M0Cn5o+vY5LTMlnRoK3O5kG+rH0kWfJjeKd9QpBmQ=
+gioui.org/cpu v0.0.0-20210817075930-8d6a761490d2 h1:AGDDxsJE1RpcXTAxPG2B4jrwVUJGFDjINIPi1jtO6pc=
+gioui.org/cpu v0.0.0-20210817075930-8d6a761490d2/go.mod h1:A8M0Cn5o+vY5LTMlnRoK3O5kG+rH0kWfJjeKd9QpBmQ=
+gioui.org/shader v1.0.8 h1:6ks0o/A+b0ne7RzEqRZK5f4Gboz2CfG+mVliciy6+qA=
+gioui.org/shader v1.0.8/go.mod h1:mWdiME581d/kV7/iEhLmUgUK5iZ09XR5XpduXzbePVM=
+github.com/go-text/typesetting v0.1.1 h1:bGAesCuo85nXnEN5LmFMVGAGpGkCPtHrZLi//qD7EJo=
+github.com/go-text/typesetting v0.1.1/go.mod h1:d22AnmeKq/on0HNv73UFriMKc4Ez6EqZAofLhAzpSzI=
+github.com/go-text/typesetting-utils v0.0.0-20231211103740-d9332ae51f04 h1:zBx+p/W2aQYtNuyZNcTfinWvXBQwYtDfme051PR/lAY=
+github.com/go-text/typesetting-utils v0.0.0-20231211103740-d9332ae51f04/go.mod h1:DDxDdQEnB70R8owOx3LVpEFvpMK9eeH1o2r0yZhFI9o=
+golang.org/x/exp v0.0.0-20240707233637-46b078467d37 h1:uLDX+AfeFCct3a2C7uIWBKMJIR3CJMhcgfrUAqjRK6w=
+golang.org/x/exp v0.0.0-20240707233637-46b078467d37/go.mod h1:M4RDyNAINzryxdtnbRXRL/OHtkFuWGRjvuhBJpk2IlY=
+golang.org/x/exp/shiny v0.0.0-20240707233637-46b078467d37 h1:SOSg7+sueresE4IbmmGM60GmlIys+zNX63d6/J4CMtU=
+golang.org/x/exp/shiny v0.0.0-20240707233637-46b078467d37/go.mod h1:3F+MieQB7dRYLTmnncoFbb1crS5lfQoTfDgQy6K4N0o=
+golang.org/x/image v0.18.0 h1:jGzIakQa/ZXI1I0Fxvaa9W7yP25TqT6cHIHn+6CqvSQ=
+golang.org/x/image v0.18.0/go.mod h1:4yyo5vMFQjVjUcVk4jEQcU9MGy/rulF5WvUILseCM2E=
+golang.org/x/sys v0.22.0 h1:RI27ohtqKCnwULzJLqkv897zojh5/DwS/ENaMzUOaWI=
+golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/text v0.16.0 h1:a94ExnEXNtEwYLGJSIUxnWoxoRz/ZcCsV63ROupILh4=
+golang.org/x/text v0.16.0/go.mod h1:GhwF1Be+LQoKShO3cGOHzqOgRrGaYc9AvblQOmPVHnI=
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..5701c72
--- /dev/null
+++ b/main.go
@@ -0,0 +1,157 @@
+package main
+
+import (
+	"context"
+	"image/color"
+	"log"
+	"os"
+	"os/exec"
+	"sync"
+
+	"gioui.org/app"
+	"gioui.org/layout"
+	"gioui.org/op"
+	"gioui.org/text"
+	"gioui.org/unit"
+	"gioui.org/widget"
+	"gioui.org/widget/material"
+)
+
+func main() {
+	ui := NewUi()
+	go func() {
+		err := ui.Run()
+		if err != nil {
+			log.Fatal(err)
+		}
+		os.Exit(0)
+	}()
+	app.Main()
+}
+
+type State struct {
+	sync.Mutex
+	Theme               *material.Theme
+	Title               string
+	UrlEditor           widget.Editor
+	PlayPauseButton     widget.Clickable
+	PlayPauseButtonText string
+	PlayerContext       context.Context
+	PlayerCancel        context.CancelFunc
+}
+
+type Ui struct {
+	Window *app.Window
+	State  State
+}
+
+func NewUi() *Ui {
+	ui := Ui{}
+
+	ui.State.Theme = material.NewTheme()
+
+	ui.Window = new(app.Window)
+	ui.Window.Option(app.Title("soundbox app"))
+
+	ui.State.Title = "soundbox"
+	ui.State.PlayPauseButtonText = "Play"
+
+	return &ui
+}
+
+func (ui *Ui) Cleanup() {
+	ui.State.Lock()
+	defer ui.State.Unlock()
+
+	if ui.State.PlayerCancel != nil {
+		ui.State.PlayerCancel()
+	}
+}
+
+func (ui *Ui) Run() error {
+	defer ui.Cleanup()
+	var ops op.Ops
+	for {
+		switch e := ui.Window.Event().(type) {
+		case app.DestroyEvent:
+			return e.Err
+		case app.FrameEvent:
+			gtx := app.NewContext(&ops, e)
+			ui.HandleInputs(gtx)
+			ui.Layout(gtx)
+			e.Frame(gtx.Ops)
+		}
+	}
+}
+
+func (ui *Ui) HandleInputs(gtx layout.Context) {
+	ui.State.Lock()
+	defer ui.State.Unlock()
+
+	if ui.State.PlayPauseButton.Clicked(gtx) {
+		if ui.State.UrlEditor.ReadOnly {
+			ui.State.PlayerCancel()
+		} else {
+			ui.State.PlayerContext, ui.State.PlayerCancel = context.WithCancel(context.Background())
+			go mpv(ui.State.PlayerContext, ui.State.UrlEditor.Text(), ui)
+		}
+	}
+}
+
+func (ui *Ui) Layout(gtx layout.Context) layout.Dimensions {
+	ui.State.Lock()
+	defer ui.State.Unlock()
+
+	inset := layout.UniformInset(unit.Dp(10))
+
+	flex := layout.Flex{
+		Axis:    layout.Vertical,
+		Spacing: layout.SpaceEnd,
+	}
+
+	h1 := material.H1(ui.State.Theme, ui.State.Title)
+	h1.Color = color.NRGBA{R: 88, G: 88, B: 88, A: 255}
+	h1.Alignment = text.Middle
+
+	editor := material.Editor(ui.State.Theme, &ui.State.UrlEditor, "Audio stream URL")
+	editor.Editor.Alignment = text.Middle
+
+	button := material.Button(ui.State.Theme, &ui.State.PlayPauseButton, ui.State.PlayPauseButtonText)
+
+	return inset.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
+		return flex.Layout(gtx,
+			layout.Rigid(h1.Layout),
+			layout.Rigid(layout.Spacer{Height: unit.Dp(25)}.Layout),
+			layout.Rigid(editor.Layout),
+			layout.Rigid(layout.Spacer{Height: unit.Dp(25)}.Layout),
+			layout.Rigid(button.Layout),
+		)
+	})
+}
+
+func mpv(ctx context.Context, url string, ui *Ui) {
+	setPlayingState := func(isPlaying bool) {
+		ui.State.Lock()
+		defer ui.Window.Invalidate()
+		defer ui.State.Unlock()
+
+		ui.State.UrlEditor.ReadOnly = isPlaying
+		if isPlaying {
+			ui.State.PlayPauseButtonText = "Stop"
+		} else {
+			ui.State.PlayPauseButtonText = "Play"
+		}
+	}
+
+	setPlayingState(true)
+
+	cmd := exec.CommandContext(
+		ctx,
+		"mpv",
+		"--no-video",
+		url,
+	)
+	_ = cmd.Run()
+
+	setPlayingState(false)
+}