feat(tracker): implement saving and loading a song file

tracker/files.go

@@ -0,0 +1,51 @@
+package tracker
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"path/filepath"
+
+	"gopkg.in/yaml.v3"
+
+	"github.com/sqweek/dialog"
+	"github.com/vsariola/sointu"
+)
+
+func (t *Tracker) LoadSongFile() {
+	filename, err := dialog.File().Filter("Sointu YAML song", "yml").Filter("Sointu JSON song", "json").Title("Load song").Load()
+	if err != nil {
+		return
+	}
+	bytes, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return
+	}
+	var song sointu.Song
+	if errJSON := json.Unmarshal(bytes, &song); errJSON != nil {
+		if errYaml := yaml.Unmarshal(bytes, &song); errYaml != nil {
+			return
+		}
+	}
+	t.LoadSong(song)
+}
+
+func (t *Tracker) SaveSongFile() {
+	filename, err := dialog.File().Filter("Sointu YAML song", "yml").Filter("Sointu JSON song", "json").Title("Save song").Save()
+	if err != nil {
+		return
+	}
+	var extension = filepath.Ext(filename)
+	var contents []byte
+	if extension == "json" {
+		contents, err = json.Marshal(t.song)
+	} else {
+		contents, err = yaml.Marshal(t.song)
+	}
+	if err != nil {
+		return
+	}
+	if extension == "" {
+		filename = filename + ".yml"
+	}
+	ioutil.WriteFile(filename, contents, 0644)
+}

tracker/layout.go

@@ -20,6 +20,8 @@ import (
 var upIcon *widget.Icon
 var downIcon *widget.Icon
 var addIcon *widget.Icon
+var loadIcon *widget.Icon
+var saveIcon *widget.Icon
 
 func init() {
 	var err error
@@ -35,6 +37,14 @@ func init() {
 	if err != nil {
 		log.Fatal(err)
 	}
+	loadIcon, err = widget.NewIcon(icons.FileFolder)
+	if err != nil {
+		log.Fatal(err)
+	}
+	saveIcon, err = widget.NewIcon(icons.ContentSave)
+	if err != nil {
+		log.Fatal(err)
+	}
 }
 
 func smallButton(icStyle material.IconButtonStyle) material.IconButtonStyle {
@@ -170,6 +180,14 @@ func (t *Tracker) layoutControls(gtx layout.Context) layout.Dimensions {
 		}
 	}()
 
+	for t.LoadSongFileBtn.Clicked() {
+		t.LoadSongFile()
+	}
+
+	for t.SaveSongFileBtn.Clicked() {
+		t.SaveSongFile()
+	}
+
 	return layout.Flex{Axis: layout.Horizontal}.Layout(gtx,
 		layout.Rigid(t.layoutPatterns(
 			t.song.Tracks,
@@ -190,6 +208,14 @@ func (t *Tracker) layoutControls(gtx layout.Context) layout.Dimensions {
 			iconBtn := enableButton(material.IconButton(t.Theme, t.NewInstrumentBtn, addIcon), t.song.Patch.TotalVoices() < 32)
 			return in.Layout(gtx, iconBtn.Layout)
 		}),
+		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
+			iconBtn := material.IconButton(t.Theme, t.LoadSongFileBtn, loadIcon)
+			return in.Layout(gtx, iconBtn.Layout)
+		}),
+		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
+			iconBtn := material.IconButton(t.Theme, t.SaveSongFileBtn, saveIcon)
+			return in.Layout(gtx, iconBtn.Layout)
+		}),
 	)
 }
 

tracker/tracker.go

@@ -36,6 +36,8 @@ type Tracker struct {
 	BPMDownBtn        *widget.Clickable
 	NewTrackBtn       *widget.Clickable
 	NewInstrumentBtn  *widget.Clickable
+	LoadSongFileBtn   *widget.Clickable
+	SaveSongFileBtn   *widget.Clickable
 	ParameterSliders  []*widget.Float
 	UnitBtns          []*widget.Clickable
 	InstrumentBtns    []*widget.Clickable
@@ -263,6 +265,8 @@ func New(audioContext sointu.AudioContext) *Tracker {
 		BPMDownBtn:       new(widget.Clickable),
 		NewTrackBtn:      new(widget.Clickable),
 		NewInstrumentBtn: new(widget.Clickable),
+		LoadSongFileBtn:  new(widget.Clickable),
+		SaveSongFileBtn:  new(widget.Clickable),
 		setPlaying:       make(chan bool),
 		rowJump:          make(chan int),
 		patternJump:      make(chan int),