go: get latest comic on app start

xkcdreader/app.go

@@ -14,14 +14,19 @@
 	"fyne.io/fyne/v2/canvas"
 	"fyne.io/fyne/v2/container"
 	"fyne.io/fyne/v2/layout"
+	"fyne.io/fyne/v2/storage"
 	"fyne.io/fyne/v2/theme"
 	"fyne.io/fyne/v2/widget"
 	"git.dotya.ml/wanderer/go-xkcdreader/cmd"
+	"git.dotya.ml/wanderer/go-xkcdreader/xkcdreader/xkcd"
 )
 
 const appGreeting = "welcome to go-xkcdreader"
 
-var a fyne.App
+var (
+	a           fyne.App
+	latestComic = xkcd.GetLatest()
+)
 
 // RunApp performs sets up and runs the main application.
 func RunApp() {
@@ -96,8 +101,6 @@ func makeTabs() *container.AppTabs {
 }
 
 func makeBrowseUI() *fyne.Container {
-	imgPath := "xkcdreader/assets/comic.png"
-
 	// container for the image and surrounding elements
 	imgC := container.New(
 		layout.NewHBoxLayout(),
@@ -109,7 +112,7 @@ func makeBrowseUI() *fyne.Container {
 			// TODO(me): dynamically replace placeholder text with image once
 			// fetched...
 			// widget.NewLabel("img placeholder"),
-			getImg(imgPath),
+			getImg(latestComic.Img, false),
 		),
 		layout.NewSpacer(),
 		widget.NewButtonWithIcon("", theme.NavigateNextIcon(), func() {
@@ -139,23 +142,70 @@ func makeBrowseUI() *fyne.Container {
 	return browseUI
 }
 
-// get img from filesystem, resize it and return as *canvas.Image.
-func getImg(imgPath string) *canvas.Image {
-	_, err := os.Stat(imgPath)
-	// properly handle error, perhaps panic?...don't panic, I know..
-	if err != nil {
-		log.Println("failed to read file " + imgPath)
-		return canvas.NewImageFromFile("")
+// getComicLatest fetches latest comic, updates latestComic if necessary.
+func getComicLatest() {
+	comic := xkcd.GetLatest()
+
+	if comic == nil {
+		// TODO(me): properly handle the situation (i.e. bail early)
+		log.Println("error getting latest comic")
 	}
 
-	img := canvas.NewImageFromFile(imgPath)
+	// update latesComic, if necessary
+	if latestComic != comic {
+		latestComic = comic
+	}
+}
 
+// get img from filesystem, resize it and return as *canvas.Image.
+func getImg(imgURI string, local bool) *canvas.Image {
+	if local {
+		_, err := os.Stat(imgURI)
+		// properly handle error, perhaps panic?...don't panic, I know..
+		if err != nil {
+			log.Println("failed to read file " + imgURI)
+			return canvas.NewImageFromFile("")
+		}
+
+		img := canvas.NewImageFromFile(imgURI)
+
+		img.SetMinSize(
+			fyne.Size{
+				Height: 383,
+				Width:  273,
+			},
+		)
+
+		img.ScaleMode = canvas.ImageScaleSmooth
+		img.FillMode = canvas.ImageFillContain
+
+		return img
+	}
+
+	preImg, err := storage.ParseURI(imgURI)
+	if err != nil {
+		log.Printf("error parsing comic URI: %q", err.Error())
+	}
+
+	// get the actual image
+	img := canvas.NewImageFromURI(preImg)
+
+	if img.Resource == nil {
+		log.Println("error fetching the image file of the latest comic")
+	}
+
+	// set basic img properties
 	img.SetMinSize(
 		fyne.Size{
-			Height: 383,
-			Width:  273,
+			// subject to change, this is what I consider to be sane defaults
+			// atm...
+			Height: 650,
+			Width:  750,
 		},
 	)
 
+	img.ScaleMode = canvas.ImageScaleSmooth
+	img.FillMode = canvas.ImageFillContain
+
 	return img
 }

xkcdreader/app_test.go

@@ -131,7 +131,7 @@ func TestGetImgMinSize(t *testing.T) {
 		w: 273.0,
 	}
 
-	got := getImg(imgPath)
+	got := getImg(imgPath, true)
 	got.SetMinSize(
 		fyne.Size{
 			Height: 383.0,
@@ -155,7 +155,7 @@ func TestGetImg(t *testing.T) {
 	// this is relative to the test file
 	imgPath := "assets/comic.png"
 
-	got := getImg(imgPath)
+	got := getImg(imgPath, true)
 	got.SetMinSize(
 		fyne.Size{
 			Height: 383.0,
@@ -176,3 +176,49 @@ func TestGetImg(t *testing.T) {
 		t.Fatal("Images differ")
 	}
 }
+
+func TestGetComicLatest(t *testing.T) {
+	want := latestComic
+
+	// attempt comic refresh
+	getComicLatest()
+
+	got := latestComic
+
+	if want.Img != got.Img ||
+		want.Alt != got.Alt ||
+		want.Day != got.Day ||
+		want.Link != got.Link ||
+		want.Month != got.Month ||
+		want.News != got.News ||
+		want.SafeTitle != got.SafeTitle ||
+		want.Title != got.Title ||
+		want.Transcript != got.Transcript ||
+		want.Year != got.Year {
+		t.Error("latestComic contains stale comic, comic data differ")
+	}
+}
+
+func TestGetComicLatest_MinSize(t *testing.T) {
+	want := struct {
+		height float32
+		width  float32
+	}{
+		height: 650.0,
+		width:  750.0,
+	}
+
+	getComicLatest()
+
+	got := getImg(latestComic.Img, false)
+
+	if want.height != got.MinSize().Height {
+		t.Errorf("Latest comic height differs, want: %f, got: %f",
+			want.height, got.MinSize().Height)
+	}
+
+	if want.width != got.MinSize().Width {
+		t.Errorf("Latest comic width differs, want: %f, got: %f",
+			want.width, got.MinSize().Width)
+	}
+}