adding error handling to image rendering (#201)

Author: digitalghost-dev

cmd/card/imageviewer.go

@@ -7,6 +7,7 @@ import (
 type ImageModel struct {
 	CardName string
 	ImageURL string
+	Error    error
 }
 
 func (m ImageModel) Init() tea.Cmd {
@@ -29,10 +30,11 @@ func (m ImageModel) View() string {
 }
 
 func ImageRenderer(cardName string, imageURL string) ImageModel {
-	imageData, _ := CardImage(imageURL)
+	imageData, err := CardImage(imageURL)
 
 	return ImageModel{
 		CardName: cardName,
 		ImageURL: imageData,
+		Error:    err,
 	}
 }

cmd/card/imageviewer_test.go

@@ -1,6 +1,11 @@
 package card
 
 import (
+	"image"
+	"image/color"
+	"image/png"
+	"net/http"
+	"net/http/httptest"
 	"testing"
 
 	tea "github.com/charmbracelet/bubbletea"
@@ -94,3 +99,81 @@ func TestImageModel_View_Empty(t *testing.T) {
 		t.Errorf("View() with empty ImageURL should return empty string, got %v", result)
 	}
 }
+
+func TestImageRenderer_Success(t *testing.T) {
+	// Create a test HTTP server that serves a valid PNG image
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		img := image.NewRGBA(image.Rect(0, 0, 10, 10))
+		blue := color.RGBA{R: 0, G: 0, B: 255, A: 255}
+		for y := 0; y < 10; y++ {
+			for x := 0; x < 10; x++ {
+				img.Set(x, y, blue)
+			}
+		}
+
+		w.Header().Set("Content-Type", "image/png")
+		w.WriteHeader(http.StatusOK)
+		_ = png.Encode(w, img)
+	}))
+	defer server.Close()
+
+	model := ImageRenderer("Pikachu", server.URL)
+
+	if model.CardName != "Pikachu" {
+		t.Errorf("ImageRenderer() CardName = %v, want %v", model.CardName, "Pikachu")
+	}
+
+	if model.Error != nil {
+		t.Errorf("ImageRenderer() Error should be nil on success, got %v", model.Error)
+	}
+
+	if model.ImageURL == "" {
+		t.Error("ImageRenderer() ImageURL should not be empty on success")
+	}
+}
+
+func TestImageRenderer_Error(t *testing.T) {
+	// Create a test HTTP server that returns an error
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+	}))
+	defer server.Close()
+
+	model := ImageRenderer("Charizard", server.URL)
+
+	if model.CardName != "Charizard" {
+		t.Errorf("ImageRenderer() CardName = %v, want %v", model.CardName, "Charizard")
+	}
+
+	if model.Error == nil {
+		t.Error("ImageRenderer() Error should not be nil when image fetch fails")
+	}
+
+	if model.ImageURL != "" {
+		t.Errorf("ImageRenderer() ImageURL should be empty on error, got %v", model.ImageURL)
+	}
+}
+
+func TestImageRenderer_InvalidImage(t *testing.T) {
+	// Create a test HTTP server that returns invalid image data
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "image/png")
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte("not a valid image"))
+	}))
+	defer server.Close()
+
+	model := ImageRenderer("Mewtwo", server.URL)
+
+	if model.CardName != "Mewtwo" {
+		t.Errorf("ImageRenderer() CardName = %v, want %v", model.CardName, "Mewtwo")
+	}
+
+	if model.Error == nil {
+		t.Error("ImageRenderer() Error should not be nil when image decoding fails")
+	}
+
+	if model.ImageURL != "" {
+		t.Errorf("ImageRenderer() ImageURL should be empty on error, got %v", model.ImageURL)
+	}
+}