u7: wire documented config knobs into runtime

5 files changed, 63 insertions, 8 deletions

diff --git a/internal/image/gemini.go b/internal/image/gemini.go
index 05a2e0e..bd418d5 100644
--- a/internal/image/gemini.go
+++ b/internal/image/gemini.go
@@ -28,9 +28,10 @@ const (
 
 // GeminiConfig holds the settings needed to build a Gemini-backed image provider.
 type GeminiConfig struct {
-	APIKey    string
-	Model     string
-	TextModel string
+	APIKey      string
+	Model       string
+	TextModel   string
+	AspectRatio string
 }
 
 // GeminiProvider implements ImageProvider for Google Gemini image generation.
@@ -104,6 +105,9 @@ func (c *GeminiProvider) Search(ctx context.Context, opts *SearchOptions) ([]Sea
 	}
 
 	aspectRatio := geminiAspectRatio
+	if c.config != nil && strings.TrimSpace(c.config.AspectRatio) != "" {
+		aspectRatio = strings.TrimSpace(c.config.AspectRatio)
+	}
 	if opts.AspectRatio != "" {
 		aspectRatio = opts.AspectRatio
 	}
@@ -164,13 +168,26 @@ func (c *GeminiProvider) IsAvailable() error {
 
 // GenerateImage renders the first generated image to outputFile.
 func (c *GeminiProvider) GenerateImage(ctx context.Context, prompt, outputFile string) error {
-	return c.GenerateImageWithReferences(ctx, prompt, outputFile, nil)
+	return c.GenerateImageWithAspectRatio(ctx, prompt, outputFile, "")
+}
+
+// GenerateImageWithAspectRatio renders the first generated image to outputFile
+// using the configured aspect ratio or the supplied override.
+func (c *GeminiProvider) GenerateImageWithAspectRatio(ctx context.Context, prompt, outputFile string, aspectRatio string) error {
+	return c.GenerateImageWithReferencesAndAspectRatio(ctx, prompt, outputFile, nil, aspectRatio)
 }
 
 // GenerateImageWithReferences renders the first generated image to outputFile,
 // optionally conditioning the model on prior page images so comic pages stay
 // visually consistent across the full PDF.
 func (c *GeminiProvider) GenerateImageWithReferences(ctx context.Context, prompt, outputFile string, refs [][]byte) error {
+	return c.GenerateImageWithReferencesAndAspectRatio(ctx, prompt, outputFile, refs, "")
+}
+
+// GenerateImageWithReferencesAndAspectRatio renders the first generated image
+// to outputFile, optionally conditioning on reference images and overriding the
+// aspect ratio.
+func (c *GeminiProvider) GenerateImageWithReferencesAndAspectRatio(ctx context.Context, prompt, outputFile string, refs [][]byte, aspectRatio string) error {
 	if c == nil {
 		return fmt.Errorf("image provider is nil")
 	}
@@ -187,6 +204,9 @@ func (c *GeminiProvider) GenerateImageWithReferences(ctx context.Context, prompt
 	if len(refs) > 0 {
 		opts.ReferenceImages = refs
 	}
+	if strings.TrimSpace(aspectRatio) != "" {
+		opts.AspectRatio = strings.TrimSpace(aspectRatio)
+	}
 	results, err := c.Search(ctx, opts)
 	if err != nil {
 		return err
diff --git a/internal/image/gemini_attribution.go b/internal/image/gemini_attribution.go
index 2aefeac..15d1bb1 100644
--- a/internal/image/gemini_attribution.go
+++ b/internal/image/gemini_attribution.go
@@ -22,7 +22,11 @@ func (c *GeminiProvider) buildAttribution(result *SearchResult, prompt string) s
 	attribution.WriteString("Image generated by Google Gemini Nano Banana\n\n")
 	fmt.Fprintf(&attribution, "Model: %s\n", c.modelName())
 	fmt.Fprintf(&attribution, "Text model: %s\n", c.textModelName())
-	fmt.Fprintf(&attribution, "Aspect ratio: %s\n", geminiAspectRatio)
+	aspectRatio := geminiAspectRatio
+	if c != nil && c.config != nil && strings.TrimSpace(c.config.AspectRatio) != "" {
+		aspectRatio = strings.TrimSpace(c.config.AspectRatio)
+	}
+	fmt.Fprintf(&attribution, "Aspect ratio: %s\n", aspectRatio)
 	fmt.Fprintf(&attribution, "Size: %dx%d\n", result.Width, result.Height)
 	if result.Description != "" {
 		fmt.Fprintf(&attribution, "Result: %s\n", result.Description)
diff --git a/internal/image/gemini_test.go b/internal/image/gemini_test.go
index 91e0ce4..b605f7a 100644
--- a/internal/image/gemini_test.go
+++ b/internal/image/gemini_test.go
@@ -115,6 +115,34 @@ func TestGeminiProvider_Search_CustomPromptSkipsTextGeneration(t *testing.T) {
 	}
 }
 
+func TestGeminiProvider_UsesConfiguredAspectRatio(t *testing.T) {
+	originalText := geminiGenerateText
+	originalImage := geminiGenerateImage
+	t.Cleanup(func() {
+		geminiGenerateText = originalText
+		geminiGenerateImage = originalImage
+	})
+
+	geminiGenerateText = func(context.Context, *GeminiProvider, string, string, string, float32, int32) (string, error) {
+		t.Fatal("unexpected text generation for configured aspect ratio")
+		return "", nil
+	}
+
+	var gotAspectRatio string
+	geminiGenerateImage = func(_ context.Context, _ *GeminiProvider, prompt, aspectRatio string) ([]byte, string, error) {
+		gotAspectRatio = aspectRatio
+		return mustJPEGBytes(t), "image/jpeg", nil
+	}
+
+	client := NewGeminiProvider(&GeminiConfig{APIKey: "test-key", AspectRatio: "1:1"})
+	if err := client.GenerateImage(context.Background(), "Art style: comic.", t.TempDir()+"/out.png"); err != nil {
+		t.Fatalf("GenerateImage() unexpected error: %v", err)
+	}
+	if got, want := gotAspectRatio, "1:1"; got != want {
+		t.Fatalf("aspect ratio = %q, want %q", got, want)
+	}
+}
+
 func TestGeminiProvider_Search_CustomPromptWithoutTranslationKeepsDescriptionSimple(t *testing.T) {
 	originalText := geminiGenerateText
 	originalImage := geminiGenerateImage
diff --git a/internal/image/registry.go b/internal/image/registry.go
index 2d446e8..abf7917 100644
--- a/internal/image/registry.go
+++ b/internal/image/registry.go
@@ -20,6 +20,7 @@ type GeminiRegistryConfig interface {
 	GoogleAPIKey() string
 	ImageModel() string
 	ImageTextModel() string
+	ComicAspectRatio() string
 }
 
 // Registry resolves provider names to factories.
@@ -96,9 +97,10 @@ func DefaultRegistry() *Registry[GeminiRegistryConfig] {
 	registry := NewRegistry[GeminiRegistryConfig]()
 	registry.Register(Gemini, func(cfg GeminiRegistryConfig) (ImageProvider, error) {
 		geminiProvider := NewGeminiProvider(&GeminiConfig{
-			APIKey:    cfg.GoogleAPIKey(),
-			Model:     cfg.ImageModel(),
-			TextModel: cfg.ImageTextModel(),
+			APIKey:      cfg.GoogleAPIKey(),
+			Model:       cfg.ImageModel(),
+			TextModel:   cfg.ImageTextModel(),
+			AspectRatio: cfg.ComicAspectRatio(),
 		})
 		if err := geminiProvider.IsAvailable(); err != nil {
 			return nil, err
diff --git a/internal/image/types_test.go b/internal/image/types_test.go
index 5916389..3b83a50 100644
--- a/internal/image/types_test.go
+++ b/internal/image/types_test.go
@@ -162,6 +162,7 @@ func (f fakeConfig) ImageProviderName() string { return f.name }
 func (f fakeConfig) GoogleAPIKey() string      { return f.apiKey }
 func (f fakeConfig) ImageModel() string        { return f.model }
 func (f fakeConfig) ImageTextModel() string    { return f.textModel }
+func (f fakeConfig) ComicAspectRatio() string  { return "" }
 
 type customConfig struct {
 	name string