feat: use 'center' for image widths 760<x<1800

renderer/image.go

@@ -16,42 +16,49 @@ import (
 	"github.com/yuin/goldmark/util"
 )
 
-// calculateAlign determines the appropriate ac:align value based on width
+// calculateAlign determines the appropriate ac:align value
-// Images >= 760px wide use "wide", otherwise use the configured alignment
+// Images >= 760px must use "center" alignment, smaller images can use configured alignment
 func calculateAlign(configuredAlign string, width string) string {
+	// No alignment configured
 	if configuredAlign == "" {
 		return ""
 	}
 	
-	if width == "" {
+	// Check if image is wide enough to require center alignment
-		return configuredAlign
-	}
-	
-	// Parse width and check if >= 760
-	widthInt, err := strconv.Atoi(width)
-	if err != nil {
-		return configuredAlign
-	}
-	
-	if widthInt >= 760 {
-		return "wide"
-	}
-	
-	return configuredAlign
-}
-
-// calculateLayout determines the appropriate ac:layout value based on alignment and width
-// Images >= 1800px use "full-width", otherwise based on alignment
-func calculateLayout(align string, width string) string {
-	// Check if full-width should be used
 	if width != "" {
 		widthInt, err := strconv.Atoi(width)
-		if err == nil && widthInt >= 1800 {
+		if err == nil && widthInt >= 760 {
-			return "full-width"
+			return "center"
 		}
 	}
 	
-	// Otherwise use layout based on alignment
+	// For images < 760px, use configured alignment
+	return configuredAlign
+}
+
+// calculateLayout determines the appropriate ac:layout value based on width and alignment
+// Images >= 1800px use "full-width", images >= 760px use "wide", otherwise based on alignment
+// Returns empty string if no alignment is configured
+func calculateLayout(align string, width string) string {
+	// If no alignment configured, don't set layout
+	if align == "" {
+		return ""
+	}
+	
+	// Check width thresholds first
+	if width != "" {
+		widthInt, err := strconv.Atoi(width)
+		if err == nil {
+			if widthInt >= 1800 {
+				return "full-width"
+			}
+			if widthInt >= 760 {
+				return "wide"
+			}
+		}
+	}
+	
+	// For images < 760px, use layout based on alignment
 	switch align {
 	case "left":
 		return "align-start"
@@ -59,8 +66,6 @@ func calculateLayout(align string, width string) string {
 		return "center"
 	case "right":
 		return "align-end"
-	case "wide":
-		return "center"
 	default:
 		return ""
 	}

renderer/image_test.go

@@ -10,14 +10,13 @@ func TestCalculateAlign(t *testing.T) {
 		expectedAlign    string
 	}{
 		{"No alignment configured", "", "1000", ""},
-		{"No width available", "center", "", "center"},
+		{"Center alignment small", "center", "500", "center"},
-		{"Below threshold", "center", "500", "center"},
+		{"Left alignment small", "left", "500", "left"},
-		{"At threshold", "center", "760", "wide"},
+		{"Right alignment small", "right", "500", "right"},
-		{"Above threshold", "center", "1000", "wide"},
+		{"Left forced to center at 760px", "left", "760", "center"},
-		{"Left below threshold", "left", "700", "left"},
+		{"Left forced to center above 760px", "left", "1000", "center"},
-		{"Left at threshold", "left", "760", "wide"},
+		{"Right forced to center at 1800px", "right", "1800", "center"},
-		{"Invalid width", "center", "abc", "center"},
+		{"No width provided", "left", "", "left"},
-		{"Large image", "center", "2000", "wide"},
 	}
 
 	for _, tt := range tests {
@@ -37,16 +36,26 @@ func TestCalculateLayout(t *testing.T) {
 		width          string
 		expectedLayout string
 	}{
-		{"Left alignment", "left", "500", "align-start"},
+		// Small images (< 760px) use alignment-based layout
-		{"Center alignment", "center", "500", "center"},
+		{"Left alignment small", "left", "500", "align-start"},
-		{"Right alignment", "right", "500", "align-end"},
+		{"Center alignment small", "center", "500", "center"},
-		{"Wide alignment", "wide", "1000", "center"},
+		{"Right alignment small", "right", "500", "align-end"},
-		{"Full-width threshold", "center", "1800", "full-width"},
+		{"No alignment small", "", "500", ""},
-		{"Above full-width", "left", "2000", "full-width"},
+		
-		{"Below full-width", "center", "1799", "center"},
+		// Medium images (760-1799px) use "wide" layout (must be center align)
-		{"No alignment", "", "1000", ""},
+		{"Center at 760px", "center", "760", "wide"},
-		{"Unknown alignment", "justify", "500", ""},
+		{"Center at 1000px", "center", "1000", "wide"},
+		{"Center at 1799px", "center", "1799", "wide"},
+		
+		// Large images (>= 1800px) use "full-width" layout (must be center align)
+		{"Center at 1800px", "center", "1800", "full-width"},
+		{"Center at 2000px", "center", "2000", "full-width"},
+		
+		// Edge cases
+		{"No width", "center", "", "center"},
 		{"Invalid width", "center", "abc", "center"},
+		{"Empty alignment and width", "", "", ""},
+		{"No alignment configured", "", "1000", ""},
 	}
 
 	for _, tt := range tests {
@@ -67,8 +76,9 @@ func TestCalculateDisplayWidth(t *testing.T) {
 		expectedWidth string
 	}{
 		{"Full-width layout", "2000", "full-width", "1800"},
-		{"Center layout keeps original", "1000", "center", "1000"},
+		{"Wide layout keeps original", "1000", "wide", "1000"},
-		{"Align-start keeps original", "800", "align-start", "800"},
+		{"Center layout keeps original", "800", "center", "800"},
+		{"Align-start keeps original", "500", "align-start", "500"},
 		{"Empty original", "", "center", ""},
 		{"Empty layout", "1000", "", "1000"},
 	}