feat(markdown): do not bother trying to render high res img if terminal does not support it

Author: ploMP4

internal/img/chafa_backend.go

@@ -51,6 +51,10 @@ func NewChafaBackend() *chafaBackend {
 	}
 }
 
+func (b *chafaBackend) SymbolsOnly() bool {
+	return b.detectTerminal().pixelMode == chafa.CHAFA_PIXEL_MODE_SYMBOLS
+}
+
 func (b *chafaBackend) Render(path string, width, height int, symbols bool) (string, error) {
 	var err error
 
@@ -118,15 +122,15 @@ func (b chafaBackend) render(path string, width, height int32, symbols bool) (st
 	return printable.String(), nil
 }
 
-type terminalCapabilities struct {
+type chafaTerminalCapabilities struct {
 	termInfo    *chafa.TermInfo
 	canvasMode  chafa.CanvasMode
 	pixelMode   chafa.PixelMode
 	passthrough chafa.Passthrough
 	symbolMap   *chafa.SymbolMap
 }
 
-func (b chafaBackend) detectTerminal() terminalCapabilities {
+func (b chafaBackend) detectTerminal() chafaTerminalCapabilities {
 	termInfo := chafa.TermDbDetect(chafa.TermDbGetDefault(), os.Environ())
 
 	mode := chafa.TermInfoGetBestCanvasMode(termInfo)
@@ -140,7 +144,7 @@ func (b chafaBackend) detectTerminal() terminalCapabilities {
 	symbolMap := chafa.SymbolMapNew()
 	chafa.SymbolMapAddByTags(symbolMap, chafa.TermInfoGetSafeSymbolTags(termInfo))
 
-	return terminalCapabilities{
+	return chafaTerminalCapabilities{
 		termInfo:    termInfo,
 		canvasMode:  mode,
 		pixelMode:   pixelMode,

internal/img/images.go

@@ -1,6 +1,7 @@
 package img
 
 type ImageBackend interface {
+	SymbolsOnly() bool
 	Render(path string, width, height int, symbols bool) (string, error)
 }
 

internal/markdown/renderer.go

@@ -86,14 +86,17 @@ func (r *Renderer) RenderBytes(in []byte, animating bool) (string, error) {
 				continue
 			}
 
+			if r.options.imgBackend.SymbolsOnly() {
+				b.WriteString(limg)
+				continue
+			}
+
 			himg, err := r.options.imgBackend.Render(n.Path, n.Width, n.Height, false)
 			if err != nil {
 				b.WriteString(fmt.Sprintf("[Error rendering image: %s]", n.Label))
 				continue
 			}
 
-			// TODO: check if terminal supports rendering high res images in the
-			// first place otherwise you will stack two low res images
 			if !animating {
 				b.WriteString(ansi.SaveCursor)
 				b.WriteString(limg)