add warnings for exceeding metadata character length

main.go

@@ -26,7 +26,9 @@ import (
 //go:embed res/help.txt
 var helpText string
 
-const segmentExtension = "mkv"
+const SEGMENT_EXTENSION = "mkv"
+const MAX_TITLE_LEN = 100
+const MAX_DESCRIPTION_LEN = 5000
 
 func showHelp() {
 	fmt.Println(helpText)
@@ -194,7 +196,7 @@ func main() {
 	}
 
 	// scan for VOD segments
-	vodFiles, err := scanner.ScanSegments(metadata.FootageDir, segmentExtension)
+	vodFiles, err := scanner.ScanSegments(metadata.FootageDir, SEGMENT_EXTENSION)
 	if err != nil {
 		log.Fatalf("Failed to fetch VOD filenames: %v", err)
 		os.Exit(1)
@@ -202,7 +204,7 @@ func main() {
 	if len(vodFiles) == 0 {
 		log.Fatalf(
 			"Directory contained no VOD files (expecting .%s)",
-			segmentExtension,
+			SEGMENT_EXTENSION,
 		)
 		os.Exit(1)
 	}
@@ -221,21 +223,35 @@ func main() {
 		log.Fatalf("Failed to build video template: %v", err)
 		os.Exit(1)
 	}
+	title, err := yt.BuildTemplate(video, templates.Title)
+	if err != nil {
+		log.Fatalf("Failed to build video title: %v", err)
+		os.Exit(1)
+	}
+	description, err := yt.BuildTemplate(video, templates.Description)
+	if err != nil {
+		log.Fatalf("Failed to build video description: %v", err)
+		os.Exit(1)
+	}
+	if len(title) > 100 {
+		log.Fatalf(
+			"Video title length exceeds %d characters (%d). YouTube may reject this!",
+			MAX_TITLE_LEN,
+			len(video.Title),
+		)
+	}
+	if len(description) > 5000 {
+		log.Fatalf(
+			"Video description length exceeds %d characters (%d). YouTube may reject this!",
+			MAX_DESCRIPTION_LEN,
+			len(description),
+		)
+	}
 	if verbose {
 		enc := json.NewEncoder(os.Stdout)
 		fmt.Printf("\nVideo template: ")
 		enc.Encode(video)
 
-		title, err := yt.BuildTemplate(video, templates.Title)
-		if err != nil {
-			log.Fatalf("Failed to build video title: %v", err)
-			os.Exit(1)
-		}
-		description, err := yt.BuildTemplate(video, templates.Description)
-		if err != nil {
-			log.Fatalf("Failed to build video description: %v", err)
-			os.Exit(1)
-		}
 		fmt.Printf(
 			"\n================================\n\n" +
 			"< TITLE >\n%s\n\n" +