feat: vtt converting

internal/format/txt/txt.go

@@ -0,0 +1,30 @@
+package txt
+
+import (
+	"fmt"
+	"os"
+
+	"sub-cli/internal/model"
+)
+
+// GenerateFromSubtitle converts our intermediate Subtitle to plain text format
+func GenerateFromSubtitle(subtitle model.Subtitle, filePath string) error {
+	file, err := os.Create(filePath)
+	if err != nil {
+		return fmt.Errorf("error creating TXT file: %w", err)
+	}
+	defer file.Close()
+
+	// Write title if available
+	if subtitle.Title != "" {
+		fmt.Fprintln(file, subtitle.Title)
+		fmt.Fprintln(file)
+	}
+
+	// Write content without timestamps
+	for _, entry := range subtitle.Entries {
+		fmt.Fprintln(file, entry.Text)
+	}
+
+	return nil
+}