Update generate_qr.py

Error Handling: I added checks to ensure the input file exists before processing. If the file is missing, the script raises a FileNotFoundError with a clear message.
Modularization: I split the code into functions to improve readability and maintainability.
Improved Feedback: I updated the script to provide clearer messages about the process and errors, making it easier to understand and debug.

generate_qr.py

@@ -2,23 +2,57 @@
 import base64
 import qrcode
 import urllib.parse
+import os
 
 # Change this if you want to use decoding file hosted elsewhere
 WEB_URL_PREFIX = "https://amanraox.github.io/share-bits-wirelessly/dl.html"
 
-if len(sys.argv) > 1:
-    in_filename = sys.argv[1]
-    out_filename = in_filename if len(sys.argv) == 2 else sys.argv[2]
-else:
-    print("Usage: python generate_qr.py inputfile [optional output filename]")
-    exit(-1)
+def validate_file(input_filename):
+    """Check if the input file exists and is a valid file."""
+    if not os.path.isfile(input_filename):
+        raise FileNotFoundError(f"The file {input_filename} does not exist.")
+
+def encode_file(input_filename):
+    """Encode the file to base64."""
+    with open(input_filename, "rb") as f:
+        file_data = f.read()
+    return base64.b64encode(file_data).decode('ascii')
 
-with open(in_filename, "rb") as f:
-    file_data = f.read()
-
-b64_file_data = base64.b64encode(file_data).decode('ascii')
-url_file_data = urllib.parse.quote_plus(b64_file_data)
-full_url = f"{WEB_URL_PREFIX}?f={out_filename}#{url_file_data}"
-print("encoded url:", full_url)
-qr_img = qrcode.make(full_url)
-qr_img.save(f"{out_filename}_qr.png")
+def generate_qr_code(url, output_filename):
+    """Generate QR code and save it."""
+    qr_img = qrcode.make(url)
+    qr_img.save(f"{output_filename}_qr.png")
+    print(f"QR code saved as {output_filename}_qr.png")
+
+def main():
+    if len(sys.argv) > 1:
+        input_filename = sys.argv[1]
+        output_filename = input_filename if len(sys.argv) == 2 else sys.argv[2]
+    else:
+        print("Usage: python generate_qr.py inputfile [optional output filename]")
+        exit(-1)
+
+    try:
+        # Validate input file existence
+        validate_file(input_filename)
+
+        # Encode file content to base64
+        b64_file_data = encode_file(input_filename)
+
+        # URL encode the base64 file data
+        url_file_data = urllib.parse.quote_plus(b64_file_data)
+
+        # Generate the full URL
+        full_url = f"{WEB_URL_PREFIX}?f={output_filename}#{url_file_data}"
+        print("Encoded URL:", full_url)
+
+        # Generate QR code and save it
+        generate_qr_code(full_url, output_filename)
+
+    except FileNotFoundError as e:
+        print(e)
+    except Exception as e:
+        print(f"An error occurred: {e}")
+
+if __name__ == "__main__":
+    main()