import re

with open('web_app.py', 'r', encoding='utf-8') as f:
    content = f.read()

# Match any broken variant of the multipart yield —
# captures everything between 'yield (b\'--frame' and the closing ')'
# regardless of how the newlines/whitespace got mangled.
pattern = re.compile(
    r"[ \t]*yield\s*\(b'--frame.*?buffer\.tobytes\(\).*?\)",
    re.DOTALL
)

fixed_line = r"        yield (b'--frame\r\n' b'Content-Type: image/jpeg\r\n\r\n' + buffer.tobytes() + b'\r\n')"

match = pattern.search(content)
if match:
    content = pattern.sub(fixed_line, content, count=1)
    with open('web_app.py', 'w', encoding='utf-8') as f:
        f.write(content)
    print(f"Fixed! Replaced:\n  {match.group()!r}\nWith:\n  {fixed_line!r}")
else:
    print("ERROR: Could not find the broken yield statement. Check the file manually.")
    # Print nearby context to help debug
    for i, line in enumerate(content.splitlines(), 1):
        if 'frame' in line or 'tobytes' in line:
            print(f"  Line {i}: {line!r}")