from django.utils.deprecation import MiddlewareMixin

class FaviconMiddleware(MiddlewareMixin):
    def process_response(self, request, response):
        if 'text/html' in response.get('Content-Type', '') and b'</head>' in response.content:
            icon_link = (
                b"<link rel='icon' href=\"data:image/svg+xml,"
                b"<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 120 120'>"
                b"<text y='96' font-size='96'>\xf0\x9f\xa7\x89</text></svg>\">"
                b"\n"
            )
            # (UTF-8 encoded 🧉 = \xf0\x9f\xa7\x89 in bytes)
            response.content = response.content.replace(b'</head>', icon_link + b'</head>')
        return response