# middleware/path_rewrite_middleware.py
"""
Path Rewrite Middleware

Rewrites request paths for path-based vendor routing.
This allows /vendor/VENDORCODE/shop/products to be routed as /shop/products

MUST run AFTER vendor_context_middleware and BEFORE context_middleware.
"""
import logging
from fastapi import Request
from starlette.datastructures import URL

logger = logging.getLogger(__name__)


async def path_rewrite_middleware(request: Request, call_next):
    """
    Middleware to rewrite request paths for vendor context.

    If vendor_context_middleware set request.state.clean_path, this middleware
    will rewrite the request path to use the clean path instead.

    This allows FastAPI route matching to work correctly with path-based routing.

    Example:
        Original: /vendor/WIZAMART/shop/products
        Clean path: /shop/products
        After rewrite: Request is routed as if path was /shop/products

    MUST run after vendor_context_middleware (which sets clean_path)
    MUST run before context_middleware (which needs to see the clean path)
    """

    # Check if vendor_context_middleware set a clean_path
    if hasattr(request.state, 'clean_path'):
        clean_path = request.state.clean_path
        original_path = request.url.path

        # Only rewrite if clean_path is different from original path
        if clean_path != original_path:
            logger.debug(
                f"[PATH_REWRITE] Rewriting path",
                extra={
                    "original_path": original_path,
                    "clean_path": clean_path,
                    "vendor": getattr(request.state, 'vendor', 'NOT SET'),
                }
            )

            # Rewrite the path by modifying the request's scope
            # This affects how FastAPI's router will see the path
            request.scope['path'] = clean_path

            # Also update request._url to reflect the change
            # This ensures request.url.path returns the rewritten path
            old_url = request.url
            new_url = old_url.replace(path=clean_path)
            request._url = new_url

    # Continue to next middleware/handler
    response = await call_next(request)
    return response