from urllib.parse import urlencode, urlparse, urlunparse

from django.conf import settings
from django.urls import reverse


def build_canonical_url(request, base_url=None, params=None):

    if base_url is None:
        base_url = request.path
    elif base_url.startswith('/'):
        base_url = base_url
    else:
        parsed = urlparse(base_url)
        base_url = parsed.path + ('?' + parsed.query if parsed.query else '')

    filtered_params = {
        k: v for k, v in (params or {}).items()
        if v not in (None, '', [], {}) and not (k == 'page' and str(v) == '1')
    }

    query_string = urlencode(filtered_params)
    path = base_url
    if query_string:
        path += '?' + query_string

    domain = getattr(settings, 'CANONICAL_URL_DOMAIN', None)
    if domain:
        return domain.rstrip('/') + path

    return request.build_absolute_uri(path)