from django.conf import settings

from core import db
from core.models import Drug


class QueryError(Exception):
    pass


def parse_size(query_params, sizes):
    if "size" in query_params:
        size = query_params["size"]
        if size not in sizes:
            message = "Size is not permitted"
            message_class = "danger"
            return {"message": message, "class": message_class}
        size = int(size)
    else:
        size = 15

    return size


def parse_source(user, query_params):
    source = None
    if "source" in query_params:
        source = query_params["source"]

        # Check validity of source
        if source not in settings.MAIN_SOURCES:
            message = f"Invalid source: {source}"
            message_class = "danger"
            return {"message": message, "class": message_class}

        if source == "all":
            source = None  # the next block will populate it

    if source:
        sources = [source]
    else:
        # Here we need to populate what "all" means for the user.
        # They may only have access to a subset of the sources.
        # We build a custom source list with ones they have access
        # to, and then remove "all" from the list.
        sources = list(settings.MAIN_SOURCES)

    # Get rid of "all", it's just a meta-source
    if "all" in sources:
        sources.remove("all")

    return sources


def run_query(query_params, tags, size, sources, ranges, sort):
    if "query" in query_params:
        query = query_params["query"]
        results = Drug.objects.filter(name__icontains=query)[:size]
    return results


def drug_query(request, query_params, size=None, tags=None):
    db.add_defaults(query_params)

    print("PARAMS11", query_params)
    print("SIZE", size)
    print("TAGS", tags)

    # S - Size
    if request.user.is_anonymous:
        sizes = settings.MAIN_SIZES_ANON
    else:
        sizes = settings.MAIN_SIZES
    if not size:
        size = parse_size(query_params, sizes)
        if isinstance(size, dict):
            return size

    # S - Source
    sources = parse_source(request.user, query_params)
    if isinstance(sources, dict):
        return sources

    # R - Ranges
    ranges = None

    # S - Sort
    sort = None

    # Q/T - Query/Tags
    result = run_query(query_params, tags, size, sources, ranges, sort)
    rtrn = {
        "object_list": result,
    }
    return rtrn