from collections import OrderedDict

from goods.models import GoodsChannel


def get_categories():
    "提供商品频道和分类"
    #查询商品频道和分类
    categories=OrderedDict()
    channels=GoodsChannel.objects.order_by("group_id","sequence")
    for channel in channels:
        group_id=channel.group_id

        if group_id not in categories:
            categories[group_id]={"channels":[],"sub_cats":[]}

        cat1=channel.category  #当前频道的类别
        # 追加当前频道的类别
        categories[group_id]["channels"].append({
            "id":cat1.id,
            "name":cat1.name,
            "url":channel.url
        })

        #构建当前类别的子类别
        for cat2 in cat1.subs.all():
            cat2.sub_cats=[]
            for cat3 in cat2.subs.all():
                cat2.sub_cats.append(cat3)
            categories[group_id]["sub_cats"].append(cat2)
    return categories