import random

from log import Log
from config import set_config

log_ = Log()
config_ = set_config()


def video_rank(data, size):
    """
    视频分发排序
    :param data: 各路召回的视频 type-dict {'rov_pool_recall': [], 'flow_pool_recall': []}
    :param size: 请求数
    :return: rank_result
    """
    # 将各路召回的视频按照score从大到小排序
    # ROV召回池
    rov_recall_rank = sorted(data['rov_pool_recall'], key=lambda k: (k.get('rovScore'), 0), reverse=True)
    # 流量池
    flow_recall_rank = sorted(data['flow_pool_recall'], key=lambda k: (k.get('rovScore'), 0), reverse=True)
    # 对各路召回的视频进行去重
    rov_recall_rank, flow_recall_rank = remove_duplicate(rov_recall=rov_recall_rank, flow_recall=flow_recall_rank)
    # 从ROV召回池中获取top k
    if len(rov_recall_rank) > 0:
        rank_result = rov_recall_rank[:config_.K]
        rov_recall_rank = rov_recall_rank[config_.K:]
    elif len(flow_recall_rank) > 0:
        rank_result = flow_recall_rank[:config_.K]
        flow_recall_rank = flow_recall_rank[config_.K:]
    else:
        # 兜底策略
        return None
    if not rov_recall_rank and not flow_recall_rank:
        # 兜底策略
        return None
    # 按概率 p 及score排序获取 size - k 个视频
    i = 0
    while i < size - config_.K:
        # 随机生成[0, 1)浮点数
        rand = random.random()
        if rand < config_.P:
            if flow_recall_rank:
                rank_result.append(flow_recall_rank[0])
                flow_recall_rank.remove(flow_recall_rank[0])
            else:
                rank_result.append(rov_recall_rank[:size - config_.K - i])
                return rank_result
        else:
            if rov_recall_rank:
                rank_result.append(rov_recall_rank[0])
                rov_recall_rank.remove(rov_recall_rank[0])
            else:
                rank_result.append(flow_recall_rank[:size - config_.K - i])
                return rank_result
        i += 1
    return rank_result


def remove_duplicate(rov_recall, flow_recall):
    """
    对多路召回的视频去重
    去重原则：
        如果视频在ROV召回池topK，则保留ROV召回池，否则保留流量池
    :param rov_recall: ROV召回池-已排序
    :param flow_recall: 流量池-已排序
    :return:
    """
    flow_recall_remove = []
    flow_recall_video_ids = [item[0] for item in flow_recall]
    # rov_recall topK
    for item in rov_recall[:config_.K]:
        if item[0] in flow_recall_video_ids:
            flow_recall_remove.append(item[0])
    # other
    for item in rov_recall[config_.K:]:
        if item[0] in flow_recall_video_ids:
            rov_recall.remove(item)
    # flow recall remove
    for item in flow_recall:
        if item[0] in flow_recall_remove:
            flow_recall.remove(item)
    return rov_recall, flow_recall