#   Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import sys
import six


def get_p_at_n_in_m(data, n, m, ind):
    pos_score = data[ind][0]
    curr = data[ind:ind + m]
    curr = sorted(curr, key=lambda x: x[0], reverse=True)

    if curr[n - 1][0] <= pos_score:
        return 1
    return 0


def evaluate(file_path):
    data = []
    with open(file_path, 'r') as file:
        for line in file:
            line = line.strip()
            tokens = line.split("\t")

            if len(tokens) != 2:
                continue

            data.append((float(tokens[0]), int(tokens[1])))

    #assert len(data) % 10 == 0

    p_at_1_in_2 = 0.0
    p_at_1_in_10 = 0.0
    p_at_2_in_10 = 0.0
    p_at_5_in_10 = 0.0

    length = len(data) // 10

    for i in six.moves.xrange(0, length):
        ind = i * 10
        assert data[ind][1] == 1

        p_at_1_in_2 += get_p_at_n_in_m(data, 1, 2, ind)
        p_at_1_in_10 += get_p_at_n_in_m(data, 1, 10, ind)
        p_at_2_in_10 += get_p_at_n_in_m(data, 2, 10, ind)
        p_at_5_in_10 += get_p_at_n_in_m(data, 5, 10, ind)

    return (p_at_1_in_2 / length, p_at_1_in_10 / length, p_at_2_in_10 / length,
            p_at_5_in_10 / length)