# 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.

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals

import os
import sys
import numpy as np

from ..data.source.voc_loader import pascalvoc_label
from .coco_eval import bbox2out

import logging
logger = logging.getLogger(__name__)

__all__ = [
    'bbox2out', 'get_category_info'
]


def get_category_info(anno_file=None,
                      with_background=True,
                      use_default_label=False):
    if use_default_label or anno_file is None \
            or not os.path.exists(anno_file):
        logger.info("Not found annotation file {}, load "
                    "voc2012 categories.".format(anno_file))
        return vocall_category_info(with_background)
    else:
        logger.info("Load categories from {}".format(anno_file))
        return get_category_info_from_anno(anno_file, with_background)


def get_category_info_from_anno(anno_file, with_background=True):
    """
    Get class id to category id map and category id
    to category name map from annotation file.

    Args:
        anno_file (str): annotation file path
        with_background (bool, default True):
            whether load background as class 0.
    """
    cats = []
    with open(anno_file) as f:
        for line in f.readlines():
            cats.append(line.strip())

    if cats[0] != 'background' and with_background:
        cats.insert(0, 'background')
    if cats[0] == 'background' and not with_background:
        cats = cats[1:]

    clsid2catid = {i: i for i in range(len(cats))}
    catid2name = {i: name for i, name in enumerate(cats)}

    return clsid2catid, catid2name


def vocall_category_info(with_background=True):
    """
    Get class id to category id map and category id
    to category name map of mixup voc dataset

    Args:
        with_background (bool, default True):
            whether load background as class 0.
    """
    label_map = pascalvoc_label(with_background)
    label_map = sorted(label_map.items(), key=lambda x: x[1])
    cats = [l[0] for l in label_map]

    if with_background:
        cats.insert(0, 'background')

    clsid2catid = {i: i for i in range(len(cats))}
    catid2name = {i: name for i, name in enumerate(cats)}

    return clsid2catid, catid2name