# copyright (c) 2024 PaddlePaddle Authors. All Rights Reserve.
# 
# 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 os
import platform
from collections import defaultdict
from pathlib import Path

import matplotlib.pyplot as plt
import numpy as np
from matplotlib import font_manager
from pycocotools.coco import COCO

from .....utils.fonts import PINGFANG_FONT_FILE_PATH


def deep_analyse(dataset_dir, output):
    """class analysis for dataset"""
    tags = ['train', 'val']
    all_instances = 0
    for tag in tags:
        annotations_path = os.path.abspath(
            os.path.join(dataset_dir, f'annotations/instance_{tag}.json'))
        labels_cnt = defaultdict(list)
        coco = COCO(annotations_path)
        cat_ids = coco.getCatIds()
        for cat_id in cat_ids:
            cat_name = coco.loadCats(ids=cat_id)[0]["name"]
            labels_cnt[cat_name] = labels_cnt[cat_name] + coco.getAnnIds(
                catIds=cat_id)
            all_instances += len(labels_cnt[cat_name])
        if tag == 'train':
            cnts_train = [
                len(cat_ids) for cat_name, cat_ids in labels_cnt.items()
            ]
        elif tag == 'val':
            cnts_val = [
                len(cat_ids) for cat_name, cat_ids in labels_cnt.items()
            ]
    classes = [cat_name for cat_name, cat_ids in labels_cnt.items()]
    sorted_id = sorted(
        range(len(cnts_train)), key=lambda k: cnts_train[k], reverse=True)
    cnts_train_sorted = sorted(cnts_train, reverse=True)
    cnts_val_sorted = [cnts_val[index] for index in sorted_id]
    classes_sorted = [classes[index] for index in sorted_id]
    x = np.arange(len(classes))
    width = 0.5

    # bar
    os_system = platform.system().lower()
    if os_system == "windows":
        plt.rcParams['font.sans-serif'] = 'FangSong'
    else:
        font = font_manager.FontProperties(fname=PINGFANG_FONT_FILE_PATH)
    fig, ax = plt.subplots(figsize=(max(8, int(len(classes) / 5)), 5), dpi=120)
    ax.bar(x, cnts_train_sorted, width=0.5, label='train')
    ax.bar(x + width, cnts_val_sorted, width=0.5, label='val')
    plt.xticks(
        x + width / 2,
        classes_sorted,
        rotation=90,
        fontproperties=None if os_system == "windows" else font)
    ax.set_ylabel('Counts')
    plt.legend()
    fig.tight_layout()
    fig_path = os.path.join(output, "histogram.png")
    fig.savefig(fig_path)
    return {"histogram": os.path.join("check_dataset", "histogram.png")}