#!/usr/bin/env python
import re
import warnings
from collections import defaultdict
from pathlib import Path

from modelindex.load_model_index import load
from modelindex.models.Result import Result
from tabulate import tabulate

MMPT_ROOT = Path(__file__).absolute().parents[2]
PAPERS_ROOT = Path('papers')  # Path to save generated paper pages.
GITHUB_PREFIX = 'https://github.com/open-mmlab/mmpretrain/blob/main/'
MODELZOO_TEMPLATE = """\
# 模型库统计

在本页面中，我们列举了我们支持的[所有算法](#所有已支持的算法)。你可以点击链接跳转至对应的模型详情页面。

另外，我们还列出了我们提供的所有模型权重文件。你可以使用排序和搜索功能找到需要的模型权重，并使用链接跳转至模型详情页面。

## 所有已支持的算法

* 论文数量：{num_papers}
{type_msg}

* 模型权重文件数量：{num_ckpts}
{paper_msg}

"""  # noqa: E501

METRIC_ALIAS = {
    'Top 1 Accuracy': 'Top-1 (%)',
    'Top 5 Accuracy': 'Top-5 (%)',
}

model_index = load(str(MMPT_ROOT / 'model-index.yml'))


def build_collections(model_index):
    col_by_name = {}
    for col in model_index.collections:
        setattr(col, 'models', [])
        col_by_name[col.name] = col

    for model in model_index.models:
        col = col_by_name[model.in_collection]
        col.models.append(model)
        setattr(model, 'collection', col)
        if model.results is None:
            setattr(model, 'tasks', [])
        else:
            setattr(model, 'tasks', [result.task for result in model.results])


build_collections(model_index)


def count_papers(collections):
    total_num_ckpts = 0
    type_count = defaultdict(int)
    paper_msgs = []

    for collection in collections:
        with open(MMPT_ROOT / collection.readme) as f:
            readme = f.read()
        ckpts = set(x.lower().strip()
                    for x in re.findall(r'\[model\]\((https?.*)\)', readme))
        total_num_ckpts += len(ckpts)
        title = collection.paper['Title']
        papertype = collection.data.get('type', 'Algorithm')
        type_count[papertype] += 1

        readme = PAPERS_ROOT / Path(
            collection.filepath).parent.with_suffix('.md').name
        paper_msgs.append(
            f'\t- [{papertype}] [{title}]({readme}) ({len(ckpts)} ckpts)')

    type_msg = '\n'.join(
        [f'\t- {type_}: {count}' for type_, count in type_count.items()])
    paper_msg = '\n'.join(paper_msgs)

    modelzoo = MODELZOO_TEMPLATE.format(
        num_papers=len(collections),
        num_ckpts=total_num_ckpts,
        type_msg=type_msg,
        paper_msg=paper_msg,
    )

    with open('modelzoo_statistics.md', 'w') as f:
        f.write(modelzoo)


count_papers(model_index.collections)


def generate_paper_page(collection):
    PAPERS_ROOT.mkdir(exist_ok=True)

    # Write a copy of README
    with open(MMPT_ROOT / collection.readme) as f:
        readme = f.read()
    folder = Path(collection.filepath).parent
    copy = PAPERS_ROOT / folder.with_suffix('.md').name

    def replace_link(matchobj):
        # Replace relative link to GitHub link.
        name = matchobj.group(1)
        link = matchobj.group(2)
        if not link.startswith('http'):
            assert (folder / link).exists(), \
                f'Link not found:\n{collection.readme}: {link}'
            rel_link = (folder / link).absolute().relative_to(MMPT_ROOT)
            link = GITHUB_PREFIX + str(rel_link)
        return f'[{name}]({link})'

    content = re.sub(r'\[([^\]]+)\]\(([^)]+)\)', replace_link, readme)
    content = f'---\ngithub_page: /{collection.readme}\n---\n' + content

    def make_tabs(matchobj):
        """modify the format from emphasis black symbol to tabs."""
        content = matchobj.group()
        content = content.replace('<!-- [TABS-BEGIN] -->', '')
        content = content.replace('<!-- [TABS-END] -->', '')

        # split the content by "**{Tab-Name}**""
        splits = re.split(r'^\*\*(.*)\*\*$', content, flags=re.M)[1:]
        tabs_list = []
        for title, tab_content in zip(splits[::2], splits[1::2]):
            title = ':::{tab} ' + title + '\n'
            tab_content = tab_content.strip() + '\n:::\n'
            tabs_list.append(title + tab_content)

        return '::::{tabs}\n' + ''.join(tabs_list) + '::::'

    if '<!-- [TABS-BEGIN] -->' in content and '<!-- [TABS-END] -->' in content:
        # Make TABS block a selctive tabs
        try:
            pattern = r'<!-- \[TABS-BEGIN\] -->([\d\D]*?)<!-- \[TABS-END\] -->'
            content = re.sub(pattern, make_tabs, content)
        except Exception as e:
            warnings.warn(f'Can not parse the TABS, get an error : {e}')

    with open(copy, 'w') as copy_file:
        copy_file.write(content)


for collection in model_index.collections:
    generate_paper_page(collection)


def scatter_results(models):
    model_result_pairs = []
    for model in models:
        if model.results is None:
            result = Result(task=None, dataset=None, metrics={})
            model_result_pairs.append((model, result))
        else:
            for result in model.results:
                model_result_pairs.append((model, result))
    return model_result_pairs


def generate_summary_table(task, model_result_pairs, title=None):
    metrics = set()
    for model, result in model_result_pairs:
        if result.task == task:
            metrics = metrics.union(result.metrics.keys())
    metrics = sorted(list(metrics))

    rows = []
    for model, result in model_result_pairs:
        if result.task != task:
            continue
        name = model.name
        params = f'{model.metadata.parameters / 1e6:.2f}'  # Params
        flops = f'{model.metadata.flops / 1e9:.2f}'  # Params
        readme = Path(model.collection.filepath).parent.with_suffix('.md').name
        page = f'[链接]({PAPERS_ROOT / readme})'
        model_metrics = []
        for metric in metrics:
            model_metrics.append(str(result.metrics.get(metric, '')))

        rows.append([name, params, flops, *model_metrics, page])

    with open('modelzoo_statistics.md', 'a') as f:
        if title is not None:
            f.write(f'\n{title}')
        f.write("""\n```{table}\n:class: model-summary\n""")
        header = [
            '模型',
            '参数量 (M)',
            'Flops (G)',
            *[METRIC_ALIAS.get(metric, metric) for metric in metrics],
            'Readme',
        ]
        table_cfg = dict(
            tablefmt='pipe',
            floatfmt='.2f',
            numalign='right',
            stralign='center')
        f.write(tabulate(rows, header, **table_cfg))
        f.write('\n```\n')


def generate_dataset_wise_table(task, model_result_pairs, title=None):
    dataset_rows = defaultdict(list)
    for model, result in model_result_pairs:
        if result.task == task:
            dataset_rows[result.dataset].append((model, result))

    if title is not None:
        with open('modelzoo_statistics.md', 'a') as f:
            f.write(f'\n{title}')
    for dataset, pairs in dataset_rows.items():
        generate_summary_table(task, pairs, title=f'### {dataset}')


model_result_pairs = scatter_results(model_index.models)

# Generate Pretrain Summary
generate_summary_table(
    task=None,
    model_result_pairs=model_result_pairs,
    title='## 预训练模型',
)

# Generate Image Classification Summary
generate_dataset_wise_table(
    task='Image Classification',
    model_result_pairs=model_result_pairs,
    title='## 图像分类',
)

# Generate Multi-Label Classification Summary
generate_dataset_wise_table(
    task='Multi-Label Classification',
    model_result_pairs=model_result_pairs,
    title='## 图像多标签分类',
)

# Generate Image Retrieval Summary
generate_dataset_wise_table(
    task='Image Retrieval',
    model_result_pairs=model_result_pairs,
    title='## 图像检索',
)