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

from modelindex.load_model_index import load
from tabulate import tabulate

MMCLS_ROOT = Path(__file__).absolute().parents[2]
PAPERS_ROOT = Path('papers')  # Path to save generated paper pages.
GITHUB_PREFIX = 'https://github.com/open-mmlab/mmclassification/blob/1.x/'
MODELZOO_TEMPLATE = """
# Model Zoo Summary

* Number of papers: {num_papers}
{type_msg}

* Number of checkpoints: {num_ckpts}
{paper_msg}
"""

model_index = load(str(MMCLS_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)


build_collections(model_index)


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

    for collection in collections:
        with open(MMCLS_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(MMCLS_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(MMCLS_ROOT)
            link = GITHUB_PREFIX + str(rel_link)
        return f'[{name}]({link})'

    content = re.sub(r'\[([^\]]+)\]\(([^)]+)\)', replace_link, readme)

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


for collection in model_index.collections:
    generate_paper_page(collection)


def generate_summary_table(models):
    dataset_rows = defaultdict(list)
    for model in models:
        if model.results is None:
            continue
        name = model.name
        params = model.metadata.parameters / 1e6
        flops = model.metadata.flops / 1e9
        result = model.results[0]
        top1 = result.metrics.get('Top 1 Accuracy')
        top5 = result.metrics.get('Top 5 Accuracy')
        readme = Path(model.collection.filepath).parent.with_suffix('.md').name
        page = f'[link]({PAPERS_ROOT / readme})'
        row = [name, params, flops, top1, top5, page]
        dataset_rows[result.dataset].append(row)

    with open('modelzoo_statistics.md', 'a') as f:
        for dataset, rows in dataset_rows.items():
            f.write(f'\n## {dataset}\n')
            f.write("""```{table}\n:class: model-summary\n""")
            header = [
                'Model',
                'Params (M)',
                'Flops (G)',
                'Top-1 (%)',
                'Top-5 (%)',
                'Readme',
            ]
            table_cfg = dict(
                tablefmt='pipe',
                floatfmt='.2f',
                numalign='right',
                stralign='center')
            f.write(tabulate(rows, header, **table_cfg))
            f.write('\n```\n')


generate_summary_table(model_index.models)
