#!/usr/bin/env python3

from collections import ChainMap
from pathlib import Path
import os
import re

import asyncio
import httpx
import portage

async def do_manifest(client, filename, size, url):
    resp = await client.get(f'{url}.sha256.txt', follow_redirects=True)
    resp.raise_for_status()
    sha256 = resp.text.split(' ')[0]
    return (filename, size, sha256)

async def do_api(client, ghauth, tagl):
    owner, repo, tag = tagl
    apiurl = f'https://api.github.com/repos/{owner}/{repo}/releases/tags/{tag}'
    resp = await client.get(apiurl, auth=ghauth, follow_redirects=True)
    resp.raise_for_status()
    return {asset['browser_download_url']: asset['size']
            for asset in resp.json()['assets']}

async def handle(fm):
    tags = set()
    res = r'^https://github.com/([^/]*)/([^/]*)/releases/download/([^/]*)/([^/]*)$'
    rec = re.compile(res)
    for _, urls in fm.items():
        m = re.match(rec, urls[0])
        if m:
            tags.add(m.group(1, 2, 3))

    headers = {'User-Agent': 'gentoo-adoptopenjdk-manifest'}
    async with httpx.AsyncClient(headers=headers) as client:
        if 'GITHUB_USER' in os.environ and 'GITHUB_PASS' in os.environ:
            ghauth = (os.environ['GITHUB_USER'], os.environ['GITHUB_PASS'])
        else:
            ghauth = None

        apijobs = (do_api(client, ghauth, tagl) for tagl in tags)
        assetsizes = ChainMap(*await asyncio.gather(*apijobs))

        manifestjobs = (do_manifest(client, filename, assetsizes[urls[0]], urls[0])
                for filename, urls in fm.items())
        return sorted(await asyncio.gather(*manifestjobs))

def main(pkgdir):
    p = portage.db['/']['porttree'].dbapi
    pkgdir = Path(pkgdir).resolve()
    mytree = str(pkgdir.parents[1])
    cp = str(pkgdir.relative_to(pkgdir.parents[1]))
    cpvs = p.cp_list(cp, mytree=mytree)
    fms = (p.getFetchMap(cpv, mytree=mytree) for cpv in cpvs)
    for filename, size, sha256 in asyncio.run(handle(ChainMap(*fms))):
        print(f'DIST {filename} {size} SHA256 {sha256}')

if __name__ == '__main__':
    main('.')