#!/usr/bin/env python3
#
# Copyright (c) 2018-2020 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
#
# Download or build previous releases.
# Needs curl and tar to download a release, or the build dependencies when
# building a release.

import argparse
import contextlib
from fnmatch import fnmatch
import os
from pathlib import Path
import re
import shutil
import subprocess
import sys
import hashlib


SHA256_SUMS = {
"d40f18b4e43c6e6370ef7db9131f584fbb137276ec2e3dba67a4b267f81cb644": "bitcoin-0.15.2-aarch64-linux-gnu.tar.gz",
"54fb877a148a6ad189a1e1ab1ff8b11181e58ff2aaf430da55b3fd46ae549a6b": "bitcoin-0.15.2-arm-linux-gnueabihf.tar.gz",
"2b843506c3f1af0eeca5854a920264f9a829f02d0d50328005950ddcbe88874d": "bitcoin-0.15.2-i686-pc-linux-gnu.tar.gz",
"87e9340ff3d382d543b2b69112376077f0c8b4f7450d372e83b68f5a1e22b2df": "bitcoin-0.15.2-osx64.tar.gz",
"566be44190fd76daa01f13d428939dadfb8e3daacefc8fa17f433cad28f73bd5": "bitcoin-0.15.2-x86_64-linux-gnu.tar.gz",

"0768c6c15caffbaca6524824c9563b42c24f70633c681c2744649158aa3fd484": "bitcoin-0.16.3-aarch64-linux-gnu.tar.gz",
"fb2818069854a6ad20ea03b28b55dbd35d8b1f7d453e90b83eace5d0098a2a87": "bitcoin-0.16.3-arm-linux-gnueabihf.tar.gz",
"75a537844313b0a84bdb61ffcdc5c4ce19a738f7ddf71007cd2edf664efd7c37": "bitcoin-0.16.3-i686-pc-linux-gnu.tar.gz",
"78c3bff3b619a19aed575961ea43cc9e142959218835cf51aede7f0b764fc25d": "bitcoin-0.16.3-osx64.tar.gz",
"5d422a9d544742bc0df12427383f9c2517433ce7b58cf672b9a9b17c2ef51e4f": "bitcoin-0.16.3-x86_64-linux-gnu.tar.gz",

"5a6b35d1a348a402f2d2d6ab5aed653a1a1f13bc63aaaf51605e3501b0733b7a": "bitcoin-0.17.2-aarch64-linux-gnu.tar.gz",
"d1913a5d19c8e8da4a67d1bd5205d03c8614dfd2e02bba2fe3087476643a729e": "bitcoin-0.17.2-arm-linux-gnueabihf.tar.gz",
"d295fc93f39bbf0fd937b730a93184899a2eb6c3a6d53f3d857cbe77ef89b98c": "bitcoin-0.17.2-i686-pc-linux-gnu.tar.gz",
"a783ba20706dbfd5b47fbedf42165fce70fbbc7d78003305d964f6b3da14887f": "bitcoin-0.17.2-osx64.tar.gz",
"943f9362b9f11130177839116f48f809d83478b4c28591d486ee9a7e35179da6": "bitcoin-0.17.2-x86_64-linux-gnu.tar.gz",

"88f343af72803b851c7da13874cc5525026b0b55e63e1b5e1298390c4688adc6": "bitcoin-0.18.1-aarch64-linux-gnu.tar.gz",
"cc7d483e4b20c5dabd4dcaf304965214cf4934bcc029ca99cbc9af00d3771a1f": "bitcoin-0.18.1-arm-linux-gnueabihf.tar.gz",
"989e847b3e95fc9fedc0b109cae1b4fa43348f2f712e187a118461876af9bd16": "bitcoin-0.18.1-i686-pc-linux-gnu.tar.gz",
"b7bbcee7a7540f711b171d6981f939ca8482005fde22689bc016596d80548bb1": "bitcoin-0.18.1-osx64.tar.gz",
"425ee5ec631ae8da71ebc1c3f5c0269c627cf459379b9b030f047107a28e3ef8": "bitcoin-0.18.1-riscv64-linux-gnu.tar.gz",
"600d1db5e751fa85903e935a01a74f5cc57e1e7473c15fd3e17ed21e202cfe5a": "bitcoin-0.18.1-x86_64-linux-gnu.tar.gz",

"3a80431717842672df682bdb619e66523b59541483297772a7969413be3502ff": "bitcoin-0.19.1-aarch64-linux-gnu.tar.gz",
"657f28213823d240dd3324d14829702f9ad6f0710f8bdd1c379cb3c447197f48": "bitcoin-0.19.1-arm-linux-gnueabihf.tar.gz",
"10d1e53208aa7603022f4acc084a046299ab4ccf25fe01e81b3fb6f856772589": "bitcoin-0.19.1-i686-pc-linux-gnu.tar.gz",
"1ae1b87de26487075cd2fd22e0d4ead87d969bd55c44f2f1d873ecdc6147ebb3": "bitcoin-0.19.1-osx64.tar.gz",
"aa7a9563b48aa79252c8e7b6a41c07a5441bd9f14c5e4562cc72720ea6cb0ee5": "bitcoin-0.19.1-riscv64-linux-gnu.tar.gz",
"5fcac9416e486d4960e1a946145566350ca670f9aaba99de6542080851122e4c": "bitcoin-0.19.1-x86_64-linux-gnu.tar.gz"
}

@contextlib.contextmanager
def pushd(new_dir) -> None:
    previous_dir = os.getcwd()
    os.chdir(new_dir)
    try:
        yield
    finally:
        os.chdir(previous_dir)


def download_binary(tag, args) -> int:
    if Path(tag).is_dir():
        if not args.remove_dir:
            print('Using cached {}'.format(tag))
            return 0
        shutil.rmtree(tag)
    Path(tag).mkdir()
    bin_path = 'bin/bitcoin-core-{}'.format(tag[1:])
    match = re.compile('v(.*)(rc[0-9]+)$').search(tag)
    if match:
        bin_path = 'bin/bitcoin-core-{}/test.{}'.format(
            match.group(1), match.group(2))
    tarball = 'bitcoin-{tag}-{platform}.tar.gz'.format(
        tag=tag[1:], platform=args.platform)
    tarballUrl = 'https://bitcoincore.org/{bin_path}/{tarball}'.format(
        bin_path=bin_path, tarball=tarball)

    print('Fetching: {tarballUrl}'.format(tarballUrl=tarballUrl))

    header, status = subprocess.Popen(
        ['curl', '--head', tarballUrl], stdout=subprocess.PIPE).communicate()
    if re.search("404 Not Found", header.decode("utf-8")):
        print("Binary tag was not found")
        return 1

    curlCmds = [
        ['curl', '--remote-name', tarballUrl]
    ]

    for cmd in curlCmds:
        ret = subprocess.run(cmd).returncode
        if ret:
            return ret

    hasher = hashlib.sha256()
    with open(tarball, "rb") as afile:
        hasher.update(afile.read())
    tarballHash = hasher.hexdigest()

    if tarballHash not in SHA256_SUMS or SHA256_SUMS[tarballHash] != tarball:
        print("Checksum did not match")
        return 1
    print("Checksum matched")

    # Extract tarball
    ret = subprocess.run(['tar', '-zxf', tarball, '-C', tag,
                          '--strip-components=1',
                          'bitcoin-{tag}'.format(tag=tag[1:])]).returncode
    if ret:
        return ret

    Path(tarball).unlink()
    return 0


def build_release(tag, args) -> int:
    githubUrl = "https://github.com/bitcoin/bitcoin"
    if args.remove_dir:
        if Path(tag).is_dir():
            shutil.rmtree(tag)
    if not Path(tag).is_dir():
        # fetch new tags
        subprocess.run(
            ["git", "fetch", githubUrl, "--tags"])
        output = subprocess.check_output(['git', 'tag', '-l', tag])
        if not output:
            print('Tag {} not found'.format(tag))
            return 1
    ret = subprocess.run([
        'git', 'clone', githubUrl, tag
    ]).returncode
    if ret:
        return ret
    with pushd(tag):
        ret = subprocess.run(['git', 'checkout', tag]).returncode
        if ret:
            return ret
        host = args.host
        if args.depends:
            with pushd('depends'):
                ret = subprocess.run(['make', 'NO_QT=1']).returncode
                if ret:
                    return ret
                host = os.environ.get(
                    'HOST', subprocess.check_output(['./config.guess']))
        config_flags = '--prefix={pwd}/depends/{host} '.format(
            pwd=os.getcwd(),
            host=host) + args.config_flags
        cmds = [
            './autogen.sh',
            './configure {}'.format(config_flags),
            'make',
        ]
        for cmd in cmds:
            ret = subprocess.run(cmd.split()).returncode
            if ret:
                return ret
        # Move binaries, so they're in the same place as in the
        # release download
        Path('bin').mkdir(exist_ok=True)
        files = ['bitcoind', 'bitcoin-cli', 'bitcoin-tx']
        for f in files:
            Path('src/'+f).rename('bin/'+f)
    return 0


def check_host(args) -> int:
    args.host = os.environ.get('HOST', subprocess.check_output(
        './depends/config.guess').decode())
    if args.download_binary:
        platforms = {
            'x86_64-*-linux*': 'x86_64-linux-gnu',
            'x86_64-apple-darwin*': 'osx64',
        }
        args.platform = ''
        for pattern, target in platforms.items():
            if fnmatch(args.host, pattern):
                args.platform = target
        if not args.platform:
            print('Not sure which binary to download for {}'.format(args.host))
            return 1
    return 0


def main(args) -> int:
    Path(args.target_dir).mkdir(exist_ok=True, parents=True)
    print("Releases directory: {}".format(args.target_dir))
    ret = check_host(args)
    if ret:
        return ret
    if args.download_binary:
        with pushd(args.target_dir):
            for tag in args.tags:
                ret = download_binary(tag, args)
                if ret:
                    return ret
        return 0
    args.config_flags = os.environ.get('CONFIG_FLAGS', '')
    args.config_flags += ' --without-gui --disable-tests --disable-bench'
    with pushd(args.target_dir):
        for tag in args.tags:
            ret = build_release(tag, args)
            if ret:
                return ret
    return 0


if __name__ == '__main__':
    parser = argparse.ArgumentParser(
        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
    parser.add_argument('-r', '--remove-dir', action='store_true',
                        help='remove existing directory.')
    parser.add_argument('-d', '--depends', action='store_true',
                        help='use depends.')
    parser.add_argument('-b', '--download-binary', action='store_true',
                        help='download release binary.')
    parser.add_argument('-t', '--target-dir', action='store',
                        help='target directory.', default='releases')
    parser.add_argument('tags', nargs='+',
                        help="release tags. e.g.: v0.18.1 v0.20.0rc2")
    args = parser.parse_args()
    sys.exit(main(args))
