#!/usr/bin/env python3

# SPDX-FileCopyrightText: Chris Pressey, the original author of this work, has dedicated it to the public domain.
# For more information, please refer to <https://unlicense.org/>
# SPDX-License-Identifier: Unlicense

from argparse import ArgumentParser
import json
import os
import re
import sys


def load_distributions(distribution_specs):
    distributions = {}
    for distribution_spec in distribution_specs:
        with open(distribution_spec, 'r') as f:
            distributions.update(json.loads(f.read()))

    # For now, this fork is always included...
    distributions.update({
        "OpenZz distribution": {
            "entries": [
                "OpenZz",
            ],
            "fixed-tag": "1.0.4-4ce1",
            "releases": [],
            "reponame": "OpenZz",
        },
    })

    return distributions


def filter_distributions(distributions, for_repohost):
    d = {}
    for key, value in distributions.items():
        repohosts = value.get("repohosts", [])
        if for_repohost in repohosts:
            d[key] = value
    return d


def obtain_infos(distributions):
    infos = {}
    for (key, node) in sorted(distributions.items()):
        repo = node.get('reponame')
        if not repo:
            #print "# skipping {}".format(key)
            continue
        releases = node.get('releases', [])
        new_style = node.get('tag-style', 'old') == 'new'
        tag = 'master'
        fixed_tag = node.get('fixed-tag', None)
        if fixed_tag == 'OMIT':
            continue
        if fixed_tag is not None:
            tag = fixed_tag
        elif releases:
            version = releases[-1]['version']
            revision = releases[-1]['revision']
            if new_style:
                tag = '%s-%s' % (version, revision)
                if revision == '0.0':
                    tag = version
            else:
                version = re.sub(r'\.', r'_', str(version))
                revision = re.sub(r'\.', r'_', str(revision))
                tag = 'rel_%s_%s' % (version, revision)
                if revision == '0_0':
                    tag = 'rel_%s' % version
        infos[key] = (repo, tag)
    return infos


def create_shelf_catalog(distribution_specs, for_repohost=None):
    """Create a shelf catalogue from distribution nodes.

    """

    distributions = load_distributions(distribution_specs)
    if for_repohost:
        distributions = filter_distributions(distributions, for_repohost)
    infos = obtain_infos(distributions)

    lines = []
    for (key, (repo, tag)) in sorted(infos.items()):
        lines.append('%s@%s' % (repo, tag))

    for line in sorted(lines):
        try:
            sys.stdout.write(line.encode('utf-8'))
        except:
            sys.stdout.write(line)
        sys.stdout.write('\n')


def main(args):
    argparser = ArgumentParser()
    argparser.add_argument(
        '--distribution-specs',
        type=str,
        default='distribution/distributions.json',
        help="comma-seperated list of filenames of JSON files that "
             "describe the distributions from which to create the "
             "shelf catalogue file"
    )
    argparser.add_argument(
        '--for-repohost',
        type=str,
        default=None,
        help="generate a catalogue file for only this repohost"
    )

    options = argparser.parse_args(args)
    distribution_specs = [x.strip() for x in options.distribution_specs.split(',')]
    create_shelf_catalog(distribution_specs, for_repohost=options.for_repohost)


if __name__ == '__main__':
    main(sys.argv[1:])