#! /usr/bin/python3

import argparse
import os
import re
import subprocess
import tempfile

TRANSFORM = {
    "rhbz": "https://bugzilla.redhat.com/{id}",
    "issue": "https://github.com/rpm-software-management/mock/issues/{id}",
    "PR": "https://github.com/rpm-software-management/mock/pull/{id}",
    "commit": "https://github.com/rpm-software-management/mock/commit/{id}",
    "copr_issue": "https://github.com/fedora-copr/copr/issues/{id}",
}

TEMP_FILE = ".Release-Notes-Next.md"

def _arg_parser():
    parser = argparse.ArgumentParser()
    parser.add_argument("--use-version", dest="version")
    group = parser.add_mutually_exclusive_group()
    group.add_argument("--config-only", action="store_true")
    group.add_argument("--mock-only", action="store_true")
    return parser

def _limited_config(opts):
    if not opts.config_only and not opts.mock_only:
        return []
    with tempfile.NamedTemporaryFile(delete=False, dir=".") as config_fd:
        opts.temp_config = config_fd.name
        with open("pyproject.toml", "rb") as fd:
            for line in fd.readlines():
                if b'{ name' not in line:
                    config_fd.write(line)
                    continue
                # skip non-config files
                if opts.config_only and b"config" not in line:
                    continue
                # skip config files
                if opts.mock_only and b"config" in line:
                    continue
                config_fd.write(line)
    return ["--config", opts.temp_config]


def _main():
    options = _arg_parser().parse_args()
    options.temp_config = None
    tc_opts = _limited_config(options)
    if not options.version:
        options.version = "Next"
        tc_opts.append("--keep")
    else:
        tc_opts.append("--yes")

    output_file = os.path.join(f"docs/Release-Notes-{options.version}.md")

    found = set()
    pattern = "|".join(TRANSFORM.keys())
    issues_re = re.compile(r"\[(" + pattern + r")#([0-9a-f]+)\]")


    cmd = ["towncrier", "build", "--version", options.version] + tc_opts
    print(f"Calling {cmd}")
    subprocess.check_call(cmd)

    with open(output_file, "w", encoding="utf8") as fdout:

        fdout.write(f"""---
layout: default
title: Release Notes - Mock {options.version}
---

""")

        if options.version == "Next":
            fdout.write("""\
# Pre-release Mock changelog

Every change in Mock or `mock-core-configs` that deserves some promotion needs
to be mentioned in release notes.  This generated page provides a set of changes
that will land the future version of Mock.  See [how to add
entries](Release-Notes-New-Entry).
""")


        with open(TEMP_FILE, encoding="utf8") as fdorig:
            for line in fdorig:
                fdout.write(line)
                findings = re.findall(issues_re, line)
                if not findings:
                    continue
                for finding in findings:
                    found.add(finding)

        fdout.write("\n")
        for (key, value) in found:
            fdout.write(f"[{key}#{value}]: {TRANSFORM[key].format(id=value)}\n")

        if options.version != "Next":
            subprocess.check_call(["git", "add", output_file])


if __name__ == "__main__":
    # go top-level
    os.chdir(os.path.join(os.path.dirname(__file__), '..'))
    try:
        _main()
    finally:
        try:
            os.unlink(TEMP_FILE)
            subprocess.check_call(["git", "rm", "-f", TEMP_FILE])
        except FileNotFoundError:
            pass