#!/usr/bin/env python3

import argparse
import glob
import json
import os
import shutil
import sys
import tempfile


def find_root():
    # expected path is in <top_dir>/packages/
    top_dir = os.environ.get("CLOUD_INIT_TOP_D", None)
    if top_dir is None:
        top_dir = os.path.dirname(
            os.path.dirname(os.path.abspath(sys.argv[0])))
    if os.path.isfile(os.path.join(top_dir, 'setup.py')):
        return os.path.abspath(top_dir)
    raise OSError(("Unable to determine where your cloud-init topdir is."
                   " set CLOUD_INIT_TOP_D?"))


if "avoid-pep8-E402-import-not-top-of-file":
    # Use the util functions from cloudinit
    sys.path.insert(0, find_root())
    from cloudinit import subp
    from cloudinit import templater
    from cloudinit import util


# Subdirectories of the ~/rpmbuild dir
RPM_BUILD_SUBDIRS = ['BUILD', 'RPMS', 'SOURCES', 'SPECS', 'SRPMS']


def run_helper(helper, args=None, strip=True):
    if args is None:
        args = []
    cmd = [util.abs_join(find_root(), 'tools', helper)] + args
    (stdout, _stderr) = subp.subp(cmd)
    if strip:
        stdout = stdout.strip()
    return stdout


def read_dependencies(distro):
    """Returns the Python package depedencies from requirements.txt files.

    @returns a tuple of (build_deps, run_deps, test_deps)
    """
    build_deps = run_helper(
        'read-dependencies',args=[
            '--distro', distro, '--build-requires']).splitlines()
    run_deps = run_helper(
        'read-dependencies', args=[
            '--distro', distro, '--runtime-requires']).splitlines()
    test_deps = run_helper(
        'read-dependencies', args=[
            '--requirements-file', 'test-requirements.txt',
            '--system-pkg-names']).splitlines()
    return (build_deps, run_deps, test_deps)


def METHOD_NAME():
    return json.loads(run_helper('read-version', ['--json']))


def generate_spec_contents(args, version_data, tmpl_fn, top_dir, arc_fn):

    # Tmpl params
    subs = {}

    if args.sub_release is not None:
        subs['subrelease'] = str(args.sub_release)
    else:
        subs['subrelease'] = ""

    subs['archive_name'] = arc_fn
    subs['source_name'] = os.path.basename(arc_fn).replace('.tar.gz', '')
    subs.update(version_data)

    # rpm does not like '-' in the Version, so change
    #   X.Y.Z-N-gHASH to X.Y.Z+N.gHASH
    if "-" in version_data.get('version'):
        ver, commits, ghash = version_data['version'].split("-")
        rpm_upstream_version = "%s+%s.%s" % (ver, commits, ghash)
    else:
        rpm_upstream_version = version_data['version']
    subs['rpm_upstream_version'] = rpm_upstream_version

    build_deps, run_deps, test_deps = read_dependencies(distro=args.distro)
    subs['buildrequires'] = build_deps + test_deps
    subs['requires'] = run_deps

    if args.boot == 'sysvinit':
        subs['sysvinit'] = True
    else:
        subs['sysvinit'] = False

    if args.boot == 'systemd':
        subs['systemd'] = True
    else:
        subs['systemd'] = False

    subs['init_sys'] = args.boot
    subs['patches'] = [os.path.basename(p) for p in args.patches]
    return templater.render_from_file(tmpl_fn, params=subs)


def main():

    parser = argparse.ArgumentParser()
    parser.add_argument("-d", "--distro", dest="distro",
                        help="select distro (default: %(default)s)",
                        metavar="DISTRO", default='redhat',
                        choices=('redhat', 'suse'))
    parser.add_argument('--srpm',
                        help='Produce a source rpm',
                        action='store_true')
    parser.add_argument("-b", "--boot", dest="boot",
                        help="select boot type (default: %(default)s)",
                        metavar="TYPE", default='sysvinit',
                        choices=('sysvinit', 'systemd'))
    parser.add_argument("-v", "--verbose", dest="verbose",
                        help=("run verbosely"
                              " (default: %(default)s)"),
                        default=False,
                        action='store_true')
    parser.add_argument('-s', "--sub-release", dest="sub_release",
                        metavar="RELEASE",
                        help=("a 'internal' release number to concat"
                              " with the bzr version number to form"
                              " the final version number"),
                        type=int,
                        default=None)
    parser.add_argument("-p", "--patch", dest="patches",
                        help=("include the following patch when building"),
                        default=[],
                        action='append')
    args = parser.parse_args()
    capture = True
    if args.verbose:
        capture = False

    workdir = None
    try:
        workdir = tempfile.mkdtemp(prefix='rpmbuild')
        os.environ['HOME'] = workdir
        topdir = os.path.join(workdir, 'rpmbuild')
        build_dirs = [os.path.join(topdir, dir)
                      for dir in RPM_BUILD_SUBDIRS]
        util.ensure_dirs(build_dirs)

        version_data = METHOD_NAME()

        # Archive the code
        archive_fn = "cloud-init-%s.tar.gz" % version_data['version_long']
        real_archive_fn = os.path.join(topdir, 'SOURCES', archive_fn)
        archive_fn = run_helper(
            'make-tarball', ['--long', '--output=' + real_archive_fn])
        print("Archived the code in %r" % (real_archive_fn))

        # Form the spec file to be used
        tmpl_fn = util.abs_join(find_root(), 'packages',
                                args.distro, 'cloud-init.spec.in')
        contents = generate_spec_contents(args, version_data, tmpl_fn, topdir,
                                          os.path.basename(archive_fn))
        spec_fn = util.abs_join(topdir, 'SPECS', 'cloud-init.spec')
        util.write_file(spec_fn, contents)
        print("Created spec file at %r" % (spec_fn))
        for p in args.patches:
            util.copy(p, util.abs_join(topdir, 'SOURCES', os.path.basename(p)))

        # Now build it!
        print("Running 'rpmbuild' in %r" % (topdir))

        if args.srpm:
            cmd = ['rpmbuild', '-bs', '--nodeps', spec_fn]
        else:
            cmd = ['rpmbuild', '-ba', spec_fn]

        subp.subp(cmd, capture=capture)

        # Copy the items built to our local dir
        globs = []
        globs.extend(glob.glob("%s/*.rpm" %
                               (util.abs_join(topdir, 'RPMS', 'noarch'))))
        globs.extend(glob.glob("%s/*.rpm" %
                               (util.abs_join(topdir, 'RPMS', 'x86_64'))))
        globs.extend(glob.glob("%s/*.rpm" %
                               (util.abs_join(topdir, 'RPMS'))))
        globs.extend(glob.glob("%s/*.rpm" %
                               (util.abs_join(topdir, 'SRPMS'))))
        for rpm_fn in globs:
            tgt_fn = util.abs_join(os.getcwd(), os.path.basename(rpm_fn))
            shutil.move(rpm_fn, tgt_fn)
            print("Wrote out %s package %r" % (args.distro, tgt_fn))
    finally:
        if workdir is not None:
            shutil.rmtree(workdir)

    return 0


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