#!/usr/bin/env python3

import argparse
import csv
import json
import os
import shutil
import subprocess
import sys

UNRELEASED = "UNRELEASED"


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 util
    from cloudinit import temp_utils
    from cloudinit import templater

DEBUILD_ARGS = ["-S", "-d"]


def get_release_suffix(release):
    """Given ubuntu release (xenial), return a suffix for package (~16.04.1)"""
    csv_path = "/usr/share/distro-info/ubuntu.csv"
    rels = {}
    # fields are version, codename, series, created, release, eol, eol-server
    if os.path.exists(csv_path):
        with open(csv_path, "r") as fp:
            # version has "16.04 LTS" or "16.10", so drop "LTS" portion.
            rels = {row['series']: row['version'].replace(' LTS', '')
                    for row in csv.DictReader(fp)}
    if release in rels:
        return "~%s.1" % rels[release]
    elif release != UNRELEASED:
        print("missing distro-info-data package, unable to give "
              "per-release suffix.\n")
    return ""


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 write_debian_folder(root, templ_data, cloud_util_deps):
    """Create a debian package directory with all rendered template files."""
    print("Creating a debian/ folder in %r" % (root))

    deb_dir = util.abs_join(root, 'debian')

    # Just copy debian/ dir and then update files
    pdeb_d = util.abs_join(find_root(), 'packages', 'debian')
    subp.subp(['cp', '-a', pdeb_d, deb_dir])

    # Fill in the change log template
    templater.render_to_file(util.abs_join(find_root(),
                             'packages', 'debian', 'changelog.in'),
                             util.abs_join(deb_dir, 'changelog'),
                             params=templ_data)

    # Write out the control file template
    reqs_output = run_helper(
        'read-dependencies', args=['--distro', 'debian'])
    reqs = reqs_output.splitlines()
    test_reqs = run_helper(
        'read-dependencies',
        ['--requirements-file', 'test-requirements.txt',
         '--system-pkg-names']).splitlines()

    requires = ['cloud-utils | cloud-guest-utils'] if cloud_util_deps else []
    # We consolidate all deps as Build-Depends as our package build runs all
    # tests so we need all runtime dependencies anyway.
    # NOTE: python package was moved to the front after debuild -S would fail with
    # 'Please add apropriate interpreter' errors (as in debian bug 861132)
    requires.extend(['python3'] + reqs + test_reqs)
    if templ_data['debian_release'] == 'xenial':
        requires.append('python3-pytest-catchlog')
    elif templ_data['debian_release'] == 'impish':
        requires.remove('dh-systemd')
    templater.render_to_file(util.abs_join(find_root(),
                                           'packages', 'debian', 'control.in'),
                             util.abs_join(deb_dir, 'control'),
                             params={'build_depends': ','.join(requires)})


def write_debian_folder_from_branch(root, templ_data, branch):
    """Import a debian package directory from a branch."""
    print("Importing debian/ from branch %s to %s" % (branch, root))

    p_dumpdeb = subprocess.Popen(
        ["git", "archive", branch, "debian"], stdout=subprocess.PIPE
    )
    subprocess.check_call(
        ["tar", "-v", "-C", root, "-x"],
        stdin=p_dumpdeb.stdout
    )

    print("Adding new entry to debian/changelog")
    full_deb_version = (
        templ_data["version_long"] + "-1~bddeb" + templ_data["release_suffix"]
    )
    subp.subp(
        [
            "dch",
            "--distribution",
            templ_data["debian_release"],
            "--newversion",
            full_deb_version,
            "--controlmaint",
            "Snapshot build.",
        ],
        cwd=root
    )


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


def get_parser():
    """Setup and return an argument parser for bdeb tool."""
    parser = argparse.ArgumentParser()
    parser.add_argument("-v", "--verbose", dest="verbose",
                        help=("run verbosely"
                              " (default: %(default)s)"),
                        default=False,
                        action='store_true')
    parser.add_argument("--cloud-utils", dest="cloud_utils",
                        help=("depend on cloud-utils package"
                              " (default: %(default)s)"),
                        default=False,
                        action='store_true')

    parser.add_argument("--python2", dest="python2",
                        help=("build debs for python2 rather than python3"),
                        default=False, action='store_true')

    parser.add_argument("--init-system", dest="init_system",
                        help=("build deb with INIT_SYSTEM=xxx"
                              " (default: %(default)s"),
                        default=os.environ.get("INIT_SYSTEM", "systemd"))

    parser.add_argument("--release", dest="release",
                        help=("build with changelog referencing RELEASE"),
                        default=UNRELEASED)

    for ent in DEBUILD_ARGS:
        parser.add_argument(ent, dest="debuild_args", action='append_const',
                            const=ent, default=[],
                            help=("pass through '%s' to debuild" % ent))

    parser.add_argument("--sign", default=False, action='store_true',
                        help="sign result. do not pass -us -uc to debuild")

    parser.add_argument("--signuser", default=False, action='store',
                        help="user to sign, see man dpkg-genchanges")

    parser.add_argument("--packaging-branch", nargs="?", metavar="BRANCH",
                        const="ubuntu/devel", type=str,
                        help=(
                            "Import packaging from %(metavar)s instead of"
                            " using the packages/debian/* templates"
                            " (default: %(const)s)"
                        ))

    return parser


def main():
    parser = get_parser()
    args = parser.parse_args()

    if args.packaging_branch:
        try:
            subp.subp(
                [
                    "git",
                    "show-ref",
                    "--quiet",
                    "--verify",
                    "refs/heads/" + args.packaging_branch,
                ]
            )
        except subp.ProcessExecutionError:
            print("Couldn't find branch '%s'." % args.packaging_branch)
            print("You may need to checkout the branch from the git remote.")
            return 1
        try:
            subp.subp(
                [
                    "git",
                    "cat-file",
                    "-e",
                    args.packaging_branch + ":debian/control",
                ]
            )
        except subp.ProcessExecutionError:
            print(
                "Couldn't find debian/control in branch '%s'."
                " Is it a packaging branch?" % args.packaging_branch
            )
            return 1

    if not args.sign:
        args.debuild_args.extend(['-us', '-uc'])

    if args.signuser:
        args.debuild_args.extend(['-e%s' % args.signuser])

    os.environ['INIT_SYSTEM'] = args.init_system

    capture = True
    if args.verbose:
        capture = False

    templ_data = {
        'debian_release': args.release,
        'release_suffix': get_release_suffix(args.release)}

    with temp_utils.tempdir() as tdir:

        # output like 0.7.6-1022-g36e92d3
        ver_data = read_version()
        if ver_data['is_release_branch_ci']:
            # If we're performing CI for a new release branch, we don't yet
            # have the tag required to generate version_long; use version
            # instead.
            ver_data['version_long'] = ver_data['version']

        # This is really only a temporary archive
        # since we will extract it then add in the debian
        # folder, then re-archive it for debian happiness
        tarball = "cloud-init_%s.orig.tar.gz" % ver_data['version_long']
        tarball_fp = util.abs_join(tdir, tarball)
        path = None
        for pd in ("./", "../", "../dl/"):
            if os.path.exists(pd + tarball):
                path = pd + tarball
                print("Using existing tarball %s" % path)
                shutil.copy(path, tarball_fp)
                break
        if path is None:
            print("Creating a temp tarball using the 'make-tarball' helper")
            run_helper('make-tarball',
                       ['--version', ver_data['version_long'],
                        '--output=' + tarball_fp])

        print("Extracting temporary tarball %r" % (tarball))
        cmd = ['tar', '-xvzf', tarball_fp, '-C', tdir]
        subp.subp(cmd, capture=capture)

        xdir = util.abs_join(tdir, "cloud-init-%s" % ver_data['version_long'])
        templ_data.update(ver_data)

        if args.packaging_branch:
            write_debian_folder_from_branch(
                xdir, templ_data, args.packaging_branch
            )
        else:
            write_debian_folder(
                xdir, templ_data, cloud_util_deps=args.cloud_utils
            )

        print("Running 'debuild %s' in %r" % (' '.join(args.debuild_args),
                                              xdir))
        with util.chdir(xdir):
            cmd = ['debuild', '--preserve-envvar', 'INIT_SYSTEM']
            if args.debuild_args:
                cmd.extend(args.debuild_args)
            subp.subp(cmd, capture=capture)

        link_fn = os.path.join(os.getcwd(), 'cloud-init_all.deb')
        link_dsc = os.path.join(os.getcwd(), 'cloud-init.dsc')
        for base_fn in os.listdir(os.path.join(tdir)):
            full_fn = os.path.join(tdir, base_fn)
            if not os.path.isfile(full_fn):
                continue
            shutil.move(full_fn, base_fn)
            print("Wrote %r" % (base_fn))
            if base_fn.endswith('_all.deb'):
                # Add in the local link
                util.del_file(link_fn)
                os.symlink(base_fn, link_fn)
                print("Linked %r to %r" % (base_fn,
                                           os.path.basename(link_fn)))
            if base_fn.endswith('.dsc'):
                util.del_file(link_dsc)
                os.symlink(base_fn, link_dsc)
                print("Linked %r to %r" % (base_fn,
                                           os.path.basename(link_dsc)))

    return 0


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