from __future__ import absolute_import
# -*- coding: utf-8 -*-


# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Library General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.


import os
import tempfile
import shutil
import pipes
import glob
import time
import contextlib

import kobo.log
from kobo.shortcuts import run, force_list
from pungi.util import explode_rpm_package, makedirs, copy_all


class ScmBase(kobo.log.LoggingBase):
    def __init__(self, logger=None):
        kobo.log.LoggingBase.__init__(self, logger=logger)

    @contextlib.contextmanager
    def _temp_dir(self, tmp_dir=None):
        if tmp_dir is not None:
            makedirs(tmp_dir)
        path = tempfile.mkdtemp(prefix="cvswrapper_", dir=tmp_dir)

        yield path

        self.log_debug("Removing %s" % path)
        try:
            shutil.rmtree(path)
        except OSError as ex:
            self.log_warning("Error removing %s: %s" % (path, ex))

    def retry_run(self, cmd, retries=5, timeout=60, **kwargs):
        """
        @param cmd - cmd passed to kobo.shortcuts.run()
        @param retries=5 - attempt to execute n times
        @param timeout=60 - seconds before next try
        @param **kwargs - args passed to kobo.shortcuts.run()
        """

        for n in range(1, retries + 1):
            try:
                self.log_debug("Retrying execution %s/%s of '%s'" % (n, retries, cmd))
                return run(cmd, **kwargs)
            except RuntimeError as ex:
                if n == retries:
                    raise ex
                self.log_debug("Waiting %s seconds to retry execution of '%s'" % (timeout, cmd))
                time.sleep(timeout)

        raise RuntimeError("Something went wrong during execution of '%s'" % cmd)


class FileWrapper(ScmBase):
    def export_dir(self, scm_root, scm_dir, target_dir, scm_branch=None, tmp_dir=None, log_file=None):
        self.log_debug("Exporting directory %s from current working directory..."
                       % (scm_dir))
        if scm_root:
            raise ValueError("FileWrapper: 'scm_root' should be empty.")
        dirs = glob.glob(scm_dir)
        if not dirs:
            raise RuntimeError('No directories matched, can not export.')
        for i in dirs:
            copy_all(i, target_dir)

    def export_file(self, scm_root, scm_file, target_dir, scm_branch=None, tmp_dir=None, log_file=None):
        if scm_root:
            raise ValueError("FileWrapper: 'scm_root' should be empty.")
        self.log_debug("Exporting file %s from current working directory..."
                       % (scm_file))
        files = glob.glob(scm_file)
        if not files:
            raise RuntimeError('No files matched, can not export.')
        for i in files:
            target_path = os.path.join(target_dir, os.path.basename(i))
            shutil.copy2(i, target_path)


class CvsWrapper(ScmBase):
    def export_dir(self, scm_root, scm_dir, target_dir, scm_branch=None, tmp_dir=None, log_file=None):
        scm_dir = scm_dir.lstrip("/")
        scm_branch = scm_branch or "HEAD"
        with self._temp_dir(tmp_dir=tmp_dir) as tmp_dir:
            self.log_debug("Exporting directory %s from CVS %s (branch %s)..."
                           % (scm_dir, scm_root, scm_branch))
            self.retry_run(["/usr/bin/cvs", "-q", "-d", scm_root, "export", "-r", scm_branch, scm_dir],
                           workdir=tmp_dir, show_cmd=True, logfile=log_file)
            copy_all(os.path.join(tmp_dir, scm_dir), target_dir)

    def export_file(self, scm_root, scm_file, target_dir, scm_branch=None, tmp_dir=None, log_file=None):
        scm_file = scm_file.lstrip("/")
        scm_branch = scm_branch or "HEAD"
        with self._temp_dir(tmp_dir=tmp_dir) as tmp_dir:
            target_path = os.path.join(target_dir, os.path.basename(scm_file))
            self.log_debug("Exporting file %s from CVS %s (branch %s)..." % (scm_file, scm_root, scm_branch))
            self.retry_run(["/usr/bin/cvs", "-q", "-d", scm_root, "export", "-r", scm_branch, scm_file],
                           workdir=tmp_dir, show_cmd=True, logfile=log_file)

            makedirs(target_dir)
            shutil.copy2(os.path.join(tmp_dir, scm_file), target_path)


class GitWrapper(ScmBase):
    def export_dir(self, scm_root, scm_dir, target_dir, scm_branch=None, tmp_dir=None, log_file=None):
        scm_dir = scm_dir.lstrip("/")
        scm_branch = scm_branch or "master"

        with self._temp_dir(tmp_dir=tmp_dir) as tmp_dir:
            if "://" not in scm_root:
                scm_root = "file://%s" % scm_root

            self.log_debug("Exporting directory %s from git %s (branch %s)..."
                           % (scm_dir, scm_root, scm_branch))
            cmd = ("/usr/bin/git archive --remote=%s %s %s | tar xf -"
                   % (pipes.quote(scm_root), pipes.quote(scm_branch), pipes.quote(scm_dir)))
            # git archive is not supported by http/https
            # or by smart http https://git-scm.com/book/en/v2/Git-on-the-Server-Smart-HTTP
            if scm_root.startswith("http"):
                cmd = ("/usr/bin/git clone --depth 1 --branch=%s %s %s"
                       % (pipes.quote(scm_branch), pipes.quote(scm_root), pipes.quote(tmp_dir)))
            self.retry_run(cmd, workdir=tmp_dir, show_cmd=True, logfile=log_file)

            copy_all(os.path.join(tmp_dir, scm_dir), target_dir)

    def export_file(self, scm_root, scm_file, target_dir, scm_branch=None, tmp_dir=None, log_file=None):
        scm_file = scm_file.lstrip("/")
        scm_branch = scm_branch or "master"

        with self._temp_dir(tmp_dir=tmp_dir) as tmp_dir:
            target_path = os.path.join(target_dir, os.path.basename(scm_file))

            if "://" not in scm_root:
                scm_root = "file://%s" % scm_root

            self.log_debug("Exporting file %s from git %s (branch %s)..."
                           % (scm_file, scm_root, scm_branch))
            cmd = ("/usr/bin/git archive --remote=%s %s %s | tar xf -"
                   % (pipes.quote(scm_root), pipes.quote(scm_branch), pipes.quote(scm_file)))
            # git archive is not supported by http/https
            # or by smart http https://git-scm.com/book/en/v2/Git-on-the-Server-Smart-HTTP
            if scm_root.startswith("http"):
                cmd = ("/usr/bin/git clone --depth 1 --branch=%s %s %s"
                       % (pipes.quote(scm_branch), pipes.quote(scm_root), pipes.quote(tmp_dir)))
            self.retry_run(cmd, workdir=tmp_dir, show_cmd=True, logfile=log_file)

            makedirs(target_dir)
            shutil.copy2(os.path.join(tmp_dir, scm_file), target_path)


class RpmScmWrapper(ScmBase):
    def _list_rpms(self, pats):
        for pat in force_list(pats):
            for rpm in glob.glob(pat):
                yield rpm

    def export_dir(self, scm_root, scm_dir, target_dir, scm_branch=None, tmp_dir=None, log_file=None):
        for rpm in self._list_rpms(scm_root):
            scm_dir = scm_dir.lstrip("/")
            with self._temp_dir(tmp_dir=tmp_dir) as tmp_dir:
                self.log_debug("Extracting directory %s from RPM package %s..." % (scm_dir, rpm))
                explode_rpm_package(rpm, tmp_dir)

                makedirs(target_dir)
                # "dir" includes the whole directory while "dir/" includes it's content
                if scm_dir.endswith("/"):
                    copy_all(os.path.join(tmp_dir, scm_dir), target_dir)
                else:
                    run("cp -a %s %s/" % (pipes.quote(os.path.join(tmp_dir, scm_dir)),
                                          pipes.quote(target_dir)))

    def export_file(self, scm_root, scm_file, target_dir, scm_branch=None, tmp_dir=None, log_file=None):
        for rpm in self._list_rpms(scm_root):
            scm_file = scm_file.lstrip("/")
            with self._temp_dir(tmp_dir=tmp_dir) as tmp_dir:
                self.log_debug("Exporting file %s from RPM file %s..." % (scm_file, rpm))
                explode_rpm_package(rpm, tmp_dir)

                makedirs(target_dir)
                for src in glob.glob(os.path.join(tmp_dir, scm_file)):
                    dst = os.path.join(target_dir, os.path.basename(src))
                    shutil.copy2(src, dst)


def _get_wrapper(scm_type, *args, **kwargs):
    SCM_WRAPPERS = {
        "file": FileWrapper,
        "cvs": CvsWrapper,
        "git": GitWrapper,
        "rpm": RpmScmWrapper,
    }
    try:
        return SCM_WRAPPERS[scm_type](*args, **kwargs)
    except KeyError:
        raise ValueError("Unknown SCM type: %s" % scm_type)


def get_file_from_scm(scm_dict, target_path, logger=None):
    """
    Copy one or more files from source control to a target path. A list of files
    created in ``target_path`` is returned.

    :param scm_dict:
        A dictionary describing the source control repository; this can
        optionally be a path to a directory on the local filesystem or reference
        an RPM. Supported keys for the dictionary are ``scm``, ``repo``,
        ``file``, and ``branch``. ``scm`` is the type of version control system
        used ('git', 'cvs', 'rpm', etc.), ``repo`` is the URL of the repository
        (or, if 'rpm' is the ``scm``, the package name), ``file`` is either a
        path or list of paths to copy, and ``branch`` is the branch to check
        out, if any.

    :param target_path:
        The destination path for the files being copied.

    :param logger:
        The logger to use for any logging performed.

    Example:
        >>> scm_dict = {
        >>>     'scm': 'git',
        >>>     'repo': 'https://pagure.io/pungi.git',
        >>>     'file': ['share/variants.dtd'],
        >>> }
        >>> target_path = '/tmp/path/'
        >>> get_file_from_scm(scm_dict, target_path)
        ['/tmp/path/share/variants.dtd']
    """
    if isinstance(scm_dict, str):
        scm_type = "file"
        scm_repo = None
        scm_file = os.path.abspath(scm_dict)
        scm_branch = None
    else:
        scm_type = scm_dict["scm"]
        scm_repo = scm_dict["repo"]
        scm_file = scm_dict["file"]
        scm_branch = scm_dict.get("branch", None)

    scm = _get_wrapper(scm_type, logger=logger)

    files_copied = []
    for i in force_list(scm_file):
        tmp_dir = tempfile.mkdtemp(prefix="scm_checkout_")
        scm.export_file(scm_repo, i, scm_branch=scm_branch, target_dir=tmp_dir)
        files_copied += copy_all(tmp_dir, target_path)
        shutil.rmtree(tmp_dir)
    return files_copied


def get_dir_from_scm(scm_dict, target_path, logger=None):
    """
    Copy a directory from source control to a target path. A list of files
    created in ``target_path`` is returned.

    :param scm_dict:
        A dictionary describing the source control repository; this can
        optionally be a path to a directory on the local filesystem or reference
        an RPM. Supported keys for the dictionary are ``scm``, ``repo``,
        ``dir``, and ``branch``. ``scm`` is the type of version control system
        used ('git', 'cvs', 'rpm', etc.), ``repo`` is the URL of the repository
        (or, if 'rpm' is the ``scm``, the package name), ``dir`` is the
        directory to copy, and ``branch`` is the branch to check out, if any.

    :param target_path:
        The destination path for the directory being copied.

    :param logger:
        The logger to use for any logging performed.

    Example:
        >>> scm_dict = {
        >>>     'scm': 'git',
        >>>     'repo': 'https://pagure.io/pungi.git',
        >>>     'dir': 'share,
        >>> }
        >>> target_path = '/tmp/path/'
        >>> get_dir_from_scm(scm_dict, target_path)
        ['/tmp/path/share/variants.dtd', '/tmp/path/share/rawhide-fedora.ks', ...]
    """
    if isinstance(scm_dict, str):
        scm_type = "file"
        scm_repo = None
        scm_dir = os.path.abspath(scm_dict)
        scm_branch = None
    else:
        scm_type = scm_dict["scm"]
        scm_repo = scm_dict.get("repo", None)
        scm_dir = scm_dict["dir"]
        scm_branch = scm_dict.get("branch", None)

    scm = _get_wrapper(scm_type, logger=logger)

    tmp_dir = tempfile.mkdtemp(prefix="scm_checkout_")
    scm.export_dir(scm_repo, scm_dir, scm_branch=scm_branch, target_dir=tmp_dir)
    files_copied = copy_all(tmp_dir, target_path)
    shutil.rmtree(tmp_dir)
    return files_copied