# -*- coding: utf-8 -*-

# utils.py - a module with support methods for centpkg

#

# Copyright (C) 2021 Red Hat Inc.

# Author(s): Ondrej Nosek <onosek@redhat.com>

#

# 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; either version 2 of the License, or (at your

# option) any later version.  See http://www.gnu.org/copyleft/gpl.html for

# the full text of the license.

import os

from pathlib import Path

import re

import json

import git

import requests

from pyrpkg import rpkgError

from requests.exceptions import ConnectionError

from six.moves.configparser import NoOptionError, NoSectionError

from six.moves.urllib.parse import quote_plus, urlparse

dist_git_config = None

def do_fork(logger, base_url, token, repo_name, namespace, cli_name):

    """

    Creates a fork of the project.

    :param logger: A logger object

    :param base_url: a string of the URL repository

    :param token: a string of the API token that has rights to make a fork

    :param repo_name: a string of the repository name

    :param namespace: a string determines a type of the repository

    :param cli_name: string of the CLI's name (e.g. centpkg)

    :return: a tuple consisting of whether the fork needed to be created (bool)

        and the fork path (string)

    """

    api_url = '{0}/api/v4'.format(base_url.rstrip('/'))

    project_id = quote_plus("redhat/centos-stream/{0}/{1}".format(namespace, repo_name))

    fork_url = '{0}/projects/{1}/fork'.format(api_url, project_id)

    headers = {

        'PRIVATE-TOKEN': token,

        'Accept': 'application/json',

        'Content-Type': 'application/json'

    }

    # define a new repository name/path to avoid collision with other projects

    safe_name = "centos_{0}_{1}".format(namespace, repo_name)

    payload = json.dumps({

        'name': safe_name,  # name of the project after forking

        'path': safe_name,

    })

    try:

        rv = requests.post(

            fork_url, headers=headers, data=payload, timeout=60)

    except ConnectionError as error:

        error_msg = ('The connection to API failed while trying to '

                     'create a new fork. The error was: {0}'.format(str(error)))

        raise rpkgError(error_msg)

    try:

        # Extract response json for debugging

        rv_json = rv.json()

        logger.debug("GitLab API response: '{0}'".format(rv_json))

    except Exception:

        pass

    if rv.ok:

        fork_id = rv.json()['id']

        try:

            # Unprotect c9s in fork

            rv = requests.delete('{0}/projects/{1}/protected_branches/{2}'.format(api_url, fork_id, 'c9s'), headers=headers)

        except ConnectionError as error:

            error_msg = ('The connection to API failed while trying to unprotect c9s branch'

                         'in the fork. The error was: {0}'.format(str(error)))

            raise rpkgError(error_msg)

        try:

            # Reprotect c9s to disable pushes

            # Only maintainers in gitlab are allowed to push with the following config

            # In CS, every pkg maintainer is considered as a developer in gitlab

            data = {'id': fork_id,

                    'name': 'c9s',

                    'allowed_to_push': [{'access_level': 40}],

                    'allowed_to_merge': [{'access_level': 40}],

                    }

            rv = requests.post('{0}/projects/{1}/protected_branches'.format(api_url, fork_id), json=data, headers=headers)

        except ConnectionError as error:

            error_msg = ('The connection to API failed while trying to reprotect c9s branch'

                         'in the fork fork. The error was: {0}'.format(str(error)))

            raise rpkgError(error_msg)

    base_error_msg = ('The following error occurred while creating a new fork: {0}')

    if not rv.ok:

        # fork was already created

        if rv.status_code == 409 or rv.reason == "Conflict":

            # When the repo already exists, the return doesn't contain the repo

            # path or username.  Make one more API call to get the username of

            # the token to construct the repo path.

            rv = requests.get('{0}/user'.format(api_url), headers=headers)

            username = rv.json()['username']

            return False, '{0}/{1}'.format(username, safe_name)

        # show hint for invalid, expired or revoked token

        elif rv.status_code == 401 or rv.reason == "Unauthorized":

            base_error_msg += '\nFor invalid or expired token refer to ' \

                '"{0} fork -h" to set a token in your user ' \

                'configuration.'.format(cli_name)

        raise rpkgError(base_error_msg.format(rv.text))

    return True, rv_json['path_with_namespace']

def do_add_remote(base_url, remote_base_url, repo, repo_path, remote_name):

    """

    Adds remote tracked repository

    :param base_url: a string of the URL repository

    :param remote_base_url: a string of the remote tracked repository

    :param repo: object, current project git repository

    :param repo_path: a string of the repository path

    :param remote_name: a string of the remote name

    :return: a bool; True if remote was created, False when already exists

    """

    parsed_url = urlparse(remote_base_url)

    remote_url = '{0}://{1}/{2}.git'.format(

        parsed_url.scheme,

        parsed_url.netloc,

        repo_path,

    )

    # check already existing remote

    for remote in repo.remotes:

        if remote.name == remote_name:

            return False

    try:

        repo.create_remote(remote_name, url=remote_url)

    except git.exc.GitCommandError as e:

        error_msg = "During create remote:\n  {0}\n  {1}".format(

            " ".join(e.command), e.stderr)

        raise rpkgError(error_msg)

    return True

def get_names_from_specs(specdir=None):

    prev_cwd = Path.cwd()

    if specdir:

        os.chdir(specdir)

    try:

        return [f[:-5] for f in os.listdir() if f.endswith('.spec')]

    except ValueError as e:

        raise ValueError("Didn't find source file with name.")

    finally:

        os.chdir(prev_cwd)

def get_names_from_git(gitdir=None):

    prev_cwd = Path.cwd()

    return  list(Path(urlparse(u).path).with_suffix('').name

        for r in git.Repo(gitdir or Path.cwd()).remotes

        for u in r.urls if "redhat" in u)

def reset_git_origin(old_name, new_name, gitdir=None):

    for r in git.Repo(gitdir or Path.cwd()).remotes:

        if r.name == 'origin':

            current_url = r.url

            new_url = current_url.replace(old_name, new_name)

            r.set_url(new_url)

def parse_project_dir(repo):

    return Path(repo).with_suffix('').name

def fix_repo(project_dir=None):

    path = Path(project_dir) if project_dir else Path.cwd()

    spec_name, git_name, dir_name = get_project_names(path)

    if spec_name != git_name:

        #self.log.info("Changing the git-remote {} to match {}".format(git_name, spec_name))

        reset_git_origin(git_name,spec_name,path)

    if spec_name != dir_name:

        #self.log.info("Changing the directory {} to match the specfile {}.spec".format(dir_name, spec_name))

        os.rename(path,path.parent / spec_name)

def get_project_names(projectdir=None):

    cwd = Path(projectdir) if projectdir else Path.cwd()

    spec_names = get_names_from_specs(cwd)

    git_names = get_names_from_git(cwd)

    dir_name = cwd.name

    lcase_names = set(s.lower() for s in spec_names).intersection(set(s.lower() for s in git_names))

    try:

        [spec_name] = [s for s in spec_names if s.lower() in lcase_names]

        [git_name,*_] = [s for s in git_names if s.lower() in lcase_names]

        return spec_name, git_name, dir_name

    except ValueError as e:

        raise ValueError("Instead of a single project name found {}".format(spec_names))

def config_get_safely(config, section, option):

    """

    Returns option from the user's configuration file. In case of missing

    section or option method throws an exception with a human-readable

    warning and a possible hint.

    The method should be used especially in situations when there are newly

    added sections/options into the config. In this case, there is a risk that

    the user's config wasn't properly upgraded.

    :param config: ConfigParser object

    :param section: section name in the config

    :param option: name of the option

    :return: option value from the right section

    :rtype: str

    """

    hint = (

        "First (if possible), refer to the help of the current command "

        "(-h/--help).\n"

        "There also might be a new version of the config after upgrade.\n"

        "Hint: you can check if you have 'centpkg.conf.rpmnew' or "

        "'centpkg.conf.rpmsave' in the config directory. If yes, try to merge "

        "your changes to the config with the maintainer provided version "

        "(or replace centpkg.conf file with 'centpkg.conf.rpmnew')."

    )

    try:

        return config.get(section, option)

    except NoSectionError:

        msg = "Missing section '{0}' in the config file.".format(section)

        raise rpkgError("{0}\n{1}".format(msg, hint))

    except NoOptionError:

        msg = "Missing option '{0}' in the section '{1}' of the config file.".format(

            option, section

        )

        raise rpkgError("{0}\n{1}".format(msg, hint))

    except Exception:

        raise

def get_canonical_repo_name(config, repo_url):

    """

    Check whether the current repo is a fork and if so, retrieve the parent

    fork to get the proper name.

    """

    # Look up the repo and query for forked_from_project

    cli_name = config_get_safely(dist_git_config, '__default', 'cli_name')

    distgit_section = '{0}.distgit'.format(cli_name)

    distgit_api_base_url = config_get_safely(dist_git_config, distgit_section, "apibaseurl")

    # Make sure the fork comes from the same Gitlab instance

    parsed_repo_url = urlparse(repo_url)

    parsed_base_url = urlparse(distgit_api_base_url)

    try:

        distgit_token = config_get_safely(dist_git_config, distgit_section, 'token')

        api_url = '{0}/api/v4'.format(distgit_api_base_url.rstrip('/'))

        project_url = '{0}/projects/{1}'.format(api_url, quote_plus(parsed_repo_url.path.lstrip('/')))

        headers = {

            'PRIVATE-TOKEN': distgit_token,

            'Accept': 'application/json',

            'Content-Type': 'application/json'

        }

        rv = requests.get(project_url, headers=headers)

        rv.raise_for_status()

        # Extract response json for debugging

        rv_json = rv.json()

        canonical_repo_name = rv_json['forked_from_project']['name']

    except KeyError as e:

        # There was no 'forked_from_project' key, likely meaning the

        # user lacked permissions to read the API. Usually this means

        # they haven't supplied a token or it is expired.

        raise rpkgError("Insufficient Gitlab API permissions. Missing token?")

    except Exception as e:

        # For any other exception, just fall back to using the last segment

        # of the URL path.

        canonical_repo_name = parsed_repo_url.path.split('/')[-1]

    # Chop off a trailing .git if any

    return canonical_repo_name.rsplit('.git', 1)[0]

def get_repo_name(name, org='rpms'):

    """

    Try to parse the repository name in case it is a git url.

    Parameters

    ----------

    name: str

        The repository name, including the org name.

        It will try to retrieve both  repository name and org in case "name" is an url.

    org: str

        The org to use in case name parsing is needed.

    Returns

    -------

    str

        A string containing the repository name: $ORG/$REPO`.

        It will return the original `name` parameter in case of regex match failure.

    """

    if name.startswith(org):

        return name

    # This is probably a renamed fork, so try to find the fork's parent

    repo_name = get_canonical_repo_name(dist_git_config, name)

    return '%s/%s' % (org, repo_name)