# 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.

#

# 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 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,

# USA.

""" Pagure-flavored Markdown

Author: Ralph Bean <rbean@redhat.com></rbean@redhat.com>

        Pierre-Yves Chibon <pingou@pingoured.fr></pingou@pingoured.fr>

"""

import re

import flask

import markdown.inlinepatterns

import markdown.util

import pagure

import pagure.lib

MENTION_RE = r'@(\w+)'

EXPLICIT_LINK_RE = r'(?

'(fork[s]?/)?'\  # See if there is a `forks/` at the start

'([a-zA-Z0-9_-]*?/)?'\ # See if we have a `user/`

'([a-zA-Z0-9_-]*?/)?'\  # See if we have a `namespace/`

'([a-zA-Z0-9_-]+)'\  # Get the last part `project`

'#(?P<id>[0-9]+)'  # Get the identifier `#<id>`</id></id>

IMPLICIT_ISSUE_RE = r'[^|\w](?

IMPLICIT_PR_RE = r'[^|\w](?

STRIKE_THROUGH_RE = r'~~(\w+)~~'

class MentionPattern(markdown.inlinepatterns.Pattern):

    """ @user pattern class. """

    def handleMatch(self, m):

        """ When the pattern matches, update the text. """

        name = markdown.util.AtomicString(m.group(2))

        text = ' @%s' % name

        user = pagure.lib.search_user(pagure.SESSION, username=name)

        if not user:

            return text

        element = markdown.util.etree.Element("a")

        base_url = pagure.APP.config['APP_URL']

        if base_url.endswith('/'):

            base_url = base_url[:-1]

        url = '%s/user/%s' % (base_url, user.username)

        element.set('href', url)

        element.text = text

        return element

class ExplicitLinkPattern(markdown.inlinepatterns.Pattern):

    """ Explicit link pattern. """

    def handleMatch(self, m):

        """ When the pattern matches, update the text. """

        is_fork = m.group(2)

        user = m.group(3)

        namespace = m.group(4)

        repo = m.group(5)

        idx = m.group(6)

        text = '%s#%s' % (repo, idx)

        if not is_fork and user:

            namespace = user

            user = None

        if namespace:

            namespace = namespace.rstrip('/')

            text = '%s/%s' % (namespace, text)

        if user:

            user = user.rstrip('/')

            text = '%s/%s' % (user.rstrip('/'), text)

        try:

            idx = int(idx)

        except:

            return text

        issue = _issue_exists(user, namespace, repo, idx)

        if issue:

            return _obj_anchor_tag(user, namespace, repo, issue, text)

        request = _pr_exists(user, namespace, repo, idx)

        if request:

            return _obj_anchor_tag(user, namespace, repo, request, text)

        return text

class ImplicitIssuePattern(markdown.inlinepatterns.Pattern):

    """ Implicit issue pattern. """

    def handleMatch(self, m):

        """ When the pattern matches, update the text. """

        idx = markdown.util.AtomicString(m.group(2))

        text = ' #%s' % idx

        try:

            idx = int(idx)

        except:

            return text

        try:

            root = flask.request.url_root

            url = flask.request.url

        except RuntimeError:

            return text

        repo = namespace = user = None

        if flask.request.args.get('user'):

            user = flask.request.args.get('user')

        if flask.request.args.get('namespace'):

            namespace = flask.request.args.get('namespace')

        if flask.request.args.get('repo'):

            repo = flask.request.args.get('repo')

        if not user and not repo:

            if 'fork/' in url:

                user, repo = url.split('fork/')[1].split('/', 2)[:2]

            else:

                repo = url.split(root)[1].split('/', 1)[0]

        issue = _issue_exists(user, namespace, repo, idx)

        if issue:

            return _obj_anchor_tag(user, namespace, repo, issue, text)

        request = _pr_exists(user, namespace, repo, idx)

        if request:

            return _obj_anchor_tag(user, namespace, repo, request, text)

        return text

class ImplicitPRPattern(markdown.inlinepatterns.Pattern):

    """ Implicit pull-request pattern. """

    def handleMatch(self, m):

        """ When the pattern matches, update the text. """

        idx = markdown.util.AtomicString(m.group(2))

        text = ' PR#%s' % idx

        try:

            idx = int(idx)

        except:

            return text

        try:

            root = flask.request.url_root

            url = flask.request.url

        except RuntimeError:

            return text

        repo = namespace = user = None

        if flask.request.args.get('user'):

            user = flask.request.args.get('user')

        if flask.request.args.get('namespace'):

            namespace = flask.request.args.get('namespace')

        if flask.request.args.get('repo'):

            repo = flask.request.args.get('repo')

        if not user and not repo:

            if 'fork/' in url:

                user, repo = url.split('fork/')[1].split('/', 2)[:2]

            else:

                repo = url.split(root)[1].split('/', 1)[0]

        issue = _issue_exists(user, namespace, repo, idx)

        if issue:

            return _obj_anchor_tag(user, namespace, repo, issue, text)

        request = _pr_exists(user, namespace, repo, idx)

        if request:

            return _obj_anchor_tag(user, namespace, repo, request, text)

        return text

class StrikeThroughPattern(markdown.inlinepatterns.Pattern):

    """ ~~striked~~ pattern class. """

    def handleMatch(self, m):

        """ When the pattern matches, update the text. """

        text = markdown.util.AtomicString(m.group(2))

        element = markdown.util.etree.Element("del")

        element.text = text

        return element

class PagureExtension(markdown.extensions.Extension):

    def extendMarkdown(self, md, md_globals):

        # First, make it so that bare links get automatically linkified.

        markdown.inlinepatterns.AUTOLINK_RE = '(%s)' % '|'.join([

            r'<(?:f|ht)tps?://[^>]*>',

            r'\b(?:f|ht)tps?://[^)<>\s]+[^.,)<>\s]',

        ])

        md.inlinePatterns['mention'] = MentionPattern(MENTION_RE)

        if pagure.APP.config.get('ENABLE_TICKETS', True):

            md.inlinePatterns['implicit_pr'] = \

                ImplicitPRPattern(IMPLICIT_PR_RE)

            md.inlinePatterns['explicit_fork_issue'] = \

                ExplicitLinkPattern(EXPLICIT_LINK_RE)

            md.inlinePatterns['implicit_issue'] = \

                ImplicitIssuePattern(IMPLICIT_ISSUE_RE)

        md.inlinePatterns['striked'] = StrikeThroughPattern(

            STRIKE_THROUGH_RE)

        md.registerExtension(self)

def makeExtension(*arg, **kwargs):

    return PagureExtension(**kwargs)

def _issue_exists(user, namespace, repo, idx):

    """ Utility method checking if a given issue exists. """

    repo_obj = pagure.lib.get_project(

        pagure.SESSION, name=repo, user=user, namespace=namespace)

    if not repo_obj:

        return False

    issue_obj = pagure.lib.search_issues(

        pagure.SESSION, repo=repo_obj, issueid=idx)

    if not issue_obj:

        return False

    return issue_obj

def _pr_exists(user, namespace, repo, idx):

    """ Utility method checking if a given PR exists. """

    repo_obj = pagure.lib.get_project(

        pagure.SESSION, name=repo, user=user, namespace=namespace)

    if not repo_obj:

        return False

    pr_obj = pagure.lib.search_pull_requests(

        pagure.SESSION, project_id=repo_obj.id, requestid=idx)

    if not pr_obj:

        return False

    return pr_obj

def _obj_anchor_tag(user, namespace, repo, obj, text):

    """ Utility method generating the link to an issue or a PR. """

    if obj.isa == 'issue':

        url = flask.url_for(

            'view_issue', username=user, namespace=namespace, repo=repo,

             issueid=obj.id)

    else:

        url = flask.url_for(

            'request_pull', username=user, namespace=namespace, repo=repo,

            requestid=obj.id)

    element = markdown.util.etree.Element("a")

    element.set('href', url)

    element.set('title', obj.title)

    element.text = text

    return element