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

"""

 (c) 2014 - Copyright Red Hat Inc

 Authors:

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

"""

import os

import sqlalchemy

from datetime import timedelta

from sqlalchemy.orm import sessionmaker

from sqlalchemy.orm import scoped_session

from sqlalchemy.orm.exc import NoResultFound

from sqlalchemy.exc import SQLAlchemyError

import pygit2

import progit.exceptions

from progit import model

def create_session(db_url, debug=False, pool_recycle=3600):

    ''' Create the Session object to use to query the database.

    :arg db_url: URL used to connect to the database. The URL contains

    information with regards to the database engine, the host to connect

    to, the user and password and the database name.

      ie: <engine>://<user>:<password>@<host>/<dbname></dbname></host></password></user></engine>

    :kwarg debug: a boolean specifying wether we should have the verbose

        output of sqlalchemy or not.

    :return a Session that can be used to query the database.

    '''

    engine = sqlalchemy.create_engine(

        db_url, echo=debug, pool_recycle=pool_recycle)

    scopedsession = scoped_session(sessionmaker(bind=engine))

    return scopedsession

def get_user(session, username):

    ''' Return the user corresponding to this username, or None. '''

    user = session.query(

        model.User

    ).filter(

        model.User.user == username

    ).first()

    return user

def add_issue_comment(session, issue, comment, user):

    ''' Add a comment to an issue. '''

    user_obj = get_user(session, username)

    if not user_obj:

        raise progit.exceptions.ProgitException(

            'No user "%s" found' % user

        )

    isse_comment = model.IssueComment(

        issue_id=issue.id,

        comment=comment,

        user_id=user_obj.id,

    )

    session.add(isse_comment)

    # Make sure we won't have SQLAlchemy error before we create the repo

    session.flush()

    return 'Comment added'

def get_user_project(session, username):

    ''' Retrieve the list of projects managed by a user.

    '''

    query = session.query(

        model.Project

    ).filter(

        model.Project.user == username

    )

    return query.all()

def new_project(session, user, name, gitfolder, docfolder,

                description=None, parent_id=None):

    ''' Create a new project based on the information provided.

    '''

    gitrepo = os.path.join(gitfolder, '%s.git' % name)

    if os.path.exists(gitrepo):

        raise progit.exceptions.RepoExistsException(

            'The project "%s" already exists' % name

        )

    user_obj = get_user(session, username)

    if not user_obj:

        raise progit.exceptions.ProgitException(

            'No user "%s" found' % user

        )

    project = model.Project(

        name=name,

        description=description,

        user_id=user_obj.id,

        parent_id=parent_id

    )

    session.add(project)

    # Make sure we won't have SQLAlchemy error before we create the repo

    session.flush()

    pygit2.init_repository(gitrepo, bare=True)

    gitrepo = os.path.join(docfolder, project.path)

    if os.path.exists(gitrepo):

        raise progit.exceptions.RepoExistsException(

            'The docs "%s" already exists' % project.path

        )

    pygit2.init_repository(gitrepo, bare=True)

    return 'Project "%s" created' % name

def new_issue(session, repo, title, content, user):

    ''' Create a new issue for the specified repo. '''

    user_obj = get_user(session, username)

    if not user_obj:

        raise progit.exceptions.ProgitException(

            'No user "%s" found' % user

        )

    issue = model.Issue(

        project_id=repo.id,

        title=title,

        content=content,

        user_id=user_obj.id,

    )

    session.add(issue)

    # Make sure we won't have SQLAlchemy error before we create the issue

    session.flush()

    return 'Issue created'

def new_pull_request(

        session, repo, repo_from, title, user, stop_id, start_id=None):

    ''' Create a new pull request on the specified repo. '''

    user_obj = get_user(session, username)

    if not user_obj:

        raise progit.exceptions.ProgitException(

            'No user "%s" found' % user

        )

    request = model.PullRequest(

        project_id=repo.id,

        project_id_from=repo_from.id,

        title=title,

        start_id=start_id,

        stop_id=stop_id,

        user_id=user_obj.id,

    )

    session.add(request)

    # Make sure we won't have SQLAlchemy error before we create the request

    session.flush()

    return 'Request created'

def edit_issue(session, issue, title=None, content=None, status=None):

    ''' Edit the specified issue.

    '''

    edit = []

    if title and title != issue.title:

        issue.title = title

        edit.append('title')

    if content and content != issue.content:

        issue.content = content

        edit.append('content')

    if status and status != issue.status:

        issue.status = status

        edit.append('status')

    if not edit:

        return 'No changes to edit'

    else:

        session.add(issue)

        session.flush()

        return 'Edited successfully issue #%s' % issue.id

def update_project_settings(session, repo, issue_tracker, project_docs):

    ''' Update the settings of a project. '''

    update = []

    if issue_tracker != repo.issue_tracker:

        repo.issue_tracker = issue_tracker

        update.append('issue_tracker')

    if project_docs != repo.project_docs:

        repo.project_docs = project_docs

        update.append('project_docs')

    if not update:

        return 'No settings to change'

    else:

        session.add(repo)

        session.flush()

        return 'Edited successfully setting of repo: %s' % repo.fullname

def fork_project(session, user, repo, gitfolder, forkfolder, docfolder):

    ''' Fork a given project into the user's forks. '''

    reponame = os.path.join(gitfolder, repo.path)

    forkreponame = os.path.join(forkfolder, user, repo.path)

    if os.path.exists(forkreponame):

        raise progit.exceptions.RepoExistsException(

            'Repo "%s/%s" already exists' % (user, repo.name))

    user_obj = get_user(session, username)

    if not user_obj:

        raise progit.exceptions.ProgitException(

            'No user "%s" found' % user

        )

    project = model.Project(

        name=repo.name,

        description=repo.description,

        user_id=user_obj.id,

        parent_id=repo.id

    )

    session.add(project)

    # Make sure we won't have SQLAlchemy error before we create the repo

    session.flush()

    pygit2.clone_repository(reponame, forkreponame, bare=True)

    gitrepo = os.path.join(docfolder, project.path)

    if os.path.exists(gitrepo):

        raise progit.exceptions.RepoExistsException(

            'The docs "%s" already exists' % project.path

        )

    pygit2.init_repository(gitrepo, bare=True)

    return 'Repo "%s" cloned to "%s/%s"' % (repo.name, user, repo.name)

def list_projects(

        session, username=None, fork=None,

        start=None, limit=None, count=False):

    '''List existing projects

    '''

    projects = session.query(model.Project)

    if username is not None:

        projects = projects.filter(

            model.User.user == username

        ).filter(

            model.User.id == model.Project.user_id

        )

    if fork is not None:

        if fork is True:

            projects = projects.filter(

                model.Project.parent_id != None

            )

        elif fork is False:

            projects = projects.filter(

                model.Project.parent_id == None

            )

    if start is not None:

        projects = projects.offset(start)

    if limit is not None:

        projects = projects.limit(limit)

    if count:

        return projects.count()

    else:

        return projects.all()

def get_project(session, name, user=None):

    '''Get a project from the database

    '''

    query = session.query(

        model.Project

    ).filter(

        model.Project.name == name

    )

    if user is not None:

        query = query.filter(

            model.User.user == user

        ).filter(

            model.User.id == model.Project.user_id

        ).filter(

            model.Project.parent_id != None

        )

    else:

        query = query.filter(

            model.Project.parent_id == None

        )

    return query.first()

def get_issues(session, repo, status=None, closed=False):

    ''' Retrieve all the issues associated to a project

    Watch out that the closed argument is incompatible with the status

    argument. The closed argument will return all the issues whose status

    is not 'Open', otherwise it will return the issues having the specified

    status.

    '''

    query = session.query(

        model.Issue

    ).filter(

        model.Issue.project_id == repo.id

    )

    if status is not None and not closed:

        query = query.filter(

            model.Issue.status == status

        )

    if closed:

        query = query.filter(

            model.Issue.status != 'Open'

        )

    return query.all()

def get_issue(session, issueid):

    ''' Retrieve the specified issue

    '''

    query = session.query(

        model.Issue

    ).filter(

        model.Issue.id == issueid

    )

    return query.first()

def get_pull_requests(

        session, project_id=None, project_id_from=None, status=None):

    ''' Retrieve the specified issue

    '''

    query = session.query(

        model.PullRequest

    )

    if project_id:

        query = query.filter(

            model.PullRequest.project_id == project_id

        )

    if project_id_from:

        query = query.filter(

            model.PullRequest.project_id_from == project_id_from

        )

    if status is not None:

        query = query.filter(

            model.PullRequest.status == status

        )

    return query.all()

def get_pull_request(

        session, requestid, project_id=None, project_id_from=None):

    ''' Retrieve the specified issue

    '''

    query = session.query(

        model.PullRequest

    ).filter(

        model.PullRequest.id == requestid

    )

    if project_id:

        query = query.filter(

            model.PullRequest.project_id == project_id

        )

    if project_id_from:

        query = query.filter(

            model.PullRequest.project_id_from == project_id_from

        )

    return query.first()

def close_pull_request(session, request):

    ''' Close the provided pull-request.

    '''

    request.status = False

    session.add(request)

    session.flush()

def get_issue_statuses(session):

    ''' Return the complete list of status an issue can have.

    '''

    output = []

    statuses = session.query(model.StatusIssue).all()

    for status in statuses:

        output.append(status.status)

    return output

def generate_gitolite_acls(session, configfile):

    ''' Generate the configuration file for gitolite for all projects

    on the forge.

    '''

    config = []

    for project in session.query(model.Project).all():

        config.append('repo %s' % project.fullname)

        config.append('  RW+ = %s' % project.user)

        for user in project.users:

            if user != project.user:

                config.append('  RW+ = %s' % user)

        config.append('')

    with open(configfile, 'w') as stream:

        for row in config:

            stream.write(row + '\n')

def set_up_user(session, username, fullname, user_email):

    ''' Set up a new user into the database or update its information. '''

    user = get_user(session, username)

    if not user:

        user = model.User(

            user=username,

            fullname=fullname)

        session.add(user)

        session.flush()

    if user.fullname != fullname:

        user.fullname = fullname

        session.add(user)

        session.flush()

    if user_email not in user.emails:

        useremail = model.UserEmail(

            user_id=user.id,

            email=user_email)

        session.add(useremail)

        session.flush()

def update_user_ssh(session, user, ssh_key):

    ''' Set up a new user into the database or update its information. '''

    if isinstance(user, basestring):

        user = get_user(session, user)

    message = 'Nothing to update'

    if ssh_key != user.public_ssh_key:

        user.public_ssh_key = ssh_key

        session.add(user)

        session.flush()

        message = 'Public ssh key updated'

    return message