#-*- 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_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, folder,

                description=None, parent_id=None):

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

    '''

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

    if os.path.exists(gitrepo):

        raise progit.exceptions.RepoExistsException(

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

        )

    project = model.Project(

        name=name,

        description=description,

        user=user,

        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)

    return 'Project "%s" created' % name

def fork_project(session, user, repo, repo_folder, fork_folder):

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

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

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

    if os.path.exists(forkreponame):

        raise progit.exceptions.RepoExistsException(

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

    project = model.Project(

        name=repo.name,

        description=repo.description,

        user=user,

        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)

    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_by(

            user=username

        )

    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.Project.user == user

        ).filter(

            model.Project.parent_id != None

        )

    else:

        query = query.filter(

            model.Project.parent_id == None

        )

    return query.first()