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

"""

 (c) 2016 - Copyright Red Hat Inc

 Authors:

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

"""

from __future__ import unicode_literals, absolute_import

import sqlalchemy as sa

import wtforms

try:

    from flask_wtf import FlaskForm

except ImportError:

    from flask_wtf import Form as FlaskForm

from sqlalchemy.orm import relation

from sqlalchemy.orm import backref

import pagure.lib.git

from pagure.hooks import BaseHook, BaseRunner, RequiredIf

from pagure.lib.model import BASE, Project

class PagureForceCommitTable(BASE):

    """ Stores information about the pagure hook deployed on a project.

    Table -- hook_pagure_force_commit

    """

    __tablename__ = "hook_pagure_force_commit"

    id = sa.Column(sa.Integer, primary_key=True)

    project_id = sa.Column(

        sa.Integer,

        sa.ForeignKey("projects.id", onupdate="CASCADE", ondelete="CASCADE"),

        nullable=False,

        unique=True,

        index=True,

    )

    branches = sa.Column(sa.Text, nullable=False)

    active = sa.Column(sa.Boolean, nullable=False, default=False)

    project = relation(

        "Project",

        foreign_keys=[project_id],

        remote_side=[Project.id],

        backref=backref(

            "pagure_force_commit_hook",

            cascade="delete, delete-orphan",

            single_parent=True,

            uselist=False,

        ),

    )

class PagureForceCommitRunner(BaseRunner):

    """ Runner for the hook blocking force push. """

    @staticmethod

    def pre_receive(session, username, project, repotype, repodir, changes):

        """ Run the pre-receive tasks of a hook.

        For args, see BaseRunner.runhook.

        """

        # Get the list of branches

        branches = []

        if project.pagure_force_commit_hook:

            branches = [

                branch.strip()

                for branch in project.pagure_force_commit_hook.branches.split(

                    ","

                )

                if branch.strip()

            ]

        for refname in changes:

            (oldrev, newrev) = changes[refname]

            refname = refname.replace("refs/heads/", "")

            if refname in branches or branches == ["*"]:

                if set(newrev) == set(["0"]):

                    raise Exception("Deletion is forbidden")

                elif pagure.lib.git.is_forced_push(oldrev, newrev, repodir):

                    raise Exception("Non fast-forward push is forbidden")

class PagureForceCommitForm(FlaskForm):

    """ Form to configure the pagure hook. """

    branches = wtforms.StringField("Branches", [RequiredIf("active")])

    active = wtforms.BooleanField("Active", [wtforms.validators.Optional()])

class PagureForceCommitHook(BaseHook):

    """ PagurPagureForceCommit hook. """

    name = "Block non fast-forward pushes"

    description = (

        "Using this hook you can block any non-fast-forward "

        "commit forced pushed to one or more branches.\n"

        "You can specify one or more branch names (sperated them using "

        "commas) or block all the branches by specifying: ``*``"

    )

    form = PagureForceCommitForm

    db_object = PagureForceCommitTable

    backref = "pagure_force_commit_hook"

    form_fields = ["branches", "active"]

    hook_type = "pre-receive"

    runner = PagureForceCommitRunner