##########################################################################
#
# pgAdmin 4 - PostgreSQL Tools
#
# Copyright (C) 2013 - 2018, The pgAdmin Development Team
# This software is released under the PostgreSQL Licence
#
##########################################################################

"""Implements pgAdmin4 User Management Utility"""

import simplejson as json
import re

from flask import render_template, request, \
    url_for, Response, abort
from flask_babel import gettext as _
from flask_security import login_required, roles_required, current_user
from flask_security.utils import encrypt_password

import config
from pgadmin.utils import PgAdminModule
from pgadmin.utils.ajax import make_response as ajax_response, \
    make_json_response, bad_request, internal_server_error

from pgadmin.model import db, Role, User, UserPreference, Server, \
    ServerGroup, Process, Setting

# set template path for sql scripts
MODULE_NAME = 'user_management'
server_info = {}


class UserManagementModule(PgAdminModule):
    """
    class UserManagementModule(Object):

        It is a utility which inherits PgAdminModule
        class and define methods to load its own
        javascript file.
    """

    LABEL = _('Users')

    def get_own_javascripts(self):
        """"
        Returns:
            list: js files used by this module
        """
        return [{
            'name': 'pgadmin.tools.user_management',
            'path': url_for('user_management.index') + 'user_management',
            'when': None
        },{
            'name': 'pgadmin.user_management.current_user',
            'path': url_for('user_management.index') + 'current_user',
            'when': None,
            'is_template': True
        }]

    def show_system_objects(self):
        """
        return system preference objects
        """
        return self.pref_show_system_objects

    def get_exposed_url_endpoints(self):
        """
        Returns:
            list: URL endpoints for backup module
        """
        return [
            'user_management.roles', 'user_management.role',
            'user_management.update_user', 'user_management.delete_user',
            'user_management.create_user', 'user_management.users',
            'user_management.user'
        ]


# Create blueprint for BackupModule class
blueprint = UserManagementModule(
    MODULE_NAME, __name__, static_url_path=''
)


def validate_user(data):
    new_data = dict()
    email_filter = re.compile("^[a-zA-Z0-9.!#$%&'*+\/=?^_`{|}~-]+@[a-zA-Z0-9]"
                              "(?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9]"
                              "(?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$")

    if ('newPassword' in data and data['newPassword'] != "" and
                'confirmPassword' in data and data['confirmPassword'] != ""):

        if data['newPassword'] == data['confirmPassword']:
            new_data['password'] = encrypt_password(data['newPassword'])
        else:
            raise Exception(_("Passwords do not match."))

    if 'email' in data and data['email'] != "":
        if email_filter.match(data['email']):
            new_data['email'] = data['email']
        else:
            raise Exception(_("Invalid email address."))

    if 'role' in data and data['role'] != "":
        new_data['roles'] = int(data['role'])

    if 'active' in data and data['active'] != "":
        new_data['active'] = data['active']

    return new_data


@blueprint.route("/")
@login_required
def index():
    return bad_request(errormsg=_("This URL cannot be called directly."))


@blueprint.route("/user_management.js")
@login_required
def script():
    """render own javascript"""
    return Response(
        response=render_template(
            "user_management/js/user_management.js", _=_,
            is_admin=current_user.has_role("Administrator"),
            user_id=current_user.id
        ),
        status=200,
        mimetype="application/javascript"
    )

@blueprint.route("/current_user.js")
@login_required
def current_user_info():
    return Response(
        response=render_template(
            "user_management/js/current_user.js",
            is_admin='true' if current_user.has_role("Administrator") else 'false',
            user_id=current_user.id,
            email=current_user.email,
            name=(
                current_user.email.split('@')[0] if config.SERVER_MODE is True
                else 'postgres'
            ),
            allow_save_password='true' if config.ALLOW_SAVE_PASSWORD else 'false'
        ),
        status=200,
        mimetype="application/javascript"
    )


@blueprint.route(
    '/user/', methods=['GET'], defaults={'uid': None}, endpoint='users'
)
@blueprint.route('/user/<int:uid>', methods=['GET'], endpoint='user')
@roles_required('Administrator')
def user(uid):
    """

    Args:
      uid: User id

    Returns: List of pgAdmin4 users or single user if uid is provided.

    """

    if uid:
        u = User.query.get(uid)

        res = {'id': u.id,
               'email': u.email,
               'active': u.active,
               'role': u.roles[0].id
               }
    else:
        users = User.query.all()

        users_data = []
        for u in users:
            users_data.append({'id': u.id,
                               'email': u.email,
                               'active': u.active,
                               'role': u.roles[0].id
                               })

        res = users_data

    return ajax_response(
        response=res,
        status=200
    )


@blueprint.route('/user/', methods=['POST'], endpoint='create_user')
@roles_required('Administrator')
def create():
    """

    Returns:

    """
    data = request.form if request.form else json.loads(
        request.data, encoding='utf-8'
    )

    for f in ('email', 'role', 'active', 'newPassword', 'confirmPassword'):
        if f in data and data[f] != '':
            continue
        else:
            return bad_request(errormsg=_("Missing field: '{0}'".format(f)))

    try:
        new_data = validate_user(data)

        if 'roles' in new_data:
            new_data['roles'] = [Role.query.get(new_data['roles'])]

    except Exception as e:
        return bad_request(errormsg=_(str(e)))

    try:
        usr = User(email=new_data['email'],
                   roles=new_data['roles'],
                   active=new_data['active'],
                   password=new_data['password'])
        db.session.add(usr)
        db.session.commit()
        # Add default server group for new user.
        server_group = ServerGroup(user_id=usr.id, name="Servers")
        db.session.add(server_group)
        db.session.commit()
    except Exception as e:
        return internal_server_error(errormsg=str(e))

    res = {'id': usr.id,
           'email': usr.email,
           'active': usr.active,
           'role': usr.roles[0].id
           }

    return ajax_response(
        response=res,
        status=200
    )


@blueprint.route('/user/<int:uid>', methods=['DELETE'], endpoint='delete_user')
@roles_required('Administrator')
def delete(uid):
    """

    Args:
      uid:

    Returns:

    """
    usr = User.query.get(uid)

    if not usr:
        abort(404)

    try:

        Setting.query.filter_by(user_id=uid).delete()

        UserPreference.query.filter_by(uid=uid).delete()

        Server.query.filter_by(user_id=uid).delete()

        ServerGroup.query.filter_by(user_id=uid).delete()

        Process.query.filter_by(user_id=uid).delete()

        # Finally delete user
        db.session.delete(usr)

        db.session.commit()

        return make_json_response(
            success=1,
            info=_("User deleted."),
            data={}
        )
    except Exception as e:
        return internal_server_error(errormsg=str(e))


@blueprint.route('/user/<int:uid>', methods=['PUT'], endpoint='update_user')
@roles_required('Administrator')
def update(uid):
    """

    Args:
      uid:

    Returns:

    """

    usr = User.query.get(uid)

    if not usr:
        abort(404)

    data = request.form if request.form else json.loads(
        request.data, encoding='utf-8'
    )

    try:
        new_data = validate_user(data)

        if 'roles' in new_data:
            new_data['roles'] = [Role.query.get(new_data['roles'])]

    except Exception as e:
        return bad_request(errormsg=_(str(e)))

    try:
        for k, v in new_data.items():
            setattr(usr, k, v)

        db.session.commit()

        res = {'id': usr.id,
               'email': usr.email,
               'active': usr.active,
               'role': usr.roles[0].id
               }

        return ajax_response(
            response=res,
            status=200
        )

    except Exception as e:
        return internal_server_error(errormsg=str(e))


@blueprint.route(
    '/role/', methods=['GET'], defaults={'rid': None}, endpoint='roles'
)
@blueprint.route('/role/<int:rid>', methods=['GET'], endpoint='role')
@roles_required('Administrator')
def role(rid):
    """

    Args:
      rid: Role id

    Returns: List of pgAdmin4 users roles or single role if rid is provided.

    """

    if rid:
        r = Role.query.get(rid)

        res = {'id': r.id, 'name': r.name}
    else:
        roles = Role.query.all()

        roles_data = []
        for r in roles:
            roles_data.append({'id': r.id,
                               'name': r.name})

        res = roles_data

    return ajax_response(
        response=res,
        status=200
    )