# Copyright 2015, 2016 OpenMarket Ltd
# Copyright 2017 Vector Creations Ltd
# Copyright 2018 New Vector Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import logging

from pkg_resources import DistributionNotFound, VersionConflict, get_distribution

logger = logging.getLogger(__name__)


# REQUIREMENTS is a simple list of requirement specifiers[1], and must be
# installed. It is passed to setup() as install_requires in setup.py.
#
# CONDITIONAL_REQUIREMENTS is the optional dependencies, represented as a dict
# of lists. The dict key is the optional dependency name and can be passed to
# pip when installing. The list is a series of requirement specifiers[1] to be
# installed when that optional dependency requirement is specified. It is passed
# to setup() as extras_require in setup.py
#
# [1] https://pip.pypa.io/en/stable/reference/pip_install/#requirement-specifiers.

REQUIREMENTS = [
    "jsonschema>=2.5.1",
    "frozendict>=1",
    "unpaddedbase64>=1.1.0",
    "canonicaljson>=1.1.3",
    "signedjson>=1.0.0",
    "pynacl>=1.2.1",
    "service_identity>=16.0.0",
    "Twisted>=17.1.0",
    "treq>=15.1",
    # Twisted has required pyopenssl 16.0 since about Twisted 16.6.
    "pyopenssl>=16.0.0",
    "pyyaml>=3.11",
    "pyasn1>=0.1.9",
    "pyasn1-modules>=0.0.7",
    "daemonize>=2.3.1",
    "bcrypt>=3.1.0",
    "pillow>=3.1.2",
    "sortedcontainers>=1.4.4",
    "psutil>=2.0.0",
    "pymacaroons-pynacl>=0.9.3",
    "msgpack>=0.4.2",
    "phonenumbers>=8.2.0",
    "six>=1.10",
    # prometheus_client 0.4.0 changed the format of counter metrics
    # (cf https://github.com/matrix-org/synapse/issues/4001)
    "prometheus_client>=0.0.18,<0.6.0",
    # we use attr.s(slots), which arrived in 16.0.0
    "attrs>=16.0.0",
    "netaddr>=0.7.18",
]

CONDITIONAL_REQUIREMENTS = {
    "email.enable_notifs": ["Jinja2>=2.9", "bleach>=1.4.2"],
    "matrix-synapse-ldap3": ["matrix-synapse-ldap3>=0.1"],
    "postgres": ["psycopg2>=2.6"],

    # ConsentResource uses select_autoescape, which arrived in jinja 2.9
    "resources.consent": ["Jinja2>=2.9"],

    "saml2": ["pysaml2>=4.5.0"],
    "url_preview": ["lxml>=3.5.0"],
    "test": ["mock>=2.0"],
}


def list_requirements():
    deps = set(REQUIREMENTS)
    for opt in CONDITIONAL_REQUIREMENTS.values():
        deps = set(opt) | deps

    return list(deps)


class DependencyException(Exception):
    @property
    def message(self):
        return "\n".join([
            "Missing Requirements: %s" % (", ".join(self.dependencies),),
            "To install run:",
            "    pip install --upgrade --force %s" % (" ".join(self.dependencies),),
            "",
        ])

    @property
    def dependencies(self):
        for i in self.args[0]:
            yield '"' + i + '"'


def check_requirements(for_feature=None, _get_distribution=get_distribution):
    deps_needed = []
    errors = []

    if for_feature:
        reqs = CONDITIONAL_REQUIREMENTS[for_feature]
    else:
        reqs = REQUIREMENTS

    for dependency in reqs:
        try:
            _get_distribution(dependency)
        except VersionConflict as e:
            deps_needed.append(dependency)
            errors.append(
                "Needed %s, got %s==%s"
                % (dependency, e.dist.project_name, e.dist.version)
            )
        except DistributionNotFound:
            deps_needed.append(dependency)
            errors.append("Needed %s but it was not installed" % (dependency,))

    if not for_feature:
        # Check the optional dependencies are up to date. We allow them to not be
        # installed.
        OPTS = sum(CONDITIONAL_REQUIREMENTS.values(), [])

        for dependency in OPTS:
            try:
                _get_distribution(dependency)
            except VersionConflict:
                deps_needed.append(dependency)
                errors.append("Needed %s but it was not installed" % (dependency,))
            except DistributionNotFound:
                # If it's not found, we don't care
                pass

    if deps_needed:
        for e in errors:
            logging.error(e)

        raise DependencyException(deps_needed)


if __name__ == "__main__":
    import sys

    sys.stdout.writelines(req + "\n" for req in list_requirements())
