/*
 * Copyright (C) 2016 ScyllaDB
 */

/*
 * This file is part of Scylla.
 *
 * Scylla is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Scylla is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Scylla.  If not, see <http://www.gnu.org/licenses/>.
 */


#include <boost/range/irange.hpp>
#include <boost/range/adaptors.hpp>
#include <boost/range/algorithm.hpp>
#include <boost/test/unit_test.hpp>
#include <stdint.h>

#include <seastar/core/future-util.hh>
#include <seastar/core/shared_ptr.hh>
#include <seastar/core/thread.hh>

#include "tests/test-utils.hh"
#include "tests/cql_test_env.hh"
#include "tests/cql_assertions.hh"

#include "auth/auth.hh"
#include "auth/data_resource.hh"
#include "auth/authenticator.hh"
#include "auth/password_authenticator.hh"
#include "auth/authenticated_user.hh"

#include "db/config.hh"
#include "cql3/query_processor.hh"

#include "disk-error-handler.hh"

thread_local disk_error_signal_type commit_error;
thread_local disk_error_signal_type general_disk_error;

SEASTAR_TEST_CASE(test_data_resource) {
    auth::data_resource root, keyspace("fisk"), column_family("fisk", "notter");

    BOOST_REQUIRE_EQUAL(root.is_root_level(), true);
    BOOST_REQUIRE_EQUAL(keyspace.is_keyspace_level(), true);
    BOOST_REQUIRE_EQUAL(column_family.is_column_family_level(), true);

    BOOST_REQUIRE_EQUAL(root.has_parent(), false);
    BOOST_REQUIRE_EQUAL(keyspace.has_parent(), true);
    BOOST_REQUIRE_EQUAL(column_family.has_parent(), true);

    try {
        root.get_parent();
        BOOST_FAIL("Should not reach");
    } catch (...) {
        //  ok
    }

    BOOST_REQUIRE_EQUAL(keyspace.get_parent(), root);
    BOOST_REQUIRE_EQUAL(column_family.get_parent(), keyspace);

    return make_ready_future();
}

SEASTAR_TEST_CASE(test_default_authenticator) {
    return do_with_cql_env([](cql_test_env&) {
        BOOST_REQUIRE_EQUAL(auth::authenticator::get().require_authentication(), false);
        BOOST_REQUIRE_EQUAL(auth::authenticator::get().class_name(), auth::authenticator::ALLOW_ALL_AUTHENTICATOR_NAME);
        return make_ready_future();
    });
}

SEASTAR_TEST_CASE(test_password_authenticator_attributes) {
    db::config cfg;
    cfg.authenticator = auth::password_authenticator::PASSWORD_AUTHENTICATOR_NAME;

    return do_with_cql_env([](cql_test_env&) {
        BOOST_REQUIRE_EQUAL(auth::authenticator::get().require_authentication(), true);
        BOOST_REQUIRE_EQUAL(auth::authenticator::get().class_name(), auth::password_authenticator::PASSWORD_AUTHENTICATOR_NAME);
        return make_ready_future();
    }, cfg);
}

SEASTAR_TEST_CASE(test_auth_users) {
    db::config cfg;
    cfg.authenticator = auth::password_authenticator::PASSWORD_AUTHENTICATOR_NAME;

    return do_with_cql_env([](cql_test_env&) {
        return seastar::async([] {
            sstring username("fisk");
            auth::auth::insert_user(username, false).get();
            BOOST_REQUIRE_EQUAL(auth::auth::is_existing_user(username).get0(), true);
            BOOST_REQUIRE_EQUAL(auth::auth::is_super_user(username).get0(), false);

            auth::auth::insert_user(username, true).get();
            BOOST_REQUIRE_EQUAL(auth::auth::is_existing_user(username).get0(), true);
            BOOST_REQUIRE_EQUAL(auth::auth::is_super_user(username).get0(), true);

            auth::auth::delete_user(username).get();
            BOOST_REQUIRE_EQUAL(auth::auth::is_existing_user(username).get0(), false);
            BOOST_REQUIRE_EQUAL(auth::auth::is_super_user(username).get0(), false);
        });
    }, cfg);
}

SEASTAR_TEST_CASE(test_password_authenticator_operations) {
    db::config cfg;
    cfg.authenticator = auth::password_authenticator::PASSWORD_AUTHENTICATOR_NAME;

    /**
     * Not using seastar::async due to apparent ASan bug.
     * Enjoy the slightly less readable code.
     */
    return do_with_cql_env([](cql_test_env&) {
        sstring username("fisk");
        sstring password("notter");

        using namespace auth;
        using option = authenticator::option;
        using user_ptr = ::shared_ptr<authenticated_user>;

        auto USERNAME_KEY = authenticator::USERNAME_KEY;
        auto PASSWORD_KEY = authenticator::PASSWORD_KEY;


        // check non-existing user
        return authenticator::get().authenticate({ { USERNAME_KEY, username }, { PASSWORD_KEY, password } }).then_wrapped([](future<user_ptr>&& f) {
            try {
                f.get();
                BOOST_FAIL("should not reach");
            } catch (exceptions::authentication_exception&) {
                // ok
            }
        }).then([=] {
            return authenticator::get().create(username, { { option::PASSWORD, password} }).then([=] {
                return authenticator::get().authenticate({ { USERNAME_KEY, username }, { PASSWORD_KEY, password } }).then([=](user_ptr user) {
                    BOOST_REQUIRE_EQUAL(user->name(), username);
                    BOOST_REQUIRE_EQUAL(user->is_anonymous(), false);
                });
            });
        }).then([=] {
            // check wrong password
            return authenticator::get().authenticate( { {USERNAME_KEY, username}, {PASSWORD_KEY, "hejkotte"}}).then_wrapped([](future<user_ptr>&& f) {
                try {
                    f.get();
                    BOOST_FAIL("should not reach");
                } catch (exceptions::authentication_exception&) {
                    // ok
                }
            });
        }).then([=] {
            // sasl
            auto sasl = authenticator::get().new_sasl_challenge();

            BOOST_REQUIRE_EQUAL(sasl->is_complete(), false);

            bytes b;
            int8_t i = 0;
            b.append(&i, 1);
            b.insert(b.end(), username.begin(), username.end());
            b.append(&i, 1);
            b.insert(b.end(), password.begin(), password.end());

            sasl->evaluate_response(b);
            BOOST_REQUIRE_EQUAL(sasl->is_complete(), true);

            return sasl->get_authenticated_user().then([=](user_ptr user) {
                BOOST_REQUIRE_EQUAL(user->name(), username);
                BOOST_REQUIRE_EQUAL(user->is_anonymous(), false);
            });
        }).then([=] {
            // check deleted user
            return authenticator::get().drop(username).then([=] {
                return authenticator::get().authenticate({ { USERNAME_KEY, username }, { PASSWORD_KEY, password } }).then_wrapped([](future<user_ptr>&& f) {
                    try {
                        f.get();
                        BOOST_FAIL("should not reach");
                    } catch (exceptions::authentication_exception&) {
                        // ok
                    }
                });
            });
        });
    }, cfg);
}


SEASTAR_TEST_CASE(test_cassandra_hash) {
    db::config cfg;
    cfg.authenticator = auth::password_authenticator::PASSWORD_AUTHENTICATOR_NAME;

    return do_with_cql_env([](cql_test_env& env) {
        /**
         * Try to check password against hash from origin.
         * Allow for specific failure if glibc cannot handle the
         * hash algo (i.e. blowfish).
         */

        sstring username("fisk");
        sstring password("cassandra");
        sstring salted_hash("$2a$10$8cz4EZ5v8f/aTZFkNEQafe.z66ZvjOonOpHCApwx0ksWp3aKf.Roq");

        // This is extremely whitebox. We'll just go right ahead and know
        // what the tables etc are called. Oy wei...
        auto f = env.local_qp().process("INSERT into system_auth.credentials (username, salted_hash) values (?, ?)", db::consistency_level::ONE,
                        { username, salted_hash }).discard_result();

        return f.then([=] {
            auto& a = auth::authenticator::get();

            auto USERNAME_KEY = auth::authenticator::USERNAME_KEY;
            auto PASSWORD_KEY = auth::authenticator::PASSWORD_KEY;
            using user_ptr = ::shared_ptr<auth::authenticated_user>;

            // try to verify our user with a cassandra-originated salted_hash
            return a.authenticate({ { USERNAME_KEY, username }, { PASSWORD_KEY, password } }).then_wrapped([](future<user_ptr> f) {
                try {
                    f.get();
                } catch (exceptions::authentication_exception& e) {
                    try {
                        std::rethrow_if_nested(e);
                        BOOST_FAIL(std::string("Unexcepted exception ") + e.what());
                    } catch (std::system_error & e) {
                        bool is_einval = e.code().category() == std::system_category() && e.code().value() == EINVAL;
                        BOOST_WARN_MESSAGE(is_einval, "Could not verify cassandra password hash due to glibc limitation");
                        if (!is_einval) {
                            BOOST_FAIL(std::string("Unexcepted system error ") + e.what());
                        }
                    }
                }
            });
        });
    }, cfg);
}