/*
Copyright 2022 The Matrix.org Foundation C.I.C.

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 EventEmitter from "events";
import { MethodLikeKeys, mocked, MockedObject, PropertyLikeKeys } from "jest-mock";
import { Feature, ServerSupport } from "matrix-js-sdk/src/feature";
import { MatrixClient, User } from "matrix-js-sdk/src/matrix";

import { MatrixClientPeg } from "../../src/MatrixClientPeg";

/**
 * Mocked generic class with a real EventEmitter.
 * Useful for mocks which need event emitters.
 */
export class MockEventEmitter<T> extends EventEmitter {
    /**
     * Construct a new event emitter with additional properties/functions. The event emitter functions
     * like .emit and .on will be real.
     * @param mockProperties An object with the mock property or function implementations. 'getters'
     * are correctly cloned to this event emitter.
     */
    constructor(mockProperties: Partial<Record<MethodLikeKeys<T> | PropertyLikeKeys<T>, unknown>> = {}) {
        super();
        // We must use defineProperties and not assign as the former clones getters correctly,
        // whereas the latter invokes the getter and sets the return value permanently on the
        // destination object.
        Object.defineProperties(this, Object.getOwnPropertyDescriptors(mockProperties));
    }
}

/**
 * Mock client with real event emitter
 * useful for testing code that listens
 * to MatrixClient events
 */
export class MockClientWithEventEmitter extends EventEmitter {
    constructor(mockProperties: Partial<Record<MethodLikeKeys<MatrixClient>, unknown>> = {}) {
        super();

        Object.assign(this, mockProperties);
    }
}

/**
 * - make a mock client
 * - cast the type to mocked(MatrixClient)
 * - spy on MatrixClientPeg.get to return the mock
 * eg
 * ```
 * const mockClient = getMockClientWithEventEmitter({
        getUserId: jest.fn().mockReturnValue(aliceId),
    });
 * ```
 *
 * See also {@link stubClient} which does something similar but uses a more complete mock client.
 */
export const getMockClientWithEventEmitter = (
    mockProperties: Partial<Record<keyof MatrixClient, unknown>>,
): MockedObject<MatrixClient> => {
    const mock = mocked(new MockClientWithEventEmitter(mockProperties) as unknown as MatrixClient);

    jest.spyOn(MatrixClientPeg, "get").mockReturnValue(mock);
    jest.spyOn(MatrixClientPeg, "safeGet").mockReturnValue(mock);

    // @ts-ignore simplified test stub
    mock.canSupport = new Map();
    Object.keys(Feature).forEach((feature) => {
        mock.canSupport.set(feature as Feature, ServerSupport.Stable);
    });
    return mock;
};

export const unmockClientPeg = () => {
    jest.spyOn(MatrixClientPeg, "get").mockRestore();
    jest.spyOn(MatrixClientPeg, "safeGet").mockRestore();
};

/**
 * Returns basic mocked client methods related to the current user
 * ```
 * const mockClient = getMockClientWithEventEmitter({
        ...mockClientMethodsUser('@mytestuser:domain'),
    });
 * ```
 */
export const mockClientMethodsUser = (userId = "@alice:domain") => ({
    getUserId: jest.fn().mockReturnValue(userId),
    getSafeUserId: jest.fn().mockReturnValue(userId),
    getUser: jest.fn().mockReturnValue(new User(userId)),
    isGuest: jest.fn().mockReturnValue(false),
    mxcUrlToHttp: jest.fn().mockReturnValue("mock-mxcUrlToHttp"),
    credentials: { userId },
    getThreePids: jest.fn().mockResolvedValue({ threepids: [] }),
    getAccessToken: jest.fn(),
    getDeviceId: jest.fn(),
    getAccountData: jest.fn(),
});

/**
 * Returns basic mocked client methods related to rendering events
 * ```
 * const mockClient = getMockClientWithEventEmitter({
        ...mockClientMethodsUser('@mytestuser:domain'),
    });
 * ```
 */
export const mockClientMethodsEvents = () => ({
    decryptEventIfNeeded: jest.fn(),
    getPushActionsForEvent: jest.fn(),
});

/**
 * Returns basic mocked client methods related to server support
 */
export const mockClientMethodsServer = (): Partial<Record<MethodLikeKeys<MatrixClient>, unknown>> => ({
    getIdentityServerUrl: jest.fn(),
    getHomeserverUrl: jest.fn(),
    getCapabilities: jest.fn().mockReturnValue({}),
    getClientWellKnown: jest.fn().mockReturnValue({}),
    doesServerSupportUnstableFeature: jest.fn().mockResolvedValue(false),
    isVersionSupported: jest.fn().mockResolvedValue(false),
    getVersions: jest.fn().mockResolvedValue({}),
    isFallbackICEServerAllowed: jest.fn(),
});

export const mockClientMethodsDevice = (
    deviceId = "test-device-id",
): Partial<Record<MethodLikeKeys<MatrixClient>, unknown>> => ({
    getDeviceId: jest.fn().mockReturnValue(deviceId),
    getDeviceEd25519Key: jest.fn(),
    getDevices: jest.fn().mockResolvedValue({ devices: [] }),
});

export const mockClientMethodsCrypto = (): Partial<
    Record<MethodLikeKeys<MatrixClient> & PropertyLikeKeys<MatrixClient>, unknown>
> => ({
    isCryptoEnabled: jest.fn(),
    isCrossSigningReady: jest.fn(),
    isKeyBackupKeyStored: jest.fn(),
    getCrossSigningCacheCallbacks: jest.fn().mockReturnValue({ getCrossSigningKeyCache: jest.fn() }),
    getStoredCrossSigningForUser: jest.fn(),
    getKeyBackupVersion: jest.fn().mockResolvedValue(null),
    secretStorage: { hasKey: jest.fn() },
    getCrypto: jest.fn().mockReturnValue({
        getUserDeviceInfo: jest.fn(),
        getCrossSigningStatus: jest.fn().mockResolvedValue({
            publicKeysOnDevice: true,
            privateKeysInSecretStorage: false,
            privateKeysCachedLocally: {
                masterKey: true,
                selfSigningKey: true,
                userSigningKey: true,
            },
        }),
        isCrossSigningReady: jest.fn().mockResolvedValue(true),
        isSecretStorageReady: jest.fn(),
        getSessionBackupPrivateKey: jest.fn(),
        getVersion: jest.fn().mockReturnValue("Version 0"),
    }),
});