/*
 * Copyright (C) 2023 The Android Open Source Project
 *
 * 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.
 */

package android.car.hardware.property;

import android.annotation.IntDef;
import android.annotation.NonNull;
import android.annotation.SystemApi;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

/**
 * Used to enumerate the current state of {@link
 * android.car.VehiclePropertyIds#EMERGENCY_LANE_KEEP_ASSIST_STATE}.
 *
 * <p>This enum could be extended in future releases to include additional feature states.
 * @hide
 */
@SystemApi
public class EmergencyLaneKeepAssistState {
    /**
     * This state is used as an alternative for any {@code EmergencyLaneKeepAssistState} value that
     * is not defined in the platform. Ideally, implementations of {@link
     * android.car.VehiclePropertyIds#EMERGENCY_LANE_KEEP_ASSIST_STATE} should not use this state.
     * The framework can use this field to remain backwards compatible if {@code
     * EmergencyLaneKeepAssistState} is extended to include additional states.
     */
    public static final int OTHER = 0;
    /**
     * ELKA is enabled and monitoring safety, but no safety event is detected and steering assist is
     * not activated.
     */
    public static final int ENABLED = 1;
    /**
     * ELKA is enabled and a safety event is detected. Vehicle is sending out a warning to the
     * driver indicating that there is a dangerous maneuver on the left side of the vehicle.
     */
    public static final int WARNING_LEFT = 2;
    /**
     * ELKA is enabled and a safety event is detected. Vehicle is sending out a warning to the
     * driver indicating that there is a dangerous maneuver on the right side of the vehicle.
     */
    public static final int WARNING_RIGHT = 3;
    /**
     * ELKA is enabled and currently has steering assist applied to the vehicle. Steering assist
     * nudges the vehicle towards the left, which generally means the steering wheel turns counter
     * clockwise. This is usually in response to the driver making an unsafe right lane change.
     */
    public static final int ACTIVATED_STEER_LEFT = 4;
    /**
     * ELKA is enabled and currently has steering assist applied to the vehicle. Steering assist
     * nudges the vehicle towards the right, which generally means the steering wheel turns
     * clockwise. This is usually in response to the driver making an unsafe left lane change.
     */
    public static final int ACTIVATED_STEER_RIGHT = 5;
    /**
     * Many safety feature implementations allow the driver to override said feature. This means
     * that the car has determined it should take some action, but a user decides to take over and
     * do something else. This is often done for safety reasons and to ensure that the driver can
     * always take control of the vehicle. This state should be set when the user is currently
     * overriding ELKA.
     */
    public static final int USER_OVERRIDE = 6;

    private EmergencyLaneKeepAssistState() {}

    /**
     * Returns a user-friendly representation of an {@code EmergencyLaneKeepAssistState}.
     */
    @NonNull
    public static String toString(
            @EmergencyLaneKeepAssistStateInt int emergencyLaneKeepAssistState) {
        switch (emergencyLaneKeepAssistState) {
            case OTHER:
                return "OTHER";
            case ENABLED:
                return "ENABLED";
            case WARNING_LEFT:
                return "WARNING_LEFT";
            case WARNING_RIGHT:
                return "WARNING_RIGHT";
            case ACTIVATED_STEER_LEFT:
                return "ACTIVATED_STEER_LEFT";
            case ACTIVATED_STEER_RIGHT:
                return "ACTIVATED_STEER_RIGHT";
            case USER_OVERRIDE:
                return "USER_OVERRIDE";
            default:
                return "0x" + Integer.toHexString(emergencyLaneKeepAssistState);
        }
    }

    /** @hide */
    @IntDef({OTHER, ENABLED, WARNING_LEFT, WARNING_RIGHT, ACTIVATED_STEER_LEFT,
            ACTIVATED_STEER_RIGHT, USER_OVERRIDE})
    @Retention(RetentionPolicy.SOURCE)
    public @interface EmergencyLaneKeepAssistStateInt {}
}