/*
 * Copyright 2020 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.uwb;

import android.annotation.IntDef;
import android.annotation.IntRange;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.SuppressLint;
import android.annotation.SystemApi;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.PersistableBundle;
import android.os.SystemClock;
import android.uwb.util.PersistableBundleUtils;

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

/**
 * Representation of a ranging measurement between the local device and a remote device
 *
 * @hide
 */
@SystemApi
public final class RangingMeasurement implements Parcelable {
    public static final int RSSI_UNKNOWN = -128;
    public static final int RSSI_MIN = -127;
    public static final int RSSI_MAX = -1;

    private final UwbAddress mRemoteDeviceAddress;
    private final @Status int mStatus;
    private final long mElapsedRealtimeNanos;
    private final DistanceMeasurement mDistanceMeasurement;
    private final AngleOfArrivalMeasurement mAngleOfArrivalMeasurement;
    private final AngleOfArrivalMeasurement mDestinationAngleOfArrivalMeasurement;
    private final @LineOfSight int mLineOfSight;
    private final @MeasurementFocus int mMeasurementFocus;
    private final int mRssiDbm;
    private final PersistableBundle mRangingMeasurementMetadata;

    private RangingMeasurement(@NonNull UwbAddress remoteDeviceAddress, @Status int status,
            long elapsedRealtimeNanos, @Nullable DistanceMeasurement distanceMeasurement,
            @Nullable AngleOfArrivalMeasurement angleOfArrivalMeasurement,
            @Nullable AngleOfArrivalMeasurement destinationAngleOfArrivalMeasurement,
            @LineOfSight int lineOfSight, @MeasurementFocus int measurementFocus,
            @IntRange(from = RSSI_UNKNOWN, to = RSSI_MAX) int rssiDbm,
            PersistableBundle rangingMeasurementMetadata) {
        mRemoteDeviceAddress = remoteDeviceAddress;
        mStatus = status;
        mElapsedRealtimeNanos = elapsedRealtimeNanos;
        mDistanceMeasurement = distanceMeasurement;
        mAngleOfArrivalMeasurement = angleOfArrivalMeasurement;
        mDestinationAngleOfArrivalMeasurement = destinationAngleOfArrivalMeasurement;
        mLineOfSight = lineOfSight;
        mMeasurementFocus = measurementFocus;
        mRssiDbm = rssiDbm;
        mRangingMeasurementMetadata = rangingMeasurementMetadata;
    }

    /**
     * Get the remote device's {@link UwbAddress}
     *
     * @return the remote device's {@link UwbAddress}
     */
    @NonNull
    public UwbAddress getRemoteDeviceAddress() {
        return mRemoteDeviceAddress;
    }

    /**
     * @hide
     */
    @Retention(RetentionPolicy.SOURCE)
    @IntDef(value = {
            RANGING_STATUS_SUCCESS,
            RANGING_STATUS_FAILURE_OUT_OF_RANGE,
            RANGING_STATUS_FAILURE_UNKNOWN_ERROR})
    public @interface Status {}

    /**
     * Ranging attempt was successful for this device
     */
    public static final int RANGING_STATUS_SUCCESS = 0;

    /**
     * Ranging failed for this device because it is out of range
     */
    public static final int RANGING_STATUS_FAILURE_OUT_OF_RANGE = 1;

    /**
     * Ranging failed for this device because of unknown error
     */
    public static final int RANGING_STATUS_FAILURE_UNKNOWN_ERROR = -1;

    /**
     * Get the status of this ranging measurement
     *
     * <p>Possible values are
     * {@link #RANGING_STATUS_SUCCESS},
     * {@link #RANGING_STATUS_FAILURE_OUT_OF_RANGE},
     * {@link #RANGING_STATUS_FAILURE_UNKNOWN_ERROR}.
     *
     * @return the status of the ranging measurement
     */
    @Status
    public int getStatus() {
        return mStatus;
    }

    /**
     * Timestamp of this ranging measurement in time since boot nanos in the same namespace as
     * {@link SystemClock#elapsedRealtimeNanos()}
     *
     * @return timestamp of ranging measurement in nanoseconds
     */
    @SuppressLint("MethodNameUnits")
    public long getElapsedRealtimeNanos() {
        return mElapsedRealtimeNanos;
    }

    /**
     * Get the distance measurement
     *
     * @return a {@link DistanceMeasurement} or null if {@link #getStatus()} !=
     *         {@link #RANGING_STATUS_SUCCESS}
     */
    @Nullable
    public DistanceMeasurement getDistanceMeasurement() {
        return mDistanceMeasurement;
    }

    /**
     * Get the angle of arrival measurement
     *
     * @return an {@link AngleOfArrivalMeasurement} or null if {@link #getStatus()} !=
     *         {@link #RANGING_STATUS_SUCCESS}
     */
    @Nullable
    public AngleOfArrivalMeasurement getAngleOfArrivalMeasurement() {
        return mAngleOfArrivalMeasurement;
    }

    /**
     * Get the angle of arrival measurement at the destination.
     *
     * @return an {@link AngleOfArrivalMeasurement} or null if {@link #getStatus()} !=
     *         {@link #RANGING_STATUS_SUCCESS}
     */
    @Nullable
    public AngleOfArrivalMeasurement getDestinationAngleOfArrivalMeasurement() {
        return mDestinationAngleOfArrivalMeasurement;
    }

    /**
     * @hide
     */
    @Retention(RetentionPolicy.SOURCE)
    @IntDef(value = {
            LOS,
            NLOS,
            LOS_UNDETERMINED})
    public @interface LineOfSight {}

    /**
     * If measurement was in line of sight.
     */
    public static final int LOS = 0;

    /**
     * If measurement was not in line of sight.
     */
    public static final int NLOS = 1;

    /**
     * Unable to determine whether the measurement was in line of sight or not.
     */
    public static final int LOS_UNDETERMINED = 0xFF;

    /**
     * Get whether the measurement was in Line of sight or non-line of sight.
     *
     * @return whether the measurement was in line of sight or not
     */
    public @LineOfSight int getLineOfSight() {
        return mLineOfSight;
    }

    /**
     * Get the measured RSSI in dBm
     */
    public @IntRange(from = RSSI_UNKNOWN, to = RSSI_MAX) int getRssiDbm() {
        return mRssiDbm;
    }

    /**
     * @hide
     */
    @Retention(RetentionPolicy.SOURCE)
    @IntDef(value = {
            MEASUREMENT_FOCUS_NONE,
            MEASUREMENT_FOCUS_RANGE,
            MEASUREMENT_FOCUS_ANGLE_OF_ARRIVAL_AZIMUTH,
            MEASUREMENT_FOCUS_ANGLE_OF_ARRIVAL_ELEVATION})
    public @interface MeasurementFocus {}

    /**
     * Ranging measurement was done with no particular focus in terms of antenna selection.
     */
    public static final int MEASUREMENT_FOCUS_NONE = 0;

    /**
     * Ranging measurement was done with a focus on range calculation in terms of antenna
     * selection.
     */
    public static final int MEASUREMENT_FOCUS_RANGE = 1;

    /**
     * Ranging measurement was done with a focus on Angle of arrival azimuth calculation in terms of
     * antenna selection.
     */
    public static final int MEASUREMENT_FOCUS_ANGLE_OF_ARRIVAL_AZIMUTH = 2;

    /**
     * Ranging measurement was done with a focus on Angle of arrival elevation calculation in terms
     * of antenna selection.
     */
    public static final int MEASUREMENT_FOCUS_ANGLE_OF_ARRIVAL_ELEVATION = 3;

    /**
     * Gets the measurement focus in terms of antenna used for this measurement.
     *
     * @return focus of this measurement.
     */
    public @MeasurementFocus int getMeasurementFocus() {
        return mMeasurementFocus;
    }

    /**
     * Gets ranging measurement metadata passed by vendor
     *
     * @return vendor data for ranging measurement
     */
    @NonNull
    public PersistableBundle getRangingMeasurementMetadata() {
        return mRangingMeasurementMetadata;
    }

    /**
     * @hide
     */
    @Override
    public boolean equals(@Nullable Object obj) {
        if (this == obj) {
            return true;
        }

        if (obj instanceof RangingMeasurement) {
            RangingMeasurement other = (RangingMeasurement) obj;
            return Objects.equals(mRemoteDeviceAddress, other.getRemoteDeviceAddress())
                    && mStatus == other.getStatus()
                    && mElapsedRealtimeNanos == other.getElapsedRealtimeNanos()
                    && Objects.equals(mDistanceMeasurement, other.getDistanceMeasurement())
                    && Objects.equals(
                            mAngleOfArrivalMeasurement, other.getAngleOfArrivalMeasurement())
                    && Objects.equals(
                            mDestinationAngleOfArrivalMeasurement,
                            other.getDestinationAngleOfArrivalMeasurement())
                    && mLineOfSight == other.getLineOfSight()
                    && mMeasurementFocus == other.getMeasurementFocus()
                    && mRssiDbm == other.getRssiDbm()
                    && PersistableBundleUtils.isEqual(mRangingMeasurementMetadata,
                    other.mRangingMeasurementMetadata);
        }
        return false;
    }

    /**
     * @hide
     */
    @Override
    public int hashCode() {
        return Objects.hash(mRemoteDeviceAddress, mStatus, mElapsedRealtimeNanos,
                mDistanceMeasurement, mAngleOfArrivalMeasurement,
                mDestinationAngleOfArrivalMeasurement, mLineOfSight, mMeasurementFocus, mRssiDbm,
                PersistableBundleUtils.getHashCode(mRangingMeasurementMetadata));
    }

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(@NonNull Parcel dest, int flags) {
        dest.writeParcelable(mRemoteDeviceAddress, flags);
        dest.writeInt(mStatus);
        dest.writeLong(mElapsedRealtimeNanos);
        dest.writeParcelable(mDistanceMeasurement, flags);
        dest.writeParcelable(mAngleOfArrivalMeasurement, flags);
        dest.writeParcelable(mDestinationAngleOfArrivalMeasurement, flags);
        dest.writeInt(mLineOfSight);
        dest.writeInt(mMeasurementFocus);
        dest.writeInt(mRssiDbm);
        dest.writePersistableBundle(mRangingMeasurementMetadata);
    }

    public static final @android.annotation.NonNull Creator<RangingMeasurement> CREATOR =
            new Creator<RangingMeasurement>() {
                @Override
                public RangingMeasurement createFromParcel(Parcel in) {
                    Builder builder = new Builder();
                    builder.setRemoteDeviceAddress(
                            in.readParcelable(UwbAddress.class.getClassLoader()));
                    builder.setStatus(in.readInt());
                    builder.setElapsedRealtimeNanos(in.readLong());
                    builder.setDistanceMeasurement(
                            in.readParcelable(DistanceMeasurement.class.getClassLoader()));
                    builder.setAngleOfArrivalMeasurement(
                            in.readParcelable(AngleOfArrivalMeasurement.class.getClassLoader()));
                    builder.setDestinationAngleOfArrivalMeasurement(
                            in.readParcelable(AngleOfArrivalMeasurement.class.getClassLoader()));
                    builder.setLineOfSight(in.readInt());
                    builder.setMeasurementFocus(in.readInt());
                    builder.setRssiDbm(in.readInt());
                    PersistableBundle metadata =
                            in.readPersistableBundle(getClass().getClassLoader());
                    if (metadata != null) builder.setRangingMeasurementMetadata(metadata);
                    return builder.build();
                }

                @Override
                public RangingMeasurement[] newArray(int size) {
                    return new RangingMeasurement[size];
                }
    };

    /** @hide **/
    @Override
    public String toString() {
        return "RangingMeasurement["
                + "remote device address:" + mRemoteDeviceAddress
                + ", distance measurement: " + mDistanceMeasurement
                + ", aoa measurement: " + mAngleOfArrivalMeasurement
                + ", dest aoa measurement: " + mDestinationAngleOfArrivalMeasurement
                + ", lineOfSight: " + mLineOfSight
                + ", measurementFocus: " + mMeasurementFocus
                + ", rssiDbm: " + mRssiDbm
                + ", ranging measurement metadata: " + mRangingMeasurementMetadata
                + ", elapsed real time nanos: " + mElapsedRealtimeNanos
                + ", status: " + mStatus
                + "]";
    }

    /**
     * Builder for a {@link RangingMeasurement} object.
     */
    public static final class Builder {
        private UwbAddress mRemoteDeviceAddress = null;
        private @Status int mStatus = RANGING_STATUS_FAILURE_UNKNOWN_ERROR;
        private long mElapsedRealtimeNanos = -1L;
        private DistanceMeasurement mDistanceMeasurement = null;
        private AngleOfArrivalMeasurement mAngleOfArrivalMeasurement = null;
        private AngleOfArrivalMeasurement mDestinationAngleOfArrivalMeasurement = null;
        private @LineOfSight int mLineOfSight = LOS_UNDETERMINED;
        private @MeasurementFocus int mMeasurementFocus = MEASUREMENT_FOCUS_NONE;
        private int mRssiDbm = RSSI_UNKNOWN;
        private PersistableBundle mRangingMeasurementMetadata = null;

        /**
         * Set the remote device address that this measurement is for
         *
         * @param remoteDeviceAddress remote device's address
         */
        @NonNull
        public Builder setRemoteDeviceAddress(@NonNull UwbAddress remoteDeviceAddress) {
            mRemoteDeviceAddress = remoteDeviceAddress;
            return this;
        }

        /**
         * Set the status of ranging measurement
         *
         * @param status the status of the ranging measurement
         */
        @NonNull
        public Builder setStatus(@Status int status) {
            mStatus = status;
            return this;
        }

        /**
         * Set the elapsed realtime in nanoseconds when the ranging measurement occurred
         *
         * @param elapsedRealtimeNanos time the ranging measurement occurred
         */
        @NonNull
        public Builder setElapsedRealtimeNanos(long elapsedRealtimeNanos) {
            if (elapsedRealtimeNanos < 0) {
                throw new IllegalArgumentException("elapsedRealtimeNanos must be >= 0");
            }
            mElapsedRealtimeNanos = elapsedRealtimeNanos;
            return this;
        }

        /**
         * Set the {@link DistanceMeasurement}
         *
         * @param distanceMeasurement the distance measurement for this ranging measurement
         */
        @NonNull
        public Builder setDistanceMeasurement(@NonNull DistanceMeasurement distanceMeasurement) {
            mDistanceMeasurement = distanceMeasurement;
            return this;
        }

        /**
         * Set the {@link AngleOfArrivalMeasurement}
         *
         * @param angleOfArrivalMeasurement the angle of arrival measurement for this ranging
         *                                  measurement
         */
        @NonNull
        public Builder setAngleOfArrivalMeasurement(
                @NonNull AngleOfArrivalMeasurement angleOfArrivalMeasurement) {
            mAngleOfArrivalMeasurement = angleOfArrivalMeasurement;
            return this;
        }

        /**
         * Set the {@link AngleOfArrivalMeasurement} at the destination.
         *
         * @param angleOfArrivalMeasurement the angle of arrival measurement for this ranging
         *                                  measurement
         */
        @NonNull
        public Builder setDestinationAngleOfArrivalMeasurement(
                @NonNull AngleOfArrivalMeasurement angleOfArrivalMeasurement) {
            mDestinationAngleOfArrivalMeasurement = angleOfArrivalMeasurement;
            return this;
        }

        /**
         * Set whether the measurement was in Line of sight or non-line of sight.
         *
         * @param lineOfSight whether the measurement was in line of sight or not
         */
        @NonNull
        public Builder setLineOfSight(@LineOfSight int lineOfSight) {
            mLineOfSight = lineOfSight;
            return this;
        }

        /**
         * Sets the measurement focus in terms of antenna used for this measurement.
         *
         * @param measurementFocus focus of this measurement.
         */
        @NonNull
        public Builder setMeasurementFocus(@MeasurementFocus int measurementFocus) {
            mMeasurementFocus = measurementFocus;
            return this;
        }

        /**
         * Set the RSSI in dBm
         *
         * @param rssiDbm the measured RSSI in dBm
         */
        @NonNull
        public Builder setRssiDbm(@IntRange(from = RSSI_UNKNOWN, to = RSSI_MAX) int rssiDbm) {
            if (rssiDbm != RSSI_UNKNOWN && (rssiDbm < RSSI_MIN || rssiDbm > RSSI_MAX)) {
                throw new IllegalArgumentException("Invalid rssiDbm: " + rssiDbm);
            }
            mRssiDbm = rssiDbm;
            return this;
        }

        /**
         * Set Ranging measurement metadata
         *
         * @param rangingMeasurementMetadata vendor data per ranging measurement
         *
         * @throws IllegalStateException if rangingMeasurementMetadata is null
         */
        @NonNull
        public Builder setRangingMeasurementMetadata(@NonNull
                PersistableBundle rangingMeasurementMetadata) {
            if (rangingMeasurementMetadata == null) {
                throw new IllegalStateException("Expected non-null rangingMeasurementMetadata");
            }
            mRangingMeasurementMetadata = rangingMeasurementMetadata;
            return this;
        }

        /**
         * Build the {@link RangingMeasurement} object
         *
         * @throws IllegalStateException if a distance or angle of arrival measurement is provided
         *                               but the measurement was not successful, if the
         *                               elapsedRealtimeNanos of the measurement is invalid, or
         *                               if no remote device address is set
         */
        @NonNull
        public RangingMeasurement build() {
            if (mStatus != RANGING_STATUS_SUCCESS) {
                if (mDistanceMeasurement != null) {
                    throw new IllegalStateException(
                            "Distance Measurement must be null if ranging is not successful");
                }

                if (mAngleOfArrivalMeasurement != null) {
                    throw new IllegalStateException(
                            "Angle of Arrival must be null if ranging is not successful");
                }

                // Destination AOA is optional according to the spec.
            }

            if (mRemoteDeviceAddress == null) {
                throw new IllegalStateException("No remote device address was set");
            }

            if (mElapsedRealtimeNanos < 0) {
                throw new IllegalStateException(
                        "elapsedRealtimeNanos must be >=0: " + mElapsedRealtimeNanos);
            }

            return new RangingMeasurement(mRemoteDeviceAddress, mStatus, mElapsedRealtimeNanos,
                    mDistanceMeasurement, mAngleOfArrivalMeasurement,
                    mDestinationAngleOfArrivalMeasurement, mLineOfSight, mMeasurementFocus,
                    mRssiDbm, mRangingMeasurementMetadata);
        }
    }
}