Add a NearbyScanRequest for requesting scan.

Currently only scan type and worksource are supported in the scan
request. More parameters will be added in the future.

Bug: 189355156
Test: atest NearbyUnitTests

Change-Id: I73d9e48865d33f5b13b29acac30eadc1a9eb9168
diff --git a/nearby/framework/Android.bp b/nearby/framework/Android.bp
index 5339551..8a09620 100644
--- a/nearby/framework/Android.bp
+++ b/nearby/framework/Android.bp
@@ -33,6 +33,9 @@
     srcs: [
         ":nearby-java-sources",
     ],
+    static_libs: [
+        "modules-utils-preconditions",
+    ],
 }
 
 // Defaults for SDK versions.
@@ -42,7 +45,6 @@
     target_sdk_version: "current",
 }
 
-
 // Nearby-service needs pre-jarjared version of framework-nearby so it can reference copied utility
 // classes before they are renamed.
 java_library {
@@ -55,6 +57,7 @@
     installable: false,
     visibility: [
         "//packages/modules/Nearby/service",
+        "//packages/modules/Nearby/tests",
     ],
 }
 
@@ -66,6 +69,7 @@
         "framework-nearby-defaults",
     ],
 
+    jarjar_rules: ":nearby-jarjar-rules",
     apex_available: [
         "com.android.nearby",
     ],
@@ -80,5 +84,6 @@
     ],
     permitted_packages: [
         "android.nearby",
+        "com.android.nearby",
     ],
 }
diff --git a/nearby/framework/java/android/nearby/ScanRequest.java b/nearby/framework/java/android/nearby/ScanRequest.java
new file mode 100644
index 0000000..56da371
--- /dev/null
+++ b/nearby/framework/java/android/nearby/ScanRequest.java
@@ -0,0 +1,189 @@
+/*
+ * Copyright (C) 2021 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.nearby;
+
+import android.Manifest;
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.RequiresPermission;
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.os.WorkSource;
+
+import com.android.internal.util.Preconditions;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.util.Objects;
+
+/**
+ * An encapsulation of various parameters for requesting nearby scans.
+ *
+ * @hide
+ */
+public final class ScanRequest implements Parcelable {
+
+    /** @hide **/
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef({SCAN_TYPE_FAST_PAIR, SCAN_TYPE_NEARBY_SHARE, SCAN_TYPE_NEARBY_PRESENCE,
+            SCAN_TYPE_EXPOSURE_NOTIFICATION})
+    public @interface ScanType{}
+
+    /** Scan type for scanning devices using fast pair protocol. */
+    public static final int SCAN_TYPE_FAST_PAIR = 1;
+    /** Scan type for scanning devices using nearby share protocol. */
+    public static final int SCAN_TYPE_NEARBY_SHARE = 2;
+    /** Scan type for scanning devices using nearby presence protocol. */
+    public static final int SCAN_TYPE_NEARBY_PRESENCE = 3;
+    /** Scan type for scanning devices using exposure notification protocol. */
+    public static final int SCAN_TYPE_EXPOSURE_NOTIFICATION = 4;
+
+    private final @ScanType int mScanType;
+    private final @Nullable WorkSource mWorkSource;
+
+    private ScanRequest(@ScanType int scanType, @Nullable WorkSource workSource) {
+        mScanType = scanType;
+        mWorkSource = workSource;
+    }
+
+    /**
+     * Returns the scan type for this request.
+     */
+    public @ScanType int getScanType() {
+        return mScanType;
+    }
+
+    /**
+     * Returns the work source used for power attribution of this request.
+     *
+     * @hide
+     */
+    public @Nullable WorkSource getWorkSource() {
+        return mWorkSource;
+    }
+
+    public static final Creator<ScanRequest> CREATOR = new Creator<ScanRequest>() {
+        @Override
+        public ScanRequest createFromParcel(Parcel in) {
+            return new ScanRequest(
+                    /* scanType= */ in.readInt(),
+                    /* workSource= */ in.readTypedObject(WorkSource.CREATOR));
+        }
+
+        @Override
+        public ScanRequest[] newArray(int size) {
+            return new ScanRequest[size];
+        }
+    };
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder stringBuilder = new StringBuilder();
+        stringBuilder.append("Request[")
+                .append("scanType=").append(mScanType);
+        if (mWorkSource != null && !mWorkSource.isEmpty()) {
+            stringBuilder.append(", workSource=").append(mWorkSource);
+        }
+        stringBuilder.append("]");
+        return stringBuilder.toString();
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeInt(mScanType);
+        dest.writeTypedObject(mWorkSource, /* parcelableFlags= */0);
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other instanceof ScanRequest) {
+            ScanRequest otherRequest = (ScanRequest) other;
+            return mScanType == otherRequest.mScanType
+                    && Objects.equals(mWorkSource, otherRequest.mWorkSource);
+        }
+        return false;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mScanType, mWorkSource);
+    }
+
+    /** A builder class for {@link ScanRequest}. */
+    public static final class Builder {
+        private static final int INVALID_SCAN_TYPE = -1;
+        private @ScanType int mScanType;
+        private @Nullable WorkSource mWorkSource;
+
+        /** Creates a new Builder with the given scan type. */
+        public Builder() {
+            mScanType = INVALID_SCAN_TYPE;
+            mWorkSource = null;
+        }
+
+        /**
+         * Sets the scan type for the request. The scan type must be one of the SCAN_TYPE_ constants
+         * in {@link ScanRequest}.
+         */
+        public Builder setScanType(@ScanType int scanType) {
+            mScanType = scanType;
+            return this;
+        }
+        /**
+         * Sets the work source to use for power attribution for this scan request. Defaults to
+         * empty work source, which implies the caller that sends the scan request will be used
+         * for power attribution.
+         *
+         * <p>Permission enforcement occurs when the resulting scan request is used, not when
+         * this method is invoked.
+         *
+         * @hide
+         */
+        @RequiresPermission(Manifest.permission.UPDATE_DEVICE_STATS)
+        public @NonNull Builder setWorkSource(@Nullable WorkSource workSource) {
+            this.mWorkSource = workSource;
+            return this;
+        }
+
+        /**
+         * Builds a scan request from this builder.
+         *
+         * @throws IllegalStateException if the scanType is not one of the SCAN_TYPE_ constants in
+         *         {@link ScanRequest}.
+         * @return a new nearby scan request.
+         */
+        public @NonNull ScanRequest build() {
+            Preconditions.checkState(isValidScanType(mScanType),
+                    "invalid scan type : " + mScanType
+                            + ", scan type must be one of ScanRequest#SCAN_TYPE_");
+            return new ScanRequest(mScanType, mWorkSource);
+        }
+
+        private static boolean isValidScanType(int scanType) {
+            return scanType == SCAN_TYPE_FAST_PAIR
+                    || scanType == SCAN_TYPE_NEARBY_SHARE
+                    || scanType == SCAN_TYPE_NEARBY_PRESENCE
+                    || scanType == SCAN_TYPE_EXPOSURE_NOTIFICATION;
+        }
+    }
+}