/*
 * 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.app.appsearch;

import android.annotation.NonNull;
import android.annotation.Nullable;
import android.app.appsearch.safeparcel.PackageIdentifierParcel;

import java.util.Objects;

/** This class represents a uniquely identifiable package. */
// TODO(b/384721898): Switch to JSpecify annotations
@SuppressWarnings("JSpecifyNullness")
public class PackageIdentifier {
    private final @NonNull PackageIdentifierParcel mPackageIdentifierParcel;

    /**
     * Creates a unique identifier for a package.
     *
     * <p>SHA-256 certificate digests for a signed application can be retrieved with the <a
     * href="{@docRoot}studio/command-line/apksigner/">apksigner tool</a> that is part of the
     * Android SDK build tools. Use {@code apksigner verify --print-certs path/to/apk.apk} to
     * retrieve the SHA-256 certificate digest for the target application. Once retrieved, the
     * SHA-256 certificate digest should be converted to a {@code byte[]} by decoding it in base16:
     *
     * <pre>
     * new android.content.pm.Signature(outputDigest).toByteArray();
     * </pre>
     *
     * @param packageName Name of the package.
     * @param sha256Certificate SHA-256 certificate digest of the package.
     */
    public PackageIdentifier(@NonNull String packageName, @NonNull byte[] sha256Certificate) {
        Objects.requireNonNull(packageName);
        Objects.requireNonNull(sha256Certificate);
        mPackageIdentifierParcel = new PackageIdentifierParcel(packageName, sha256Certificate);
    }

    /** @hide */
    public PackageIdentifier(@NonNull PackageIdentifierParcel packageIdentifierParcel) {
        mPackageIdentifierParcel = Objects.requireNonNull(packageIdentifierParcel);
    }

    /**
     * Returns the {@link PackageIdentifierParcel} holding the values for this {@link
     * PackageIdentifier}.
     *
     * @hide
     */
    public @NonNull PackageIdentifierParcel getPackageIdentifierParcel() {
        return mPackageIdentifierParcel;
    }

    /** Returns the name for a package. */
    public @NonNull String getPackageName() {
        return mPackageIdentifierParcel.getPackageName();
    }

    /** Returns the SHA-256 certificate for a package. */
    public @NonNull byte[] getSha256Certificate() {
        return mPackageIdentifierParcel.getSha256Certificate();
    }

    @Override
    public boolean equals(@Nullable Object obj) {
        if (this == obj) {
            return true;
        }
        if (!(obj instanceof PackageIdentifier)) {
            return false;
        }
        final PackageIdentifier other = (PackageIdentifier) obj;
        return mPackageIdentifierParcel.equals(other.getPackageIdentifierParcel());
    }

    @Override
    public int hashCode() {
        return mPackageIdentifierParcel.hashCode();
    }
}