Add a hostside Java lib to read proto paths

        "//apex_available:platform",

    ],

}

genrule {

    name: "libaconfig_java_host_device_paths_src",

    srcs: ["src/HostDeviceProtosTemplate.java"],

    out: ["HostDeviceProtos.java"],

    tool_files: ["partition_aconfig_flags_paths.txt"],

    cmd: "sed -e '/TEMPLATE/{r$(location partition_aconfig_flags_paths.txt)' -e 'd}' $(in) > $(out)",

}

java_library_host {

    name: "aconfig_host_device_paths_java",

    srcs: [":libaconfig_java_host_device_paths_src"],

}

/*

 * Copyright (C) 2024 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.aconfig;

import java.io.File;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.HashSet;

import java.util.List;

import java.util.Set;

import java.util.stream.Collectors;

/**

 * A host lib that can read all aconfig proto file paths on a given device.

 */

public class HostDeviceProtos {

    /**

     * An interface that executes ADB command and return the result.

     */

    public static interface AdbCommandExecutor {

        /** Executes the ADB command. */

        String executeAdbCommand(String command);

    }

    static final String[] PATHS = {

        TEMPLATE

    };

    private static final String APEX_DIR = "/apex";

    private static final String RECURSIVELY_LIST_APEX_DIR_COMMAND = "shell find /apex | grep aconfig_flags";

    private static final String APEX_ACONFIG_PATH_SUFFIX = "/etc/aconfig_flags.pb";

    /**

     * Returns the list of all on-device aconfig proto paths from host side.

     */

    public static List<String> parsedFlagsProtoPaths(AdbCommandExecutor adbCommandExecutor) {

        ArrayList<String> paths = new ArrayList(Arrays.asList(PATHS));

        String adbCommandOutput = adbCommandExecutor.executeAdbCommand(

            RECURSIVELY_LIST_APEX_DIR_COMMAND);

        if (adbCommandOutput == null) {

            return paths;

        }

        Set<String> allFiles = new HashSet<>(Arrays.asList(adbCommandOutput.split("\n")));

        Set<String> subdirs = allFiles.stream().map(file -> {

            String[] filePaths = file.split("/");

            // The first element is "", the second element is "apex".

            return filePaths.length > 2 ? filePaths[2] : "";

        }).collect(Collectors.toSet());

        for (String prefix : subdirs) {

            // For each mainline modules, there are two directories, one <modulepackage>/,

            // and one <modulepackage>@<versioncode>/. Just read the former.

            if (prefix.contains("@")) {

                continue;

            }

            String protoPath = APEX_DIR + "/" + prefix + APEX_ACONFIG_PATH_SUFFIX;

            if (allFiles.contains(protoPath)) {

                paths.add(protoPath);

            }

        }

        return paths;

    }

}