package launchserver.command.hash;

import java.io.BufferedReader;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Collections;

import com.eclipsesource.json.Json;
import com.eclipsesource.json.JsonObject;
import com.eclipsesource.json.JsonObject.Member;
import launcher.helper.IOHelper;
import launcher.helper.LogHelper;
import launchserver.LaunchServer;
import launchserver.command.Command;
import launchserver.command.CommandException;

public final class UnindexAssetCommand extends Command {
    public UnindexAssetCommand(LaunchServer server) {
        super(server);
    }

    @Override
    public String getArgsDescription() {
        return "<dir> <index> <output-dir>";
    }

    @Override
    public String getUsageDescription() {
        return "Unindex asset dir (1.7.10+)";
    }

    @Override
    public void invoke(String... args) throws Exception {
        verifyArgs(args, 3);
        String inputAssetDirName = IOHelper.verifyFileName(args[0]);
        String indexFileName = IOHelper.verifyFileName(args[1]);
        String outputAssetDirName = IOHelper.verifyFileName(args[2]);
        Path inputAssetDir = server.updatesDir.resolve(inputAssetDirName);
        Path outputAssetDir = server.updatesDir.resolve(outputAssetDirName);
        if (outputAssetDir.equals(inputAssetDir)) {
            throw new CommandException("Indexed and unindexed asset dirs can't be same");
        }

        // Create new asset dir
        LogHelper.subInfo("Creating unindexed asset dir: '%s'", outputAssetDirName);
        Files.createDirectory(outputAssetDir);

        // Read JSON file
        JsonObject objects;
        LogHelper.subInfo("Reading asset index file: '%s'", indexFileName);
        try (BufferedReader reader = IOHelper.newReader(IndexAssetCommand.resolveIndexFile(inputAssetDir, indexFileName))) {
            objects = Json.parse(reader).asObject().get(IndexAssetCommand.OBJECTS_DIR).asObject();
        }

        // Restore objects
        LogHelper.subInfo("Unindexing %d objects", objects.size());
        for (Member member : objects) {
            String name = member.getName();
            LogHelper.subInfo("Unindexing: '%s'", name);

            // Copy hashed file to target
            String hash = member.getValue().asObject().get("hash").asString();
            Path source = IndexAssetCommand.resolveObjectFile(inputAssetDir, hash);
            IOHelper.copy(source, outputAssetDir.resolve(name));
        }

        // Finished
        server.syncUpdatesDir(Collections.singleton(outputAssetDirName));
        LogHelper.subInfo("Asset successfully unindexed: '%s'", inputAssetDirName);
    }
}