package de.diddiz.util;

import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;

import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.ByteBuffer;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.UUID;

// Adapted from https://gist.github.com/evilmidget38/26d70114b834f71fb3b4

public class UUIDFetcher {

    private static final String PROFILE_URL = "https://api.mojang.com/profiles/minecraft";
    private static final JSONParser jsonParser = new JSONParser();

    public static Map<String, UUID> getUUIDs(List<String> names) throws Exception {
        Map<String, UUID> uuidMap = new HashMap<>();
        HttpURLConnection connection = createConnection();
        String body = JSONArray.toJSONString(names);
        writeBody(connection, body);
        JSONArray array = (JSONArray) jsonParser.parse(new InputStreamReader(connection.getInputStream()));
        for (Object profile : array) {
            JSONObject jsonProfile = (JSONObject) profile;
            String id = (String) jsonProfile.get("id");
            String name = (String) jsonProfile.get("name");
            UUID uuid = UUIDFetcher.getUUID(id);
            uuidMap.put(name, uuid);
        }
        return uuidMap;
    }

    private static void writeBody(HttpURLConnection connection, String body) throws Exception {
        OutputStream stream = connection.getOutputStream();
        stream.write(body.getBytes());
        stream.flush();
        stream.close();
    }

    private static HttpURLConnection createConnection() throws Exception {
        URL url = new URL(PROFILE_URL);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setRequestMethod("POST");
        connection.setRequestProperty("Content-Type", "application/json");
        connection.setUseCaches(false);
        connection.setDoInput(true);
        connection.setDoOutput(true);
        return connection;
    }

    private static UUID getUUID(String id) {
        return UUID.fromString(id.substring(0, 8) + "-" + id.substring(8, 12) + "-" + id.substring(12, 16) + "-" + id.substring(16, 20) + "-" + id.substring(20, 32));
    }

    public static byte[] toBytes(UUID uuid) {
        ByteBuffer byteBuffer = ByteBuffer.wrap(new byte[16]);
        byteBuffer.putLong(uuid.getMostSignificantBits());
        byteBuffer.putLong(uuid.getLeastSignificantBits());
        return byteBuffer.array();
    }

    public static UUID fromBytes(byte[] array) {
        if (array.length != 16) {
            throw new IllegalArgumentException("Illegal byte array length: " + array.length);
        }
        ByteBuffer byteBuffer = ByteBuffer.wrap(array);
        long mostSignificant = byteBuffer.getLong();
        long leastSignificant = byteBuffer.getLong();
        return new UUID(mostSignificant, leastSignificant);
    }

}