package hu.dpal.phonegap.plugins;

import org.apache.cordova.CallbackContext;
import org.apache.cordova.CordovaPlugin;
import org.apache.cordova.CordovaWebView;
import org.json.JSONArray;
import org.json.JSONException;

import android.content.Context;
import android.provider.Settings.Secure;
import android.util.Log;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.UUID;

public class UniqueDeviceID extends CordovaPlugin {

    public static final String TAG = "UniqueDeviceID";
    private static String sID = null;
    private static final String INSTALLATION = "INSTALLATION";
    public CallbackContext callbackContext;

    @Override
    public boolean execute(String action, JSONArray args, CallbackContext callbackContext) throws JSONException {
        this.callbackContext = callbackContext;
        try {
            if (action.equals("get")) {
                getUniqueId();
            } else {
                this.callbackContext.error("Invalid action");
                return false;
            }
        } catch(Exception e ) {
            this.callbackContext.error("Exception occurred: ".concat(e.getMessage()));
            return false;
        }
        return true;

    }

    protected void getUniqueId(){
        try {
            Context context = cordova.getActivity().getApplicationContext();

            String uuid;
            String androidID = Secure.getString(context.getContentResolver(), Secure.ANDROID_ID);

            if ("9774d56d682e549c".equals(androidID) || androidID == null) {
                String deviceID = getDeviceId(context);
                if (deviceID == null) {
                    uuid = UUID.randomUUID().toString();
                } else {
                    uuid = deviceID;
                }
            } else {
                uuid = androidID;
            }

            uuid = uuid.replace("-", "");
            uuid = String.format("%32s", uuid).replace(' ', '0');
            uuid = uuid.substring(0, 32);
            uuid = uuid.replaceAll("(\\w{8})(\\w{4})(\\w{4})(\\w{4})(\\w{12})", "$1-$2-$3-$4-$5");

            this.callbackContext.success(uuid);
        } catch(Exception e ) {
            this.callbackContext.error("Exception occurred: ".concat(e.getMessage()));
        }
    }

    public synchronized static String getDeviceId(Context context) {
        if (sID == null) {
            File installation = new File(context.getFilesDir(), INSTALLATION);
            try {
                if (!installation.exists())
                    writeInstallationFile(installation);
                sID = readInstallationFile(installation);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
        return sID;
    }

    private static String readInstallationFile(File installation) throws IOException {
        RandomAccessFile f = new RandomAccessFile(installation, "r");
        byte[] bytes = new byte[(int) f.length()];
        f.readFully(bytes);
        f.close();
        return new String(bytes);
    }

    private static void writeInstallationFile(File installation) throws IOException {
        FileOutputStream out = new FileOutputStream(installation);
        String id = UUID.randomUUID().toString();
        out.write(id.getBytes());
        out.close();
    }
}