IAB stuff

public class MainActivity extends AndroidApplication {
    private static final String TAG = "IAB";

    /*
     * Needed only for testing.
     * Set it to false when you ready for publishing your app
     */
    private static boolean debugMode = true;

    /*
     * Any random salt (not Math.random() =) Just one word, same for all users)
     */
    private static final String key = "anyRandomSalt";

    /*
     * Public key from market. Go to Play console, select needed app and go to "Services and API",
     * and you'll find key.
     */
    private static final String publicKey = "longPublicKeyFromMarket";

    private static final int RC_REQUEST = 10001; // Any number
    private boolean billingSupported = false; // Don't change it manually
    private boolean busy = false; // Don't change it manually
    private IabHelper helper;

    /*
     * This is very important part.
     * Here you must make SKUs names from Play Console, but one cool thing here.
     * For testing without money, you can use one of 4 special names, and you should get a fake card
     * prompt in the purchase screen when you try to buy this item in your app.
     * You don't need to make changes in Play console and build public version of app.
     * Just run it on devise in build mode. And you don't neet to make
     * any changes in your AndroidManifest.xml (e.g. version) before you will ready to publish your app.
     *
     * Special names:
     * android.test.purchased, android.test.canceled, android.test.refunded, android.test.item_unavailable
     */
    private static final String SKU_ADS_FREE   = "ads_free"; // non consumable. restored even after reinstall
    private static final String SKU_MONEY_1000 = "money_1000"; // consumable. without restore after reinstall
    private static final String SKU_MONEY_3000 = "android.test.purchased"; // consumable. without restore after reinstall

    private boolean adsfree = false;
    private int money = 0;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        loadData();

        helper = new IabHelper(getApplicationContext(), publicKey);

        if (debugMode)
            helper.enableDebugLogging(true);

        helper.startSetup(new IabHelper.OnIabSetupFinishedListener() {
            public void onIabSetupFinished(IabResult result) {
                if (result.isSuccess()) {
                    billingSupported = true;
                    busy = true;
                    helper.queryInventoryAsync(gotInventoryListener);
                    log("IAB started");
                } else {
                    billingSupported = false;
                    log("Problem setting up IAB: " + result);
                }
            }
        });

        final AndroidApplicationConfiguration config = new AndroidApplicationConfiguration();
        config.useGL20     = false;
        config.useWakelock = false;

        final Resolver resolver = new Resolver() {
            @Override
            public boolean getBusyState() {
                return busy;
            }

            @Override
            public boolean getAd() {
                return adsfree;
            }

            @Override
            public int getMoney() {
                return money;
            }

            @Override
            public void buyAdsFree() {
                if (!adsfree)
                    buyItem(SKU_ADS_FREE);
            }

            @Override
            public void buyMoney1000() {
                buyItem(SKU_MONEY_1000);
            }

            @Override
            public void buyMoney3000() {
                buyItem(SKU_MONEY_3000);
            }
        };

        initialize(new Main(resolver), config);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();

        if (billingSupported()) {
            helper.dispose();
            helper = null;
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (!billingSupported())
            return;

        log("onActivityResult(" + requestCode + "," + resultCode + "," + data);

        if (helper.handleActivityResult(requestCode, resultCode, data)) {
            log("onActivityResult handled by IABUtil");
        } else {
            super.onActivityResult(requestCode, resultCode, data);
        }
    }

    @Override
    public void onResume() {
        super.onResume();

        if (billingSupported() && !busy) {
            busy = true;
            helper.queryInventoryAsync(gotInventoryListener);
        }
    }

    private void buyItem(final String sku) {
        if (!billingSupported()) {
            log("Billing is not supported");
            return;
        }

        if (busy) {
            log("Can't buy item. So busy yet");
            return;
        }

        try {
            new Thread(new Runnable() {
                @Override
                public void run() {
                    busy = true;
                    helper.launchPurchaseFlow(MainActivity.this, sku, RC_REQUEST, purchaseFinishedListener, key);
                }
            }).start();
        } catch (Exception e) {
            log("buyItem Exception: " + e);
        }
    }

    private final IabHelper.OnIabPurchaseFinishedListener purchaseFinishedListener = new IabHelper.OnIabPurchaseFinishedListener() {
        public void onIabPurchaseFinished(IabResult result, final Purchase purchase) {
            log("Purchase finished: " + result + ", purchase: " + purchase);

            if (purchaseIsNull(purchase)) {
                busy = false;
                return;
            } else if (result.isFailure()) {
                log("Purchase failure: " + result + ", purchase: " + purchase);
                busy = false;
                return;
            } else if (!verifyPayload(purchase)) {
                log("Error purchasing. Authenticity verification failed");
                busy = false;
                return;
            }

            log("Purchase successful");

            if (compareSKU(purchase, SKU_ADS_FREE)) {
                adsfree = true;
                busy = false;
            } else if (compareSKU(purchase, SKU_MONEY_1000) ||
                   compareSKU(purchase, SKU_MONEY_3000)) {
                helper.consumeAsync(purchase, consumeFinishedListener);
            }
        }
    };

    private final IabHelper.OnConsumeFinishedListener consumeFinishedListener = new IabHelper.OnConsumeFinishedListener() {
        @Override
        public void onConsumeFinished(Purchase purchase, IabResult result) {
            /*
             * Only for consumable items
             */
            if (result.isSuccess()) {
                if (compareSKU(purchase, SKU_MONEY_1000)) {
                    money += 1000;
                    log("Get + 1000$");
                } else if (compareSKU(purchase, SKU_MONEY_3000)) {
                    money += 3000;
                    log("Get + 3000$");
                }

                saveData();
            } else {
                log("Error while consuming: " + result);
            }

            log("Consumption finished: " + result + ", purchase: " + purchase);
            busy = false;
        }
    };

    private final IabHelper.QueryInventoryFinishedListener gotInventoryListener = new IabHelper.QueryInventoryFinishedListener() {
        public void onQueryInventoryFinished(IabResult result, Inventory inventory) {
            if (result.isFailure()) {
                log("InventoryFinishedListener: " + result);
                busy = false;
                return;
            }

            adsfree = checkPurchase(inventory, SKU_ADS_FREE); // non consumable

            if (consume(inventory, SKU_MONEY_1000)) return; // consumable
            if (consume(inventory, SKU_MONEY_3000)) return; // consumable

            busy = false;
        }
    };

    private boolean billingSupported() {
        return (helper != null && billingSupported);
    }

    private boolean purchaseIsNull(Purchase purchase) {
        if (purchase == null) {
            log("Purchase is null");
            return true;
        }

        return false;
    }

    private boolean checkPurchase(Inventory inventory, String name) {
        Purchase purchase = inventory.getPurchase(name);
        return (purchase != null && verifyPayload(purchase));
    }

    private boolean consume(Inventory inventory, String name) {
        if (checkPurchase(inventory, name)) {
            log("Consumed: " + name);
            helper.consumeAsync(inventory.getPurchase(name), consumeFinishedListener);
            return true;
        }

        return false;
    }

    private boolean compareSKU(Purchase purchase, String name) {
        return purchase.getSku().equals(name);
    }

    private boolean verifyPayload(Purchase purchase) {
        return purchase.getDeveloperPayload().equals(key);
    }

    private void saveData() {
        final SharedPreferences.Editor preferences = getPreferences(MODE_PRIVATE).edit();
        preferences.putInt("money", money);
        preferences.commit();
    }

    private void loadData() {
        final SharedPreferences preferences = getPreferences(MODE_PRIVATE);
        money = preferences.getInt("money", 0);
    }

    private void log(String input) {
        if (debugMode)
            Log.d(TAG, input);
    }
}