Small refactoring of BtLE actions

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/AbstractBTLEDeviceSupport.java

@@ -16,6 +16,7 @@ import java.util.Set;
 import java.util.UUID;
 
 import nodomain.freeyourgadget.gadgetbridge.service.AbstractDeviceSupport;
+import nodomain.freeyourgadget.gadgetbridge.service.btle.actions.CheckInitializedAction;
 
 /**
  * Abstract base class for all devices connected through Bluetooth Low Energy (LE) aka

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/actions/CheckInitializedAction.java

@@ -1,10 +1,9 @@
-package nodomain.freeyourgadget.gadgetbridge.service.btle;
+package nodomain.freeyourgadget.gadgetbridge.service.btle.actions;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import nodomain.freeyourgadget.gadgetbridge.impl.GBDevice;
-import nodomain.freeyourgadget.gadgetbridge.service.btle.actions.AbortTransactionAction;
 
 /**
  * A special action that is executed at the very front of the initialization

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/actions/ConditionalWriteAction.java

@@ -0,0 +1,29 @@
+package nodomain.freeyourgadget.gadgetbridge.service.btle.actions;
+
+import android.bluetooth.BluetoothGatt;
+import android.bluetooth.BluetoothGattCharacteristic;
+
+public abstract class ConditionalWriteAction extends WriteAction {
+    public ConditionalWriteAction(BluetoothGattCharacteristic characteristic) {
+        super(characteristic, null);
+    }
+
+    @Override
+    protected boolean writeValue(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, byte[] value) {
+        byte[] conditionalValue = checkCondition();
+        if (conditionalValue != null) {
+            return super.writeValue(gatt, characteristic, conditionalValue);
+        }
+        return true;
+    }
+
+    /**
+     * Checks the condition whether the write shall happen or not.
+     * Returns the actual value to be written or null in case nothing shall be written.
+     *
+     * Note that returning null will not cause run() to return false, in other words,
+     * the rest of the queue will still be executed.
+     * @return the value to be written or null to not write anything
+     */
+    protected abstract byte[] checkCondition();
+}

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/btle/actions/WriteAction.java

@@ -22,16 +22,26 @@ public class WriteAction extends BtLEAction {
 
     @Override
     public boolean run(BluetoothGatt gatt) {
-        int properties = getCharacteristic().getProperties();
+        BluetoothGattCharacteristic characteristic = getCharacteristic();
+        int properties = characteristic.getProperties();
         //TODO: expectsResult should return false if PROPERTY_WRITE_NO_RESPONSE is true, but this yelds to timing issues
         if ((properties & BluetoothGattCharacteristic.PROPERTY_WRITE) > 0 || ((properties & BluetoothGattCharacteristic.PROPERTY_WRITE_NO_RESPONSE) > 0)) {
-            if (getCharacteristic().setValue(value)) {
-                return gatt.writeCharacteristic(getCharacteristic());
-            }
+            return writeValue(gatt, characteristic, value);
         }
         return false;
     }
 
+    protected boolean writeValue(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, byte[] value) {
+        if (characteristic.setValue(value)) {
+            return gatt.writeCharacteristic(characteristic);
+        }
+        return false;
+    }
+
+    protected final byte[] getValue() {
+        return value;
+    }
+
     @Override
     public boolean expectsResult() {
         return true;

app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/miband/CheckAuthenticationNeededAction.java

@@ -1,11 +1,9 @@
 package nodomain.freeyourgadget.gadgetbridge.service.devices.miband;
 
-import android.bluetooth.BluetoothGatt;
-
 import nodomain.freeyourgadget.gadgetbridge.impl.GBDevice;
-import nodomain.freeyourgadget.gadgetbridge.service.btle.actions.PlainAction;
+import nodomain.freeyourgadget.gadgetbridge.service.btle.actions.AbortTransactionAction;
 
-public class CheckAuthenticationNeededAction extends PlainAction {
+public class CheckAuthenticationNeededAction extends AbortTransactionAction {
     private final GBDevice mDevice;
 
     public CheckAuthenticationNeededAction(GBDevice device) {
@@ -14,14 +12,14 @@ public class CheckAuthenticationNeededAction extends PlainAction {
     }
 
     @Override
-    public boolean run(BluetoothGatt gatt) {
+    protected boolean shouldAbort() {
         // the state is set in MiBandSupport.handleNotificationNotif()
         switch (mDevice.getState()) {
             case AUTHENTICATION_REQUIRED: // fall through
             case AUTHENTICATING:
-                return false; // abort the whole thing
+                return true; // abort the whole thing
             default:
-                return true;
+                return false;
         }
     }
 }