Copy common fields when changing pipeline type (#1461)

Preserve common AdvancedPipelineSettings fields when switching pipeline types. This includes camera resolution, exposure settings, and stuff

photon-core/src/main/java/org/photonvision/vision/processes/PipelineManager.java

@@ -17,6 +17,7 @@
 
 package org.photonvision.vision.processes;
 
+import java.lang.reflect.Field;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Comparator;
@@ -465,6 +466,17 @@ public class PipelineManager {
         }
     }
 
+    private static List<Field> getAllFields(Class base) {
+        List<Field> ret = new ArrayList<>();
+        ret.addAll(List.of(base.getDeclaredFields()));
+        var superclazz = base.getSuperclass();
+        if (superclazz != null) {
+            ret.addAll(getAllFields(superclazz));
+        }
+
+        return ret;
+    }
+
     public void changePipelineType(int newType) {
         // Find the PipelineType proposed
         // To do this we look at all the PipelineType entries and look for one with
@@ -490,21 +502,38 @@ public class PipelineManager {
             return;
         }
 
-        // Our new settings will be totally nuked, but that's ok
-        // We *could* set things in common between the two, if we want
-        // But they're different enough it shouldn't be an issue
-        var name = getCurrentPipelineSettings().pipelineNickname;
-        var newSettings = createSettingsForType(type, name);
-
         var idx = currentPipelineIndex;
         if (idx < 0) {
             logger.error("Cannot replace non-user pipeline!");
             return;
         }
 
+        // The settings we used to have
+        var oldSettings = userPipelineSettings.get(idx);
+
+        var name = getCurrentPipelineSettings().pipelineNickname;
+        // Dummy settings to copy common fileds over
+        var newSettings = createSettingsForType(type, name);
+
+        // Copy all fields from AdvancedPipelineSettings/its superclasses from old to new
+        try {
+            for (Field field : getAllFields(AdvancedPipelineSettings.class)) {
+                Object value = field.get(oldSettings);
+                logger.debug("setting " + field.getName() + " to " + value);
+                field.set(newSettings, value);
+            }
+        } catch (Exception e) {
+            logger.error("Couldn't copy old settings", e);
+        }
+
         logger.info("Adding new pipe of type " + type + " at idx " + idx);
+
+        // type gets overritten by reflction hackery above
         newSettings.pipelineIndex = idx;
+        newSettings.pipelineType = type;
+
         userPipelineSettings.set(idx, newSettings);
+
         setPipelineInternal(idx);
         reassignIndexes();
         recreateUserPipeline();

photon-core/src/test/java/org/photonvision/vision/processes/PipelineManagerTest.java

@@ -20,15 +20,21 @@ package org.photonvision.vision.processes;
 import java.util.ArrayList;
 import java.util.List;
 import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
+import org.photonvision.common.configuration.ConfigManager;
 import org.photonvision.common.util.TestUtils;
 import org.photonvision.vision.pipeline.DriverModePipelineSettings;
 import org.photonvision.vision.pipeline.PipelineType;
 
 public class PipelineManagerTest {
+    @BeforeAll
+    public static void init() {
+        TestUtils.loadLibraries();
+    }
+
     @Test
     public void testUniqueName() {
-        TestUtils.loadLibraries();
         PipelineManager manager = new PipelineManager(new DriverModePipelineSettings(), List.of(), -1);
         manager.addPipeline(PipelineType.Reflective, "Another");
 
@@ -58,4 +64,18 @@ public class PipelineManagerTest {
         }
         Assertions.assertEquals(expected, nicks);
     }
+
+    @Test
+    public void testChangeType() {
+        // hack since we try to publish to datachangeservice
+        ConfigManager.getInstance().load();
+
+        PipelineManager manager = new PipelineManager(new DriverModePipelineSettings(), List.of(), -1);
+        // add a reflective pipeline
+        manager.addPipeline(PipelineType.Reflective, "Another");
+        manager.setIndex(0);
+        manager.getCurrentPipeline();
+        // and change
+        manager.changePipelineType(PipelineType.Aruco.baseIndex);
+    }
 }