Refactor batch events (#11995)

* create new abstract class for batch event framework

* adjust CardUtil.getEventTargets to support new framework

* update TappedBatchEvent to new framework

* update UntappedBatchEvent to new framework

* slight cleanup

* update LifeLostBatchEvent to new framework

* update ZoneChangeBatchEvent to new framework

* complete refactor by moving damage events to new framework

* remove old code no longer used

* clean up some nonsense code in star wars card

* fix watcher checking id before event type

* fix wrong id usage

* fix missed wrong id usage

Mage/src/main/java/mage/game/events/BatchEvent.java

@@ -0,0 +1,101 @@
+package mage.game.events;
+
+import java.util.HashSet;
+import java.util.Objects;
+import java.util.Set;
+import java.util.UUID;
+import java.util.stream.Collectors;
+
+/**
+ * Special events created by game engine to track batches of events that occur simultaneously,
+ * for triggers that need such information
+ * @author xenohedron
+ */
+public abstract class BatchEvent<T extends GameEvent> extends GameEvent {
+
+    private final Set<T> events = new HashSet<>();
+    private final boolean singleTargetId;
+
+    /**
+     * @param eventType specific type of event
+     * @param singleTargetId if true, all included events must have same target id
+     * @param firstEvent added to initialize the batch (batch is never empty)
+     */
+    protected BatchEvent(EventType eventType, boolean singleTargetId, T firstEvent) {
+        super(eventType, (singleTargetId ? firstEvent.getTargetId() : null), null, null);
+        this.singleTargetId = singleTargetId;
+        if (firstEvent instanceof BatchEvent) { // sanity check, if you need it then think twice and research carefully
+            throw new UnsupportedOperationException("Wrong code usage: nesting batch events not supported");
+        }
+        this.addEvent(firstEvent);
+    }
+
+    /**
+     * For alternate event structure logic used by ZoneChangeBatchEvent, list of events starts empty.
+     */
+    protected BatchEvent(EventType eventType) {
+        super(eventType, null, null, null);
+        this.singleTargetId = false;
+    }
+
+    public void addEvent(T event) {
+        if (singleTargetId && !getTargetId().equals(event.getTargetId())) {
+            throw new IllegalStateException("Wrong code usage. Batch event initiated with single target id, but trying to add event with different target id");
+        }
+        this.events.add(event);
+    }
+
+    public Set<T> getEvents() {
+        return events;
+    }
+
+    public Set<UUID> getTargetIds() {
+        return events.stream()
+                .map(GameEvent::getTargetId)
+                .filter(Objects::nonNull)
+                .collect(Collectors.toSet());
+    }
+
+    public Set<UUID> getSourceIds() {
+        return events.stream()
+                .map(GameEvent::getSourceId)
+                .filter(Objects::nonNull)
+                .collect(Collectors.toSet());
+    }
+
+    public Set<UUID> getPlayerIds() {
+        return events.stream()
+                .map(GameEvent::getPlayerId)
+                .filter(Objects::nonNull)
+                .collect(Collectors.toSet());
+    }
+
+    @Override
+    public int getAmount() {
+        return events
+                .stream()
+                .mapToInt(GameEvent::getAmount)
+                .sum();
+    }
+
+    @Override // events can store a diff value, so search it from events list instead
+    public UUID getTargetId() {
+        if (singleTargetId) {
+            return super.getTargetId();
+        }
+        throw new IllegalStateException("Wrong code usage. Must search value from a getEvents list or use CardUtil.getEventTargets(event)");
+    }
+
+    @Override // events can store a diff value, so search it from events list instead
+    @Deprecated // no use case currently supported
+    public UUID getSourceId() {
+        throw new IllegalStateException("Wrong code usage. Must search value from a getEvents list");
+    }
+
+    @Override // events can store a diff value, so search it from events list instead
+    @Deprecated // no use case currently supported
+    public UUID getPlayerId() {
+        throw new IllegalStateException("Wrong code usage. Must search value from a getEvents list");
+    }
+
+}