Add common pathing code and SimplePathing module

src/main/java/com/replaymod/pathing/player/AbstractTimelinePlayer.java

@@ -0,0 +1,90 @@
+package com.replaymod.pathing.player;
+
+import com.google.common.base.Function;
+import com.google.common.collect.FluentIterable;
+import com.google.common.collect.Ordering;
+import com.google.common.primitives.Longs;
+import com.google.common.util.concurrent.ListenableFuture;
+import com.google.common.util.concurrent.SettableFuture;
+import com.replaymod.pathing.path.Keyframe;
+import com.replaymod.pathing.path.Path;
+import com.replaymod.pathing.path.Timeline;
+import com.replaymod.replay.ReplayHandler;
+import net.minecraftforge.fml.common.FMLCommonHandler;
+import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
+import net.minecraftforge.fml.common.gameevent.TickEvent;
+
+import javax.annotation.Nullable;
+import java.util.Iterator;
+
+/**
+ * Plays a timeline.
+ */
+public abstract class AbstractTimelinePlayer {
+    private final ReplayHandler replayHandler;
+    private Timeline timeline;
+    private long lastTimestamp;
+    private ListenableFuture<Void> future;
+    private SettableFuture<Void> settableFuture;
+
+    public AbstractTimelinePlayer(ReplayHandler replayHandler) {
+        this.replayHandler = replayHandler;
+    }
+
+    public ListenableFuture<Void> start(Timeline timeline) {
+        this.timeline = timeline;
+
+        Iterator<Keyframe> iter = FluentIterable.from(timeline.getPaths())
+                .transformAndConcat(new Function<Path, Iterable<Keyframe>>() {
+            @Nullable
+            @Override
+            public Iterable<Keyframe> apply(@Nullable Path input) {
+                assert input != null;
+                return input.getKeyframes();
+            }
+        }).iterator();
+        if (!iter.hasNext()) {
+            lastTimestamp = 0;
+        } else {
+            lastTimestamp = new Ordering<Keyframe>() {
+                @Override
+                public int compare(@Nullable Keyframe left, @Nullable Keyframe right) {
+                    assert left != null;
+                    assert right != null;
+                    return Longs.compare(left.getTime(), right.getTime());
+                }
+            }.max(iter).getTime();
+        }
+
+        replayHandler.getReplaySender().setSyncModeAndWait();
+        FMLCommonHandler.instance().bus().register(this);
+        return future = settableFuture = SettableFuture.create();
+    }
+
+    public ListenableFuture<Void> getFuture() {
+        return future;
+    }
+
+    public boolean isActive() {
+        return future != null && !future.isDone();
+    }
+
+    @SubscribeEvent
+    public void onTick(TickEvent.RenderTickEvent event) {
+        if (future.isDone()) {
+            replayHandler.getReplaySender().setAsyncMode(true);
+            FMLCommonHandler.instance().bus().unregister(this);
+            return;
+        }
+        long time = getTimePassed();
+        if (time > lastTimestamp) {
+            time = lastTimestamp;
+        }
+        timeline.applyToGame(time, replayHandler);
+        if (time == lastTimestamp) {
+            settableFuture.set(null);
+        }
+    }
+
+    public abstract long getTimePassed();
+}