-package era.mi.logic.timeline;
-
-import java.util.ArrayList;
-import java.util.List;
-import java.util.PriorityQueue;
-import java.util.function.BooleanSupplier;
-import java.util.function.Consumer;
-import java.util.function.LongSupplier;
-
-/**
- * Orders Events by the time they are due to be executed. Can execute Events individually.
- *
- * @author Fabian Stemmler
- *
- */
-public class Timeline
-{
- private PriorityQueue<InnerEvent> events;
- private LongSupplier time;
- private long lastTimeUpdated = 0;
-
- private final List<Consumer<TimelineEvent>> eventAddedListener;
-
- public Timeline(int initCapacity)
- {
- events = new PriorityQueue<InnerEvent>(initCapacity);
-
- eventAddedListener = new ArrayList<>();
- time = () -> lastTimeUpdated;
- }
-
- /**
- * @param timestamp exclusive
- * @return true if the first event is later than the timestamp
- */
- public BooleanSupplier laterThan(long timestamp)
- {
- return () -> timeCmp(events.peek().getTiming(), timestamp) > 0;
- }
-
- public boolean hasNext()
- {
- return !events.isEmpty();
- }
-
- /**
- * Executes all events at the next timestamp, at which there are any
- */
- public void executeNext()
- {
- InnerEvent first = events.peek();
- if (first != null)
- executeUntil(laterThan(first.getTiming()), -1);
- }
-
- public void executeAll()
- {
- while (hasNext())
- executeNext();
- }
-
- /**
- * Executes all events until a given condition is met. The simulation process can be constrained by a real world timestamp.
- *
- * @param condition the condition until which the events are be processed
- * @param stopMillis the System.currentTimeMillis() when simulation definitely needs to stop. A value of -1 means no timeout.
- * @return State of the event execution
- * @formatter:off
- * <code>NOTHING_DONE</code> if the {@link Timeline} was already empty
- * <code>EXEC_OUT_OF_TIME</code> if the given maximum time was reached
- * <code>EXEC_UNTIL_CONDITION</code> if the condition was met
- * <code>EXEC_UNTIL_EMPTY</code> if events were executed until the {@link Timeline} was empty
- * @formatter:on
- * @author Christian Femers, Fabian Stemmler
- */
- public ExecutionResult executeUntil(BooleanSupplier condition, long stopMillis)
- {
- if (events.isEmpty())
- {
- lastTimeUpdated = getSimulationTime();
- return ExecutionResult.NOTHING_DONE;
- }
- int checkStop = 0;
- InnerEvent first = events.peek();
- while (hasNext() && !condition.getAsBoolean())
- {
- events.remove();
- lastTimeUpdated = first.getTiming();
- first.run();
- // Don't check after every run
- checkStop = (checkStop + 1) % 10;
- if (checkStop == 0 && System.currentTimeMillis() >= stopMillis)
- return ExecutionResult.EXEC_OUT_OF_TIME;
- first = events.peek();
- }
- lastTimeUpdated = getSimulationTime();
- return hasNext() ? ExecutionResult.EXEC_UNTIL_EMPTY : ExecutionResult.EXEC_UNTIL_CONDITION;
- }
-
- public void setTimeFunction(LongSupplier time)
- {
- this.time = time;
- }
-
- public long getSimulationTime()
- {
- return time.getAsLong();
- }
-
- public long nextEventTime()
- {
- if (!hasNext())
- return -1;
- return events.peek().getTiming();
- }
-
- public void reset()
- {
- events.clear();
- lastTimeUpdated = 0;
- }
-
- public void addEventAddedListener(Consumer<TimelineEvent> listener)
- {
- eventAddedListener.add(listener);
- }
-
- public void removeEventAddedListener(Consumer<TimelineEvent> listener)
- {
- eventAddedListener.remove(listener);
- }
-
- /**
- * Adds an Event to the {@link Timeline}
- *
- * @param function The {@link TimelineEventHandler} that will be executed, when the {@link InnerEvent} occurs on the timeline.
- * @param relativeTiming The amount of MI ticks in which the {@link InnerEvent} is called, starting from the current time.
- */
- public void addEvent(TimelineEventHandler function, int relativeTiming)
- {
- long timing = getSimulationTime() + relativeTiming;
- TimelineEvent event = new TimelineEvent(timing);
- events.add(new InnerEvent(function, event));
- eventAddedListener.forEach(l -> l.accept(event));
- }
-
- private class InnerEvent implements Runnable, Comparable<InnerEvent>
- {
- private final TimelineEventHandler function;
- private final TimelineEvent event;
-
- /**
- * Creates an {@link InnerEvent}
- *
- * @param function {@link TimelineEventHandler} to be executed when the {@link InnerEvent} occurs
- * @param timing Point in the MI simulation {@link Timeline}, at which the {@link InnerEvent} is executed;
- */
- InnerEvent(TimelineEventHandler function, TimelineEvent event)
- {
- this.function = function;
- this.event = event;
- }
-
- public long getTiming()
- {
- return event.getTiming();
- }
-
- @Override
- public void run()
- {
- function.handle(event);
- }
-
- @Override
- public String toString()
- {
- return event.toString();
- }
-
- @Override
- public int compareTo(InnerEvent o)
- {
- return timeCmp(getTiming(), o.getTiming());
- }
- }
-
- public static int timeCmp(long a, long b)
- {
- return Long.signum(a - b);
- }
-
- @Override
- public String toString()
- {
- return String.format("Simulation time: %s, Last update: %d, Events: %s", getSimulationTime(), lastTimeUpdated, events.toString());
- }
-
- public enum ExecutionResult
- {
- NOTHING_DONE, EXEC_UNTIL_EMPTY, EXEC_UNTIL_CONDITION, EXEC_OUT_OF_TIME
- }
-}
\ No newline at end of file