package edu.mit.streamjit.api;

import edu.mit.streamjit.PrimitiveWorker;
import edu.mit.streamjit.StreamElement;
import edu.mit.streamjit.StreamVisitor;
import edu.mit.streamjit.impl.common.Workers;
import java.util.List;

/**
 * see comments on Splitter
 * @author Jeffrey Bosboom <jeffreybosboom@gmail.com>
 * @since 11/7/2012
 */
public abstract class Joiner<I, O> extends PrimitiveWorker<I, O> implements StreamElement<I, O> {
	public static final int UNLIMITED = Integer.MAX_VALUE;

	@Override
	public final void visit(StreamVisitor v) {
		v.visitJoiner(this);
	}

	/**
	 * Returns the number of input channels this Joiner instance may read
	 * from, or UNLIMITED if any number >= 1 is supported.
	 * TODO: maybe this should be part of the rate handling?
	 * @return
	 */
	public abstract int supportedInputs();

	/**
	 * Returns the number of input channels connected to this joiner.
	 *
	 * This method should only be called from work(), getPeekRates() and
	 * getPopRates() or functions called from them.
	 *
	 * Implementation note: this is a JIT hook method.
	 * @return the number of output channels connected to this splitter
	 */
	protected final int inputs() {
		return Workers.getInputChannels(this).size();
	};

	/**
	 * Peeks at the item at the given position on the given input channel. The index
	 * is 0-based and moves with calls to pop(); that is, peek(i, 0) == pop(i) no
	 * matter how many times pop() is called.
	 *
	 * This method should only be called from work() or functions called from
	 * work().
	 *
	 * Implementation note: this is a JIT hook method.
	 * @param channel the index of the input channel to peek at
	 * @param position the position to peek at
	 * @return an item on the input channel
	 */
	protected final I peek(int channel, int position) {
		//TODO: check rates?
		return Workers.getInputChannels(this).get(channel).peek(position);
	};

	/**
	 * Pops an item off the given input channel.
	 *
	 * This method should only be called from work() or functions called from
	 * work().
	 *
	 * Implementation note: this is a JIT hook method.
	 * @param channel the index of the input channel to pop from
	 * @return the first item in the input channel
	 */
	protected final I pop(int channel) {
		//TODO: check rates?
		return Workers.getInputChannels(this).get(channel).pop();
	};

	/**
	 * Pushes the given item onto the output channel.
	 *
	 * This method should only be called from work() or functions called from
	 * work().
	 *
	 * Implementation note: this is a JIT hook method.
	 * @param item the item to push
	 */
	protected final void push(O item) {
		//TODO: check rates?
		Workers.getOutputChannels(this).get(0).push(item);
	};
}

@@ -1782,39 +1782,16 @@
 tion) %7B%0A
-%09%09//TODO: check rates?%0A
 %09%09return
@@ -2207,39 +2207,16 @@
 nnel) %7B%0A
-%09%09//TODO: check rates?%0A
 %09%09return
@@ -2554,31 +2554,8 @@
 ) %7B%0A
-%09%09//TODO: check rates?%0A
 %09%09Wo

remove stale TODOs, see decc3c2d