/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.sysds.runtime.instructions.fed;

import org.apache.commons.lang3.tuple.Pair;
import org.apache.sysds.api.DMLScript;
import org.apache.sysds.common.Types.ExecMode;
import org.apache.sysds.hops.OptimizerUtils;
import org.apache.sysds.runtime.controlprogram.caching.CacheableData;
import org.apache.sysds.runtime.controlprogram.context.ExecutionContext;
import org.apache.sysds.runtime.instructions.cp.CPOperand;
import org.apache.sysds.runtime.lineage.LineageItem;
import org.apache.sysds.runtime.lineage.LineageItemUtils;
import org.apache.sysds.runtime.lineage.LineageTraceable;
import org.apache.sysds.runtime.matrix.data.MatrixBlock;
import org.apache.sysds.runtime.matrix.operators.Operator;

public abstract class ComputationFEDInstruction extends FEDInstruction implements LineageTraceable {
	
	public final CPOperand output;
	public final CPOperand input1, input2, input3;
	
	protected ComputationFEDInstruction(FEDType type, Operator op, CPOperand in1, CPOperand in2, CPOperand out,
			String opcode,
			String istr) {
		super(type, op, opcode, istr);
		input1 = in1;
		input2 = in2;
		input3 = null;
		output = out;
	}
	
	protected ComputationFEDInstruction(FEDType type, Operator op, CPOperand in1, CPOperand in2, CPOperand in3,
			CPOperand out,
			String opcode, String istr) {
		super(type, op, opcode, istr);
		input1 = in1;
		input2 = in2;
		input3 = in3;
		output = out;
	}
	
	public String getOutputVariableName() {
		return output.getName();
	}
	
	protected boolean checkGuardedRepresentationChange(MatrixBlock in1, MatrixBlock out) {
		return checkGuardedRepresentationChange(in1, null, out);
	}
	
	protected boolean checkGuardedRepresentationChange(MatrixBlock in1, MatrixBlock in2, MatrixBlock out) {
		if( DMLScript.getGlobalExecMode() == ExecMode.SINGLE_NODE
				&& !CacheableData.isCachingActive() )
			return true;
		double memIn1 = (in1 != null) ? in1.getInMemorySize() : 0;
		double memIn2 = (in2 != null) ? in2.getInMemorySize() : 0;
		double memReq = out.isInSparseFormat() ?
				MatrixBlock.estimateSizeDenseInMemory(out.getNumRows(), out.getNumColumns()) :
				MatrixBlock.estimateSizeSparseInMemory(out.getNumRows(), out.getNumColumns(), out.getSparsity());
		//guarded if mem requirements smaller than input sizes
		return (memReq < memIn1 + memIn2
				+ OptimizerUtils.SAFE_REP_CHANGE_THRES); //8MB
	}
	
	@Override
	public Pair<String, LineageItem> getLineageItem(ExecutionContext ec) {
		return Pair.of(output.getName(), new LineageItem(getOpcode(),
			LineageItemUtils.getLineage(ec, input1, input2, input3)));
	}
}