/*
 * Copyright 2009 Google Inc.
 *
 * Licensed 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 com.google.template.soy.basicfunctions;

import com.google.common.collect.ImmutableSet;
import com.google.template.soy.data.SoyValue;
import com.google.template.soy.data.restricted.FloatData;
import com.google.template.soy.data.restricted.IntegerData;
import com.google.template.soy.data.restricted.NumberData;
import com.google.template.soy.jssrc.restricted.JsExpr;
import com.google.template.soy.jssrc.restricted.SoyJsSrcFunction;
import com.google.template.soy.pysrc.restricted.PyExpr;
import com.google.template.soy.pysrc.restricted.PyFunctionExprBuilder;
import com.google.template.soy.pysrc.restricted.SoyPySrcFunction;
import com.google.template.soy.shared.restricted.SoyJavaFunction;
import com.google.template.soy.shared.restricted.SoyPureFunction;

import java.util.List;
import java.util.Set;

import javax.inject.Inject;
import javax.inject.Singleton;

/**
 * Soy function that takes the min of two numbers.
 *
 */
@Singleton
@SoyPureFunction
public final class MinFunction implements SoyJavaFunction, SoyJsSrcFunction, SoyPySrcFunction {


  @Inject
  MinFunction() {}


  @Override public String getName() {
    return "min";
  }

  @Override public Set<Integer> getValidArgsSizes() {
    return ImmutableSet.of(2);
  }

  @Override public SoyValue computeForJava(List<SoyValue> args) {
    SoyValue arg0 = args.get(0);
    SoyValue arg1 = args.get(1);

    return min(arg0, arg1);
  }

  /** Returns the numeric minimum of the two arguments. */
  public static NumberData min(SoyValue arg0, SoyValue arg1) {
    if (arg0 instanceof IntegerData && arg1 instanceof IntegerData) {
      return IntegerData.forValue(Math.min(arg0.longValue(), arg1.longValue()));
    } else {
      return FloatData.forValue(Math.min(arg0.numberValue(), arg1.numberValue()));
    }
  }

  @Override public JsExpr computeForJsSrc(List<JsExpr> args) {
    JsExpr arg0 = args.get(0);
    JsExpr arg1 = args.get(1);

    return new JsExpr(
        "Math.min(" + arg0.getText() + ", " + arg1.getText() + ")", Integer.MAX_VALUE);
  }

  @Override public PyExpr computeForPySrc(List<PyExpr> args) {
    PyExpr arg0 = args.get(0);
    PyExpr arg1 = args.get(1);

    PyFunctionExprBuilder fnBuilder = new PyFunctionExprBuilder("min");
    return fnBuilder.addArg(arg0).addArg(arg1).asPyExpr();
  }
}