/**
 * Copyright (C) 2009 - present by OpenGamma Inc. and the OpenGamma group of companies
 *
 * Please see distribution for license.
 */
package com.opengamma.web.spring;

import com.opengamma.engine.function.CompiledFunctionDefinition;
import com.opengamma.engine.function.CompiledFunctionService;
import com.opengamma.engine.function.resolver.DefaultFunctionResolver;
import com.opengamma.engine.function.resolver.FunctionPriority;
import com.opengamma.engine.function.resolver.FunctionResolver;
import com.opengamma.financial.analytics.FilteringSummingFunction;
import com.opengamma.financial.currency.CurrencyConversionFunction;
import com.opengamma.financial.currency.CurrencyMatrixLookupFunction;
import com.opengamma.financial.currency.CurrencySeriesConversionFunction;
import com.opengamma.financial.property.DefaultPropertyFunction;
import com.opengamma.util.SingletonFactoryBean;

/**
 * Creates a FunctionResolver for the demo, prioritizing the functions
 */
@SuppressWarnings("deprecation")
public class DemoFunctionResolverFactoryBean extends SingletonFactoryBean<FunctionResolver> {

  private CompiledFunctionService _functionCompilationService;

  public void setFunctionCompilationService(final CompiledFunctionService functionCompilationService) {
    _functionCompilationService = functionCompilationService;
  }

  public CompiledFunctionService getFunctionCompilationService() {
    return _functionCompilationService;
  }

  /**
   * A default set of function priorities.
   */
  public static class Priority implements FunctionPriority {
    @Override
    public int getPriority(final CompiledFunctionDefinition function) {
      if (function instanceof CurrencyConversionFunction || function instanceof CurrencySeriesConversionFunction) {
        return Integer.MIN_VALUE;
      }
      if (function instanceof DefaultPropertyFunction) {
        final DefaultPropertyFunction defaultPropertyFunction = (DefaultPropertyFunction) function;
        if (defaultPropertyFunction.isPermitWithout()) {
          // Place below the filtering summing function priority, or the filter may never be applied.
          return -2 + defaultPropertyFunction.getPriority().getPriorityAdjust() - DefaultPropertyFunction.PriorityClass.MAX_ADJUST;
        } else {
          // All other currency injections are important; e.g. the currency constraint can't be omitted for some functions
          return Integer.MAX_VALUE + defaultPropertyFunction.getPriority().getPriorityAdjust() - DefaultPropertyFunction.PriorityClass.MAX_ADJUST;
        }
      }
      if (function instanceof FilteringSummingFunction) {
        // Anything that filters should be lower priority than a conventional summing operation that can apply
        // to all of its inputs
        return -1;
      }
      if (function instanceof CurrencyMatrixLookupFunction) {
        final CurrencyMatrixLookupFunction currencyMatrixLookupFunction = (CurrencyMatrixLookupFunction) function;
        return currencyMatrixLookupFunction.getPriority();
      }
      return 0;
    }
  }

  public static FunctionResolver createFunctionResolver(final CompiledFunctionService functionCompilationSerice) {
    return new DefaultFunctionResolver(functionCompilationSerice, new Priority());
  }

  @Override
  protected FunctionResolver createObject() {
    return createFunctionResolver(getFunctionCompilationService());
  }

}