/*============================================================================
  CMake - Cross Platform Makefile Generator
  Copyright 2012 Stephen Kelly <steveire@gmail.com>

  Distributed under the OSI-approved BSD License (the "License");
  see accompanying file Copyright.txt for details.

  This software is distributed WITHOUT ANY WARRANTY; without even the
  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the License for more information.
============================================================================*/
#include "cmGeneratorExpressionEvaluator.h"

#include "cmAlgorithms.h"
#include "cmGeneratorExpression.h"
#include "cmGeneratorExpressionDAGChecker.h"
#include "cmGeneratorExpressionParser.h"
#include "cmGlobalGenerator.h"
#include "cmLocalGenerator.h"
#include "cmMakefile.h"
#include "cmSourceFile.h"

#include <cmsys/String.h>

#include <assert.h>
#include <errno.h>

#include "cmGeneratorExpressionNode.h"

GeneratorExpressionContent::GeneratorExpressionContent(
                                                    const char *startContent,
                                                    size_t length)
  : StartContent(startContent), ContentLength(length)
{

}

std::string GeneratorExpressionContent::GetOriginalExpression() const
{
  return std::string(this->StartContent, this->ContentLength);
}

std::string GeneratorExpressionContent::ProcessArbitraryContent(
    const cmGeneratorExpressionNode *node,
    const std::string &identifier,
    cmGeneratorExpressionContext *context,
    cmGeneratorExpressionDAGChecker *dagChecker,
    std::vector<std::vector<cmGeneratorExpressionEvaluator*> >::const_iterator
    pit) const
{
  std::string result;

  const
  std::vector<std::vector<cmGeneratorExpressionEvaluator*> >::const_iterator
                                      pend = this->ParamChildren.end();
  for ( ; pit != pend; ++pit)
    {
    std::vector<cmGeneratorExpressionEvaluator*>::const_iterator it
                                                            = pit->begin();
    const std::vector<cmGeneratorExpressionEvaluator*>::const_iterator end
                                                              = pit->end();
    for ( ; it != end; ++it)
      {
      if (node->RequiresLiteralInput())
        {
        if ((*it)->GetType() != cmGeneratorExpressionEvaluator::Text)
          {
          reportError(context, this->GetOriginalExpression(),
                "$<" + identifier + "> expression requires literal input.");
          return std::string();
          }
        }
      result += (*it)->Evaluate(context, dagChecker);
      if (context->HadError)
        {
        return std::string();
        }
      }
      if ((pit + 1) != pend)
        {
        result += ",";
        }
    }
  if (node->RequiresLiteralInput())
    {
    std::vector<std::string> parameters;
    parameters.push_back(result);
    return node->Evaluate(parameters, context, this, dagChecker);
    }
  return result;
}

std::string GeneratorExpressionContent::Evaluate(
                            cmGeneratorExpressionContext *context,
                            cmGeneratorExpressionDAGChecker *dagChecker) const
{
  std::string identifier;
  {
  std::vector<cmGeneratorExpressionEvaluator*>::const_iterator it
                                          = this->IdentifierChildren.begin();
  const std::vector<cmGeneratorExpressionEvaluator*>::const_iterator end
                                          = this->IdentifierChildren.end();
  for ( ; it != end; ++it)
    {
    identifier += (*it)->Evaluate(context, dagChecker);
    if (context->HadError)
      {
      return std::string();
      }
    }
  }

  const cmGeneratorExpressionNode *node =
      cmGeneratorExpressionNode::GetNode(identifier);

  if (!node)
    {
    reportError(context, this->GetOriginalExpression(),
              "Expression did not evaluate to a known generator expression");
    return std::string();
    }

  if (!node->GeneratesContent())
    {
    if (node->NumExpectedParameters() == 1
        && node->AcceptsArbitraryContentParameter())
      {
      if (this->ParamChildren.empty())
        {
        reportError(context, this->GetOriginalExpression(),
                  "$<" + identifier + "> expression requires a parameter.");
        }
      }
    else
      {
      std::vector<std::string> parameters;
      this->EvaluateParameters(node, identifier, context, dagChecker,
                               parameters);
      }
    return std::string();
    }

  std::vector<std::string> parameters;
  this->EvaluateParameters(node, identifier, context, dagChecker, parameters);
  if (context->HadError)
    {
    return std::string();
    }

  return node->Evaluate(parameters, context, this, dagChecker);
}

std::string GeneratorExpressionContent::EvaluateParameters(
                                const cmGeneratorExpressionNode *node,
                                const std::string &identifier,
                                cmGeneratorExpressionContext *context,
                                cmGeneratorExpressionDAGChecker *dagChecker,
                                std::vector<std::string> &parameters) const
{
  const int numExpected = node->NumExpectedParameters();
  {
  std::vector<std::vector<cmGeneratorExpressionEvaluator*> >::const_iterator
                                        pit = this->ParamChildren.begin();
  const
  std::vector<std::vector<cmGeneratorExpressionEvaluator*> >::const_iterator
                                        pend = this->ParamChildren.end();
  const bool acceptsArbitraryContent
                                  = node->AcceptsArbitraryContentParameter();
  int counter = 1;
  for ( ; pit != pend; ++pit, ++counter)
    {
    if (acceptsArbitraryContent && counter == numExpected)
      {
      std::string lastParam = this->ProcessArbitraryContent(node, identifier,
                                                            context,
                                                            dagChecker,
                                                            pit);
      parameters.push_back(lastParam);
      return std::string();
      }
    else
      {
      std::string parameter;
      std::vector<cmGeneratorExpressionEvaluator*>::const_iterator it =
                                                                pit->begin();
      const std::vector<cmGeneratorExpressionEvaluator*>::const_iterator end =
                                                                pit->end();
      for ( ; it != end; ++it)
        {
        parameter += (*it)->Evaluate(context, dagChecker);
        if (context->HadError)
          {
          return std::string();
          }
        }
      parameters.push_back(parameter);
      }
    }
  }

  if ((numExpected > cmGeneratorExpressionNode::DynamicParameters
      && (unsigned int)numExpected != parameters.size()))
    {
    if (numExpected == 0)
      {
      reportError(context, this->GetOriginalExpression(),
                  "$<" + identifier + "> expression requires no parameters.");
      }
    else if (numExpected == 1)
      {
      reportError(context, this->GetOriginalExpression(),
                  "$<" + identifier + "> expression requires "
                  "exactly one parameter.");
      }
    else
      {
      std::ostringstream e;
      e << "$<" + identifier + "> expression requires "
        << numExpected
        << " comma separated parameters, but got "
        << parameters.size() << " instead.";
      reportError(context, this->GetOriginalExpression(), e.str());
      }
    return std::string();
    }

  if (numExpected == cmGeneratorExpressionNode::OneOrMoreParameters
      && parameters.empty())
    {
    reportError(context, this->GetOriginalExpression(), "$<" + identifier
                      + "> expression requires at least one parameter.");
    }
  if (numExpected == cmGeneratorExpressionNode::OneOrZeroParameters
      && parameters.size() > 1)
    {
    reportError(context, this->GetOriginalExpression(), "$<" + identifier
                      + "> expression requires one or zero parameters.");
    }
  return std::string();
}

GeneratorExpressionContent::~GeneratorExpressionContent()
{
  cmDeleteAll(this->IdentifierChildren);
  std::for_each(this->ParamChildren.begin(), this->ParamChildren.end(),
                cmDeleteAll<std::vector<cmGeneratorExpressionEvaluator*> >);
}
