/* This file is part of the KDE project
   Copyright (C) 2003,2004 Ariya Hidayat <ariya@kde.org>
   Copyright (C) 2005 Tomas Mecir <mecirt@gmail.com>

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License.

   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
*/

#include "formula.h"
#include "functions.h"
#include "valuecalc.h"

#include <tqdict.h>
#include <tqdom.h>
#include <tqfile.h>
#include <tqvaluevector.h>

#include <kdebug.h>
#include <klocale.h>
#include <kstandarddirs.h>
#include <kstaticdeleter.h>

#include "kspread_factory.h"

namespace KSpread
{

class Function::Private
{
public:
  TQString name;
  FunctionPtr ptr;
  int paramMin, paramMax;
  bool acceptArray;
  bool ne;   // need FunctionExtra* when called ?
};

class FunctionRepository::Private
{
public:
  TQDict<Function> functions;
  TQDict<FunctionDescription> funcs;
};

} // namespace KSpread


using namespace KSpread;

Function::Function( const TQString& name, FunctionPtr ptr )
{
  d = new Private;
  d->name = name;
  d->ptr = ptr;
  d->acceptArray = false;
  d->paramMin = 1;
  d->paramMax = 1;
  d->ne = false;
}

Function::~Function()
{
  delete d;
}

TQString Function::name() const
{
  return d->name;
}

void Function::setParamCount (int min, int max)
{
  d->paramMin = min;
  d->paramMax = (max == 0) ? min : max;
}

bool Function::paramCountOkay (int count)
{
  // less than needed
  if (count < d->paramMin) return false;
  // no upper limit
  if (d->paramMax == -1) return true;
  // more than needed
  if (count > d->paramMax) return false;
  // okay otherwise
  return true;
}

void Function::setAcceptArray (bool accept) {
  d->acceptArray = accept;
}

bool Function::needsExtra () {
  return d->ne;
}
void Function::setNeedsExtra (bool extra) {
  d->ne = extra;
}

Value Function::exec (valVector args, ValueCalc *calc, FuncExtra *extra)
{
  // check number of parameters
  if (!paramCountOkay (args.count()))
    return Value::errorVALUE();

  // do we need to perform array expansion ?
  bool mustExpandArray = false;
  if (!d->acceptArray)
    for (unsigned int i = 0; i < args.count(); ++i) {
      if (args[i].isArray())
        mustExpandArray = true;
    }

  if( !d->ptr ) return Value::errorVALUE();
  
  // perform the actual array expansion if need be
  
  if (mustExpandArray) {
    // compute number of rows/cols of the result
    int rows = 0;
    int cols = 0;
    for (unsigned int i = 0; i < args.count(); ++i) {
      int x = (args[i].type() == Value::Array) ? args[i].rows() : 1;
      if (x > rows) rows = x;
      x = (args[i].type() == Value::Array) ? args[i].columns() : 1;
      if (x > cols) cols = x;
    }
    // allocate the resulting array
    Value res (cols, rows);
    // perform the actual computation for each element of the array
    for (int row = 0; row < rows; ++row)
      for (int col = 0; col < cols; ++col) {
        // fill in the parameter vector
        valVector vals (args.count());
        for (unsigned int i = 0; i < args.count(); ++i) {
          int r = args[i].rows();
          int c = args[i].columns();
          vals[i] = args[i].isArray() ?
              args[i].element (col % c, row % r): args[i];
        }
        
        // execute the function on each element
        res.setElement (col, row, exec (vals, calc, extra));
      }
    return res;
  }
  else
    // call the function
    return (*d->ptr) (args, calc, extra);
}


// these are defined in kspread_function_*.cc
void RegisterConversionFunctions();
void RegisterDatabaseFunctions();
void RegisterDateTimeFunctions();
void RegisterEngineeringFunctions();
void RegisterFinancialFunctions();
void RegisterInformationFunctions();
void RegisterLogicFunctions();
void RegisterMathFunctions();
void RegisterReferenceFunctions();
void RegisterStatisticalFunctions();
void RegisterTextFunctions();
void RegisterTrigFunctions();


static KStaticDeleter<FunctionRepository> fr_sd;
FunctionRepository* FunctionRepository::s_self = 0;

FunctionRepository* FunctionRepository::self()
{
  if( !s_self )
  {
    kdDebug() << "Creating function repository" << endl;
  
    fr_sd.setObject( s_self, new FunctionRepository() );
  
    kdDebug() << "Registering functions" << endl;
    
    // register all existing functions
    RegisterConversionFunctions();
    RegisterDatabaseFunctions();
    RegisterDateTimeFunctions();
    RegisterEngineeringFunctions();
    RegisterFinancialFunctions();
    RegisterInformationFunctions();
    RegisterLogicFunctions();
    RegisterMathFunctions();
    RegisterReferenceFunctions();
    RegisterStatisticalFunctions();
    RegisterTextFunctions();
    RegisterTrigFunctions();
  
    kdDebug() << "Functions registered, loading descriptions" << endl;
  
    // find all XML description files
    TQStringList files = Factory::global()->dirs()->findAllResources
        ("extensions", "*.xml", TRUE);
    
    // load desc/help from XML file
    for( TQStringList::Iterator it = files.begin(); it != files.end(); ++it )
      s_self->loadFile (*it);
  
    kdDebug() << "All ok, repository ready" << endl;

  }    
  return s_self;
}

FunctionRepository::FunctionRepository()
{
  d = new Private;
  
  d->functions.setAutoDelete( true );
  d->funcs.setAutoDelete( true );
}

FunctionRepository::~FunctionRepository()
{
  delete d;
  s_self = 0;
}

void FunctionRepository::add( Function* function )
{
  if( !function ) return;
  d->functions.insert( function->name().upper(), function );
}

Function *FunctionRepository::function (const TQString& name)
{
  return d->functions.find (name.upper());
}

FunctionDescription *FunctionRepository::functionInfo (const TQString& name)
{
  return d->funcs.find (name.upper());
}

// returns names of function in certain group
TQStringList FunctionRepository::functionNames( const TQString& group )
{
  TQStringList lst;

  TQDictIterator<FunctionDescription> it (d->funcs);
  for(; it.current(); ++it) {
    if (group.isNull() || (it.current()->group() == group))
      lst.append (it.current()->name());
  }
  
  lst.sort();
  return lst;
}

void FunctionRepository::loadFile (const TQString& filename)
{
  TQFile file (filename);
  if (!file.open (IO_ReadOnly))
    return;

  TQDomDocument doc;
  doc.setContent( &file );
  file.close();

  TQString group = "";

  TQDomNode n = doc.documentElement().firstChild();
  for (; !n.isNull(); n = n.nextSibling())
  {
    if (!n.isElement())
      continue;
    TQDomElement e = n.toElement();
    if (e.tagName() == "Group")
    {
      group = i18n (e.namedItem ("GroupName").toElement().text().utf8());
      m_groups.append( group );
      m_groups.sort();
    
      TQDomNode n2 = e.firstChild();
      for (; !n2.isNull(); n2 = n2.nextSibling())
      {
        if (!n2.isElement())
          continue;
        TQDomElement e2 = n2.toElement();
        if (e2.tagName() == "Function")
        {
          FunctionDescription* desc = new FunctionDescription( e2 );
          desc->setGroup (group);
          if (d->functions.find (desc->name()))
            d->funcs.insert (desc->name(), desc);
        }
      }
      group = "";
    }
  }
}

// ------------------------------------------------------------

static ParameterType toType( const TQString& type )
{
  if ( type == "Boolean" )
    return KSpread_Boolean;
  if ( type == "Int" )
    return KSpread_Int;
  if ( type == "String" )
    return KSpread_String;
  if ( type == "Any" )
    return KSpread_Any;

  return KSpread_Float;
}

static TQString toString (ParameterType type, bool range = FALSE)
{
  if ( !range )
  {
    switch(type) {
      case KSpread_String:
        return i18n("Text");
      case KSpread_Int:
        return i18n("Whole number (like 1, 132, 2344)");
      case KSpread_Boolean:
        return i18n("A truth value (TRUE or FALSE)" );
      case KSpread_Float:
        return i18n("A floating point value (like 1.3, 0.343, 253 )" );
      case KSpread_Any:
        return i18n("Any kind of value");
    }
  }
  else
  {
    switch(type) {
      case KSpread_String:
        return i18n("A range of strings");
      case KSpread_Int:
        return i18n("A range of whole numbers (like 1, 132, 2344)");
      case KSpread_Boolean:
        return i18n("A range of truth values (TRUE or FALSE)" );
      case KSpread_Float:
        return i18n("A range of floating point values (like 1.3, 0.343, 253 )" );
      case KSpread_Any:
        return i18n("A range of any kind of values");
    }
  }

  return TQString();
}

FunctionParameter::FunctionParameter()
{
  m_type = KSpread_Float;
  m_range = FALSE;
}

FunctionParameter::FunctionParameter (const FunctionParameter& param)
{
  m_help = param.m_help;
  m_type = param.m_type;
  m_range = param.m_range;
}

FunctionParameter::FunctionParameter (const TQDomElement& element)
{
  m_type  = KSpread_Float;
  m_range = FALSE;

  TQDomNode n = element.firstChild();
  for( ; !n.isNull(); n = n.nextSibling() )
    if ( n.isElement() )
    {
      TQDomElement e = n.toElement();
      if ( e.tagName() == "Comment" )
        m_help = i18n( e.text().utf8() );
      else if ( e.tagName() == "Type" )
      {
        m_type = toType( e.text() );
        if ( e.hasAttribute( "range" ))
        {
          if (e.attribute("range").lower() == "true")
            m_range = TRUE;
        }
      }
    }
}

FunctionDescription::FunctionDescription()
{
  m_type = KSpread_Float;
}

FunctionDescription::FunctionDescription (const TQDomElement& element)
{
  TQDomNode n = element.firstChild();
  for( ; !n.isNull(); n = n.nextSibling() )
  {
    if (!n.isElement())
      continue;
    TQDomElement e = n.toElement();
    if ( e.tagName() == "Name" )
      m_name = e.text();
    else if ( e.tagName() == "Type" )
      m_type = toType( e.text() );
    else if ( e.tagName() == "Parameter" )
      m_params.append (FunctionParameter (e));
    else if ( e.tagName() == "Help" )
    {
      TQDomNode n2 = e.firstChild();
      for( ; !n2.isNull(); n2 = n2.nextSibling() )
      {
        if (!n2.isElement())
          continue;
        TQDomElement e2 = n2.toElement();
        if ( e2.tagName() == "Text" )
          m_help.append ( i18n( e2.text().utf8() ) );
        else if ( e2.tagName() == "Syntax" )
          m_syntax.append( i18n( e2.text().utf8() ) );
        else if ( e2.tagName() == "Example" )
          m_examples.append( i18n( e2.text().utf8() ) );
        else if ( e2.tagName() == "Related" )
          m_related.append( i18n( e2.text().utf8() ) );
      }
    }
  }
}

FunctionDescription::FunctionDescription( const FunctionDescription& desc )
{
  m_examples = desc.m_examples;
  m_related = desc.m_related;
  m_syntax = desc.m_syntax;
  m_help = desc.m_help;
  m_name = desc.m_name;
  m_type = desc.m_type;
}

TQString FunctionDescription::toTQML() const
{
  TQString text( "<qt><h1>" );
  text += name();
  text += "</h1>";

  if( !m_help.isEmpty() )
  {
    text += i18n("<p>");
    TQStringList::ConstIterator it = m_help.begin();
    for( ; it != m_help.end(); ++it )
    {
      text += *it;
      text += "<p>";
    }
    text += "</p>";
  }

  text += i18n("<p><b>Return type: </b>");
  text += toString( type() );
  text += "</p>";

  if ( !m_syntax.isEmpty() )
  {
    text += i18n("<h2>Syntax</h2><ul>");
    TQStringList::ConstIterator it = m_syntax.begin();
    for( ; it != m_syntax.end(); ++it )
    {
      text += "<li>";
      text += *it;
    }
    text += "</ul>";
  }

  if ( !m_params.isEmpty() )
  {
    text += i18n("<h2>Parameters</h2><ul>");
    TQValueList<FunctionParameter>::ConstIterator it = m_params.begin();
    for( ; it != m_params.end(); ++it )
    {
      text += i18n("<li><b>Comment:</b> ");
      text += (*it).helpText();
      text += i18n("<br><b>Type:</b> ");
      text += toString( (*it).type(), (*it).hasRange() );
    }
    text += "</ul>";
  }

  if ( !m_examples.isEmpty() )
  {
    text += i18n("<h2>Examples</h2><ul>");
    TQStringList::ConstIterator it = m_examples.begin();
    for( ; it != m_examples.end(); ++it )
    {
      text += "<li>";
      text += *it;
    }
    text += "</ul>";
  }

  if ( !m_related.isEmpty() )
  {
    text += i18n("<h2>Related Functions</h2><ul>");
    TQStringList::ConstIterator it = m_related.begin();
    for( ; it != m_related.end(); ++it )
    {
      text += "<li>";
      text += "<a href=\"" + *it + "\">";
      text += *it;
      text += "</a>";
    }
    text += "</ul>";
  }

  text += "</qt>";
  return text;
}