#include <list>
#include <cassert>
#include <cstdlib>
#include <iterator>

#include "utility.h"

#include "SynTree/Statement.h"
#include "SynTree/Expression.h"
#include "SynTree/Constant.h"
#include "SynTree/Type.h"
#include "CaseRangeMutator.h"

namespace ControlStruct {
    Statement *CaseRangeMutator::mutate(ChooseStmt *chooseStmt) {
	/* There shouldn't be any `choose' statements by now, throw an exception or something. */
	throw( 0 ) ; /* FIXME */
    }

    Statement *CaseRangeMutator::mutate(SwitchStmt *switchStmt) {
	std::list< Statement * > &cases = switchStmt->get_branches();

	// a `for' would be more natural... all this contortions are because `replace' invalidates the iterator
	std::list< Statement * >::iterator i = cases.begin();
	while (  i != cases.end() ) {
	    (*i)->acceptMutator( *this );

	    if ( ! newCaseLabels.empty() ) {
		std::list< Statement * > newCases;

		// transform( newCaseLabels.begin(), newCaseLabels.end(), bnd1st( ptr_fun( ctor< CaseStmt, Label, Expression * > ) ) );

		for ( std::list< Expression * >::iterator j = newCaseLabels.begin();
		      j != newCaseLabels.end(); j++ ) {
		    std::list<Label> emptyLabels;
		    std::list< Statement *> emptyStmts;
		    newCases.push_back( new CaseStmt( emptyLabels, *j, emptyStmts ) );
		}

		if ( CaseStmt *currentCase = dynamic_cast< CaseStmt * > ( *i ) )
		    if ( ! currentCase->get_statements().empty() ) {
			CaseStmt *lastCase = dynamic_cast< CaseStmt * > ( newCases.back() );
			if ( lastCase == 0 ) { throw ( 0 ); /* FIXME */ } // something is very wrong, as I just made these, and they were all cases
			// transfer the statement block (if any) to the new list:
			lastCase->set_statements( currentCase->get_statements() );
		    }
		std::list< Statement * >::iterator j = i; advance( j, 1 );
		replace ( cases, i, newCases );
		i = j;
		newCaseLabels.clear();
	    } else
		i++;
	} // while

	return switchStmt;
    }

    Statement *CaseRangeMutator::mutate(FallthruStmt *fallthruStmt) {
	//delete fallthruStmt;
	return new NullStmt();
    }

    Statement *CaseRangeMutator::mutate(CaseStmt *caseStmt) {
	UntypedExpr *cond;
	if ( (cond = dynamic_cast< UntypedExpr * >( caseStmt->get_condition() )) != 0 ) {
	    NameExpr *nmfunc;
	    if ( (nmfunc = dynamic_cast< NameExpr *>( cond->get_function() )) != 0 ) {
		if ( nmfunc->get_name() == std::string("Range") ) {
		    assert( cond->get_args().size() == 2 );
		    std::list<Expression *>::iterator i = cond->get_args().begin();
		    Expression *lo = *i, *hi = *(++i); // "unnecessary" temporaries
		    fillRange( lo, hi);
		}
	    }
	} else if ( TupleExpr *tcond = dynamic_cast< TupleExpr * >( caseStmt->get_condition() ) ) {
	    // case list
	    assert( ! tcond->get_exprs().empty() );
	    for ( std::list< Expression * >::iterator i = tcond->get_exprs().begin(); i != tcond->get_exprs().end(); i++ )
		newCaseLabels.push_back( *i ); // do I need to clone them?
	} // if

	std::list< Statement * > &stmts = caseStmt->get_statements();
	mutateAll ( stmts, *this );

	return caseStmt;
    }

    void CaseRangeMutator::fillRange(Expression *lo, Expression *hi) {
	// generate the actual range (and check for consistency)
	Constant *c_lo, *c_hi;
	ConstantExpr *ce_lo, *ce_hi;
	ce_lo = dynamic_cast< ConstantExpr * >( lo );
	ce_hi = dynamic_cast< ConstantExpr * >( hi );

	if ( ce_lo && ce_hi ) {
	    c_lo = ce_lo->get_constant(); c_hi = ce_hi->get_constant();
	} /* else {
	     if ( ! ce_lo ) ;
	     if ( ! ce_hi ) ;
	     } */
	BasicType *ty_lo = dynamic_cast< BasicType * >( c_lo->get_type() ),
	    *ty_hi = dynamic_cast< BasicType * >( c_hi->get_type() );
    
	if ( ! ty_lo || ! ty_hi )
	    return; // one of them is not a constant

	switch ( ty_lo->get_kind() ) {
	  case BasicType::Char:
	  case BasicType::UnsignedChar:
	    switch ( ty_hi->get_kind() ){
		  case BasicType::Char:
		  case BasicType::UnsignedChar:
		    // first case, they are both printable ASCII characters represented as 'x'
		    if ( c_lo->get_value().size() == 3 && c_hi->get_value().size() == 3 ) {
			char ch_lo = (c_lo->get_value())[1], ch_hi = (c_hi->get_value())[1];

			if ( ch_lo > ch_hi ) { char t=ch_lo; ch_lo=ch_hi; ch_hi=t; }

			for ( char c = ch_lo; c <=  ch_hi; c++ ){
			    Type::Qualifiers q;
			    Constant cnst( new BasicType(q, BasicType::Char),
					   std::string("'") + c + std::string("'") );
			    newCaseLabels.push_back( new ConstantExpr( cnst ) );
			}

			return;
		    }
		    break;
		  default:
		    // error: incompatible constants
		    break;
		}
	    break;
	  case BasicType::ShortSignedInt:
	  case BasicType::ShortUnsignedInt:
	  case BasicType::SignedInt:
	  case BasicType::UnsignedInt:
	  case BasicType::LongSignedInt:
	  case BasicType::LongUnsignedInt:
	  case BasicType::LongLongSignedInt:
	  case BasicType::LongLongUnsignedInt:
	    switch ( ty_hi->get_kind() ) {
	      case BasicType::ShortSignedInt:
	      case BasicType::ShortUnsignedInt:
	      case BasicType::SignedInt:
	      case BasicType::UnsignedInt:
	      case BasicType::LongSignedInt:
	      case BasicType::LongUnsignedInt:
	      case BasicType::LongLongSignedInt:
	      case BasicType::LongLongUnsignedInt: {
		  int i_lo = atoi(c_lo->get_value().c_str()),
		      i_hi = atoi(c_hi->get_value().c_str());

		  if ( i_lo > i_hi ) { int t=i_lo; i_lo=i_hi; i_hi=t; }

		  for ( int c = i_lo; c <=  i_hi; c++ ){
		      Type::Qualifiers q;
		      Constant cnst( new BasicType(q, ty_hi->get_kind()), // figure can't hurt (used to think in positives)
				     toString< int >( c ) );
		      newCaseLabels.push_back( new ConstantExpr( cnst ) );
		  }

		  return;
	      }
	      default:
		// error: incompatible constants
		break;
	    }
	    break;
	  default:
	    break;
	} // switch

	/* End: */{ 
	    // invalid range, signal a warning (it still generates the two case labels)
	    newCaseLabels.push_back( lo );
	    newCaseLabels.push_back( hi );
	    return;
	}
    }
} // namespace ControlStruct