/**CFile****************************************************************

  FileName    [pdrCnf.c]

  SystemName  [ABC: Logic synthesis and verification system.]

  PackageName [Property driven reachability.]

  Synopsis    [CNF computation on demand.]

  Author      [Alan Mishchenko]
  
  Affiliation [UC Berkeley]

  Date        [Ver. 1.0. Started - November 20, 2010.]

  Revision    [$Id: pdrCnf.c,v 1.00 2010/11/20 00:00:00 alanmi Exp $]

***********************************************************************/

#include "pdrInt.h"

ABC_NAMESPACE_IMPL_START


////////////////////////////////////////////////////////////////////////
///                        DECLARATIONS                              ///
////////////////////////////////////////////////////////////////////////

/*
    The CNF (p->pCnf2) is expressed in terms of object IDs.
    Each node in the CNF is marked if it has clauses (p->pCnf2->pObj2Count[Id] > 0).
    Each node in the CNF has the first clause (p->pCnf2->pObj2Clause) 
    and the number of clauses (p->pCnf2->pObj2Count).
    Each node used in a CNF of any timeframe has its SAT var recorded.
    Each frame has a reserve mapping of SAT variables into ObjIds.
*/

////////////////////////////////////////////////////////////////////////
///                     FUNCTION DEFINITIONS                         ///
////////////////////////////////////////////////////////////////////////

/**Function*************************************************************

  Synopsis    [Returns SAT variable of the given object.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
static inline int Pdr_ObjSatVar1( Pdr_Man_t * p, int k, Aig_Obj_t * pObj )
{
    return p->pCnf1->pVarNums[ Aig_ObjId(pObj) ];
}

/**Function*************************************************************

  Synopsis    [Returns SAT variable of the given object.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
//#define USE_PG
#ifdef USE_PG
static inline int Pdr_ObjSatVar2FindOrAdd( Pdr_Man_t * p, int k, Aig_Obj_t * pObj )
{ 
    Vec_Int_t * vId2Vars = p->pvId2Vars + Aig_ObjId(pObj);
    assert( p->pCnf2->pObj2Count[Aig_ObjId(pObj)] >= 0 );
    if ( Vec_IntSize(vId2Vars) == 0 )
        Vec_IntGrow(vId2Vars, 2 * k + 1);
    if ( Vec_IntGetEntry(vId2Vars, k) == 0 )
    {
        sat_solver * pSat = Pdr_ManSolver(p, k);
        Vec_Int_t * vVar2Ids = (Vec_Int_t *)Vec_PtrEntry(&p->vVar2Ids, k);
        int iVarNew = Vec_IntSize( vVar2Ids );
        assert( iVarNew > 0 );
        Vec_IntPush( vVar2Ids, Aig_ObjId(pObj) );
        Vec_IntWriteEntry( vId2Vars, k, iVarNew << 2 );
        sat_solver_setnvars( pSat, iVarNew + 1 );
        if ( k == 0 && Saig_ObjIsLo(p->pAig, pObj) ) // initialize the register output
        {
            int Lit = toLitCond( iVarNew, 1 );
            int RetValue = sat_solver_addclause( pSat, &Lit, &Lit + 1 );
            assert( RetValue == 1 );
            (void) RetValue;
            sat_solver_compress( pSat );
        }
    }
    return Vec_IntEntry( vId2Vars, k );
}
int Pdr_ObjSatVar2( Pdr_Man_t * p, int k, Aig_Obj_t * pObj, int Level, int Pol )
{
    Vec_Int_t * vLits;
    sat_solver * pSat;
    Vec_Int_t * vVar2Ids = (Vec_Int_t *)Vec_PtrEntry(&p->vVar2Ids, k);
    int nVarCount = Vec_IntSize(vVar2Ids);
    int iVarThis  = Pdr_ObjSatVar2FindOrAdd( p, k, pObj );
    int * pLit, i, iVar, iClaBeg, iClaEnd, RetValue;
    int PolPres = (iVarThis & 3);
    iVarThis >>= 2;
    if ( Aig_ObjIsCi(pObj) )
        return iVarThis;
//    Pol = 3;
//    if ( nVarCount != Vec_IntSize(vVar2Ids) || (Pol & ~PolPres) )
    if ( (Pol & ~PolPres) )
    {
        *Vec_IntEntryP( p->pvId2Vars + Aig_ObjId(pObj), k ) |= Pol;
        iClaBeg = p->pCnf2->pObj2Clause[Aig_ObjId(pObj)];
        iClaEnd = iClaBeg + p->pCnf2->pObj2Count[Aig_ObjId(pObj)];
        assert( iClaBeg < iClaEnd );
/*
        if ( (Pol & ~PolPres) != 3 )
        for ( i = iFirstClause; i < iFirstClause + nClauses; i++ )
        {
            printf( "Clause %5d : ", i );
            for ( iVar = 0; iVar < 4; iVar++ )
                printf( "%d ", ((unsigned)p->pCnf2->pClaPols[i] >> (2*iVar)) & 3 );
            printf( "  " );
            for ( pLit = p->pCnf2->pClauses[i]; pLit < p->pCnf2->pClauses[i+1]; pLit++ )
                printf( "%6d ", *pLit );
            printf( "\n" );
        }
*/
        pSat = Pdr_ManSolver(p, k);
        vLits = Vec_WecEntry( p->vVLits, Level );
        if ( (Pol & ~PolPres) == 3 )
        {
            assert( nVarCount + 1 == Vec_IntSize(vVar2Ids) );
            for ( i = iClaBeg; i < iClaEnd; i++ )
            {
                Vec_IntClear( vLits );
                Vec_IntPush( vLits, toLitCond( iVarThis, lit_sign(p->pCnf2->pClauses[i][0]) ) );
                for ( pLit = p->pCnf2->pClauses[i]+1; pLit < p->pCnf2->pClauses[i+1]; pLit++ )
                {
                    iVar = Pdr_ObjSatVar2( p, k, Aig_ManObj(p->pAig, lit_var(*pLit)), Level+1, 3 );
                    Vec_IntPush( vLits, toLitCond( iVar, lit_sign(*pLit) ) );
                }
                RetValue = sat_solver_addclause( pSat, Vec_IntArray(vLits), Vec_IntArray(vLits)+Vec_IntSize(vLits) );
                assert( RetValue );
                (void) RetValue;
            }
        }
        else // if ( (Pol & ~PolPres) == 2 || (Pol & ~PolPres) == 1 ) // write pos/neg polarity
        {
            assert( (Pol & ~PolPres) );
            for ( i = iClaBeg; i < iClaEnd; i++ )
            if ( 2 - !Abc_LitIsCompl(p->pCnf2->pClauses[i][0]) == (Pol & ~PolPres) ) // taking opposite literal
            {
                Vec_IntClear( vLits );
                Vec_IntPush( vLits, toLitCond( iVarThis, Abc_LitIsCompl(p->pCnf2->pClauses[i][0]) ) );
                for ( pLit = p->pCnf2->pClauses[i]+1; pLit < p->pCnf2->pClauses[i+1]; pLit++ )
                {
                    iVar = Pdr_ObjSatVar2( p, k, Aig_ManObj(p->pAig, lit_var(*pLit)), Level+1, ((unsigned)p->pCnf2->pClaPols[i] >> (2*(pLit-p->pCnf2->pClauses[i]-1))) & 3 );
                    Vec_IntPush( vLits, toLitCond( iVar, lit_sign(*pLit) ) );
                }
                RetValue = sat_solver_addclause( pSat, Vec_IntArray(vLits), Vec_IntArray(vLits)+Vec_IntSize(vLits) );
                assert( RetValue );
                (void) RetValue;
            }
        }
    }
    return iVarThis;
}

#else
static inline int Pdr_ObjSatVar2FindOrAdd( Pdr_Man_t * p, int k, Aig_Obj_t * pObj, int * pfNewVar )
{ 
    Vec_Int_t * vId2Vars = p->pvId2Vars + Aig_ObjId(pObj);
    assert( p->pCnf2->pObj2Count[Aig_ObjId(pObj)] >= 0 );
    if ( Vec_IntSize(vId2Vars) == 0 )
        Vec_IntGrow(vId2Vars, 2 * k + 1);
    if ( Vec_IntGetEntry(vId2Vars, k) == 0 )
    {
        sat_solver * pSat = Pdr_ManSolver(p, k);
        Vec_Int_t * vVar2Ids = (Vec_Int_t *)Vec_PtrEntry(&p->vVar2Ids, k);
        int iVarNew = Vec_IntSize( vVar2Ids );
        assert( iVarNew > 0 );
        Vec_IntPush( vVar2Ids, Aig_ObjId(pObj) );
        Vec_IntWriteEntry( vId2Vars, k, iVarNew );
        sat_solver_setnvars( pSat, iVarNew + 1 );
        if ( k == 0 && Saig_ObjIsLo(p->pAig, pObj) ) // initialize the register output
        {
            int Lit = toLitCond( iVarNew, 1 );
            int RetValue = sat_solver_addclause( pSat, &Lit, &Lit + 1 );
            assert( RetValue == 1 );
            (void) RetValue;
            sat_solver_compress( pSat );
        }
        *pfNewVar = 1;
    }
    return Vec_IntEntry( vId2Vars, k );
}
int Pdr_ObjSatVar2( Pdr_Man_t * p, int k, Aig_Obj_t * pObj, int Level, int Pol )
{
    Vec_Int_t * vLits;
    sat_solver * pSat;
    int fNewVar = 0, iVarThis  = Pdr_ObjSatVar2FindOrAdd( p, k, pObj, &fNewVar );
    int * pLit, i, iVar, iClaBeg, iClaEnd, RetValue;
    if ( Aig_ObjIsCi(pObj) || !fNewVar )
        return iVarThis;
    iClaBeg = p->pCnf2->pObj2Clause[Aig_ObjId(pObj)];
    iClaEnd = iClaBeg + p->pCnf2->pObj2Count[Aig_ObjId(pObj)];
    assert( iClaBeg < iClaEnd );
    pSat = Pdr_ManSolver(p, k);
    vLits = Vec_WecEntry( p->vVLits, Level );
    for ( i = iClaBeg; i < iClaEnd; i++ )
    {
        Vec_IntClear( vLits );
        Vec_IntPush( vLits, toLitCond( iVarThis, lit_sign(p->pCnf2->pClauses[i][0]) ) );
        for ( pLit = p->pCnf2->pClauses[i]+1; pLit < p->pCnf2->pClauses[i+1]; pLit++ )
        {
            iVar = Pdr_ObjSatVar2( p, k, Aig_ManObj(p->pAig, lit_var(*pLit)), Level+1, Pol );
            Vec_IntPush( vLits, toLitCond( iVar, lit_sign(*pLit) ) );
        }
        RetValue = sat_solver_addclause( pSat, Vec_IntArray(vLits), Vec_IntArray(vLits)+Vec_IntSize(vLits) );
        assert( RetValue );
        (void) RetValue;
    }
    return iVarThis;
}
#endif

/**Function*************************************************************

  Synopsis    [Returns SAT variable of the given object.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
int Pdr_ObjSatVar( Pdr_Man_t * p, int k, int Pol, Aig_Obj_t * pObj )
{
    if ( p->pPars->fMonoCnf )
        return Pdr_ObjSatVar1( p, k, pObj );
    else
        return Pdr_ObjSatVar2( p, k, pObj, 0, Pol );
}


/**Function*************************************************************

  Synopsis    [Returns register number for the given SAT variable.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
static inline int Pdr_ObjRegNum1( Pdr_Man_t * p, int k, int iSatVar )
{
    int RegId;
    assert( iSatVar >= 0 );
    // consider the case of auxiliary variable
    if ( iSatVar >= p->pCnf1->nVars )
        return -1;
    // consider the case of register output
    RegId = Vec_IntEntry( p->vVar2Reg, iSatVar );
    assert( RegId >= 0 && RegId < Aig_ManRegNum(p->pAig) );
    return RegId;
}

/**Function*************************************************************

  Synopsis    [Returns register number for the given SAT variable.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
static inline int Pdr_ObjRegNum2( Pdr_Man_t * p, int k, int iSatVar )
{
    Aig_Obj_t * pObj;
    int ObjId;
    Vec_Int_t * vVar2Ids = (Vec_Int_t *)Vec_PtrEntry(&p->vVar2Ids, k);
    assert( iSatVar > 0 && iSatVar < Vec_IntSize(vVar2Ids) );
    ObjId = Vec_IntEntry( vVar2Ids, iSatVar );
    if ( ObjId == -1 ) // activation variable
        return -1;
    pObj = Aig_ManObj( p->pAig, ObjId );
    if ( Saig_ObjIsLi( p->pAig, pObj ) )
        return Aig_ObjCioId(pObj)-Saig_ManPoNum(p->pAig);
    assert( 0 ); // should be called for register inputs only
    return -1;
}

/**Function*************************************************************

  Synopsis    [Returns register number for the given SAT variable.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
int Pdr_ObjRegNum( Pdr_Man_t * p, int k, int iSatVar )
{
    if ( p->pPars->fMonoCnf )
        return Pdr_ObjRegNum1( p, k, iSatVar );
    else
        return Pdr_ObjRegNum2( p, k, iSatVar );
}


/**Function*************************************************************

  Synopsis    [Returns the index of unused SAT variable.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
int Pdr_ManFreeVar( Pdr_Man_t * p, int k )
{
    if ( p->pPars->fMonoCnf )
        return sat_solver_nvars( Pdr_ManSolver(p, k) );
    else
    {
        Vec_Int_t * vVar2Ids = (Vec_Int_t *)Vec_PtrEntry( &p->vVar2Ids, k );
        Vec_IntPush( vVar2Ids, -1 );
        return Vec_IntSize( vVar2Ids ) - 1;
    }
}

/**Function*************************************************************

  Synopsis    [Creates SAT solver.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
static inline sat_solver * Pdr_ManNewSolver1( sat_solver * pSat, Pdr_Man_t * p, int k, int fInit )
{
    Aig_Obj_t * pObj;
    int i;
    assert( pSat );
    if ( p->pCnf1 == NULL )
    {
        int nRegs = p->pAig->nRegs;
        p->pAig->nRegs = Aig_ManCoNum(p->pAig);
        p->pCnf1 = Cnf_DeriveWithMan( p->pCnfMan, p->pAig, Aig_ManCoNum(p->pAig) );
        p->pAig->nRegs = nRegs;
        assert( p->vVar2Reg == NULL );
        p->vVar2Reg = Vec_IntStartFull( p->pCnf1->nVars );
        Saig_ManForEachLi( p->pAig, pObj, i )
            Vec_IntWriteEntry( p->vVar2Reg, Pdr_ObjSatVar(p, k, 3, pObj), i );
    }
    pSat = (sat_solver *)Cnf_DataWriteIntoSolverInt( pSat, p->pCnf1, 1, fInit );
    sat_solver_set_runtime_limit( pSat, p->timeToStop );
    return pSat;
}

/**Function*************************************************************

  Synopsis    [Creates SAT solver.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
static inline sat_solver * Pdr_ManNewSolver2( sat_solver * pSat, Pdr_Man_t * p, int k, int fInit )
{
    Vec_Int_t * vVar2Ids;
    int i, Entry;
    assert( pSat );
    if ( p->pCnf2 == NULL )
    {
        p->pCnf2     = Cnf_DeriveOtherWithMan( p->pCnfMan, p->pAig, 0 );
#ifdef USE_PG
        p->pCnf2->pClaPols = Cnf_DataDeriveLitPolarities( p->pCnf2 );
#endif
        p->pvId2Vars = ABC_CALLOC( Vec_Int_t, Aig_ManObjNumMax(p->pAig) );
        Vec_PtrGrow( &p->vVar2Ids, 256 );
    }
    // update the variable mapping
    vVar2Ids = (Vec_Int_t *)Vec_PtrGetEntry( &p->vVar2Ids, k );
    if ( vVar2Ids == NULL )
    {
        vVar2Ids = Vec_IntAlloc( 500 );
        Vec_PtrWriteEntry( &p->vVar2Ids, k, vVar2Ids );
    }
    Vec_IntForEachEntry( vVar2Ids, Entry, i )
    {
        if ( Entry == -1 )
            continue;
        assert( Vec_IntEntry( p->pvId2Vars + Entry, k ) > 0 );
        Vec_IntWriteEntry( p->pvId2Vars + Entry, k, 0 );
    }
    Vec_IntClear( vVar2Ids );
    Vec_IntPush( vVar2Ids, -1 );
    // start the SAT solver
//    pSat = sat_solver_new();
    sat_solver_setnvars( pSat, 500 );
    sat_solver_set_runtime_limit( pSat, p->timeToStop );
    return pSat;
}

/**Function*************************************************************

  Synopsis    [Creates SAT solver.]

  Description []
               
  SideEffects []

  SeeAlso     []

***********************************************************************/
sat_solver * Pdr_ManNewSolver( sat_solver * pSat, Pdr_Man_t * p, int k, int fInit )
{
    assert( pSat != NULL );
    if ( p->pPars->fMonoCnf )
        return Pdr_ManNewSolver1( pSat, p, k, fInit );
    else
        return Pdr_ManNewSolver2( pSat, p, k, fInit );
}


////////////////////////////////////////////////////////////////////////
///                       END OF FILE                                ///
////////////////////////////////////////////////////////////////////////


ABC_NAMESPACE_IMPL_END