/******************************************************************************
 * Top contributors (to current version):
 *   Andrew Reynolds, Tim King, Haniel Barbosa
 *
 * This file is part of the cvc5 project.
 *
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
 * in the top-level source directory and their institutional affiliations.
 * All rights reserved.  See the file COPYING in the top-level source
 * directory for licensing information.
 * ****************************************************************************
 *
 * Theory of separation logic.
 */

#include "cvc5_private.h"

#ifndef CVC5__THEORY__SEP__THEORY_SEP_H
#define CVC5__THEORY__SEP__THEORY_SEP_H

#include "context/cdhashmap.h"
#include "context/cdhashset.h"
#include "context/cdlist.h"
#include "context/cdqueue.h"
#include "theory/decision_strategy.h"
#include "theory/inference_manager_buffered.h"
#include "theory/sep/theory_sep_rewriter.h"
#include "theory/theory.h"
#include "theory/theory_state.h"
#include "theory/uf/equality_engine.h"
#include "util/statistics_stats.h"

namespace cvc5 {
namespace theory {

class TheoryModel;

namespace sep {

class TheorySep : public Theory {
  typedef context::CDList<Node> NodeList;
  typedef context::CDHashSet<Node> NodeSet;
  typedef context::CDHashMap<Node, Node> NodeNodeMap;

  /////////////////////////////////////////////////////////////////////////////
  // MISC
  /////////////////////////////////////////////////////////////////////////////

 private:
  /** all lemmas sent */
  NodeSet d_lemmas_produced_c;

  /** True node for predicates = true */
  Node d_true;

  /** True node for predicates = false */
  Node d_false;

  //whether bounds have been initialized
  bool d_bounds_init;

  TheorySepRewriter d_rewriter;
  /** A (default) theory state object */
  TheoryState d_state;
  /** A buffered inference manager */
  InferenceManagerBuffered d_im;

  Node mkAnd( std::vector< TNode >& assumptions );

  int processAssertion(
      Node n,
      std::map<int, std::map<Node, int> >& visited,
      std::map<int, std::map<Node, std::vector<Node> > >& references,
      std::map<int, std::map<Node, bool> >& references_strict,
      bool pol,
      bool hasPol,
      bool underSpatial);

 public:
  TheorySep(context::Context* c,
            context::UserContext* u,
            OutputChannel& out,
            Valuation valuation,
            const LogicInfo& logicInfo,
            ProofNodeManager* pnm = nullptr);
  ~TheorySep();

  /**
   * Declare heap. For smt2 inputs, this is called when the command
   * (declare-heap (locT datat)) is invoked by the user. This sets locT as the
   * location type and dataT is the data type for the heap. This command can be
   * executed once only, and must be invoked before solving separation logic
   * inputs.
   */
  void declareSepHeap(TypeNode locT, TypeNode dataT) override;

  //--------------------------------- initialization
  /** get the official theory rewriter of this theory */
  TheoryRewriter* getTheoryRewriter() override;
  /** get the proof checker of this theory */
  ProofRuleChecker* getProofChecker() override;
  /**
   * Returns true if we need an equality engine. If so, we initialize the
   * information regarding how it should be setup. For details, see the
   * documentation in Theory::needsEqualityEngine.
   */
  bool needsEqualityEngine(EeSetupInfo& esi) override;
  /** finish initialization */
  void finishInit() override;
  //--------------------------------- end initialization
  /** preregister term */
  void preRegisterTerm(TNode n) override;

  std::string identify() const override { return std::string("TheorySep"); }

  /////////////////////////////////////////////////////////////////////////////
  // PREPROCESSING
  /////////////////////////////////////////////////////////////////////////////

 public:
  void ppNotifyAssertions(const std::vector<Node>& assertions) override;
  /////////////////////////////////////////////////////////////////////////////
  // T-PROPAGATION / REGISTRATION
  /////////////////////////////////////////////////////////////////////////////

 private:
  /** Should be called to propagate the literal.  */
  bool propagateLit(TNode literal);
  /** Conflict when merging constants */
  void conflict(TNode a, TNode b);

 public:
  TrustNode explain(TNode n) override;

 public:
  void computeCareGraph() override;

  /////////////////////////////////////////////////////////////////////////////
  // MODEL GENERATION
  /////////////////////////////////////////////////////////////////////////////

 public:
  void postProcessModel(TheoryModel* m) override;

  /////////////////////////////////////////////////////////////////////////////
  // NOTIFICATIONS
  /////////////////////////////////////////////////////////////////////////////

 public:

  void presolve() override;
  void shutdown() override {}

  /////////////////////////////////////////////////////////////////////////////
  // MAIN SOLVER
  /////////////////////////////////////////////////////////////////////////////

  //--------------------------------- standard check
  /** Do we need a check call at last call effort? */
  bool needsCheckLastEffort() override;
  /** Post-check, called after the fact queue of the theory is processed. */
  void postCheck(Effort level) override;
  /** Pre-notify fact, return true if processed. */
  bool preNotifyFact(TNode atom,
                     bool pol,
                     TNode fact,
                     bool isPrereg,
                     bool isInternal) override;
  /** Notify fact */
  void notifyFact(TNode atom, bool pol, TNode fact, bool isInternal) override;
  //--------------------------------- end standard check

 private:
  /** Ensures that the reduction has been added for the given fact */
  void reduceFact(TNode atom, bool polarity, TNode fact);
  /** Is spatial kind? */
  bool isSpatialKind(Kind k) const;
  // NotifyClass: template helper class for d_equalityEngine - handles
  // call-back from congruence closure module
  class NotifyClass : public eq::EqualityEngineNotify
  {
    TheorySep& d_sep;

   public:
    NotifyClass(TheorySep& sep) : d_sep(sep) {}

    bool eqNotifyTriggerPredicate(TNode predicate, bool value) override
    {
      Debug("sep::propagate")
          << "NotifyClass::eqNotifyTriggerPredicate(" << predicate << ", "
          << (value ? "true" : "false") << ")" << std::endl;
      Assert(predicate.getKind() == kind::EQUAL);
      // Just forward to sep
      if (value)
      {
        return d_sep.propagateLit(predicate);
      }
      return d_sep.propagateLit(predicate.notNode());
    }
    bool eqNotifyTriggerTermEquality(TheoryId tag,
                                     TNode t1,
                                     TNode t2,
                                     bool value) override
    {
      Debug("sep::propagate")
          << "NotifyClass::eqNotifyTriggerTermEquality(" << t1 << ", " << t2
          << ", " << (value ? "true" : "false") << ")" << std::endl;
      if (value)
      {
        // Propagate equality between shared terms
        return d_sep.propagateLit(t1.eqNode(t2));
      }
      return d_sep.propagateLit(t1.eqNode(t2).notNode());
    }

    void eqNotifyConstantTermMerge(TNode t1, TNode t2) override
    {
      Debug("sep::propagate") << "NotifyClass::eqNotifyConstantTermMerge(" << t1
                              << ", " << t2 << ")" << std::endl;
      d_sep.conflict(t1, t2);
    }

    void eqNotifyNewClass(TNode t) override {}
    void eqNotifyMerge(TNode t1, TNode t2) override
    {
      d_sep.eqNotifyMerge(t1, t2);
    }
    void eqNotifyDisequal(TNode t1, TNode t2, TNode reason) override {}
  };

  /** The notify class for d_equalityEngine */
  NotifyClass d_notify;

  /** list of all refinement lemms */
  std::map< Node, std::map< Node, std::vector< Node > > > d_refinement_lem;

  //cache for positive polarity start reduction
  NodeSet d_reduce;
  std::map< Node, std::map< Node, Node > > d_red_conc;
  std::map< Node, std::map< Node, Node > > d_neg_guard;
  std::vector< Node > d_neg_guards;
  /** a (singleton) decision strategy for each negative guard. */
  std::map<Node, std::unique_ptr<DecisionStrategySingleton> >
      d_neg_guard_strategy;
  std::map< Node, Node > d_guard_to_assertion;
  NodeList d_spatial_assertions;

  //data,ref type (globally fixed)
  TypeNode d_type_ref;
  TypeNode d_type_data;
  //currently fix one data type for each location type, throw error if using more than one
  std::map< TypeNode, TypeNode > d_loc_to_data_type;
  //information about types
  std::map< TypeNode, Node > d_base_label;
  std::map< TypeNode, Node > d_nil_ref;
  //reference bound
  std::map< TypeNode, Node > d_reference_bound;
  std::map< TypeNode, Node > d_reference_bound_max;
  std::map< TypeNode, std::vector< Node > > d_type_references;
  //kind of bound for reference types
  enum {
    bound_strict,
    bound_default,
    bound_invalid,
  };
  std::map< TypeNode, unsigned > d_bound_kind;

  std::map< TypeNode, std::vector< Node > > d_type_references_card;
  std::map< Node, unsigned > d_type_ref_card_id;
  std::map< TypeNode, std::vector< Node > > d_type_references_all;
  std::map< TypeNode, unsigned > d_card_max;
  //for empty argument
  std::map< TypeNode, Node > d_emp_arg;
  //map from ( atom, label, child index ) -> label
  std::map< Node, std::map< Node, std::map< int, Node > > > d_label_map;
  std::map< Node, Node > d_label_map_parent;

  //term model
  std::map< Node, Node > d_tmodel;
  std::map< Node, Node > d_pto_model;

  class HeapAssertInfo {
  public:
    HeapAssertInfo( context::Context* c );
    ~HeapAssertInfo(){}
    context::CDO< Node > d_pto;
    context::CDO< bool > d_has_neg_pto;
  };
  std::map< Node, HeapAssertInfo * > d_eqc_info;
  HeapAssertInfo * getOrMakeEqcInfo( Node n, bool doMake = false );

  //get global reference/data type
  TypeNode getReferenceType( Node n );
  TypeNode getDataType( Node n );
  /**
   * Register reference data types for atom. Calls the method below for
   * the appropriate types.
   */
  void registerRefDataTypesAtom(Node atom);
  /**
   * This is called either when:
   * (A) a declare-heap command is issued with tn1/tn2, and atom is null, or
   * (B) an atom specifying the heap type tn1/tn2 is registered to this theory.
   * We set the heap type if we are are case (A), and check whether the
   * heap type is consistent in the case of (B).
   */
  void registerRefDataTypes(TypeNode tn1, TypeNode tn2, Node atom);
  //get location/data type
  //get the base label for the spatial assertion
  Node getBaseLabel( TypeNode tn );
  Node getNilRef( TypeNode tn );
  void setNilRef( TypeNode tn, Node n );
  Node getLabel( Node atom, int child, Node lbl );
  Node applyLabel( Node n, Node lbl, std::map< Node, Node >& visited );
  void getLabelChildren( Node atom, Node lbl, std::vector< Node >& children, std::vector< Node >& labels );

  class HeapInfo {
  public:
    HeapInfo() : d_computed(false) {}
    //information about the model
    bool d_computed;
    std::vector< Node > d_heap_locs;
    std::vector< Node > d_heap_locs_model;
    //get value
    Node getValue( TypeNode tn );
  };
  //heap info ( label -> HeapInfo )
  std::map< Node, HeapInfo > d_label_model;
  // loc -> { data_1, ..., data_n } where (not (pto loc data_1))...(not (pto loc data_n))).
  std::map< Node, std::vector< Node > > d_heap_locs_nptos;

  void debugPrintHeap( HeapInfo& heap, const char * c );
  void validatePto( HeapAssertInfo * ei, Node ei_n );
  void addPto( HeapAssertInfo * ei, Node ei_n, Node p, bool polarity );
  void mergePto( Node p1, Node p2 );
  void computeLabelModel( Node lbl );
  Node instantiateLabel(Node n,
                        Node o_lbl,
                        Node lbl,
                        Node lbl_v,
                        std::map<Node, Node>& visited,
                        std::map<Node, Node>& pto_model,
                        TypeNode rtn,
                        std::map<Node, bool>& active_lbl,
                        unsigned ind = 0);
  void setInactiveAssertionRec( Node fact, std::map< Node, std::vector< Node > >& lbl_to_assertions, std::map< Node, bool >& assert_active );

  Node mkUnion( TypeNode tn, std::vector< Node >& locs );

 private:
  Node getRepresentative( Node t );
  bool hasTerm( Node a );
  bool areEqual( Node a, Node b );
  bool areDisequal( Node a, Node b );
  void eqNotifyMerge(TNode t1, TNode t2);

  void sendLemma( std::vector< Node >& ant, Node conc, InferenceId id, bool infer = false );
  void doPending();

 public:

  void initializeBounds();
};/* class TheorySep */

}  // namespace sep
}  // namespace theory
}  // namespace cvc5

#endif /* CVC5__THEORY__SEP__THEORY_SEP_H */