#include "ClangASTNodesEmitter.h"
#include "Record.h"
#include <vector>
#include <stack>
#include <string>
#include <map>
#include <utility>
#include <cctype>
using namespace llvm;

//===----------------------------------------------------------------------===//
// Statement Node Tables (.inc file) generation.
//===----------------------------------------------------------------------===//

// Sort to create a tree-like structure based on the 'Base' field.
namespace {
  // Create a macro-ized version of a name
  std::string macroName(std::string S) {
    for (unsigned i = 0; i < S.size(); ++i)
      S[i] = std::toupper(S[i]);

    return S;
  }

  // A map from a node to each of its derived nodes.
  typedef std::multimap<Record*, Record*> ChildMap;
  typedef ChildMap::const_iterator ChildIterator;

  // Returns the first and last non-abstract subrecords
  std::pair<Record *, Record *> EmitStmtNode(const ChildMap &Tree,
                                             raw_ostream &OS, Record *Base) {
    std::string BaseName = macroName(Base->getName());

    ChildIterator i = Tree.lower_bound(Base), e = Tree.upper_bound(Base);

    Record *First = 0, *Last = 0;
    // This might be the pseudo-node for Stmt; don't assume it has an Abstract
    // bit
    if (Base->getValue("Abstract") && !Base->getValueAsBit("Abstract"))
      First = Last = Base;

    for (; i != e; ++i) {
      Record *R = i->second;
      bool Abstract = R->getValueAsBit("Abstract");
      std::string NodeName = macroName(R->getName());

      OS << "#ifndef " << NodeName << "\n";
      OS << "#  define " << NodeName << "(Type, Base) "
         << BaseName << "(Type, Base)\n";
      OS << "#endif\n";

      if (Abstract)
        OS << "ABSTRACT(" << NodeName << "(" << R->getName() << ", "
           << Base->getName() << "))\n";
      else
        OS << NodeName << "(" << R->getName() << ", "
           << Base->getName() << ")\n";

      if (Tree.find(R) != Tree.end()) {
        const std::pair<Record *, Record *> &Result = EmitStmtNode(Tree, OS, R);
        if (!First && Result.first)
          First = Result.first;
        if (Result.second)
          Last = Result.second;
      } else {
        if (!Abstract) {
          Last = R;

          if (!First)
            First = R;
        }
      }

      OS << "#undef " << NodeName << "\n\n";
    }

    assert(!First == !Last && "Got a first or last node, but not the other");

    if (First) {
      OS << "#ifndef FIRST_" << BaseName << "\n";
      OS << "#  define FIRST_" << BaseName << "(CLASS)\n";
      OS << "#endif\n";
      OS << "#ifndef LAST_" << BaseName << "\n";
      OS << "#  define LAST_" << BaseName << "(CLASS)\n";
      OS << "#endif\n\n";

      OS << "FIRST_" << BaseName << "(" << First->getName() << ")\n";
      OS << "LAST_" << BaseName << "(" << Last->getName() << ")\n\n";
    }

    OS << "#undef FIRST_" << BaseName << "\n";
    OS << "#undef LAST_" << BaseName << "\n\n";

    return std::make_pair(First, Last);
  }
}

void ClangStmtNodesEmitter::run(raw_ostream &OS) {
  // Write the preamble
  OS << "#ifndef ABSTRACT\n";
  OS << "#  define ABSTRACT(Stmt) Stmt\n";
  OS << "#endif\n\n";

  // Emit statements
  const std::vector<Record*> Stmts = Records.getAllDerivedDefinitions("Stmt");

  ChildMap Tree;

  // Create a pseudo-record to serve as the Stmt node, which isn't actually
  // output.
  Record Stmt ("Stmt", SMLoc());

  for (unsigned i = 0, e = Stmts.size(); i != e; ++i) {
    Record *R = Stmts[i];

    if (R->getValue("Base"))
      Tree.insert(std::make_pair(R->getValueAsDef("Base"), R));
    else
      Tree.insert(std::make_pair(&Stmt, R));
  }

  EmitStmtNode(Tree, OS, &Stmt);

  OS << "#undef STMT\n";
  OS << "#undef ABSTRACT\n";
}