/////////////////////////////////////////////////////////////// 
//  semi.cpp  -   build semiexpression, e.g., list of tokens //
//  ver 1.8       terminated by special characters           //
//                                                           //
//  Language:     Visual C++, ver 6.0                        //
//  Platform:     Micron Dual Pentium Pro 200, Win NT 4.0    //
//  Application:  CSE784 Example                             //
//  Author:       Jim Fawcett, CST 2-187, Syracuse Univ.     //
//                (315) 443-3948, fawcett@ecs.syr.edu        //
///////////////////////////////////////////////////////////////

#pragma warning(disable : 4786)
#include <cstdlib>
#include <algorithm>
#include "tok.h"
#include "semi.h"

using namespace std;

//----< constructor >------------------------------------------

semiExp::semiExp(istream &input) 
       : toker(input), _next(0), linesAtFirstTok(0) { }

//----< append token to end of semiExpression >----------------

int semiExp::append(const string &token) { 
  
  se.push_back(token);
  return se.size();
}

//----< return number of tokens in semiExpression >------------

int semiExp::length() const { return se.size(); }


//----< remove all elements from semiExpression >--------------

void semiExp::flush() { se.erase(se.begin(),se.end()); }

//----< is first char of token one of the special chars? >-----

bool semiExp::isTerminator(const string &token) {

  switch(token[0]) {
    case '{' : return true;
    case '}' : return true;
    case ';' : return true;
    case '\n': if(se.size() > 0)
                 if(se[0][0] == '#') return true;
               return false;
    default  : return false;
  }
}

//
//----< collect a semiExp from input stream >------------------

bool semiExp::get(bool includeNewline) {

  string tok;
  se.erase(se.begin(),se.end());
  _next = 0;
  bool more;
  while((more = toker.getTok(tok)) == true) {
    if(includeNewline || tok[0] != '\n') {
      if(se.size() == 0)
        linesAtFirstTok = lines();
      se.push_back(tok);
    }
    if(isTerminator(tok))
      break;
  }
  return more;
}

//----< how many lines when we collected first token? >--------

unsigned int semiExp::linesAtFirstToken() { return linesAtFirstTok; }

//----< if this condition is false, abort with message >-------

void semiExp::check(bool condition, const char *msg) {

  if(!condition) throw msg;
}

//----< index operator >---------------------------------------

string& semiExp::operator[](int n) { 

  check(0<=n && n<se.size(),"index error in operator[]");
  return se[n];
}

//----< additive assignment >----------------------------------

semiExp& semiExp::operator +=(const string &tok) {

  se.push_back(tok);
  return *this;
}

//----< send each token in semiExpression to stdout >----------

void semiExp::display(int i, int j) {

  int k;
  for(k=i; k<=j && k<se.size(); k++)
    cout << se[k] << " ";
  cout << "\n";
}
//

//----< is this token in semiExp? >----------------------------

int semiExp::find(const string &tok, int j) {

  int i;
  for(i=j; i<se.size(); i++)
    if(se[i] == tok) {
      _next = i+1;
      return i;
    }
  return se.size();
}

//----< is this string in token in semiExp? >------------------

int semiExp::textFind(const string &s, int j) {

  int i;
  for(i=j; i<se.size(); i++)
    if(se[i].find(s) < se[i].size()) {
      _next = i+1;
      return i;
    }
  return se.size();
}

//----< find next token match >--------------------------------

int semiExp::next(const string &tok) {

  int i;
  for(i=_next; i<se.size(); i++)
    if(se[i] == tok) {
      _next = i+1;
      return i;
    }
  return se.size();
}

//----< reset next count >-------------------------------------

void semiExp::resetNext() { _next = 0; }

//----< is this closing token match? >-------------------------

string semiExp::closes(const string &tok) {

  switch(tok[0]) {
    case '(' : return ")";
    case '[' : return "]";
    case '{' : return "}";
    default : return "no match";
  }
}

//

//----< find closure >-----------------------------------------
//
//  Useful only if preceded by successful search for '(' or '['

int semiExp::findClosure() {

  string tok;
  if(_next)
    tok = se[_next-1];
  else 
    return se.size();
  int i, level = 1;
  for(i=_next; i<se.size(); i++) {
    string temp = se[i];
    if(se[i] == tok)
      level++;
    else if(se[i] == closes(tok))
      level--;
    if(level == 0)
      return i;
  }
  return se.size();
}

//----< find extended closure >--------------------------------
//
//  Useful only if preceded by successful search for '(', '[', or '{'

int semiExp::findExClosure() {

  string tok;
  if(_next)
    tok = se[_next-1];
  else
    return -1;
  int i, level = 1;
  do {
    for(i=_next; i<se.size(); i++) {
      if(se[i] == tok)
        level++;
      else if(se[i] == closes(tok))
        level--;
      if(level == 0)
        return i;
    }
    _next = 0;
  } while(get());
  return -1;
}

//

//----< remove element at index i >----------------------------

void semiExp::remove(int i) {

  if(i<0 || se.size() <= i) return;
  if(i == _next-1) se.pop_back();
  vector<string>::iterator it = std::find(se.begin(),se.end(),se[i]);
  se.erase(it);
}

//----< constructor >------------------------------------------

packedTokens::packedTokens() {

  toks["::"] = both;
  toks["(" ] = both;
  toks[")" ] = both;
  toks["[" ] = both;
  toks["]" ] = both;
  toks["." ] = both;
  toks["," ] = left;
  toks[";" ] = left;
  toks["*" ] = right;
  toks["&" ] = right;
  toks[":" ] = not;
  toks["{" ] = not;
  toks["}" ] = not;
  toks["const"] = not;
}

//----< is this token in the packed token set >----------------

bool packedTokens::in(const string &s,packType pt) const {

  map<string,packType>::const_iterator it = toks.find(s);
  if(it != toks.end()) 
    if(it->second == pt)
      return true;
  return false;
}

//

//----< format semi-expression using token packing >-----------

string packedTokens::format(semiExp &se) {

  int i;
  string temp;
  for(i=0; i<se.length(); i++) {
    temp += se[i];

  // special cases
    if(i < se.length()-1) {
      if(se[i] == "}" && se[i+1] == ";")
        continue;

      if(se[i] == "(" && se[i+1] == "const")
        continue;
      
      if(se[i] == ")" && se[i+1] == "const") {
        temp += ' ';
        continue;
      }
      if(se[i] == "public" || se[i] == "protected" || se[i] == "private")
        if(se[i+1] == ":")
          continue;
    }

  // don't pack these
    if(in(se[i],packedTokens::not)) {
      temp += ' ';
      continue;
    }
    if(i<se.length()-1 && in(se[i+1],packedTokens::not)) {
      temp += ' ';
      continue;
    }

  // pack these on both sides
    if(i<se.length()-1 && in(se[i+1],packedTokens::both)) continue;
    if(in(se[i],packedTokens::both )) continue;
    
  // pack these on the right
        if(in(se[i],packedTokens::right)) continue;
    
  // pack these on left
    if(i<se.length()-1 && in(se[i+1],packedTokens::left)) continue;

  // otherwise don't pack
    temp += ' ';
  }
  return temp;
}
//

//----< test stub >--------------------------------------------

#ifdef TEST_SEMI

#include <fstream>
#include <strstream>

void main(int argc, char *argv[]) {

  ifstream in;
  semiExp se(in);

  if(argc == 1) {
    cout,"\n  please enter name of file to process\n";
    return;
  }

  cout << "\n  Testing Collection of SemiExpressions "
       << "\n =======================================\n";
  int i;
  for(i=1; i<argc; i++) {
    in.open(argv[i]);
    if(!in.good()) {
      cout << "\n  can't open file " << argv[i] << "\n\n";
      continue;
    }
    else
      cout << "\n  Collecting semiExps from file " << argv[i] << "\n\n";

    while(se.get()) {
      se.display();
      se.flush();
    }
    in.close();
    in.clear();
  }

//

  cout << "\n  Testing Closure operations "
       << "\n ============================\n";

  string s1 = "string& operator[](int n);";
  istrstream test1(s1.c_str());
  cout << "  analyzing string:  " << s1 << "\n\n";
  semiExp se1(test1);
  se1.get();
  int pos = se1.find("(");
  pos = se1.findClosure();
  cout << "  The closure of \"(\" is at position " << pos << '\n';

  string s2 = "if(pred) { cout x; } else cout y;";
  istrstream test2(s2.c_str());
  cout << "\n  analyzing string:  " << s2 << "\n\n";
  semiExp se2(test2);
  se2.get();
  se2.display();
  cout << "\n  finding closure of \"{\"\n\n";
  se2.find("{");
  se2.findExClosure();
  se2.display();
  se2.get();
  se2.display();

  cout << "\n  Testing index error handling "
       << "\n ==============================\n";

  try {
    se[-1];
  }
  catch(const char *msg) { cout << "  " << msg << "\n\n"; }

  cout << "\n  the number of lines in this file is: " 
       << se.lines() << '\n';
  cout << "\n  the net number of braces in this file is: " 
       << se.scopeLevel() << '\n';
  cout << "\n\n";
}

#endif