//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
//+      Student:          Junshan Li                              +
//+      Proj. Assignemnt: Five                                    +
//+      Due Date:         Febuary 26, 2001                        +
//+      Course Name:      MSCS 518 - Compiler Design              +       
//++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

// rwtable.cpp
// rwtable class implementation.

#include <iostream.h>
#include <string.h>
#include "rwtable.h"

rwtable::rwtable() {
   for (int ch = ' '; ch <= '~'; ch++) C[ch] = 100;

   C['A'] = 1; C['B'] = -8; C['C'] = 6; C['D'] = 0; C['E'] = -1;
   C['F'] = 0; C['I'] = 21; C['M'] = -7; C['N'] = 3; C['O'] = 0;
   C['P'] = 3; C['R'] = -3; C['S'] = 25; C['T'] = -2; C['V'] = 22;
   C['W'] = 11; C['Y'] = 5;

   //========= 0       1        2           3         4      5
   char *rwArr1[35] = {"BY", 
                    "READ",  "BOOLEAN", "PROGRAM", "REF",  "DO", 
                    "ODD",   "CHAR",    "BEGIN",    "THEN", "MOD", 
                    "ARRAY", "RESULT",  "OR",       "FOR",  "END", 
                    "OF",    "AND",     "NOT",      "TO",   "ELSE", 
                    "TRUE", "FALSE", "DECLARE", "FORWARD", "FUNCTION", 
                    "WHILE", "CONST", "PROCEDURE", "INTEGER", "ABS", 
                    "IF", "WRITELN", "DIV", "WRITE" };

   for (int i = 0; i < 35; i++) {
      rwArr[i] = rwArr1[i];
      //cout << i << ":" << rwArr[i] << ";";
   }
   cout << endl;

   /***
   for (ch = 'A'; ch <= 'Z'; ch++) {
      cout << "C['" << char(ch) << "'] = " << C[ch] << "; ";
   }
   cout << endl;
   ***/
}              

void rwtable::display() {  // Display reserved word table characteristics.
   cout << "===== Displaying Reserved Word index ======\n";
   cout << "Reserved Word\t" << "Index" << endl;
   for (int i = 0; i < 35; i++) {
      cout << rwArr[i] << "\t" << i << endl;
   }

   cout << "\n===== Displaying Charactor code ======\n";
   for (int ch = 'A'; ch <= 'Z'; ch++) {
      cout << "Char. code for: " << char(ch) << ": " 
           << C[ch] << endl;
   }

   cout << "\n===== Displaying hashCode for each reserved word =====\n";
   for (i = 0; i < 35; i++) {
      int hashCode;
      hashCode = rwhash(rwArr[i]);
      cout << "The rw was: " << rwArr[i] << " the hash code was: "
           << hashCode << endl;
   }
}

int rwtable::numPosCode(int c) {
   int positionCode;
   int codeArr[26] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
                  16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26};
   return codeArr[c-int('A')];
}

int rwtable::rwhash(char* w) {
   const first = 0;
   //cout << "In rwtable::rwhash, w == " << w << endl;
   int last = strlen(w) - 1;
   int code = 1;   // initialize the code of 'A' to 0.
   int hashCode;

   hashCode = C[w[first]] + C[w[last]] + last 
              + numPosCode(w[last-1]); // using last instead of last+1

   return hashCode;
}