#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "symbolMgt.h"

int                     TREE_NODE = 0,  TREE_STRUCT = 1; 
static char * typeNames[] = { "TREE_NODE",    "TREE_STRUCT"     };

typedef struct _Symbol
{
  char * name;    //  symbol name
  int    type;    //  symbol type
  void * ref;     //  ref of the object storing the symbol
} Symbol;

#define  INITIAL_SYMBOL_SIZE   50

Symbol *symbolTable = NULL;
int   symbolSize = 0;
int   symbolNb = 0;

/* Compares 2 symbol name (for qsort and bsearch) */
static int compar(const void *p1, const void *p2) {
  return strcmp(((Symbol *) p1)->name, ((Symbol *) p2)->name);
}


int insertInSymbolTable( char * symbolName, int type ){
  /* On verifie que le symbole n'est pas deja present. */
  Symbol symbolToFind;
  Symbol *pSymbol;
  symbolToFind.name = symbolName;
  pSymbol = bsearch(&symbolToFind, symbolTable, symbolNb, sizeof(Symbol), compar);
  if (pSymbol != NULL) {
    fprintf(stderr, "%s already at %d\n", symbolName, ((int)pSymbol - (int)symbolTable)/sizeof(Symbol));
    return EXIT_FAILURE;
  }

  /* On agrandit symbolTable si elle est trop petite pour accueillir */
  /* ce nouveau symbole.                                             */
  if (symbolNb >= symbolSize){
    if (symbolSize == 0) {
      symbolSize = INITIAL_SYMBOL_SIZE;
    }else{
      symbolSize *= 2;
    }
    symbolTable = realloc(symbolTable,symbolSize*sizeof(Symbol));
    if (symbolTable == NULL){
      error_at_line(EXIT_FAILURE, 0, "No more memory");
    }
  }

  /* On ajoute le symbole */
  symbolTable[symbolNb].name = strdup(symbolName);
  if (symbolTable[symbolNb].name == NULL) {
    error_at_line(EXIT_FAILURE, 0, "No more memory");
  }
  symbolTable[symbolNb].type = type;
  symbolTable[symbolNb].ref  = NULL;

  symbolNb++;

  fprintf(stderr, "%s inserted\n", symbolName);

  /* On trie la table avec ce nouvel element. */
  qsort(symbolTable, symbolNb, sizeof(Symbol), compar);

  return EXIT_SUCCESS;
}

int isInSymbolTable( char * symbolName) {
  Symbol symbolToFind;
  symbolToFind.name = symbolName;
  return (bsearch(&symbolToFind, symbolTable, symbolNb, sizeof(Symbol), compar) != NULL);
}

void printSymbolTable(){
  int i;
  for (i=0; i<symbolNb; i++){
    fprintf( stderr, "%s %s\n",
	     symbolTable[i].name,
	     typeNames[symbolTable[i].type]);
  }
}
  
void * getRefForSymbolInTable( char * symbolName ) {
  Symbol symbolToFind;
  Symbol *pSymbol;
  symbolToFind.name = symbolName;
  pSymbol = bsearch(&symbolToFind, symbolTable, symbolNb, sizeof(Symbol), compar);
  if (pSymbol == NULL){
    return NULL;
  }else{
    return pSymbol->ref;
  }
}

int setRefForSymbolInTable( char * symbolName , void * ref){
  Symbol symbolToFind;
  Symbol *pSymbol;
  symbolToFind.name = symbolName;
  pSymbol = bsearch(&symbolToFind, symbolTable, symbolNb, sizeof(Symbol), compar);
  if (pSymbol != NULL){
    pSymbol->ref = ref;
  }
  return 0; /* Specification is not clear what should be returned :-( */
}
  
char * firstTreeStructSymbolName( ){
  int i;
  for (i=0; i<symbolNb; i++){
    if (symbolTable[i].type == TREE_STRUCT) {
      return symbolTable[i].name;
    }
  }
  return NULL;
}

#ifdef TEST
#include <stdio.h>
#include <stdlib.h>
#include "symbolMgt.h"
int main( int argc, char *argv[] )
{
  int p;
  char *treeName;

  p = isInSymbolTable("AA");
  if (p == 0) 
	{
		fprintf(stderr, "AA not found\n");
	}
  else
    {
		fprintf(stderr, "AA found\n");
    }

  insertInSymbolTable( "YY", TREE_NODE );
  insertInSymbolTable( "VV", TREE_NODE );
  insertInSymbolTable( "WW", TREE_STRUCT );
  insertInSymbolTable( "XX", TREE_NODE );
  insertInSymbolTable( "ZZ", TREE_NODE );
  insertInSymbolTable( "VV", TREE_NODE );
  
  p = isInSymbolTable("XX");
  if (p == 0) 
	{
		fprintf(stderr, "XX not found\n");
	}
  else
    {
		fprintf(stderr, "XX found\n");
    }


  fprintf( stderr, "------------ symbolTable :\n");
  printSymbolTable( );
  fprintf( stderr, "\n" );

  treeName = firstTreeStructSymbolName( );
  fprintf( stderr, "treeName = %s\n",  treeName);
  return EXIT_SUCCESS;
}
#endif

#ifdef TEST2

int main( int argc, char *argv[] )
{
	int *ref1, *ref2;
  
  insertInSymbolTable( "AA", TREE_NODE );
  insertInSymbolTable( "BB", TREE_NODE );
  insertInSymbolTable( "WW", TREE_STRUCT );
  
  ref1 = malloc(sizeof(int));
  ref2 = malloc(sizeof(int));
  fprintf(stderr, "ref1 = %p\n", ref1);
  fprintf(stderr, "ref2 = %p\n", ref2);

  setRefForSymbolInTable("AA", ref1);
  setRefForSymbolInTable("BB", ref2);
  setRefForSymbolInTable("CC", ref2); /* incorrect but should not crash */

  fprintf( stderr, "------------ symbolTable :\n");
  printSymbolTable( );
  fprintf( stderr, "\n" );

  fprintf(stderr, "AA ref1 = %p\n", getRefForSymbolInTable("AA"));
  fprintf(stderr, "BB ref2 = %p\n", getRefForSymbolInTable("BB"));
  fprintf(stderr, "WW ref3 = %p\n", getRefForSymbolInTable("WW")); /* incorrect but should not crash */
  return EXIT_SUCCESS;
}
#endif