#include <string.h>
#include <unistd.h>
#include <pthread.h>
#if defined _WIN32 || defined _WIN64
/* for getpid */
#include <process.h>
/* Windows doesn't have snprintf */
#define snprintf _snprintf
#endif
#include <sqlcli1.h>
#include <postgres_ext.h>
#include "db2_fdw.h"

/** external variables */
extern DB2EnvEntry* rootenvEntry;          /* Linked list of handles for cached DB2 connections.            */

/** external prototypes */
extern void      db2Debug1            (const char* message, ...);
extern void      db2Debug2            (const char* message, ...);
extern void      db2Debug3            (const char* message, ...);
extern void      db2Error             (db2error sqlstate, const char* message);
extern void      db2Error_d           (db2error sqlstate, const char* message, const char* detail, ...);

/** inetrnal prototypes */
HdlEntry*        db2AllocStmtHdl      (SQLSMALLINT type, DB2ConnEntry* connp, db2error error, const char* errmsg);
void             printstruct          (void);

/** db2AllocStmtHdl
 *   Allocate an DB2 statement handle, keep it in the cached list.
 */
HdlEntry* db2AllocStmtHdl (SQLSMALLINT type, DB2ConnEntry* connp, db2error error, const char* errmsg) {
  HdlEntry* entry = NULL;
  SQLRETURN rc    = 0;

  db2Debug1("> db2AllocStmtHdl");
  printstruct();
  /* create entry for linked list */
  if ((entry = malloc (sizeof (HdlEntry))) == NULL) {
    db2Error_d (FDW_OUT_OF_MEMORY, "error allocating handle:"," failed to allocate %d bytes of memory", sizeof (HdlEntry));
  }
  db2Debug3("  entry allocated: %x",entry);
  rc = SQLAllocHandle(type, connp->hdbc, &(entry->hsql));
  if (rc != SQL_SUCCESS) {
    db2Debug3("  SQLAllocHandle not SQL_SUCCESS: %d",rc);
    free (entry);
    db2Debug3("  free entry: %x",entry);
    entry = NULL;
    db2Error (error, errmsg);
  } else {
    /* add handle to linked list */
    db2Debug2("  entry->hsql: %d",entry->hsql);
    entry->type         = type;
    db2Debug2("  entry->type: %d",entry->type);
    entry->next         = connp->handlelist;
    db2Debug3("  adding connp->handlelist: %x to entry->next: %x",connp->handlelist, entry->next);
    connp->handlelist   = entry;
    db2Debug3("  set entry %x to start connp->handlelist: %x",entry,connp->handlelist);
  }
  db2Debug1("< db2AllocStmtHdl - returns: %x",entry);
  return entry;
}

/** printstruct
 * 
 */
void  printstruct(void) {
  DB2EnvEntry*  envstep;
  DB2ConnEntry* constep;
  HdlEntry*     hdlstep;
  db2Debug2("  printstruct before calling pthread_create getpid: %d getpthread_self: %d", getpid(), (int)pthread_self());
  for (envstep = rootenvEntry; envstep != NULL; envstep = envstep->right){
    db2Debug2("  EnvEntry               : %x",envstep);
    db2Debug2("    nls_lang               : %s",envstep->nls_lang);
    db2Debug2("    step->henv             : %x",envstep->henv);
    db2Debug2("    step->*left            : %x",envstep->left);
    db2Debug2("    step->*right           : %x",envstep->right);
     db2Debug2("    step->*connlist        : %x",envstep->connlist);
    for (constep = envstep->connlist; constep != NULL; constep = constep->right){
      db2Debug2("      ConnEntr             : %x",constep);
      db2Debug2("        dbAlias              : %s",constep->srvname);
      db2Debug2("        user                 : %s",constep->uid);
      db2Debug2("        password             : %s",constep->pwd);
      db2Debug2("        xact_level           : %d",constep->xact_level);
      db2Debug2("        conattr              : %d",constep->conAttr);
      db2Debug2("        *handlelist          : %x",constep->handlelist);
      db2Debug2("        DB2ConnEntry *left   : %x",constep->left);
      db2Debug2("        Db2ConnEntry *right  : %x",constep->right);
      for (hdlstep = constep->handlelist; hdlstep != NULL; hdlstep = hdlstep->next){
        db2Debug2("          HandleEntry        : %x",hdlstep);
        db2Debug2("            hsql               : %d",hdlstep->hsql);
        db2Debug2("            type               : %d",hdlstep->type);
      }
    }
  }
}