#include "easycsv.h"

/* Flags  */
typedef enum {
  EASYCSV_NONE,
  EASYCSV_STRING,
  EASYCSV_INT,
  EASYCSV_UNKNOWN
} _EASYCSV_TYPE;

typedef enum {
  
  /* Generic errors */
  EASYCSV_NOERROR = 0, // no error
  EASYCSV_NULLCSV, // easycsv* is NULL
  EASYCSV_NULLPTR, // generic pointer is NULL
  EASYCSV_EMPTYSTRING, // empty string
  EASYCSV_OVERMAXROW, // int exceeds row limit
  EASYCSV_OVERMAXCOL, // int exceeds col limit
  EASYCSV_ZEROROW,
  EASYCSV_ZEROCOL,
  
  /* File input/output errors */
  EASYCSV_UNKNOWNMODE, // unknown file IO mode
  EASYCSV_OPENFAIL, // fail to open
  EASYCSV_REOPENFAIL, // fail to reopen
  EASYCSV_EMPTYCSV, // csv is empty or does not exist
  EASYCSV_UNWRITABLE, // csv mode not at EASYCSV_W
  EASYCSV_UNREADABLE, // csv mode not at EASYCSV_R
  EASYCSV_UPDATEFAIL, // update file fail
  EASYCSV_FILEPTRFAIL, // move file pointer fail

  /* Non-existant elements */
  EASYCSV_ROWNOTEXIST, // row does not exist
  EASYCSV_COLNOTEXIST, // column does not exist

  /* Subroutine failure */
  EASYCSV_PUSHCOLFAIL, // push column value fail
  EASYCSV_COLNUMFAIL // column number retrieval fail
} EASYCSV_ERROR;

typedef struct _easycsv {
  FILE *file; // original CSV file
  FILE *temp; // temporary CSV file for writing
  char *fp;
  char *tmpfp;
  unsigned int rows;
  unsigned int cols;
  EASYCSV_ERRORMSG error;
#ifdef EASYCSV_DEBUG
  clock_t start;
#endif
} _easycsv;

/* PRIVATE FUNCTIONS */

/* Constructor of private members */
static _easycsv *_easycsv_priv_init(const char*, const EASYCSV_MODE, const EASYCSV_ERRORMSG);

/* Destructor of private members */
static void _easycsv_priv_free(_easycsv*);

/* Verifies mode of file */
// static int _easycsv_checkmode(struct easycsv*, const char);

/* Copies data from temp FILE to file FILE */
static int _easycsv_update(easycsv*);

/* Rewind easycsv, checks for readability */
static int _easycsv_rewind(_easycsv*, const EASYCSV_MODE);

/* Returns string of a specific row */
static char *_easycsv_getrow(const easycsv*, const unsigned int);

/* Return column number of a named column */
static int _easycsv_getcolumn(const easycsv*, const char*);

/* Verifies the type of the value (eg:  string or int) */
static int _easycsv_checktype(const easycsv*, const int, const int);

/* Verifies if there is a value or not */
static int _easycsv_checkifvalue(const easycsv*, const int, const int);

/*  */ 
// static char *_easycsv_getvalueinrow(const int, const char*);

/* Calculate rows */
static int _easycsv_rows(_easycsv*, const EASYCSV_MODE);

/* Calculate columns*/
static int _easycsv_columns(_easycsv*, const EASYCSV_MODE);

static void _easycsv_printerror(const _easycsv*, const EASYCSV_ERROR);

/* Print error from _easycsv struct in stderr */
static void _easycsv_geterror(const _easycsv*, const EASYCSV_ERROR, FILE*);

/* Check if easycsv* and const char* are NULL */
static int _easycsv_checkcsvandstring_one(const easycsv*, const char*);

/* Check if easycsv* and two const char* are NULL*/
static int _easycsv_checkcsvandstring_two(const easycsv*, const char*, const char*);

/* Verifies if the string is not NULL or empty, returns 0 on success and -1 on failure */
// static int _easycsv_checkstring(const char*);

/* Verifies if easycsv is not NULL or unallocated */
// static int _easycsv_checkeasycsv(const struct easycsv*);

/* Verifies if int is  */
// static int _easycsv_checkunsigned(const int);

/* 
 * ====================
 * FUNCTION DEFINITIONS
 * ====================
 */

/* PUBLIC FUNCTIONS */

easycsv*
easycsv_init(const char *fp, const EASYCSV_MODE mode)
{
  return easycsv_init_errormsg(fp, mode, EASYCSV_ERRORSTDERR);
}

easycsv*
easycsv_init_errormsg(const char *fp, const EASYCSV_MODE mode, const EASYCSV_ERRORMSG error)
{
#ifdef EASYCSV_DEBUG
  csv->start = clock();
#endif
  
  easycsv *csv = malloc(sizeof *csv);
  csv->mode = mode;
  csv->_priv = _easycsv_priv_init(fp, mode, error);
  
  if (csv->_priv == NULL) {
    easycsv_free(csv);
    return NULL;
  }
  
  return csv;
}

void
easycsv_free(easycsv *csv)
{
  if (csv == NULL) return;
  _easycsv_priv_free(csv->_priv);
  free(csv);
}

_easycsv*
_easycsv_priv_init(const char *fp, const EASYCSV_MODE mode, const EASYCSV_ERRORMSG error)
{
  _easycsv *_priv = malloc(sizeof *_priv);
  memset(_priv, 0, sizeof(*_priv)); // set all members to NULL

  _priv->error = error;
  
  /* Open file according to mode */
  switch (mode) {
  case EASYCSV_R:
  case EASYCSV_W: {
    _priv->file = fopen(fp, "r");
    break;
  }
  default: {
    _easycsv_printerror(_priv, EASYCSV_UNKNOWNMODE);
    _easycsv_priv_free(_priv);
    return NULL;
  }
  
  if (_priv->file == NULL)
  {
    _easycsv_printerror(_priv, EASYCSV_OPENFAIL);
    _easycsv_priv_free(_priv);
    return NULL;
  }

  size_t stfp = strlen(fp);
  
  /* Allocate memory for char* */
  _priv->fp = malloc(stfp + 1); // + 1 for null
  
  strncpy(_priv->fp, fp, stfp);

  /* Calculate rows and cols if file exists */
  if (access(_priv->fp, F_OK) == 0) {
    _priv->rows = _easycsv_rows(_priv, mode);
    _priv->cols = _easycsv_columns(_priv, mode);
  }
  else {
    _priv->rows = 0;
    _priv->cols = 0;
  }

   if (mode == EASYCSV_W) {
    
    /* csv->tmpfp = malloc(16 + stfp + 1); */
    /* strncpy(csv->tmpfp, prefix, 16); */
    /* strncat(csv->tmpfp, fp, stfp); */
    
    do {
      /* Write to temporary file */
      unsigned int i = 1;
      char buffer[21] = "/tmp/easycsv-"; // 13 char,  3 for digits, 4 for .csv, 1 for NULL
      char *pbuffer = &buffer[13]; // don't free, is used for digit con
    
      if (i < 100) {
	strncpy(pbuffer, "0", 1);
	pbuffer++;
      }
	
      if (i < 10) {
	strncpy(pbuffer, "0", 1);
	pbuffer++;
      }
	
      sprintf(pbuffer, "%i", i);
      strncpy(++pbuffer, ".csv", 4);
      buffer[20] = '\0';

      if (access(buffer, F_OK) < 0) {
	i++;
      }
      else {
	_priv->tmpfp = malloc(21);
	strncpy(_priv->tmpfp, buffer, 21);
	break;
      }
      
    } while (1);

    _priv->temp = fopen(_priv->tmpfp, "w");
    if (_priv->temp == NULL) {
      _easycsv_printerror(_priv, EASYCSV_OPENFAIL);
      _easycsv_priv_free(_priv);
      return NULL;
    }
    /*
#ifdef EASYCSV_DEBUG
    printf("[%i] easycsv_debug: temp file %s opened\n", clock() - csv->start, csv->tmpfp);
    #endif*/
    /*
   
    if (freopen(csv->fp, csv->mode, csv->file) == NULL) {
      fprintf(stderr, "easycsv: failed to set temporary file %s to %s mode\n", csv->tmpfp, csv->mode);
      return NULL;
    }

    if (freopen(csv->tmpfp, csv->mode, csv->temp) == NULL) {
      fprintf(stderr, "easycsv: failed to set temporary file %s to %s mode\n", csv->tmpfp, csv->mode);
      return NULL;
    }
    */
    
  }
  
  return _priv;
}
 
void
_easycsv_priv_free(_easycsv *_priv)
{
  if (_priv == NULL) return;
  if (_priv->file != NULL) fclose(_priv->file);
  if (_priv->temp != NULL) fclose(_priv->temp);
  if (_priv->fp != NULL) free(_priv->fp);
  if (_priv->tmpfp != NULL) free(_priv->tmpfp);
  free(_priv);
}

  
int
easycsv_pushcolumn(easycsv *csv, const char *col)
{
  if (_easycsv_checkcsvandstring_one(csv, col) < 0) return -1;
  
  if (csv->mode == EASYCSV_R) {
     _easycsv_printerror(csv->_priv, EASYCSV_UNWRITABLE);
    return -1;
  }
      
  if ((csv->mode == EASYCSV_W) && (access(csv->_priv->fp, F_OK) == 0)) {
    /* If the file doesn't exist, just put the col in the file */

    if (fputs(col, csv->_priv->file) < 0) {
      _easycsv_printerror(csv->_priv, EASYCSV_PUSHCOLFAIL);
      return -1;
    }

    return 0;
  }

  char *str = _easycsv_getrow(csv, 1);
  size_t ststr = strlen(str);
  size_t stcol = strlen(col);
  realloc(str, ststr + stcol + 2); // 1 for null and 1 for comma

  strncat(str + ststr, ",", 1);
  strncat(str + ststr + 1, col, stcol);
  /*
#ifdef EASYCSV_DEBUG
  printf("[%i] easycsv_debug: push column str: %s", clock() - csv->_priv->start, str);
#endif
  */
  /* Put str in temp file */
  if (fputs(str, csv->_priv->temp) < 0) {
     _easycsv_printerror(csv->_priv, EASYCSV_PUSHCOLFAIL);
    return -1;
  }

  free(str);

  /* Copy every row following the first into temp */
  for (int i = 2; i <= csv->_priv->rows; i++) {
    char *row = _easycsv_getrow(csv, i);
    fputs(row, csv->_priv->temp);
    free(row);
  }

  /* Update the file */
  if (_easycsv_update(csv) < 0) {
     _easycsv_printerror(csv->_priv, EASYCSV_UPDATEFAIL);
    return -1;
  }
  
  return 0;
}

int
easycsv_pushcolumnvalue(const easycsv *csv, const char *col, const char *val)
{
  if (_easycsv_checkcsvandstring_two(csv, col, val) < 0) return -1;
  
  int colnum = _easycsv_getcolumn(csv, col);

  if (colnum < 0) {
    _easycsv_printerror(csv->_priv, EASYCSV_COLNUMFAIL);
    return -1;
  }

  /* Find a free cell under col within csv->_priv->cols limits, if there is none, generate a new
     row */
  unsigned int row;

  for (row = 2; row <= csv->_priv->cols; row++) {
    if (easycsv_readvalue(csv, colnum, row) != NULL) break;
  }

  /* All rows are filled, generate new row */
  if (row == csv->_priv->cols) {
    row++;
    
    /* Set file pointer to end */
    if (fseek(csv->_priv->file, 0L, SEEK_END) < 0) {
      _easycsv_printerror(csv->_priv, EASYCSV_FILEPTRFAIL);
      return -1;
    }

    char *rowstr = malloc(csv->_priv->cols + strlen(val) + 2); // 1 extra for '\n'

    strncpy(rowstr, "\n", 1);
    
    for (unsigned int i = 1; i < colnum; i++) {
      strncpy(rowstr, ",", 1);
    }

    strncpy(rowstr, val, strlen(val));

    unsigned int colsleft = csv->_priv->cols - colnum;
    
    for (unsigned i = 1; i < colsleft; i++) {
      strncpy(rowstr, ",", 1);
    }

    strncpy(rowstr, "/0", 1);

    csv->_priv->rows++;
  }

  /* Fill in rows before  */
  
  for (unsigned int i = 1; i < row; i++) {
    char *str = _easycsv_getrow(csv, i);
    if (fputs(str, csv->_priv->temp) == EOF) {
      fprintf(stderr, "easycsv: failed to write \"%s\" in temporary file %s for %s\n", str, csv->_priv->tmpfp, csv->_priv->fp);
      return -1;
    }
    
    free(str);
  }
  
  return 0;
}

int
easycsv_insertcolumnvalue(const easycsv *csv, const char *col, const unsigned int row, const char *val, const EASYCSV_VALMODE valmode)
{
  if (_easycsv_checkcsvandstring_two(csv, col, val) < 0) return -1;

  int colnum = _easycsv_getcolumn(csv, col);
  if (colnum < 0) {
    _easycsv_printerror(csv->_priv, EASYCSV_COLNUMFAIL);
    return -1;
  }
  
  char *rowstr = _easycsv_getrow(csv, row);
  char *pch = rowstr;
  
  for (unsigned int i = 1; i < colnum; i++) {
    pch = strchr(pch, ',');
    pch++;
  }

  size_t st = strcspn(pch, ',');

  /* Empty cell */
  if (st == 0) {
    
  }
  
  return 0;
}

int
easycsv_printrows(const easycsv *csv)
{
  return csv->_priv->rows;
}

int
easycsv_printcolumns(const easycsv *csv)
{
  return csv->_priv->cols;
}
 
int
_easycsv_rows(_easycsv *_priv, const EASYCSV_MODE mode)
{
  // no need to check _priv for NULL

  if (_easycsv_rewind(_priv, mode) < 0) return -1;

  int rows = 1;
  char c;

  /* Go through each character in the file and count the number of \n
     in it */
  while ((c = fgetc(_priv->file)) != EOF) {
    if (c == '\n') rows++;
  }

  return rows;
}

int
_easycsv_columns(_easycsv *_priv, const EASYCSV_MODE mode)
{
  // no need to check _priv for NULL
  
  /* Prepare it for reading */
  if (_easycsv_rewind(_priv, mode) < 0) return -1;
  
  /*
  1. check if empty file
  2. check if only one column -> 0 commas
  3. if >1 column, n commas = n+1 columns
  */

  unsigned int col = 1;
  char c;

  while ((c = fgetc(_priv->file)) != '\n') {
    if (c == ',') col++;
  }

  return col;
}

const char*
easycsv_readcolumnvalue(const easycsv *csv, const char *col, const unsigned int row)
{
  if (_easycsv_checkcsvandstring_one(csv, col) < 0) return NULL;
  
  if (row > csv->_priv->rows) {
    _easycsv_printerror(csv->_priv, EASYCSV_OVERMAXROW);
    return NULL;
  }

  int i = _easycsv_getcolumn(csv, col);
  if (i < 1) {
    _easycsv_printerror(csv->_priv, EASYCSV_COLNUMFAIL);
    return NULL;
  }

  return easycsv_readvalue(csv, i, row);
}

const char*
easycsv_readvalue(const easycsv *csv, const unsigned int col, const unsigned int row)
{
  if (row == 0) {
    _easycsv_printerror(csv->_priv, EASYCSV_ZEROROW);
    return NULL;
  }
  
  if (col == 0) {
    _easycsv_printerror(csv->_priv, EASYCSV_ZEROCOL);
    return NULL;
  }
  
  char *str = _easycsv_getrow(csv, row);
  if (str == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_ROWNOTEXIST);
    return NULL;
  }
  /*
#ifdef EASYCSV_DEBUG
  printf("[%i] rv_col: %i\nstr: %s\n", clock() - csv->_priv->start, col, str);
#endif
  */
  /* Return if first col */
  if (col == 1) {
    size_t st = strcspn(str, ",");
    if (st == 0) {
      free(str);
      return NULL;
    }	
    char *pch = malloc(st);
    strncpy(pch, str, st);
    free(str);
    return pch;
  }

  /* Get first occurance of comma in str,
     the first value is ommited but not the comma */
  char *pch = strpbrk(str, ",");

  /* Repeat until desired col is found */
  for (int i = 2; i < col; i++) { 
    pch = strpbrk(pch + 1, ",");
  }

  /* Get span from start of string to first occurence of comma */
  size_t st = strcspn(pch + 1, ",");

  /* If 0, no string exists! */
  if (st == 0) {
    free(str);
    return NULL;
  }
  
  char *val = malloc(st + 1);
  strncpy(val, pch + 1, st);
  strncat(val, "\0", 1);
  free(str);
  
  return val;
}

/* PRIVATE FUNCTIONS */

/*
static int _easycsv_checkmode(struct easycsv *csv, const char mode)
{
  if (strchr(csv->mode, mode) == NULL)
  {
    return -1;
  }
}
*/

int
_easycsv_update(easycsv *csv)
{
  if (csv == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_NULLCSV);
    return -1;
  }
  
  /* Set temp file to read binary */
  if (freopen(csv->_priv->tmpfp, "rb", csv->_priv->temp) == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_REOPENFAIL);
    easycsv_free(csv);
    return -1;
  }

  /* Set file to write binary */
  if (freopen(csv->_priv->fp, "wb", csv->_priv->file) == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_REOPENFAIL);
    easycsv_free(csv);
    return -1;
  }
  
  char buf[BUFSIZ];
  size_t size;    
  while (size = fread(buf, 1, BUFSIZ, csv->_priv->temp)) {
    fwrite(buf, 1, size, csv->_priv->file);
  }

  /* Set temp file back to write */
  if (freopen(csv->_priv->tmpfp, "w", csv->_priv->temp) == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_REOPENFAIL);
    easycsv_free(csv);
    return -1;
  }

  /* Set file back to read */
  if (freopen(csv->_priv->fp, "r", csv->_priv->file) == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_REOPENFAIL);
    easycsv_free(csv);
    return -1;
  }

  return 0;
}

char*
_easycsv_getrow(const easycsv *csv, const unsigned int row)
{
  if (csv == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_NULLCSV);
    return NULL;
  }
  
  if (row > csv->_priv->rows) {
    _easycsv_printerror(csv->_priv, EASYCSV_OVERMAXROW);
    return NULL;
  }

  if (row == 0) {
    _easycsv_printerror(csv->_priv, EASYCSV_ZEROROW);
    return NULL;
  }

  /* Allocate memory */
  char *str = malloc(BUFSIZ);

  /* Set file pointer to start */
  rewind(csv->_priv->file);
  
  for (int i = 1; i < row; i++)
  {
    /* skip until row is reached */
    fscanf(csv->_priv->file, "%*[^\n]\n", NULL);
  }

  /* Grab the row and store it in str */
  fscanf(csv->_priv->file, "%s\n", str);

  // printf("row: %s\n", str);
  
  return str;
}

int
_easycsv_rewind(_easycsv *_priv, const EASYCSV_MODE mode)
{  
  /* Check if empty file */
  if (fscanf(_priv->file, "\n") == EOF) {
    _easycsv_printerror(_priv, EASYCSV_EMPTYCSV);
    return -1;
  }
  
  /* Check if file is readable */
  if (mode != EASYCSV_R) {
    _easycsv_printerror(_priv, EASYCSV_UNREADABLE);
    return -1;
  }

  /* Set file pointer to the start */
  rewind(_priv->file);

  return 0;
}

int
_easycsv_getcolumn(const easycsv *csv, const char *col)
{
  if (_easycsv_checkcsvandstring_one(csv, col) < 0) return -1;

  /* Grab str of row 1 */
  char *firstrow = _easycsv_getrow(csv, 1);  
  
  if (firstrow == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_ROWNOTEXIST);
    return -1;
  }
  
  unsigned int commas = 0;

  // printf("FIRST COLUMN: %s\n", firstrow);

  /* Find first occurance of col in firstrow */
  char *str = strstr(firstrow, col);

  if (str == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_COLNOTEXIST);
    return -1;
  }

  /* Count numbers of commas following str */
  char *c = strpbrk(str, ",");
  while (c != NULL) {
    commas++;
    c = strpbrk(c + 1, ",");
  }

  /* no need to free c as it is already NULL at this point */
  // free((char*) str); apparently invalid pointer
  
  // printf("ROW: %i\nCOL: %i\n", row, csv->_priv->cols - commas);
  /*
#ifdef EASYCSV_DEBUG
  printf("[%i] rcv_commas: %i\n", clock() - csv->_priv->start, commas);
#endif
  */
  free(firstrow);

  return csv->_priv->cols - commas;
}

/*
int _easycsv_checkifvalue(struct easycsv *csv, const int col, const int row)
{
  const char *rowstr = _easycsv_getrow(csv, row);
  
  return 0;
}

char *_easycsv_getvalueinrow(const int col, const char *row)
{
  char *pbrk = strchr(row, ',');
  for (unsigned int i = 1; i < col; i++) {
    
  }  
}
*/

void
_easycsv_printerror(const _easycsv *_priv, const EASYCSV_ERROR error)
{ 
  switch (_priv->error) {
  case EASYCSV_ERROROFF: return;
  case EASYCSV_ERRORSTDOUT: _easycsv_geterror(_priv, error, stdout); break;
  case EASYCSV_ERRORSTDERR: 
  default: _easycsv_geterror(_priv, error, stderr); return;
  }
}

void
_easycsv_geterror(const _easycsv *_priv, const EASYCSV_ERROR error, FILE *fs)
{
#ifdef EASYCSV_DEBUG
  fprintf(stderr, "[%i] ", clock() - _priv->start);
#endif
  
  fputs("easycsv: ", fs);
  
  switch (error) {
  case EASYCSV_NOERROR: fputs("no error", fs); break;
  case EASYCSV_NULLCSV: fputs("easycsv pointer is NULL", fs); break;
  case EASYCSV_NULLPTR: fputs("pointer is NULL", fs); break;
  case EASYCSV_EMPTYSTRING: fputs("string is empty", fs); break;
  case EASYCSV_OVERMAXROW: fprintf(fs, "int exceeds row limit %i", _priv->rows); break;
  case EASYCSV_OVERMAXCOL: fprintf(fs, "int exceeds column limit %i", _priv->cols); break;
  case EASYCSV_ZEROROW: fputs("parameterised row number is zero", fs); break;
  case EASYCSV_ZEROCOL: fputs("parameterised column number is zero", fs); break;
    
  case EASYCSV_UNKNOWNMODE: fputs("unknown file IO mode", fs); break;
  case EASYCSV_OPENFAIL: fputs("failed to open file", fs); break;
  case EASYCSV_REOPENFAIL: fputs("failed to reopen file", fs); break;
  case EASYCSV_EMPTYCSV: fputs("CSV file is empty", fs); break;
  case EASYCSV_UNWRITABLE: fputs("CSV file is not in a writable mode", fs); break;
  case EASYCSV_UNREADABLE: fputs("CSV file is not in a readable mode", fs); break;
  case EASYCSV_UPDATEFAIL: fputs("CSV file has failed to update", fs); break;
  case EASYCSV_FILEPTRFAIL: fputs("failed to move FILE pointer", fs); break;

  case EASYCSV_ROWNOTEXIST: fputs("given row does not exist", fs); break;
  case EASYCSV_COLNOTEXIST: fputs("given column does not exist", fs); break;

  case EASYCSV_PUSHCOLFAIL: fputs("failed to push value under column", fs); break;
  case EASYCSV_COLNUMFAIL: fputs("failed to determine the column number of a value in the first row", fs); break;
  default: fputs("unknown error, easycsv* is possibly NULL", fs); break;
  }

  if (_priv->fp != NULL) {
    fprintf(fs, " in %s", _priv->fp);
  }

  fputc('\n', fs);
}

int
_easycsv_checkcsvandstring_one(const easycsv *csv, const char *one)
{
  if (csv == NULL) {
    _easycsv_printerror(csv->_priv, EASYCSV_NULLCSV);
    return -1;
  }

  if ((one == NULL) || (one[0] == '\0')) {
    _easycsv_printerror(csv->_priv, EASYCSV_EMPTYSTRING);
    return -1;
  }

  return 0;
}

int
  _easycsv_checkcsvandstringtwo(const easycsv *csv, const char *one, const char *two)
{
  if (_easycsv_checkcsvandstring_one(csv, one) < 0) return -1;

  if ((two == NULL) || (two[0] == '\0')) {
    _easycsv_printerror(csv->_priv, EASYCSV_EMPTYSTRING);
    return -1;
  }

  return 0;
}