/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */


/* Copy data from a textfile to table */

#include "mysql_priv.h"
#include <my_dir.h>
#include <m_ctype.h>

class READ_INFO {
  File	file;
  byte	*buffer,			/* Buffer for read text */
	*end_of_buff;			/* Data in bufferts ends here */
  uint	buff_length,			/* Length of buffert */
	max_length;			/* Max length of row */
  char	*field_term_ptr,*line_term_ptr,*line_start_ptr,*line_start_end;
  uint	field_term_length,line_term_length,enclosed_length;
  int	field_term_char,line_term_char,enclosed_char,escape_char;
  int	*stack,*stack_pos;
  bool	found_end_of_line,start_of_line,eof;
  IO_CACHE cache;
  NET *io_net;

public:
  bool error,line_cuted,found_null,enclosed;
  byte	*row_start,			/* Found row starts here */
	*row_end;			/* Found row ends here */

  READ_INFO(File file,uint tot_length,
	    String &field_term,String &line_start,String &line_term,
	    String &enclosed,int escape,bool get_it_from_net, bool is_fifo);
  ~READ_INFO();
  int read_field();
  int read_fixed_length(void);
  int next_line(void);
  char unescape(char chr);
  int terminator(char *ptr,uint length);
  bool find_start_of_fields();
};

static int read_fixed_length(THD *thd,COPY_INFO &info,TABLE *table,
			     List<Item> &fields, READ_INFO &read_info);
static int read_sep_field(THD *thd,COPY_INFO &info,TABLE *table,
			  List<Item> &fields, READ_INFO &read_info,
			  String &enclosed);


int mysql_load(THD *thd,sql_exchange *ex,TABLE_LIST *table_list,
	       List<Item> &fields, enum enum_duplicates handle_duplicates,
	       bool read_file_from_client,thr_lock_type lock_type)
{
  char name[FN_REFLEN];
  File file;
  TABLE *table;
  int error;
  uint save_skip_lines = ex->skip_lines;
  String *field_term=ex->field_term,*escaped=ex->escaped,
    *enclosed=ex->enclosed;
  bool is_fifo=0;
  DBUG_ENTER("mysql_load");

  if (escaped->length() > 1 || enclosed->length() > 1)
  {
    my_message(ER_WRONG_FIELD_TERMINATORS,ER(ER_WRONG_FIELD_TERMINATORS),
	       MYF(0));
    DBUG_RETURN(-1);
  }

  if (!(table = open_ltable(thd,table_list,lock_type)))
    DBUG_RETURN(-1);
  if (!fields.elements)
  {
    Field **field;
    for (field=table->field; *field ; field++)
      fields.push_back(new Item_field(*field));
  }
  else
  {						// Part field list
    thd->dupp_field=0;
    if (setup_fields(thd,table_list,fields,1,0) < 0)
      DBUG_RETURN(-1);
    if (thd->dupp_field)
    {
      my_error(ER_FIELD_SPECIFIED_TWICE, MYF(0), thd->dupp_field->field_name);
      DBUG_RETURN(-1);
    }
  }

  uint tot_length=0;
  bool use_blobs=0,use_timestamp=0;
  List_iterator<Item> it(fields);

  Item_field *field;
  while ((field=(Item_field*) it++))
  {
    if (field->field->flags & BLOB_FLAG)
    {
      use_blobs=1;
      tot_length+=256;				// Will be extended if needed
    }
    else
      tot_length+=field->field->field_length;
    if (!field_term->length() && !(field->field->flags & NOT_NULL_FLAG))
      field->field->set_notnull();
    if (field->field == table->timestamp_field)
      use_timestamp=1;
  }
  if (use_blobs && !ex->line_term->length() && !field_term->length())
  {
    my_message(ER_BLOBS_AND_NO_TERMINATED,ER(ER_BLOBS_AND_NO_TERMINATED),
	       MYF(0));
    DBUG_RETURN(-1);
  }

  /* We can't give an error in the middle when using LOCAL files */
  if (read_file_from_client && handle_duplicates == DUP_ERROR)
    handle_duplicates=DUP_IGNORE;

  if (read_file_from_client && (thd->client_capabilities & CLIENT_LOCAL_FILES))
  {
    char tmp [FN_REFLEN+1],*end;
    DBUG_PRINT("info",("reading local file"));
    tmp[0] = (char) 251;				/* NULL_LENGTH */
    end=strnmov(tmp+1,ex->file_name,sizeof(tmp)-2);
    (void) my_net_write(&thd->net,tmp,(uint) (end-tmp));
    (void) net_flush(&thd->net);
    file = -1;
  }
  else
  {
    read_file_from_client=0;
#ifdef DONT_ALLOW_FULL_LOAD_DATA_PATHS
    ex->file_name+=dirname_length(ex->file_name);
#endif
    if (!dirname_length(ex->file_name) &&
	strlen(ex->file_name)+strlen(mysql_data_home)+strlen(thd->db)+3 <
	FN_REFLEN)
    {
      (void) sprintf(name,"%s/%s/%s",mysql_data_home,thd->db,ex->file_name);
      unpack_filename(name,name);		/* Convert to system format */
    }
    else
    {
      unpack_filename(name,ex->file_name);
#ifndef __WIN__
      MY_STAT stat_info;
      if (!my_stat(name,&stat_info,MYF(MY_WME)))
	DBUG_RETURN(-1);
      
      // the file must be:
      if (!((stat_info.st_mode & S_IROTH) == S_IROTH &&  // readable by others
	    (stat_info.st_mode & S_IFLNK) != S_IFLNK && // and not a symlink
	    ((stat_info.st_mode & S_IFREG) == S_IFREG ||
	     (stat_info.st_mode & S_IFIFO) == S_IFIFO)))
      {
	my_error(ER_TEXTFILE_NOT_READABLE,MYF(0),name);
	DBUG_RETURN(-1);
      }
      if ((stat_info.st_mode & S_IFIFO) == S_IFIFO)
	is_fifo = 1;
#endif
    }
    if ((file=my_open(name,O_RDONLY,MYF(MY_WME))) < 0)
      DBUG_RETURN(-1);
  }

  COPY_INFO info;
  bzero((char*) &info,sizeof(info));
  info.handle_duplicates=handle_duplicates;
  info.escape_char=escaped->length() ? (*escaped)[0] : INT_MAX;

  READ_INFO read_info(file,tot_length,*field_term,
		      *ex->line_start, *ex->line_term, *enclosed,
		      info.escape_char, read_file_from_client, is_fifo);
  if (read_info.error)
  {
    if	(file >= 0)
      my_close(file,MYF(0));			// no files in net reading
    DBUG_RETURN(-1);				// Can't allocate buffers
  }

  restore_record(table,2);

  thd->count_cuted_fields=1;			/* calc cuted fields */
  thd->cuted_fields=0L;
  if (ex->line_term->length() && field_term->length())
  {
    while (ex->skip_lines--)
    {
      if (read_info.next_line())
	break;
    }
  }
  if (!(error=test(read_info.error)))
  {
    uint save_time_stamp=table->time_stamp;
    if (use_timestamp)
      table->time_stamp=0;
    table->next_number_field=table->found_next_number_field;
    VOID(table->file->extra(HA_EXTRA_WRITE_CACHE));
    table->file->deactivate_non_unique_index((ha_rows) 0);
    table->copy_blobs=1;
    if (!field_term->length() && !enclosed->length())
      error=read_fixed_length(thd,info,table,fields,read_info);
    else
      error=read_sep_field(thd,info,table,fields,read_info,*enclosed);
    if (table->file->extra(HA_EXTRA_NO_CACHE) ||
	table->file->activate_all_index(thd))
      error=1; /* purecov: inspected */
      
    table->time_stamp=save_time_stamp;
    table->next_number_field=0;
    if (thd->lock)
    {
      mysql_unlock_tables(thd, thd->lock);
      thd->lock=0;
    }
  }
  if  (file >= 0) my_close(file,MYF(0));
  free_blobs(table);				/* if pack_blob was used */
  table->copy_blobs=0;
  thd->count_cuted_fields=0;			/* Don`t calc cuted fields */
  if (error)
    DBUG_RETURN(-1);				// Error on read
  sprintf(name,ER(ER_LOAD_INFO),info.records,info.deleted,
	  info.records-info.copied,thd->cuted_fields);
  send_ok(&thd->net,info.copied+info.deleted,0L,name);
  mysql_update_log.write(thd,thd->query,thd->query_length);
  
  if (!read_file_from_client)
  {
    ex->skip_lines = save_skip_lines; 
    Load_log_event qinfo(thd, ex, table->table_name, fields, handle_duplicates);
    mysql_bin_log.write(&qinfo);
  }
  DBUG_RETURN(0);
}


/****************************************************************************
** Read of rows of fixed size + optional garage + optonal newline
****************************************************************************/

static int
read_fixed_length(THD *thd,COPY_INFO &info,TABLE *table,List<Item> &fields,
		  READ_INFO &read_info)
{
  List_iterator<Item> it(fields);
  Item_field *sql_field;
  DBUG_ENTER("read_fixed_length");

  /* No fields can be null in this format. mark all fields as not null */
  while ((sql_field= (Item_field*) it++))
      sql_field->field->set_notnull();

  while (!read_info.read_fixed_length())
  {
    if (thd->killed)
    {
      my_error(ER_SERVER_SHUTDOWN,MYF(0));
      DBUG_RETURN(1);
    }
    it.rewind();
    byte *pos=read_info.row_start;
#ifdef HAVE_purify
    read_info.row_end[0]=0;
#endif
    while ((sql_field= (Item_field*) it++))
    {
      Field *field=sql_field->field;
      if (pos == read_info.row_end)
      {
	thd->cuted_fields++;			/* Not enough fields */
	field->reset();
      }
      else
      {
	uint length;
	byte save_chr;
	if ((length=(uint) (read_info.row_end-pos)) >
	    field->field_length)
	  length=field->field_length;
	save_chr=pos[length]; pos[length]='\0'; // Safeguard aganst malloc
	field->store((char*) pos,length);
	pos[length]=save_chr;
	if ((pos+=length) > read_info.row_end)
	  pos= read_info.row_end;	/* Fills rest with space */
      }
    }
    if (pos != read_info.row_end)
      thd->cuted_fields++;			/* To long row */
    if (write_record(table,&info))
      DBUG_RETURN(1);
    if (table->next_number_field)
      table->next_number_field->reset();	// Clear for next record
    if (read_info.next_line())			// Skipp to next line
      break;
    if (read_info.line_cuted)
      thd->cuted_fields++;			/* To long row */
  }
  DBUG_RETURN(test(read_info.error));
}



static int
read_sep_field(THD *thd,COPY_INFO &info,TABLE *table,
	       List<Item> &fields, READ_INFO &read_info,
	       String &enclosed)
{
  List_iterator<Item> it(fields);
  Item_field *sql_field;
  uint enclosed_length;
  DBUG_ENTER("read_sep_field");

  enclosed_length=enclosed.length();

  for (;;it.rewind())
  {
    if (thd->killed)
    {
      my_error(ER_SERVER_SHUTDOWN,MYF(0));
      DBUG_RETURN(1);
    }
    while ((sql_field=(Item_field*) it++))
    {
      uint length;
      byte *pos;

      if (read_info.read_field())
	break;
      pos=read_info.row_start;
      length=(uint) (read_info.row_end-pos);
      Field *field=sql_field->field;

      if (!read_info.enclosed &&
	  (enclosed_length && length == 4 && !memcmp(pos,"NULL",4)) ||
	  (length == 1 && read_info.found_null))
      {
	field->reset();
	field->set_null();
	if (!field->maybe_null())
	{
	  if (field->type() == FIELD_TYPE_TIMESTAMP)
	    ((Field_timestamp*) field)->set_time();
	  else
	    thd->cuted_fields++;
	}
	continue;
      }
      field->set_notnull();
      read_info.row_end[0]=0;			// Safe to change end marker
      field->store((char*) read_info.row_start,length);
    }
    if (read_info.error)
      break;
    if (sql_field)
    {						// Last record
      if (sql_field == (Item_field*) fields.head())
	break;
      for ( ; sql_field ; sql_field=(Item_field*) it++)
      {
	sql_field->field->set_null();
	sql_field->field->reset();
	thd->cuted_fields++;
      }
    }
    if (write_record(table,&info))
      DBUG_RETURN(1);
    if (table->next_number_field)
      table->next_number_field->reset();	// Clear for next record
    if (read_info.next_line())			// Skipp to next line
      break;
    if (read_info.line_cuted)
      thd->cuted_fields++;			/* To long row */
  }
  DBUG_RETURN(test(read_info.error));
}


/* Unescape all escape characters, mark \N as null */

char
READ_INFO::unescape(char chr)
{
  switch(chr) {
  case 'n': return '\n';
  case 't': return '\t';
  case 'r': return '\r';
  case 'b': return '\b';
  case '0': return 0;				// Ascii null
  case 'Z': return '\032';			// Win32 end of file
  case 'N': found_null=1;

    /* fall through */
  default:  return chr;
  }
}


	/* Read a line using buffering */
	/* If last line is empty (in line mode) then it isn't outputed */


READ_INFO::READ_INFO(File file_par, uint tot_length, String &field_term,
		     String &line_start, String &line_term,
		     String &enclosed_par, int escape, bool get_it_from_net,
		     bool is_fifo)
  :file(file_par),escape_char(escape)
{
  field_term_ptr=(char*) field_term.ptr();
  field_term_length= field_term.length();
  line_term_ptr=(char*) line_term.ptr();
  line_term_length= line_term.length();
  if (line_start.length() == 0)
  {
    line_start_ptr=0;
    start_of_line= 0;
  }
  else
  {
    line_start_ptr=(char*) line_start.ptr();
    line_start_end=line_start_ptr+line_start.length();
    start_of_line= 1;
  }
  /* If field_terminator == line_terminator, don't use line_terminator */
  if (field_term_length == line_term_length &&
      !memcmp(field_term_ptr,line_term_ptr,field_term_length))
  {
    line_term_length=0;
    line_term_ptr=(char*) "";
  }
  enclosed_char= (enclosed_length=enclosed_par.length()) ?
    (uchar) enclosed_par[0] : INT_MAX;
  field_term_char= field_term_length ? (uchar) field_term_ptr[0] : INT_MAX;
  line_term_char= line_term_length ? (uchar) line_term_ptr[0] : INT_MAX;
  error=eof=found_end_of_line=found_null=line_cuted=0;
  buff_length=tot_length;


  /* Set of a stack for unget if long terminators */
  uint length=max(field_term_length,line_term_length)+1;
  set_if_bigger(length,line_start.length());
  stack=stack_pos=(int*) sql_alloc(sizeof(int)*length);

  if (!(buffer=(byte*) my_malloc(buff_length+1,MYF(0))))
    error=1; /* purecov: inspected */
  else
  {
    end_of_buff=buffer+buff_length;
    if (init_io_cache(&cache,(get_it_from_net) ? -1 : file, 0,
		      (get_it_from_net) ? READ_NET :
		      (is_fifo ? READ_FIFO : READ_CACHE),0L,1,
		      MYF(MY_WME)))
    {
      my_free((gptr) buffer,MYF(0)); /* purecov: inspected */
      error=1;
    }
  }
}


READ_INFO::~READ_INFO()
{
  if (!error)
  {
    end_io_cache(&cache);
    my_free((gptr) buffer,MYF(0));
    error=1;
  }
}


#define GET (stack_pos != stack ? *--stack_pos : my_b_get(&cache))
#define PUSH(A) *(stack_pos++)=(A)


inline int READ_INFO::terminator(char *ptr,uint length)
{
  int chr=0;					// Keep gcc happy
  uint i;
  for (i=1 ; i < length ; i++)
  {
    if ((chr=GET) != *++ptr)
    {
      break;
    }
  }
  if (i == length)
    return 1;
  PUSH(chr);
  while (i-- > 1)
    PUSH((uchar) *--ptr);
  return 0;
}


int READ_INFO::read_field()
{
  int chr,found_enclosed_char;
  byte *to,*new_buffer;

  found_null=0;
  if (found_end_of_line)
    return 1;					// One have to call next_line

  /* Skipp until we find 'line_start' */

  if (start_of_line)
  {						// Skipp until line_start
    start_of_line=0;
    if (find_start_of_fields())
      return 1;
  }
  if ((chr=GET) == my_b_EOF)
  {
    found_end_of_line=eof=1;
    return 1;
  }
  to=buffer;
  if (chr == enclosed_char)
  {
    found_enclosed_char=enclosed_char;
    *to++=(byte) chr;				// If error
  }
  else
  {
    found_enclosed_char= INT_MAX;
    PUSH(chr);
  }

  for (;;)
  {
    while ( to < end_of_buff)
    {
      chr = GET;
#ifdef USE_MB
      if (use_mb(default_charset_info) &&
          my_ismbhead(default_charset_info, chr) &&
          to+my_mbcharlen(default_charset_info, chr) <= end_of_buff)
      {
	  uchar* p = (uchar*)to;
	  *to++ = chr;
	  int ml = my_mbcharlen(default_charset_info, chr);
	  int i;
	  for (i=1; i<ml; i++) {
	      chr = GET;
	      if (chr == my_b_EOF)
		  goto found_eof;
	      *to++ = chr;
	  }
	  if (my_ismbchar(default_charset_info,
                          (const char *)p,
                          (const char *)to))
	    continue;
	  for (i=0; i<ml; i++)
	    PUSH((uchar) *--to);
	  chr = GET;
      }
#endif
      if (chr == my_b_EOF)
	goto found_eof;
      if (chr == escape_char)
      {
	if ((chr=GET) == my_b_EOF)
	{
	  *to++= (byte) escape_char;
	  goto found_eof;
	}
	*to++ = (byte) unescape((char) chr);
	continue;
      }
#ifdef ALLOW_LINESEPARATOR_IN_STRINGS
      if (chr == line_term_char)
#else
      if (chr == line_term_char && found_enclosed_char == INT_MAX)
#endif
      {
	if (terminator(line_term_ptr,line_term_length))
	{					// Maybe unexpected linefeed
	  enclosed=0;
	  found_end_of_line=1;
	  row_start=buffer;
	  row_end=  to;
	  return 0;
	}
      }
      if (chr == found_enclosed_char)
      {
	if ((chr=GET) == found_enclosed_char)
	{					// Remove dupplicated
	  *to++ = (byte) chr;
	  continue;
	}
	// End of enclosed field if followed by field_term or line_term
	if (chr == my_b_EOF ||
	    chr == line_term_char && terminator(line_term_ptr,
						line_term_length))
	{					// Maybe unexpected linefeed
	  enclosed=1;
	  found_end_of_line=1;
	  row_start=buffer+1;
	  row_end=  to;
	  return 0;
	}
	if (chr == field_term_char &&
	    terminator(field_term_ptr,field_term_length))
	{
	  enclosed=1;
	  row_start=buffer+1;
	  row_end=  to;
	  return 0;
	}
	/* Copy the found '"' character */
	PUSH(chr);
	chr='"';
      }
      else if (chr == field_term_char && found_enclosed_char == INT_MAX)
      {
	if (terminator(field_term_ptr,field_term_length))
	{
	  enclosed=0;
	  row_start=buffer;
	  row_end=  to;
	  return 0;
	}
      }
      *to++ = (byte) chr;
    }
    /*
    ** We come here if buffer is too small. Enlarge it and continue
    */
    if (!(new_buffer=(byte*) my_realloc((char*) buffer,buff_length+1+IO_SIZE,
					MYF(MY_WME))))
      return (error=1);
    to=new_buffer + (to-buffer);
    buffer=new_buffer;
    buff_length+=IO_SIZE;
    end_of_buff=buffer+buff_length;
  }

found_eof:
  enclosed=0;
  found_end_of_line=eof=1;
  row_start=buffer;
  row_end=to;
  return 0;
}

/*
** One can't use fixed length with multi-byte charset **
*/
 
int READ_INFO::read_fixed_length()
{
  int chr;
  byte *to;
  if (found_end_of_line)
    return 1;					// One have to call next_line

  if (start_of_line)
  {						// Skipp until line_start
    start_of_line=0;
    if (find_start_of_fields())
      return 1;
  }

  to=row_start=buffer;
  while (to < end_of_buff)
  {
    if ((chr=GET) == my_b_EOF)
      goto found_eof;
    if (chr == escape_char)
    {
      if ((chr=GET) == my_b_EOF)
      {
	*to++= (byte) escape_char;
	goto found_eof;
      }
      *to++ =(byte) unescape((char) chr);
      continue;
    }
    if (chr == line_term_char)
    {
      if (terminator(line_term_ptr,line_term_length))
      {						// Maybe unexpected linefeed
	found_end_of_line=1;
	row_end=  to;
	return 0;
      }
    }
    *to++ = (byte) chr;
  }
  row_end=to;					// Found full line
  return 0;

found_eof:
  found_end_of_line=eof=1;
  row_start=buffer;
  row_end=to;
  return to == buffer ? 1 : 0;
}


int READ_INFO::next_line()
{
  line_cuted=0;
  start_of_line= line_start_ptr != 0;
  if (found_end_of_line || eof)
  {
    found_end_of_line=0;
    return eof;
  }
  found_end_of_line=0;
  if (!line_term_length)
    return 0;					// No lines
  for (;;)
  {
    int chr = GET;
#ifdef USE_MB
   if (use_mb(default_charset_info) && my_ismbhead(default_charset_info, chr))
   {
       for (int i=1;
            chr != my_b_EOF && i<my_mbcharlen(default_charset_info, chr);
            i++)
	   chr = GET;
       if (chr == escape_char)
	   continue;
   }
#endif
   if (chr == my_b_EOF)
   {
      eof=1;
      return 1;
    }
    if (chr == escape_char)
    {
      line_cuted=1;
      if (GET == my_b_EOF)
	return 1;
      continue;
    }
    if (chr == line_term_char && terminator(line_term_ptr,line_term_length))
      return 0;
    line_cuted=1;
  }
}


bool READ_INFO::find_start_of_fields()
{
  int chr;
 try_again:
  do
  {
    if ((chr=GET) == my_b_EOF)
    {
      found_end_of_line=eof=1;
      return 1;
    }
  } while ((char) chr != line_start_ptr[0]);
  for (char *ptr=line_start_ptr+1 ; ptr != line_start_end ; ptr++)
  {
    chr=GET;					// Eof will be checked later
    if ((char) chr != *ptr)
    {						// Can't be line_start
      PUSH(chr);
      while (--ptr != line_start_ptr)
      {					// Restart with next char
	PUSH((uchar) *ptr);
      }
      goto try_again;
    }
  }
  return 0;
}