#include <grass/dbmi.h>
#include <grass/datetime.h>
#include "odbc.h"
#include "globals.h"
#include "proto.h"
#include <stdio.h>

int set_column_type ( dbColumn *column, int otype );   

int db__driver_describe_table (table_name, table)
    dbString *table_name;
    dbTable **table;
{
    char        *name = NULL;
    SQLINTEGER  err;    
    SQLRETURN   ret;
    cursor      *c;
    char        s[100];
    char        msg[OD_MSG];
    char        *emsg;

    /* allocate cursor */
    c = alloc_cursor();
    if (c == NULL)
        return DB_FAILED;

    name = db_get_string (table_name);

    SQLSetStmtAttr( c->stmt, SQL_MAX_ROWS, (SQLPOINTER *)1, 0);

    sprintf(s,"select * from %s", name);

    ret = SQLExecDirect(c->stmt,s,SQL_NTS); 
    if ((ret != SQL_SUCCESS) && (ret != SQL_SUCCESS_WITH_INFO))
    {
        SQLGetDiagRec(SQL_HANDLE_STMT, c->stmt, 1, NULL, &err, msg, sizeof(msg), NULL);        
	G_asprintf(&emsg, "SQLExecDirect():\n%s\n%s (%d)\n",s,msg,err);
        report_error(emsg);
        return DB_FAILED;
    }
    
    describe_table(c->stmt, table);

    free_cursor (c);

    /* set the table name */
    db_set_table_name (*table, name);

    /* set the table description */
    db_set_table_description(*table, "");

    /* 
    db_set_table_delete_priv_granted (*table);
    db_set_table_delete_priv_not_granted (*table);
    db_set_table_insert_priv_granted (*table);
    db_set_table_insert_priv_not_granted (*table);
    */

    return DB_OK;
}


int
describe_table(stmt, table)
    SQLHSTMT  stmt;
    dbTable **table;
{
    dbColumn     *column;       
    int          col, intval;
    SQLUSMALLINT ncols;      
    SQLRETURN    ret;  
    SQLCHAR      charval[100];

    /* get the number of colummns */
    ret = SQLNumResultCols( stmt, &ncols);
    if ((ret != SQL_SUCCESS) && (ret != SQL_SUCCESS_WITH_INFO))
    {
	report_error("SQLNumResultCols()");
	return DB_FAILED;
    }  

    /* allocate a table structure to correspond to our system descriptor */
    if (!(*table = db_alloc_table(ncols))) {
	return DB_FAILED;
    }

    /* Get col names and attributes */
    for (col=0; col < ncols; col++)
    {    
        column = db_get_table_column (*table, col);

        SQLColAttribute( stmt, col+1, SQL_COLUMN_NAME, charval, sizeof(charval), NULL, NULL );
        db_set_column_name (column, charval);   

	/* label(title) is not description, but I did not found better attribute and it can say something about column */
        SQLColAttribute( stmt, col+1, SQL_COLUMN_LABEL, charval, sizeof(charval), NULL, NULL );
        db_set_column_description(column, charval);

        SQLColAttribute( stmt, col+1, SQL_COLUMN_LENGTH , NULL, 0, NULL, &intval );
        db_set_column_length (column, intval);

        SQLColAttribute( stmt, col+1, SQL_COLUMN_PRECISION , NULL, 0, NULL, &intval );
        db_set_column_precision (column, intval);

        SQLColAttribute( stmt, col+1, SQL_COLUMN_SCALE , NULL, 0, NULL, &intval ); 
        db_set_column_scale (column, intval);

        SQLColAttribute( stmt, col+1, SQL_COLUMN_NULLABLE , NULL, 0, NULL, &intval );  
        if ( intval == SQL_NULLABLE )
            db_set_column_null_allowed (column);
        else
            db_unset_column_null_allowed (column);

	/*
        db_set_column_select_priv_not_granted (column);
	db_set_column_select_priv_not_granted (column);
	db_set_column_update_priv_granted (column);
	db_set_column_update_priv_not_granted (column);
	*/

	/* because set_column_type() uses other attributes (length, precision,...) must be called at the end */
        SQLColAttribute( stmt, col+1, SQL_COLUMN_TYPE,  NULL, 0, NULL, &intval );
        set_column_type (column, intval);
	db_set_column_host_type (column, intval);   	

	/* set default value after we recognized type */
	/*
	db_set_column_has_defined_default_value(column);
	db_set_column_has_undefined_default_value(column);
	db_set_column_use_default_value(column);
	db_unset_column_use_default_value(column);
	*/
	/* and set column.defaultValue */
    }															

    return DB_OK;
}

int 
set_column_type ( column, otype)
    dbColumn *column;
    int otype;
{
    int dbtype;
    
    /* determine the DBMI datatype from ODBC type */
    switch ( otype )
    {  
    /* numbers */
    case SQL_INTEGER:
        dbtype = DB_SQL_TYPE_INTEGER;
        break;
    case SQL_SMALLINT:
        dbtype = DB_SQL_TYPE_SMALLINT;
        break;    
    case SQL_REAL:
    	    dbtype = DB_SQL_TYPE_REAL;    
	break;
    case SQL_DOUBLE:
        dbtype = DB_SQL_TYPE_DOUBLE_PRECISION;
        break;
    case SQL_FLOAT:
        if (db_get_column_precision(column) == 24 )
    	    dbtype = DB_SQL_TYPE_REAL;    
        else
            dbtype = DB_SQL_TYPE_DOUBLE_PRECISION; /* precision == 53 */
	break;
    case SQL_DECIMAL:
        dbtype = DB_SQL_TYPE_DECIMAL;
        break;
    case SQL_NUMERIC:
        dbtype = DB_SQL_TYPE_NUMERIC;
        break;

    /* strings */
    case SQL_CHAR:
        dbtype = DB_SQL_TYPE_CHARACTER;
        break;   
    case SQL_VARCHAR:
        dbtype = DB_SQL_TYPE_CHARACTER;
	break;
    case SQL_LONGVARCHAR:
        dbtype = DB_SQL_TYPE_CHARACTER;
	break;	

    /* date & time */
    case SQL_DATE:
	dbtype = DB_SQL_TYPE_DATE;
        break;  
    case SQL_TYPE_DATE:
	dbtype = DB_SQL_TYPE_DATE;
        break;	
    case SQL_TIME:
	dbtype = DB_SQL_TYPE_TIME;
        break;  
    case SQL_TYPE_TIME:
	dbtype = DB_SQL_TYPE_TIME;
        break;
    case SQL_TIMESTAMP:
	dbtype = DB_SQL_TYPE_TIMESTAMP;
        break;
    case SQL_TYPE_TIMESTAMP:
	dbtype = DB_SQL_TYPE_TIMESTAMP;
        break;

    default:
        dbtype = DB_SQL_TYPE_UNKNOWN;
        break;
    }
	 
    db_set_column_sqltype (column, dbtype);
    return DB_OK;
}