! Copyright (C) 2007 Berlin Brown, 2008 Doug Coleman.
! See http://factorcode.org/license.txt for license.
! Adapted from mysql.h and mysql.c
! Tested with MySQL version - 5.0.24a
USING: kernel alien io prettyprint sequences
namespaces arrays math db.mysql.ffi system ;
IN: db.mysql.lib

SYMBOL: my-conn

TUPLE: mysql-db handle host user password db port ;
TUPLE: mysql-statement ;
TUPLE: mysql-result-set ;

: new-mysql ( -- conn )
    f mysql_init ;
    
: mysql-error-string ( mysql-connection -- str )
    mysql-db-handle mysql_error ;

: mysql-error ( mysql -- )
    mysql-error-string throw ;

: mysql-connect ( mysql-connection -- )
    init-mysql swap
    [ set-mysql-connection-mysqlconn ] 2keep
    [ mysql-connection-host ] keep
    [ mysql-connection-user ] keep
    [ mysql-connection-password ] keep
    [ mysql-connection-db ] keep
    [ mysql-connection-port f 0 mysql_real_connect ] keep
    [ set-mysql-connection-handle ] keep 
    dup mysql-connection-handle 
    [ connect-error-msg throw ] unless ;

! =========================================================
! Low level mysql utility definitions
! =========================================================

: (mysql-query) ( mysql-connection query -- ret )
    >r mysql-connection-mysqlconn r> mysql_query ;

: (mysql-result) ( mysql-connection -- ret )
    [ mysql-connection-mysqlconn mysql_use_result ] keep 
    [ set-mysql-connection-resulthandle ] keep ;
    
: (mysql-affected-rows) ( mysql-connection -- n )
    mysql-connection-mysqlconn mysql_affected_rows ;

: (mysql-free-result) ( mysql-connection -- )
    mysql-connection-resulthandle drop ;

: (mysql-row) ( mysql-connection -- row )
    mysql-connection-resulthandle mysql_fetch_row ;

: (mysql-num-cols) ( mysql-connection -- n )
    mysql-connection-resulthandle mysql_num_fields ;
   
: mysql-char*-nth ( index object -- str )
    #! Utility based on 'char*-nth' to perform an additional sanity check on the value
    #! extracted from the array of strings.
    void*-nth [ alien>char-string ] [ "" ] if* ;
        
: mysql-row>seq ( object n -- seq )
    [ swap mysql-char*-nth ] map-with ;
    
: (mysql-result>seq) ( seq -- seq )
    my-conn get (mysql-row) dup [       
        my-conn get (mysql-num-cols) mysql-row>seq
        over push
        (mysql-result>seq)
    ] [ drop ] if 
    ! Perform needed cleanup on fetched results
    my-conn get (mysql-free-result) ;
            
! =========================================================
!  Public Word Definitions
! =========================================================


: mysql-query ( query -- ret )
    >r my-conn get r> (mysql-query) drop
    my-conn get (mysql-result) ;

: mysql-command ( query -- n )
    mysql-query drop
    my-conn get (mysql-affected-rows) ;

: with-mysql ( host user password db port quot -- )
    [ 
        >r <mysql-connection> my-conn set 
            my-conn get mysql-connect drop r> 
        [ my-conn get mysql-close ] cleanup
    ] with-scope ; inline