#  test-pipes.tcl

# !/bin/sh
# the next line restarts using tclsh \
exec tclsh "$0" "$@"

package require -exact Gnocl 0.9.96

proc chess {} {
                
        global done
        global turn
        global pipe
        global ent
        global txt
        
        # simple GUI
        set box [gnocl::vBox]
        set ent [gnocl::entry -onActivate { pipewrite $pipe %t }]
        set txt [gnocl::text -baseFont {mono} -editable 0]
        set lab [gnocl::label -text "White to move." -variable msg -align left]

        $box add $ent
        $box add $txt -fill 1 -expand 1
        $box add $lab
        gnocl::window -child $box -setSize 0.25 -title gnocl-gnuchess-gui
        
        set cmd gnuchess        
        set turn 0
        
        set pipe [open "|$cmd" RDWR]

    fconfigure $pipe -buffering full -blocking 0
    fileevent $pipe readable [list piperead $pipe]
    
    vwait done ;# include this else the script will not run
    
}

proc pipewrite {pipe opt} { 

        global txt
        global turn
        global ent
        $txt insert end "[incr turn].\t$opt\t"
        $ent set ""
        $ent configure -sensitive 0
        puts $pipe $opt
        flush $pipe
}


proc piperead {pipe} { 

        global done
        global txt
        global buff
        global msg
        global ent
        
        if { [eof $pipe] } {
                catch {close $pipe}
                set done 1
                return
        }

        gets $pipe line
                
        if { [string first "My move is" $line ] == 0 } {
                $txt insert end "[lindex $line end]\n"
                set msg "White to move."
                $ent configure -sensitive 1
                $ent grabFocus
        }
        
        if { [string first "Thinking" $line ] == 0 } {
                set msg $line
        } 

}

chess