proc multiZone_open { filename } {
# 1 means success
    global IMAGE_DISPLAY_WIN ZONING_SCALE_FACTOR DISPLAY_IMAGE XV xvprocess \
	    multiZone_display_open
    
    set open 1
    
    if { $multiZone_display_open == $open } {
	focus .zoning_window
    } else {
	
	toplevel .zoning_window
	init_zoning_display .zoning_window
    }
	
        
#   puts stdout "Opening $filename"
    page_open $filename
# Scale image to display    
    set ZONING_SCALE_FACTOR .50
#[ max [expr 800.0/[get_page_height]] \
#		[expr 800/[get_page_width]] ]

#   puts stdout "Done putting into page structure"
    if { 1 }  {
	set display_height [expr $ZONING_SCALE_FACTOR * [get_page_height]]
	set display_width [expr $ZONING_SCALE_FACTOR * [get_page_width]]
	append geometry [expr int($display_width)] x [expr int($display_height)]
#	puts stdout "Displaying Image"
	if { $DISPLAY_IMAGE == $XV } {
	    set xvprocess [exec xv $filename &]
	    puts stdout "xvprocess $xvprocess"
	} else {
# use the canvas...
	DISPLAY_INTERVALS .zoning_window.work_space $ZONING_SCALE_FACTOR
	FIND_LINES
	}
    } else {
	popup_image_failure_win
    }
    puts stdout "Determining Line boundaries"

}


proc init_zoning_display { window } {
    global ZONING_SCALE_FACTOR BACKGROUND FOREGROUND scroll_inc
	wm geometry $window 800x800
	wm title $window "Zoning Window"
	wm minsize $window 400 300
        $window configure -background $BACKGROUND

 
    set canvas_width 1000
    set canvas_height 1000

   canvas $window.work_space -bg white -xscrollcommand \
	  "$window.xscroller set" -yscrollcommand \
	  "$window.yscroller set" -xscrollincrement \
	   $scroll_inc -cursor {crosshair black gray}  \
	   -width $canvas_width -height $canvas_height 
# two scrollbars
    scrollbar $window.xscroller -command "$window.work_space xview" -orient horizontal -background $BACKGROUND
    scrollbar $window.yscroller -command "$window.work_space yview" -background $BACKGROUND

    pack $window.xscroller -side bottom -fill x
}

proc max { a b } {
    if { [expr $a] > [expr $b] } {
	return $a
    } else {
	return $b
    }
}





set x_init 0
set y_init 0
set x_final 0
set y_final 0

set started_region 0
set region_count 0


proc initialize_region_grab { window } {
#
#
# facilitates the grabbing of a rectangle of the window
# using mouse button 1
# canvas subwindow must be called $window.work_space

    global x_init y_init x_final y_final started_region region_data region_list region_id arrow_in_progress current_arrow
    
    bind $window.work_space <ButtonPress-1> {
	if [expr ! $started_region] {
	    grab set $window 
	    set x_init [$window.work_space canvasx %x]
	    set y_init [$window.work_space canvasy %y]

	    set region_id [$window.work_space create rectangle $x_init $y_init $x_init $y_init -outline black -width 3 ]
	    $window.work_space itemconfigure $region_id -tags region$region_id

	    set started_region 1

	}
    }
    bind $window.work_space <ButtonRelease-1> {
	set x_final [$window.work_space canvasx %x]
	set y_final [$window.work_space canvasy %y]
	
	$window.work_space coords region$region_id $x_init $y_init $x_final $y_final


	# if finishing a rectangle, initialize its stuff in the array
	if {$x_init <= $x_final} {
	    set region_data($region_id,x_init) $x_init
	    set region_data($region_id,x_final) $x_final
	} else {
	    set region_data($region_id,x_final) $x_init
	    set region_data($region_id,x_init) $x_final
	}
	if {$y_init <= $y_final} {
	    set region_data($region_id,y_init) $y_init
	    set region_data($region_id,y_final) $y_final
	} else {
	    set region_data($region_id,y_init) $y_final
	    set region_data($region_id,y_final) $y_init
	}
	
	set region_data($region_id,next_region_id) 0
	lappend region_list $region_id
	
	make_region_buttons $region_id	    

	set started_region 0
	grab release $window
    }
    
    bind $window.work_space <B2-Motion> {
	if $arrow_in_progress {
	    set curx [$window.work_space canvasx %x] 
	    set cury [$window.work_space canvasy %y]
	    $window.work_space coords $current_arrow 0 0 $curx $cury
	}
    }
    bind $window.work_space <B1-Motion> {
	if $started_region {

	    set curx [$window.work_space canvasx %x] 
	    set cury [$window.work_space canvasy %y]

	    $window.work_space coords region$region_id $x_init $y_init $curx $cury


	} 
    }
    bind $window <Leave> {
	# on leaving the display, release control of the mouse etc.
	# maybe make it scroll instead?
	if $started_region {
	    grab release $window
	    set started_region 0
	    $window.work_space coords region$region_id 0 0 0 0  
	}
    }
}



set arrow_in_progress 0

proc make_region_buttons {reg_id } {
    global region_data kill_button_data next_button_data arrow_in_progress current_arrow

    set x_init $region_data($reg_id,x_init)
    set y_init $region_data($reg_id,y_init)

    set next_num [$window.work_space create rectangle $x_init $y_init [expr $x_init + 40] [expr $y_init + 20]  -tags "region$reg_id next_button$reg_id"]
#statement above had -fill blue between 20 and -tags
    set next_button_data($next_num,reg_id) $reg_id
    $window.work_space bind next_button$reg_id <Double-2> {
	set reg_id $next_button_data([$window.work_space find withtag current],reg_id)
	if { $arrow_in_progress } {
	    finish_arrow $reg_id
	} else {
	    set canvas_x [$window.work_space canvasx %x] 
	    set canvas_y [$window.work_space canvasy %y]
	    start_arrow $reg_id $canvas_x $canvas_y
	    puts stdout "Starting an arrow at $canvas_x $canvas_y"
	}
    }
    set kill_num [$window.work_space create rectangle [expr $x_init] $y_init [expr $x_init + 20] [expr $y_init + 20] -fill red  -tags "region$reg_id kill_button$reg_id"]
    set kill_button_data($kill_num,reg_id) $reg_id

    $window.work_space bind kill_button$reg_id <Double-2> {
	set reg_id $kill_button_data([$window.work_space find withtag current],reg_id)
	destroy_region $reg_id $window.work_space
    }
}




proc start_arrow { reg_id x_start y_start } {
    global arrow_in_progress next_button_data region_data current_arrow
    set path_name $window.work_space
# start an arrow in the middle of the little red button
    
    

    set arrow [$window.work_space create line $x_start $y_start $x_start $y_start -width 3 -arrow last -arrowshape {6.0m 8.0m 1.5m} -fill blue -tags arrow$reg_id]

    set region_data($reg_id,arrow) $arrow
    set arrow_in_progress 1
    set current_arrow $arrow
}


proc destroy_region { reg_id path_name } {
    $path_name delete region$reg_id
    puts stdout "Destroying $reg_id"
}