package require tkpath
namespace eval ::ix {
    proc rc {} {return [format "\#%06x" [expr "int(floor(rand() * 16))"]]}
    proc mat_note {p t item} {
	variable _
	set id [lindex [$p.m itemcget $item -tags] 1]
	set len [expr [dict get $_($t) $id xx] - [dict get $_($t) $id x]]
	set vel [$p.m itemcget $item -fillopacity]
	pd [concat $t.rp _cb note [dict get $_($t) $id y] $vel $len \;]}

    proc mat_click {m button action p t x y} {
	variable _
	switch $m {
	    control {mat_draw $action $p $t $x $y}	    
	    "" {
		set clicked [$p.m find overlapping $x $y $x $y]
		switch $action {
		    hover {
			foreach item $clicked {
			    if {[lindex [$p.m itemcget $item -tags] 0] eq "item"} {
				mat_note $p $t $item
			    }
			}
		    }
		    first {
			#		if {$clicked ne ""} {
			set _($t:cl) $clicked
			#		}
			foreach xy {x y}  {set _($t:f$xy) [set $xy]}
		    }
		    motion {
			set mx [expr $x - $_($t:cx)]
			set my [expr $y - $_($t:cy)]
			foreach xy {x y} {
			    set mvt [mat_tr $p $t $xy d [expr $$xy - $_($t:c$xy)]]
			    switch $button {
				1 {
				    foreach ab {a b} {
					set _($t:${xy}$ab) [expr $_($t:${xy}$ab) - $mvt]   
				    }
				}
				2 {
				    set _($t:${xy}a) [expr $_($t:${xy}a) - $mvt]
				    set _($t:${xy}b) [expr $_($t:${xy}b) + $mvt]
				}
			    }
			}
			switch $button {
			    1 {			    
				if {$clicked ne ""} {
				    set items $clicked
				} else {
				    set items [$p.m find withtag item] 			   
				    mat_gridlines $p $t
				}
				foreach item $items {
				    set m [$p.m itemcget $item -matrix]
				    set m [list [lindex $m 0] [lindex $m 1] [list [expr [lindex [lindex $m 2] 0] + $mx] [expr [lindex [lindex $m 2] 1] + $my]]]
				    $p.m itemconfigure $item -matrix $m
				}
			    }
			    2 {
				foreach item [$p.m find withtag item] {
				    set id [lindex [$p.m itemcget $item -tags] 1]
				    set px [mat_tr $p $t x t [dict get $_($t) $id x]]
				    set py [mat_tr $p $t y t [dict get $_($t) $id y]]
				    set sx [mat_tr $p $t x id [expr [dict get $_($t) $id xx] - [dict get $_($t) $id x]]]
				    set sy [mat_tr $p $t y id 1]
				    $p.m coords $item [::tkpath::coords rect $px $py $sx $sy -rx 3 -ry 3]
				}
				mat_gridlines $p $t
			    }
			    3 {
				set velo [expr ($x - $_($t:cx)) / 100.0]
				foreach item $_($t:cl) {
				    set vel [expr $velo + [$p.m itemcget $item -fillopacity]]
				    if {$vel > 1} {set vel 1}
				    if {$vel < 0} {set vel 0}
				    $p.m itemconfigure $item -fillopacity $vel
				}
			    }
			}			
		    }
		}
		foreach xy {x y}  {set _($t:c$xy) [set $xy]}
	    }
	}
    }
    
    proc mat_draw {action p t x y} {
	variable _
	switch $action {
	    motion {
		if {$x >= $_($t:cx)} {set xa $_($t:cx);set xb $x} else {set xa $x;set xb $_($t:cx)}
		$p.m coords drawing [::tkpath::coords rect $xa $y [expr $xb - $xa] [mat_tr $p $t y id 1] -rx 3 -ry 3]
		set yi [mat_tr $p $t y i $y]
		dict set _($t) $_($t:i) x [mat_tr $p $t x i $xa]
		dict set _($t) $_($t:i) y $yi
		dict set _($t) $_($t:i) xx [mat_tr $p $t x i $xb]
		dict set _($t) $_($t:i) yy $yi
		pd [concat $t.rp _cb note $yi 0.8 \;]}
	    first {
		foreach xy {x y}  {set _($t:c$xy) [set $xy]}
		$p.m create path [::tkpath::coords rect $_($t:cx) $_($t:cy) 0 0 -rx 3 -ry 3] -tags drawing -fill green -fillopacity 0.8}
	    release {
		$p.m itemconfigure drawing -tags [list item $_($t:i)] -matrix {{1.0 0.0} {0.0 1.0} {0.0 0.0}}
		incr _($t:i) 2}}}

    proc mat_tr {p t d inv v} {
	variable _
	array set dm {x width y height}
	switch $inv {
	    t {return [expr ($v - $_($t:${d}a)) / ($_($t:${d}b) - $_($t:${d}a) + 0.0) * [winfo $dm($d) $p.m]]}
	    i {return [expr ($_($t:${d}b) - $_($t:${d}a)) * $v /([winfo $dm($d) $p.m] + 0.0) + $_($t:${d}a)]}
	    d {return [expr ($_($t:${d}b) - $_($t:${d}a)) * $v /([winfo $dm($d) $p.m] + 0.0)]}
	    #	    id {return [expr $v / ($_($t:${d}b) - $_($t:${d}a) + 0.0) * [winfo $dm($d) $p.m]]}
	    id {return [expr abs($v / ($_($t:${d}b) - $_($t:${d}a) + 0.0) * [winfo $dm($d) $p.m])]}}}

    proc mat_zoomReset {p t} {
	variable _
	set _($t:ya) $_($t:yao);set _($t:yb) $_($t:ybo);set _($t:xa) $_($t:xao);set _($t:xb) $_($t:xbo)
	mat_gridlines $p $t}

    proc mat_new {path target w h bg ln xa xb ya yb qx qy} {
	variable _
	set i 0
	foreach xy {x y} {foreach ab {a b} {set ${xy}${ab}o [set ${xy}${ab}]}}
	foreach a {i ln xa xb ya yb xao xbo yao ybo qx qy} {set _($target:$a) [set $a]}
	if {[winfo exists $path.m] != 1} {
	    canvas $path.m -bg $bg -width $w -height $h
	    pack $path.m -side left
	    bind $path.m <Motion> "::ix::mat_click {} 0 hover $path $target %x %y"
	    foreach m {"Control-" "" "Shift-"} {
		foreach bn {1 2 3} {
		    set b [list [concat $bn first] [concat B${bn}-Motion motion] [concat ButtonRelease-$bn release]]
		    foreach ba {0 1 2} {
			bind $path.m <$m[lindex [lindex $b $ba] 0]> "::ix::mat_click [list [string tolower [string trimright $m -1]]] $bn [lindex [lindex $b $ba] 1] $path $target %x %y"}}}
	    set bd [expr {[$path cget -bd] * 2}]
            $path configure -bg gray -width [expr [winfo width $path.m] + $bd] -height [expr [winfo height $path.m] + $bd]
	    mat_gridlines $path $target}}
    
    proc mat_gridlines {path target} {
	variable _
#	puts gridlines
	set w $path.m
	$w delete gridlines
	set gh [winfo height $w]
	set gw [winfo width $w]
	foreach item [$w find withtag gridline] {$w delete $item}
	foreach xy {x y} {
	    array set ta {x n y w}
	    array set tj {x center y left}
	    array set igx {y width x height}
	    if {$_($target:${xy}a) > $_($target:${xy}b)} {set oa ">=";set ob "-"} {set oa "<=";set ob "+"}
	    for {set x [expr int($_($target:${xy}a) / ($_($target:q${xy}) + 0.0) + 1)*($_($target:q${xy}) + 0.0)]} {[expr $x $oa $_($target:${xy}b)]} {set x [expr $x $ob $_($target:q${xy})]} {
		set og [mat_tr $path $target $xy t $x]
		set invgeo [winfo $igx($xy) $w]
		switch $xy {y {set coords [concat M 0 $og L $invgeo $og]}
		    x {set coords [concat M $og 0 L $og $invgeo]}}
		$w lower [$w create path $coords -stroke $_($target:ln) -strokedasharray 2 -tags gridline -strokewidth 1]
		$w lower [$w create text [lrange $coords 1 2] -font {{Bitstream Vera Sans} 8} \
			      -fill green -anchor $ta($xy) -text $x -justify $tj($xy) -tags gridline]}}}}

#> mat frame
#. -bd 3 #w 384 #h 144 #bg white #ln purple
#. #Xa 123 #Xb 2000 #Ya 0 #Yb 127 #qx 125 #qy 1
#. @list  ::ix::mat_add .- .| {.#1} .#2 .#3 .#4
#. @add  ::ix::mat_add .- .| {.#1} .#2 .#3 .#4
puts "mat .- .|"
::ix::mat_new .- .| .#w .#h .#bg .#ln .#Xa .#Xb .#Ya .#Yb .#qx .#qy