#!/usr/bin/wish

wm title . "ACPI"

set w 30
set h 115
set lv 1.0
set ld [clock seconds]
set oac DC
set started 0
set new 1

set batmax(0) 0
set batmax(1) 0

proc bat_init {} {
  global batmax

  for { set v 0} { $v < 2} { incr v } {
    set fh [open "/proc/acpi/battery/BAT$v/info"]
    while { [ gets $fh line ] >= 0 } {
      if { [ regexp {^design capacity:[ \t]*([0-9]+) mWh$} $line all max ] } {
        set batmax($v) $max
	break
      }
    }
    close $fh
  }
}

proc m_update { } {
  global .t.c w h ld lv oac started new batmax

  set ac AC
  set rate 0
  set remaining 0
  for { set v 0} { $v < 2} { incr v } {

    if { $batmax($v) == 0 } {
      continue
    }

    set fh [open "/proc/acpi/battery/BAT$v/state"]
    while { [ gets $fh line ] >= 0 } {
      if { [ regexp {^charging state:[ \t]*discharging$} $line ] } {
        set ac DC
      }
      if { [ regexp {^present rate:[ \t]*([0-9]+) mW$} $line all r ] } {
	set rate [ expr $rate + $r ]
      }
      if { [ regexp {^remaining capacity:[ \t]*([0-9]+) mWh$} $line all r ] } {
	set remaining [ expr $remaining + $r ]
      }
    }
    close $fh
  }

  set max [ expr $batmax(0) + $batmax(1) ]
  set s [ expr "$remaining.0" / $max ]
  if { $rate > 0 } {
    if {$ac == "DC"} {
      set min [ expr "int($remaining.0 / $rate * 60)" ]
    } else {
      set min [ expr "int(($max.0 - $remaining.0) / $rate * 60)" ]
    }
  } else {
    set min "???"
  }
  set unit "min"
  #echo Rem: $remaining Rate $rate Max $max Min $min


  if { $oac != $ac && $ac == "DC" } {
    tk_messageBox -icon info -title "Warning"\
    	-message "Warning: AC lost, please check" -type ok
  }
  set oac $ac
  if { $lv != $s } { 
    set now [clock seconds]
    set diff [ expr $now - $ld ]
    if { $lv < $s } {
      set f [ expr $diff * (1.0-$s) / ($s-$lv)  / 60 ]
      .t.c itemconfigure full -text [ format "%.0f" $f ]
      .t.c itemconfigure hour -text "min"
      set lv $s
      set ld $now
    } elseif { $lv && $lv > $s && $started == 1 && $diff < 1800 } {
      set f [ expr 60.0/((3600/$diff)*($lv-$s)) ]
      set f2 [ expr $f * $s ]
      .t.c itemconfigure full -text [ format "%.0f" $f ]
      .t.c itemconfigure hour -text [ format "(%.0f)" $f2 ]
    } else {
      .t.c itemconfigure full -text ""
      .t.c itemconfigure hour -text ""
    }
    set started 1
    set lv $s
    set ld $now
    set new 1
  }

  if {$new } {
    .t.c itemconfigure min  -text $min
    .t.c itemconfigure unit -text $unit
    .t.c itemconfigure ac   -text $ac

    .t.c delete battery
    .t.c create rectangle 2 [expr 2 + ((1.0-$s)*($h-0))]\
    		[expr $w+2] [expr $h+2] -fill #2b2 -outline "" -tag battery
    .t.c lower battery
    set new 0
  }

  after 30000 m_update
}

frame .t -borderwidth 0
canvas .t.c -width $w -height $h -background #eee -borderwidth 0

set rw [expr $w / 2 +2]
.t.c create text $rw 15 -tag ac
.t.c create text $rw 27 -tag full
.t.c create text $rw 39 -tag hour
.t.c create text $rw [expr $h - 8] -tag unit
.t.c create text $rw [expr $h - 20] -tag min

pack .t.c .t

bat_init
m_update