############################################################################
#
#	File:     trkvu.icn
#
#	Subject:  Program to display GPS track logs
#
#	Authors:  Gregg M. Townsend
#
#	Date:     April 3, 2010
#
############################################################################
#
#	This file is in the public domain.
#
############################################################################
#
#	Trkvu displays GPS track logs, using color to indicate various
#	characteristics such as velocity, direction, or time of day.
#
############################################################################
#
#	usage:  trkvu file...
#
#	Each file argument is a track log uploaded from a GPS receiver.
#	Lines that end in three decimal values specify latitude, longutude,
#	and altitude in that order.  Lines with just two values omit the
#	altitude.  Lines without data indicate breaks between segments. 
#
#	Some colorings use timestamps from the track logs.  A timestamp
#	has the form "mm/dd/yyyy hh:mm:ss" or "yyyy/mm/dd hh:mm:ss" and
#	precedes the latitude and longitude.
#
############################################################################
#
#	Track log colorings are selected by pressing a key:
#
#	F	color by File (restricting legend to files in view)
#	A	color by Age
#	O	color by Orientation (direction of travel)
#	V	color by Velocity
#	I	color by Interval duration (GPS sample rate)
#	S	color Segments in contrasting colors
#	Y	color by time of Year
#	D	color by Day of week
#	H	color by Hour of day
#	M	color by Minute (repeating colors every 10 minutes)
#	T	color by Time of day
#
#	Colorings can also be cycled:
#
#	SP or CR	cycle to next coloring
#	BS or DEL	cycle to preceding coloring
#
#	A legend explains each coloring.  If it shows individually labeled
#	color blocks, the colors encode discrete values.  If a spectrum
#	is shown, the colors vary smoothly over a continuous range.
#
#	Some colorings require timestamps.  For these, tracks lacking
#	timestamps are drawn in gray.
#
############################################################################
#
#	Zooming and Panning:
#
#	To zoom to a particular region, sweep out the region using the
#	left mouse button.  To cancel a sweep, reduce its width or height
#	to fewer than ten pixels.
#
#	The window may be resized as desired.
#
#	The following keyboard commands also affect the display region:
#
#	+ or =		zoom in
#	- or _		zoom out
#	0 or Home	zoom to initial view
#	arrow keys	pan the display  (hold Shift key for smaller pan)
#
############################################################################
#
#  Requires:  Version 9 graphics
#
############################################################################
#
#  Links:  datetime, graphics, mapnav, strings
#
############################################################################


$include "keysyms.icn"

link datetime
link graphics
link mapnav
link strings

$define BORDER 10	# border widths


record view(		# one view of data
   cs,			# cset of chars to select this view
   ltitle,		# legend title
   hproc,		# hue selection procedure
   lproc)		# legend procedure

record point(		# one point along a track
   t,			# time at point (real days & fraction since epoch)
   x, y,		# coordinates of point (longitude, latitude)
   f)			# file index


global viewlist		# list of views (view records)
global curview		# current selected view

global huelist		# list of ColorValues of 180 hues

global fnlist		# file name list (for F legend)
global fhlist		# file hue list (for F legend)

global seglist		# list of travel segments
global tmin, tmax	# earliest and latest time seen
global xmin, xmax	# westernmost and easternmost longitude seen
global ymin, ymax	# northernmost and southernmost latitude seen

global lbase		# legend baseline y value
global lclip		# clipping arguments for legend region
global mclip		# clipping arguments for map region
global stdwin		# std bg/fg window



#  ========================= Overall Control =========================

procedure main(args)
   local e, v, xywh

   Window("size=800,800", "resize=on", "canvas=hidden",
      "linewidth=2", "font=sans,bold,12", args)
   stdwin := Clone("bg=white")

   viewlist := [
      # sequence here is followed by <SP> and <BS>
      view('Ff', "File", byfile, flegend),
      view('Aa', "Age", byage, agelegend),
      view('Oo', "Orientation", orientation, olegend),
      view('Vv', "Velocity", velocity, vlegend),
      view('Ii', "Interval", byinterval, intlegend),
      view('Ss', "Segments", segments, seglegend),
      view('Yy', "time of Year", bymonth, monthlegend),
      view('Dd', "Day", byday, daylegend),
      view('Hh', "Hour", byhour, hourlegend),
      view('Mm', "Minute", byminute, minutelegend),
      view('Tt', "Time", bytime, timelegend),
      ]
   while /viewlist[-1] do pull(viewlist)

   seglist := []		# init data structures
   fnlist := []
   fhlist := []

   every load(!args)		# load data
   survey()			# find extremes
   fnlist := fnsimp(fnlist)	# simplify filename list

   WAttrib("canvas=normal")	# make display visible
   hueinit()			# init color manager
   layout()			# lay out display
   mapinit(draw, , xmin, xmax, ymax, ymin, cos(dtor((ymin + ymax) / 2)))

   if *args > 1 then
      Enqueue("f")		# show initially by file
   else if tmax > 0 then
      Enqueue("a")		# show initially by age
   else
      Enqueue("o")		# show initially by orientation

   # ==================== main event loop ====================

   while e := Event() do {
      if upto((v := \!viewlist).cs, e) then {	# if a view selector
         curview := v
         EraseArea()
         mapgen()				# regenerate map
         }
      else case e of {
         !" \n\r": nextview(+1)			# cycle view forward
         !"\b\d":  nextview(-1)			# cycle view backward
         &resize:  { layout(); mapevent(e) }	# resize window
         default:  { mapevent(e) }		# possible standard action
         }
      }
end

procedure nextview(d)			# advance to next view in sequence
   local i

   every i := 1 to *viewlist do
      if curview === viewlist[i] then {
         i := (i + *viewlist - 1 + d) % *viewlist + 1
         curview := viewlist[i]
         mapgen()
         return
         }
end



#  ========================= Input =========================

procedure load(fname)			# load data from one file
   local f, h, p, w, t, x, y, a, line, ptlist

   f := open(fname) | stop("cannot open ", fname)
   put(fnlist, fname)
   put(fhlist, huenum(*fnlist))
   while line := read(f) do {
      every put(w := [], words(line))
      if -90.0 <= numeric(w[-3]) <= 90.0 then
         a := pull(w)			# altitude
      if x := numeric(w[-1]) & y := numeric(w[-2]) then {
         t := tcrack(w[-4], w[-3]) | &null
         /ptlist := []
         put(ptlist, p := point(t, x, y, *fnlist))
         }
      else {
         put(seglist, \ptlist)
         ptlist := &null
         next
         }
      }

   put(seglist, \ptlist)
   close(f)
   if /p then
      write(&errout, "   no data: ", fname)
   return
end

procedure tcrack(date, time)		# translate date + time into real value
   local day, sec
   static smul
   initial smul := 1.0 / (24 * 60 * 60)

   if date[3] == "/" then
      date := map("CcYy/Mm/Dd", "Mm/Dd/CcYy", date)
   if date <<= "1990/01/01" then	# if indicator of missing date
      return &null
   *time =  8 | fail
   *date = 10 | fail
   day := DateToSec(date) | fail
   sec := ClockToSec(time) | fail
   return smul * (day + sec)
end

procedure survey()			# survey data ranges
   local p

   xmin := 180
   xmax := -180
   ymin := 90
   ymax := -90
   tmin := 100 * 365.25
   tmax := 0

   every p := !!seglist do {
      tmin >:= \p.t
      tmax <:= \p.t
      xmin >:= p.x
      xmax <:= p.x
      ymin >:= p.y
      ymax <:= p.y
      }

   if xmin > xmax then
      stop("   nothing to display")	# diagnostic already issued

   if tmin > tmax then
      tmin := tmax := 0

   return
end

procedure fnsimp(fnlist)		# simplify filename list
   local f, i, j, s

   if *fnlist < 2 then fail
   (coprefix ! fnlist) ? {
      i := 1
      while i := upto('/') + 1 do
         move(1)
      }
   (cosuffix ! fnlist) ? {
      tab(upto('.') | 0)
      j := -*tab(0)
      }
   f := []
   every put(f, (!fnlist)[i:j])
   return f
end



#  ========================= Color Management =========================
#
#  Map colors are taken from the fully saturated color spectrum, spaced
#  every 2 degrees in HSV space.  This yields 180 different colors, well
#  within Icon's limit of 256.  The greens are darkened a bit for better
#  contrast with the white background; but the yellows are not, because
#  a darkened yellow is really ugly.  (For better contrast, some colorings
#  use hue 55 instead of 60 for a yellow color.)

procedure hueinit()		# initialize hue table (360 entries)
   local d, d2, v

   huelist := list(360)
   every d := 0 to 359 do {
      d2 := d - d % 2			# use 2-degree quanta
      if 60 < d2 < 180 then		# darken green region
         v := integer(100 - 0.8 * (60 - abs(d2 - 120)))
      else
         v := 100
      huelist[d + 1] := HSVValue(d2 || "/100/" || v)
      }
   return
end

procedure sethue(h)		# set & cache color, given hue in degrees >= 0
   local k
   static kprev

   if h := integer(h) % 360 then
      k := huelist[h + 1]
   else				# use gray for invalid argument
      k := "gray"
   Fg(kprev ~===:= k)
   return
end

procedure huenum(n)		# return hue from ordered list
   static predef
   initial predef := [240, 0, 120, 30, 180, 300, 50, 270, 70, 210, 330]
   #                  blu red grn org cyan mgnta tan purp grn blu plum

   return predef[n] | (137 * n) % 360
end



#  ========================= Map Drawing =========================

procedure layout()			# configure window layout
   local w, h, lh

   Bg("pale weak yellow")
   Clip()
   EraseArea()
   Bg("white")

   w := WAttrib("width")
   h := WAttrib("height")

   # set legend size and baseline
   lh := 2 * BORDER + WAttrib("ascent")
   lbase := BORDER + lh - BORDER

   # set legend clipping, and clear
   lclip := [BORDER, BORDER, w - 2 * BORDER, lh]
   Clip ! ([stdwin] ||| lclip)
   Clip ! lclip
   EraseArea()

   # set map clipping, and clear
   mclip := [BORDER, lh + 2 * BORDER, w - 2 * BORDER, h - lh - 3 * BORDER]
   Clip ! mclip
   EraseArea()

   return
end

procedure draw(win, pjn, a)		# display map using curview
   local ptlist, h, n, p, q, x1, y1, x2, y2, l

   Clip ! lclip
   EraseArea()
   GotoXY(2 * BORDER, lbase)
   ltext(curview.ltitle)
   ltext(": ")
   curview.lproc(pjn)

   Clip ! mclip
   every ptlist := !seglist do {
      if *Pending() > 0 then break
      p := &null
      every q := !ptlist do {
         l := project(pjn, [q.x, q.y])
         x2 := integer(get(l))
         y2 := integer(get(l))
         x2 <:= -32767
         y2 <:= -32767
         x2 >:= 32767
         y2 >:= 32767
         if \p then {
            sethue(curview.hproc(p, q) | &null)
            DrawLine(x1, y1, x2, y2)
            }
         else if *ptlist = 1 then {
            sethue(curview.hproc(q, q) | &null)
            FillRectangle(x2 - 1, y2 - 1, 3, 3)
            }
         p := q
         x1 := x2
         y1 := y2
         }
      }
   return
end



#  ========================= Legend Writing =========================
#
#  Colors are written via &window, text in black via stdwin.

procedure ltext(s)		# write text

   return WWrites(stdwin, s)
end

procedure lhue(h, t)		# write hue block with optional caption
   local x, w

   sethue(h)
   x := WAttrib("x")
   w := WAttrib("ascent")
   FillRectangle(x, lbase + 1, w - 1, -w)
   GotoXY(x + w, lbase)
   ltext(\t)
   return
end

procedure lspectrum(h1, h2, n)	# write spectrum of 6 colors from h1 to h2
   local i, m

   /n := 6
   m := (h2 - h1) / (n - 1.0)
   every i := 1 to n do
      lhue(h1 + m * (i - 1))
   return
end



#  ========================= View Procedures =========================
#
#  View procedures are paired: a legend procedure draws the legend and a
#  hue selection procedure that chooses the hue for each segment.  (Hue
#  procedure return a value in degrees, or they fail, which draws gray.)


#  F: color segments by source file, using colors set at load time
#
#  show in the legend only those files containing a point in view
#  (note: won't show legend for tracks that "just pass through")

procedure flegend(pjn)
   local winlim, viewlim, fset, vset, i, seg, pt, x0, x1, y0, y1

   fset := set()		# set of potential file source indices
   every insert(fset, 1 to *fnlist)
   vset := set()		# set of indices of files in view

   # find limits of the current field of view
   winlim := [mclip[1], mclip[2] + mclip[4], mclip[1] + mclip[3], mclip[2]]
   viewlim := project(invp(pjn), winlim)
   x0 := get(viewlim)
   y0 := get(viewlim)
   x1 := get(viewlim)
   y1 := get(viewlim)

   # find files in view
   every seg := !seglist do {
      pt := !seg	# first pt
      if member(fset, pt.f) then {
         every pt := !seg do {
            if x0 <= pt.x <= x1 & y0 <= pt.y <= y1 then {
               delete(fset, pt.f)
               insert(vset, pt.f)
               if *fset = 0 then
                  break break
               }
            }
         }
      }

   # now, finally draw the legend
   every i := !sort(vset) do
      lhue(fhlist[i], fnlist[i] || " ")
   return
end

procedure byfile(p, q)
   return fhlist[q.f]
end


#  A: color segments by age (relative to range of timestamps seen)

procedure agelegend()

   ltext("oldest")
   lspectrum(630, 360, 12)
   ltext("newest")
   return
end

procedure byage(p, q)

   # purple oldest, green mid, red newest
   return 630. - 270. * (\q.t - tmin) / (tmax - tmin)
end


#  O: color segments by orientation (direction of travel)

procedure olegend()

   ltext("N"); lspectrum(270, 180)
   ltext("E"); lspectrum(180, 90)
   ltext("S"); lspectrum(90, 0)
   ltext("W"); lspectrum(360, 270)
   ltext("N")
   return
end

procedure orientation(p, q)

   # blue north, teal east, olive south, red west
   return 180. + rtod(atan(q.y - p.y, cos(dtor(q.y)) * (q.x - p.x)))
end


#  V: color segments by velocity

procedure vlegend()

   lhue(240, "1 ")
   lhue(210, "2 ")
   lhue(180, "3 ")
   lhue(120, "4 ")
   lhue( 55, "5 ")
   lhue( 30, "6 ")
   lhue(  0, "7 ")
   lhue(300, "8 ")
   lhue(270, "9 ")
   ltext(" mph (x1, x10, ...)")
   return
end

procedure velocity(p, q)
   local dt, dx, dy, d, mph
   static hues
   initial hues := [270, 240, 210, 180, 120, 55, 30,  0, 300, 270]
   #                  0    1    2    3    4   5   6   7    8    9
   #                      10   20   30   40  50  60  70   80   90
   #                     100  200  300  400 500 600 700  800  900

   dt := 0 < (\q.t - \p.t) | fail
   dx := cos(dtor(p.y)) * (q.x - p.x)
   dy := q.y - p.y
   d := sqrt(dx ^ 2 + dy ^ 2)
   mph := integer(2.877 * d / dt + 0.5)
   while mph > 9 do
      mph /:= 10
   return hues[mph + 1]
end


#  I: color segments by length of time interval

procedure intlegend()

   lhue(  0, "0 ")
   lhue( 30, "1 ")
   lhue( 55, "2 ")
   lhue(120, "4 ")
   lhue(180, "8 ")
   lhue(220, "16 ")
   lhue(240, "32 ")
   lhue(290, "64 sec")
   return
end

procedure byinterval(p, q)
   local dt, i
   static hues
   initial hues := [0, 30, 55, 120, 180, 220, 240, 290]
   #                 0  1   2    4    8   16   32   64

   dt := integer(86400. * (\q.t - \p.t) + 0.5) | fail
   i := (2 + integer(log(0 < dt, 2))) | 1
   return hues[i | -1]
end


#  S: emphasize individual segments in contrasting colors.

procedure seglegend()

   lspectrum(137, 12*137, 12)
   ltext("...")
   return
end

procedure segments(p, q)
   static n
   initial n := 0

   return n +:= 137
end


#  Y: color segments by time of year as a spectrum

procedure monthlegend()

   ltext("January")
   lspectrum(525, 195, 12)
   ltext("December")
   return
end

procedure bymonth(p, q)

   # cyan winter, green spring, red summer, blue fall
   return 540. - (\q.t % 365.25) * (360. / 365.25)
end


#  D: color segments by day of week

procedure daylegend()

   lhue(240, "Sun ")
   lhue(120, "Mon ")
   lhue(165, "Tue ")
   lhue( 55, "Wed ")
   lhue( 30, "Thu ")
   lhue(285, "Fri ")
   lhue(  0, "Sat ")
   return
end

procedure byday(p, q)
   static hues
   initial hues := [240, 120, 165, 55, 30, 285, 0]

   return hues[1 + ((4 + integer(\q.t)) % 7)]
end


#  H: color segments by hour in the day (0 to 11, repeated)

procedure hourlegend()

   lhue(240, "12 ")
   lhue(290, "1 ")
   lhue(350, "2 ")
   lhue( 30, "3 ")
   lhue( 80, "4 ")
   lhue(150, "5 ")
   lhue(210, "6 ")
   lhue(270, "7 ")
   lhue(330, "8 ")
   lhue( 55, "9 ")
   lhue(120, "10 ")
   lhue(180, "11 ")
   return
end

procedure byhour(p, q)
   local h
   static hues
   initial hues := [240, 290, 350, 30, 80, 150, 210, 270, 330, 55, 120, 180]

   h := integer(24 * (\q.t - integer(q.t))) | fail
   return hues[1 + h % 12]
end


#  M: color segments by minute of the hour, mod 10

procedure minutelegend()
   local i

   every i := 0 to 9 do
      lhue(huenum(i + 1), ":x" || i || " ")
   return
end

procedure byminute(p, q)
   local t

   t := 24 * 30 * (\p.t + \q.t) | fail		# time in minutes since epoch
   return huenum(1 + integer(t) % 10)
end


#  T: color segments by a time-of-day spectrum

procedure timelegend()

   ltext("midnight")
   lspectrum(600, 420, 13)
   ltext("noon")
   lspectrum(420, 240, 13)
   ltext("midnight")
   return
end

procedure bytime(p, q)

   # green morning, yellow noon, red afternoon, blue night
   return 600. - 360. * (\q.t - integer(q.t))
end