require 'rexml/document'
require 'time'
require 'osx/cocoa'
# require 'rubygems'
# require 'units'

# great resources about distance calculations on web
# http://williams.best.vwh.net/avform.htm
# http://www.movable-type.co.uk/scripts/latlong.html
# http://www.movable-type.co.uk/scripts/latlong-vincenty.html
# http://ajax.suaccess.org/rubyisms-in-rails/converting-between-degrees-and-radians/

include Math
include REXML

SUMMARY_KO = { :dist=>"전체 거리 : %.2f Km", :time=>"시간 : %d분 %d초", :max_v=>"최고 속도 : %.2f Km/시", :avg_v=>"평균 속도 : %.2f Km/시" }
SUMMARY_EN = { :dist=>"Total Distance : %.2f Km", :time=>"Time : %d:%d", :max_v=>"Max Velocity : %.2f Km/hr", :avg_v=>"Avg Velocity : %.2f Km/hr" }
SUMMARY = SUMMARY_KO

class Numeric
  def to_rad
    self*Math::PI/180
  end
  # add_unit_conversions(:angle => { :radians => 1, :degrees => Math::PI/180 })
  # add_unit_aliases(:angle => { :degrees => [:degree], :radians => [:radian] })
end

def distVincenty(lat1, lon1, lat2, lon2) 
  a, b = 6378137.0, 6356752.3142
  f = 1/298.257223563;                              # WGS-84 ellipsiod
  l = (lon2-lon1).to_rad
  u1 = atan((1-f) * tan(lat1.to_rad))
  u2 = atan((1-f) * tan(lat2.to_rad))
  sinU1, cosU1 = sin(u1), cos(u1)
  sinU2, cosU2 = sin(u2), cos(u2)
  
  lambda, lambdaP = l, 2*Math::PI
  iterLimit = 19
  while ((lambda-lambdaP).abs > 1e-12 and iterLimit>0) do
    sinLambda, cosLambda = sin(lambda), cos(lambda)
    sinSigma = sqrt((cosU2*sinLambda) ** 2 + (cosU1*sinU2-sinU1*cosU2*cosLambda) ** 2)
    return 0 if (sinSigma==0)                       # co-incident points
    cosSigma = sinU1*sinU2 + cosU1*cosU2*cosLambda
    sigma = atan2(sinSigma, cosSigma)
    sinAlpha = cosU1 * cosU2 * sinLambda / sinSigma
    cosSqAlpha = 1 - sinAlpha ** 2
    cos2SigmaM = cosSigma - 2*sinU1*sinU2/cosSqAlpha
    # if (isNaN(cos2SigmaM)) cos2SigmaM = 0          # equatorial line: cosSqAlpha=0 (§6)
    c = f/16*cosSqAlpha*(4+f*(4-3*cosSqAlpha))
    lambdaP = lambda
    lambda = l + (1-c) * f * sinAlpha * \
      (sigma + c*sinSigma*(cos2SigmaM+c*cosSigma*(-1+2*cos2SigmaM*cos2SigmaM)))
    iterLimit -= 1
  end

  return nil if (iterLimit==0)                      # formula failed to converge

  uSq = cosSqAlpha * (a*a - b*b) / (b*b)
  biga = 1 + uSq/16384*(4096+uSq*(-768+uSq*(320-175*uSq)))
  bigb = uSq/1024 * (256+uSq*(-128+uSq*(74-47*uSq)))
  deltaSigma = bigb*sinSigma*(cos2SigmaM+bigb/4*(cosSigma*(-1+2*cos2SigmaM*cos2SigmaM) - \
    bigb/6*cos2SigmaM*(-3+4*sinSigma*sinSigma)*(-3+4*cos2SigmaM*cos2SigmaM)))
  b*biga*(sigma-deltaSigma)
end

def distHaversine(lat1, lon1, lat2, lon2)
  # R = 6371
  dLat = (lat2-lat1).to_rad
  dLon = (lon2-lon1).to_rad
  a = sin(dLat/2) * sin(dLat/2) + cos(lat1.to_rad) * cos(lat2.to_rad) * sin(dLon/2)**2
  c = 2 * atan2(sqrt(a), sqrt(1-a)) 
  6371 * c * 1000;
end

def velocity(dist, t_int)
  (dist / 1000) / t_int * 3600
end

def gps_calc(doc, path, loc_f, h_f, t_f, cut_interval = 60 * 5)
  result = []
  rhash = { :data => [] }
  
  pre_lat, pre_lon, pre_h, pre_t = 0, 0, 0, 0
  start_time, total_dist, total_points, time_int, max_v = nil, 0, 0, 0, 0

  doc.elements.each(path) do |p|
    lat, lon = loc_f.call(p)
    h = h_f.call(p)
    t = t_f.call(p)
    
    start_time = t if start_time.nil?
    
    if pre_lat != 0 then
      time_int = t - pre_t
      if time_int <= cut_interval then
        dist = distHaversine(lat, lon, pre_lat, pre_lon)
        total_dist += dist
        total_points += 1
        v = velocity(dist, time_int)
        max_v = v if v > max_v
        rhash[:data] << [t - start_time, dist, v]
      end
    end

    if time_int > cut_interval then
      avg_v = velocity(total_dist, pre_t - start_time)
      rhash[:start_time] = start_time
      rhash[:total_points]= total_points
      rhash[:total_dist] = total_dist / 1000
      rhash[:time_int] = pre_t - start_time
      rhash[:avg_v] = avg_v
      rhash[:max_v] = max_v 
      result << rhash
      rhash = { :data => [] }      
      total_dist, total_points, max_v, time_int = 0, 0, 0, 0
      pre_lat, pre_lon, start_time = 0, 0, nil
    else
      pre_lat, pre_lon, pre_h, pre_t = lat, lon, h, t
    end    
  end

  if pre_lat != 0 then
    avg_v = velocity(total_dist, pre_t - start_time)
    rhash[:start_time] = start_time
    rhash[:total_points]= total_points
    rhash[:total_dist] = total_dist / 1000
    rhash[:time_int] = pre_t - start_time
    rhash[:avg_v] = avg_v
    rhash[:max_v] = max_v 
    result << rhash
  end
  
  result    
end

def mark_x(gps_data, value, para, emphasis=false)
  position = value * para[:graph_width] / gps_data[:total_dist] + para[:margin]

  vstring = value.integer? ? value.to_s : "%.2f" % value
  label = OSX::NSString.alloc.initWithString(vstring)
  font_dict = emphasis ? para[:em_font_dict] : para[:font_dict]
  size = label.sizeWithAttributes(font_dict)
  label.drawAtPoint_withAttributes([position-size.width/2, para[:zero].y-size.height-para[:font_margin]], font_dict)
  OSX::NSRectFill([position, para[:zero].y-para[:font_margin], 1, para[:font_margin]])
end

def mark_y(gps_data, value, para, emphasis=false)
  position = value * para[:graph_height] / (gps_data[:max_v] * 1) + para[:margin]
  
  vstring = value.integer? ? value.to_s : "%.2f" % value
  label = OSX::NSString.alloc.initWithString(vstring)
  font_dict = emphasis ? para[:em_font_dict] : para[:font_dict]
  size = label.sizeWithAttributes(font_dict)
  label.drawAtPoint_withAttributes([para[:margin]-size.width-para[:font_margin], position-size.height/2], font_dict)
  OSX::NSRectFill([para[:zero].x-para[:font_margin], position, para[:font_margin], 1])
end

def make_graph(gps_data, para={})
  default = { :width=>700, :height=>500, :mark_int=>60*10, :format=>OSX::NSPNGFileType, :margin=>50, :font_size=>12, :font_margin=>3 }
  dist_scales = [[1, 2, 5, 10, 20, 50, 100], [5, 10, 20, 50, 100, 200, 1000]]
  
  default.update(para)

  canvas = OSX::NSBitmapImageRep.alloc.initWithBitmapDataPlanes_pixelsWide_pixelsHigh_bitsPerSample_samplesPerPixel_hasAlpha_isPlanar_colorSpaceName_bytesPerRow_bitsPerPixel(nil, default[:width], default[:height], 8, 4, true, false, OSX::NSDeviceRGBColorSpace, 0, 0)
  context = OSX::NSGraphicsContext.graphicsContextWithBitmapImageRep(canvas)
  OSX::NSGraphicsContext.setCurrentContext(context)

  # font
  white = OSX::NSColor.whiteColor
  white.set
  yellow = OSX::NSColor.yellowColor
  
  font = OSX::NSFont.fontWithName_size('Helvetica', default[:font_size])
  font_dict = OSX::NSMutableDictionary.alloc.init
  font_dict.setObject_forKey(font, OSX::NSFontAttributeName)
  font_dict.setObject_forKey(white, OSX::NSForegroundColorAttributeName)
  default[:font_dict] = font_dict

  em_font = OSX::NSFont.boldSystemFontOfSize(default[:font_size]+2)
  em_font_dict = OSX::NSMutableDictionary.alloc.init
  em_font_dict.setObject_forKey(em_font, OSX::NSFontAttributeName)
  em_font_dict.setObject_forKey(OSX::NSColor.yellowColor, OSX::NSForegroundColorAttributeName)
  default[:em_font_dict] = em_font_dict  
  
  # background gradient
  gradient = OSX::NSGradient.alloc.initWithStartingColor_endingColor(OSX::NSColor.blueColor, OSX::NSColor.blackColor)
  gradient.drawInRect_angle([0, 0, default[:width], default[:height]], 90)
  
  # lines   
  default[:zero] = OSX::NSMakePoint(default[:margin], default[:margin])
  default[:x_end] = OSX::NSMakePoint(default[:width]-default[:margin], default[:margin])
  default[:y_end] = OSX::NSMakePoint(default[:margin], default[:height]-default[:margin])
  path = OSX::NSBezierPath.bezierPath
  path.moveToPoint(default[:x_end])
  path.lineToPoint(default[:zero])
  path.lineToPoint(default[:y_end])
  path.stroke
  
  # labels
  # dist_label = OSX::NSString.alloc.initWithString('Km')
  # dist_size = dist_label.sizeWithAttributes(font_dict)
  # dist_label.drawAtPoint_withAttributes([default[:x_end].x+default[:font_margin], default[:x_end].y-dist_size.height-default[:font_margin]], font_dict)
  # velo_label = OSX::NSString.alloc.initWithString('Km/Hr')
  # velo_size = velo_label.sizeWithAttributes(font_dict)
  # velo_label.drawAtPoint_withAttributes([default[:y_end].x-velo_size.width-default[:font_margin], default[:y_end].y+default[:font_margin]], font_dict)

  # 
  default[:graph_width] = default[:width] - default[:margin] * 2
  default[:graph_height] = default[:height] - default[:margin] * 2
  
  # determine x scale units
  scale_index = 0
  (dist_scales[1].size-1).downto(0) { |i| scale_index=i; break if gps_data[:total_dist] > dist_scales[1][i] }
  scale = dist_scales[0][scale_index]
  
  # draw x legends
  # mark_x(gps_data, gps_data[:total_dist], default, true)
  dist = scale
  while (dist < gps_data[:total_dist]) do 
    mark_x(gps_data, dist, default)
    dist += scale
  end
  
  # mark_y(gps_data, gps_data[:max_v], default)
  velo = 10
  while (velo < gps_data[:max_v]) do
    mark_y(gps_data, velo, default)
    velo += 10
  end
  
  # draw graph
  graph = nil
  total = 0
  gps_data[:data].each do |time_int, dist, velo|
    total += dist
    point_x = (total / 1000) * default[:graph_width] / gps_data[:total_dist] + default[:margin]
    point_y = velo * default[:graph_height] / (gps_data[:max_v] * 1) + default[:margin]
    
    if graph.nil? then
      graph = OSX::NSBezierPath.bezierPath
      graph.moveToPoint(OSX::NSMakePoint(point_x, point_y))
    else
      graph.lineToPoint(OSX::NSMakePoint(point_x, point_y))
    end
    
    if (default[:mark_int] != 0) and (time_int % default[:mark_int] == 0) then
      mark_label = OSX::NSString.alloc.initWithString("%d:%02d" % [time_int / 60, time_int % 60])
      mark_size = mark_label.sizeWithAttributes(default[:font_dict])
      mark_label.drawAtPoint_withAttributes([point_x-mark_size.width/2, point_y+default[:font_margin]], default[:font_dict])
      mark = OSX::NSBezierPath.bezierPathWithOvalInRect([point_x-2, point_y-2, 4, 4])
      yellow.set
      mark.stroke
      white.set      
    end
  end
  graph.stroke
  
  # summary
  sum_y = default[:height] - default[:margin] / 2
  dist_label = OSX::NSString.alloc.initWithString(SUMMARY[:dist] % gps_data[:total_dist])
  dist_size = dist_label.sizeWithAttributes(default[:em_font_dict])
  dist_label.drawAtPoint_withAttributes([default[:width]-default[:margin]/2-dist_size.width, sum_y-dist_size.height], default[:em_font_dict])
  sum_y -= dist_size.height + default[:font_margin]
  time_label = OSX::NSString.alloc.initWithString(SUMMARY[:time] % [gps_data[:time_int]/60, gps_data[:time_int]%60])
  time_size = time_label.sizeWithAttributes(default[:em_font_dict])
  time_label.drawAtPoint_withAttributes([default[:width]-default[:margin]/2-time_size.width, sum_y-time_size.height], default[:em_font_dict])
  sum_y -= time_size.height + default[:font_margin]
  maxv_label = OSX::NSString.alloc.initWithString(SUMMARY[:max_v] % gps_data[:max_v])
  maxv_size = maxv_label.sizeWithAttributes(default[:em_font_dict])
  maxv_label.drawAtPoint_withAttributes([default[:width]-default[:margin]/2-maxv_size.width, sum_y-maxv_size.height], default[:em_font_dict])
  sum_y -= maxv_size.height + default[:font_margin]
  avgv_label = OSX::NSString.alloc.initWithString(SUMMARY[:avg_v] % gps_data[:avg_v])
  avgv_size = avgv_label.sizeWithAttributes(default[:em_font_dict])
  avgv_label.drawAtPoint_withAttributes([default[:width]-default[:margin]/2-avgv_size.width, sum_y-avgv_size.height], default[:em_font_dict])

  
  canvas.representationUsingType_properties(default[:format], nil).rubyString  
end

if ARGV.size > 0 then
  ARGV.each do |a|
    doc = Document.new(open(a))
    
    loc_f = proc { |e| e.elements['Point'].elements['coordinates'].text.split(',').collect { |s| s.to_f}[0..2] }
    h_f = proc { |e| e.elements['Point'].elements['coordinates'].text.split(',').collect { |s| s.to_f}[2] }
    t_f = proc { |e| Time.parse(e.elements['TimeStamp'].elements['when'].text).localtime }
    
    r = gps_calc(doc, 'kml/Document/Folder/Folder/Placemark', loc_f, h_f, t_f, 60*60)
    r.each do |result|
      open("graph_#{result[:start_time].strftime('%Y%m%d%H%M')}.png", 'wb') { |f| f.write(make_graph(result))} 
    end
  end
end