#!/usr/bin/ruby
# WA5ZNU

$FONTSIZE=12

$axesTextColor = "stroke:blue;"
$textStyle="text-anchor: center; Font-Family: Fixed; font-size: %spt; " % ($FONTSIZE)
$myStyle = "fill:none; stroke:red; stroke-width: 0.5;"
$dotStyles = ["fill:blue;", "fill:green;", "fill:red;"]
$strokeStyles = ["stroke:blue;", "stroke:green;", "stroke:red;"]
$polyLineStyles = ["fill:none; stroke:blue;", "fill:none; stroke:green;", "fill:none; stroke:red;"]
$viewBox = 'viewBox="0 0 800 800"'

# svg offers scaling as well, but at least until 1.2 it seems not possible to scale views without
# scaling fonts.

def rect(rho, theta)
  theta = theta - 90 # convert to north=0=up
  theta = Math::PI * theta / 180.0
  return [rho * Math::cos(theta), rho * Math::sin(theta)]
end


class Text
  def initialize(data, x, y,scale)
    @SCALE=scale
    @style = nil
    @x = x*@SCALE
    @y = y*@SCALE
    @data = data
  end
  def set_style(style)
    @style = style
  end
  def getXML()
    buf = "<text "
    if @style != nil:
      buf += " style='"+@style+"' "
    end
    buf += "x='"+(@x).to_s+"' "
    buf += "y='"+(@y).to_s+"'>"
    buf += @data
    buf += "</text>"
    return buf
  end
end

class Circle
  def initialize(cx, cy, r, scale)
    @SCALE=scale
    @style = nil
    @cx = cx*@SCALE
    @cy = cy*@SCALE
    @r = r*@SCALE
  end
  def set_style(style)
    @style = style
  end
  def getXML()
    buf = "<circle"
    if @style != nil:
        buf += " style='"+@style+"' "
    end
    buf += "cx='"+(@cx).to_s+"' "
    buf += "cy='"+(@cy).to_s+"' "
    buf += "r='"+(@r).to_s+"' />"
    return buf
  end
end

class Line
  def initialize(x1, y1, x2, y2,scale)
    @SCALE=scale
    @style = nil
    @x1 = x1*@SCALE
    @x2 = x2*@SCALE
    @y1 = y1*@SCALE
    @y2 = y2*@SCALE
  end
  def set_style(style)
    @style = style
  end
  def getXML()
    buf = "<line"
    if @style != nil:
        buf += " style='"+@style+"' "
    end
    buf += "x1='"+(@x1).to_s+"' "
    buf += "y1='"+(@y1).to_s+"' "
    buf += "x2='"+(@x2).to_s+"' "
    buf += "y2='"+(@y2).to_s+"' />"
    return buf
  end
end

class Polyline
  def initialize(points)
    @style = nil
    @points = points
  end
  def set_style(style)
    @style = style
  end
  def getXML()
    buf = "<polyline"
    if @style != nil:
      buf += " style='"+@style+"' "
    end
    buf += "points='"+@points+"' />"
    return buf
  end
end

class LIT
  def initialize(text)
    @buf = text
  end
  def getXML()
    return @buf
  end
end

class TRANSFORM_BEGIN < LIT
  def initialize(x, y)
    super("<g transform='translate(#{x}, #{y})'>")
  end
end

class TRANSFORM_END < LIT
  def initialize()
    super('</g>')
  end
end
  

class SVG
  def initialize(x,y,scale)
    @SCALE=scale
    @buf = [LIT.new('<?xml version="1.0"?>'),
            LIT.new('<svg ' + $viewBox + ' xmlns="http://www.w3.org/2000/svg" version="1.1">'),
            TRANSFORM_BEGIN.new(x*@SCALE, y*@SCALE)]
  end
  def addElement(element)
    @buf << element
  end
  def getXML()
    @buf << TRANSFORM_END.new()
    buf2 = @buf.collect{ |x| x.getXML() }
    buf2 << '</svg>'
    return buf2.join("\n")
  end
end

class Patterns
  def initialize(max_db, min_db, db_graph_spacing,scale)
    @POLAR_LABEL_STEP=15
    @MAX_DB=max_db
    @MIN_DB=min_db
    @DB_GRAPH_SPACING=db_graph_spacing
    @GRAPH_DB_RANGE=(@MAX_DB-@MIN_DB)
    @X=(@GRAPH_DB_RANGE+2*@DB_GRAPH_SPACING)
    @Y=(@GRAPH_DB_RANGE+2*@DB_GRAPH_SPACING)
    @SCALE=scale
  end

  def polarLinesGraph(filenames)
    s = SVG.new(@X,@Y,@SCALE)
    plotGraphPaper(s)
    i = 0
    for filename in filenames do 
      plotLines(i, filename, s, $polyLineStyles[i])
      i += 1
    end
    return s.getXML()
  end

  def polarDotsGraph(filenames)
    s = SVG.new(@X,@Y,@SCALE) 
    plotGraphPaper(s)
    i = 0
    for filename in filenames do 
      plotDots(i, filename, s, $dotStyles[i])
      i += 1
    end
    return s.getXML()
  end

  def mytext(str,x,y,textColorStyle)
    t2 = Text.new(str,x,y,@SCALE)
    t2.set_style($textStyle + textColorStyle)
    return t2
  end

  def plotGraphPaper(s)
    drawCircles(s)
    drawLines(s)
    plotPolarLabels(s)
  end

  def plotPolarLabels(s)
    (0.step(359,@POLAR_LABEL_STEP)).each() do |theta|
      (x,y) = rect(@GRAPH_DB_RANGE+@DB_GRAPH_SPACING, theta)
      s.addElement(mytext(theta.to_s, x, y, $axesTextColor))
      (x,y) = rect(@GRAPH_DB_RANGE, theta)
      s.addElement(plin(x, y))
    end
  end

  def drawCircles(s)
    (0.upto(@GRAPH_DB_RANGE/@DB_GRAPH_SPACING)).each() do |x|
      v=x*@DB_GRAPH_SPACING
      label = (@MIN_DB+v).to_s
      s.addElement(circ(v))
      s.addElement(mytext(label, (v), 0, $axesTextColor))
      s.addElement(mytext(label, (-v), 0, $axesTextColor))
#      s.addElement(mytext(l, 0, (v)))
#      s.addElement(mytext(l, 0, (-v)))
    end
  end

  def drawLines(s)
    s.addElement(hlin(-@GRAPH_DB_RANGE, @GRAPH_DB_RANGE, 0))
    s.addElement(vlin(0, -@GRAPH_DB_RANGE, @GRAPH_DB_RANGE))
  end

  def circ(w)
    t2 = Circle.new(0, 0, w,@SCALE)
    t2.set_style($myStyle)
    return t2
  end

  def dot(x,y,dotStyle)
    t2 = Circle.new(x, y, 0.2,@SCALE)
    t2.set_style(dotStyle)
    return t2
  end

  def plin(x, y)
    t2 = Line.new(0, 0, x, y, @SCALE)
    t2.set_style($myStyle)
    return t2
  end

  def hlin(x1, x2, y)
    t2 = Line.new(x1, y, x2, y,@SCALE)
    t2.set_style($myStyle)
    return t2
  end

  def vlin(x, y1, y2)
    t2 = Line.new(x, y1, x, y2,@SCALE)
    t2.set_style($myStyle)
    return t2
  end

  def plotLines(i, filename, s, polyLineStyle)
    s.addElement(mytext(filename, 0, @Y + i * $FONTSIZE*2/@SCALE, $textStyle + $strokeStyles[i]))
    points = ""
    for line in open(filename)
      (theta,rho) = line.split()
      nrho = Float(rho)-@MIN_DB
      ntheta = Float(theta)
      (x,y) = rect(nrho, ntheta)
      points = points + ((x*@SCALE)).to_s + "," + ((y*@SCALE)).to_s+","
      #s.addElement(mytext(rho, x, y))
    end
    t2 = Polyline.new(points)
    t2.set_style(polyLineStyle)
    s.addElement(t2)
  end

  def plotDots(i, filename, s, dotStyle)
    s.addElement(mytext(filename, 0, @Y + i * $FONTSIZE*2/@SCALE, $textStyle + $strokeStyles[i]))
    for line in open(filename)
      (theta,rho) = line.split()
      nrho = Float(rho)-@MIN_DB
      ntheta = Float(theta)
      (x,y) = rect(nrho, ntheta)
      s.addElement(dot(x,y,dotStyle))
      #s.addElement(mytext(rho, x, y))
    end
  end

end