require 'spec_helper'

describe GeoRuby::SimpleFeatures::MultiLineString do

  def point(x, y)
    GeoRuby::SimpleFeatures::Point.from_x_y x,y
  end
  def line(*xy)
    GeoRuby::SimpleFeatures::LineString.from_coordinates [*xy]
  end
  def lines(*lines)
    GeoRuby::SimpleFeatures::MultiLineString.from_line_strings lines
  end

  it "should create a valid ewkb" do
    GeoRuby::SimpleFeatures::Geometry.from_ewkb(lines(line([0,0],[4,0]),line([0,2],[4,2])).as_ewkb)
  end

  describe "locate_point" do
    
    context "examples" do

      it "should find 2,1 at 0.5 between 0,0 and 4,0" do
        lines(line([0,0],[4,0])).locate_point(point(2,1)).should == 0.5
      end

      it "should find 2,1 at 1.5 for (0,4)...(0,1) and (0,0)...(4,0)" do
        lines(line([0,4],[0,1]), line([0,0],[4,0])).locate_point(point(2,1)).should == 1.5
      end
    
    end

  end

  describe "interpolate_point" do
    
    context "examples" do

      it "should find 0.5 at (2,0) between 0,0 and 4,0" do
        lines(line([0,0],[4,0])).interpolate_point(0.5).should == point(2,0)
      end

      it "should find 1.5 at (2,0) for (0,4)...(0,1) and (0,0)...(4,0)" do
        lines(line([0,4],[0,1]), line([0,0],[4,0])).interpolate_point(1.5).should == point(2,0)
      end
      
    end

  end

end

describe GeoRuby::SimpleFeatures::LineString do

  def point(x, y)
    GeoRuby::SimpleFeatures::Point.from_x_y x,y
  end
  def line(*xy)
    GeoRuby::SimpleFeatures::LineString.from_coordinates [*xy]
  end

  describe "locate_point" do
    
    context "examples" do

      it "should find 2,1 at 0.5 between 0,0 and 4,0" do
        line([0,0],[4,0]).locate_point(point(2,1)).should == 0.5
      end

      it "should find 2,1 at 0.5 between 0,0 and 4,0 (with several segments)" do
        line([0,0],[2,0],[4,0]).locate_point(point(2,1)).should == 0.5
      end
      
    end

  end


end

describe GeoRuby::SimpleFeatures::LineString::PointLocator do

  def point(x, y)
    GeoRuby::SimpleFeatures::Point.from_x_y x,y
  end
  alias_method :p, :point

  def locator(target, departure, arrival)
    GeoRuby::SimpleFeatures::LineString::PointLocator.new target, departure, arrival
  end
  
  context "examples" do

    it "should locate 0,y at 0 between 0,0 and 4,0" do
      -10.upto(10) do |y|
        locator(p(0,y), p(0,0), p(4,0)).locate_point.should be_zero
      end
    end

    it "should locate 2,y at 0.5 between 0,0 and 4,0" do
      -10.upto(10) do |y|
        locator(p(2,y), p(0,0), p(4,0)).locate_point.should == 0.5
      end
    end

    it "should locate 4,y at 1 between 0,0 and 4,0" do
      -10.upto(10) do |y|
        locator(p(4,y), p(0,0), p(4,0)).locate_point.should == 1
      end
    end

    it "should find 2,y at a distance of y from 0,0 and 4,0" do
      -10.upto(10) do |y|
        locator(p(2,y), p(0,0), p(4,0)).distance_from_segment.should be_within(0.001).of(y.abs)
      end
    end

  end

end