#! python
# -*- coding: utf-8 -*-
# (c) 2011 Adrian Przekwas LGPL

from __future__ import division # allows floating point division from integers
import FreeCAD, Part
from FreeCAD import Base

class MySpring:
   def __init__(self, obj):
      ''' Add the properties: Pitch, Diameter, Height, BarDiameter '''
      obj.addProperty("App::PropertyLength", "Pitch", "MySpring", "Pitch of the helix").Pitch = 5.0
      obj.addProperty("App::PropertyLength", "Diameter", "MySpring", "Diameter of the helix").Diameter = 6.0
      obj.addProperty("App::PropertyLength", "Height", "MySpring", "Height of the helix").Height = 30.0
      obj.addProperty("App::PropertyLength", "BarDiameter", "MySpring", "Diameter of the bar").BarDiameter = 3.0
      obj.Proxy = self

   def onChanged(self, fp, prop):
      if prop == "Pitch" or prop == "Diameter" or prop == "Height" or prop == "BarDiameter":
         self.execute(fp)

   def execute(self, fp):
      pitch = fp.Pitch
      radius = fp.Diameter/2
      height = fp.Height
      barradius = fp.BarDiameter/2
      myhelix = Part.makeHelix(pitch, height, radius)
      g = myhelix.Edges[0].Curve
      c = Part.Circle()
      c.Center = g.value(0)  # start point of the helix
      c.Axis = (0, 1, 0)
      c.Radius = barradius
      p = c.toShape()
      section = Part.Wire([p])
      makeSolid = True
      isFrenet = True
      myspring = Part.Wire(myhelix).makePipeShell([section], makeSolid, isFrenet)
      fp.Shape = myspring

def makeMySpring():
   doc = FreeCAD.activeDocument()
   if doc is None:
      doc = FreeCAD.newDocument()
   spring = doc.addObject("Part::FeaturePython", "My_Spring")
   spring.Label = "My Spring"
   MySpring(spring)
   spring.ViewObject.Proxy = 0
   doc.recompute()


if __name__ == "__main__":
   makeMySpring()