"""The curvepulator, for generating manipulable & animatable curves. 

Version 0.1

Features:
	* creates new curves based on the shape of an existing one
	  with random variation
	* ability to adjust the amount of created curves
	  - also after restarts (they are gotten from scene based on parenting)
	* adding tapering (& modifying) curves to the generated ones
	  - poweful for animation
	  - only works with current cvs

Todo:
	- use the geometry of the target object to guide positioning
	- animation features
	
Bugs:
	- the randomly variated bez. handles are not in
	  possible positions for the aligned mode they are in
	
To think:
	- merge with beast?
	 * add curve support
	 * modifications to generated things
"""

from __future__ import division

import Blender
from Blender import Curve, Object, Scene, BezTriple
from Blender import Noise
from Blender.Mathutils import Vector
from Blender import Registry #only for getting previous guiding curve for default

import ScriptUI
em = ScriptUI.EventManager()

AMOUNT = 5
BEVRESOL = 10
W = 0.1
DENSITY = 5

#target = Blender.Object.Get('shapetarget')
#targetmesh = NMesh.GetRawFromObject('target')
#bbox = target.getBoundBox()
#start = bbox[2] #up-left-behind .. at least in def cube
#end = bbox[4] #down-right-front

#trmat = target.getMatrix()

scene = Scene.getCurrent()
print "----------------" 


def trans(vecnum): #to be fixed
	#print "Trans: %s -> %s" % (gc[0].vec[1], start)
	return Vector(vecnum) #* trmat

def variate(f):
	return (f/2) + (f/2 * Noise.random())
	#probably different things needed in diff. places


def make_btris(gc, mod):
	btris = []
	for gp in gc:
		hnd1 = trans(gp.vec[0])
		knot = trans(gp.vec[1])
		hnd2 = trans(gp.vec[2])
		hnd1.z += variate(mod)
		knot.z += variate(mod)
		hnd2.z += variate(mod)
		btri = BezTriple.New((hnd1.x, hnd1.y, hnd1.z, 
	 	                      knot.x, knot.y, knot.z,
	  	                    hnd2.x, hnd2.y, hnd2.z))
		btris.append(btri)
	return btris


def create_curve(btris):
	ob = Object.New('Curve') #the Blender Object this wraps
	cob = Curve.New() #the Blender Curve object
	
	bez = cob.appendNurb(btris[0]) 
	for btri in btris[1:]:
		bez.append(btri)
	cob.setExt2(variate(W))
	cob.setBevresol(BEVRESOL)
	
	ob.link(cob)
	return ob

def same(a, b):
	"""Normal Python identity comparison does not work in bpython.
	
	This little function implements it 'the Blender way', for now."""
	if not None in (a,b):
		try:
			return (a.getType() == b.getType()) and (a.name == b.name)
		except AttributeError:
			raise ValueError, "Non-Blender objects in BObject comparison"
	else:
		return False #means None != None. how bad is that?

class Curvefill:
	def __init__(self, guide=None):
		self.curves = [] #the Blender objects wrapped
		self.guide = guide
		self.assign_guide(guide)
		self.update_curves()
	
	def update_curves(self):
		def owned(ob):
			if self.guide is not None:
				return same(ob.parent, self.guide)
			else:
				return False 		
		self.curves = [c for c in scene.getChildren()
		               if owned(c)]
		self.curves.reverse() 
		
	def assign_guide(self, guide=None):
		if guide is None: #the GUI calls like this
			try:
				self.guide = Blender.Object.GetSelected()[0]
			except IndexError:
				pass
		if self.guide is not None:
			self.gc = self.guide.getData()[0] #cur'nurb'
			self.update_curves()
		print "guide:", self.guide
		
	def _add(self):
		#print 'adding'
		mod = self.amount / DENSITY
		btris1 = make_btris(self.gc, mod)
		btris2 = make_btris(self.gc, -mod)
		ob1 = create_curve(btris1)
		ob2 = create_curve(btris2)
		self.curves.append(ob1)
		self.curves.append(ob2)
		scene.link(ob1)
		scene.link(ob2)
		self.guide.makeParent([ob1, ob2]) #could be given 'fast' option
		
	def _remove(self):
		#print 'removing'
		c = self.curves.pop()
		scene.unlink(c)
		c = self.curves.pop()
		scene.unlink(c)
				
	def set_amount(self, num):
		#self.update_curves() #something/-one may have changed them
		changed = False
		while num > self.amount:
			self._add()
			if not changed:
				changed = True
		while num < self.amount:
			self._remove()
			if not changed:
				changed = True
		return changed
	def get_amount(self):
		return len(self.curves)
	amount = property(get_amount, set_amount)
				
	def __str__(self):
		return 'curvatures purvatures', str(self.curves)

d = Blender.Registry.GetKey('machina', True)
if d:
	try:
		guide = d['prevguide']
	except:
		print "could not get data"
		print d
		guide = None
	else:
		print "got:", guide
else:
	print "first run, right?"
	d = {}
	guide = None
	
c = Curvefill(guide)

def quit():
	print "O"
	d['prevguide'] = c.guide #to get in next run
	Blender.Registry.SetKey('machina', d, True)
	print "saved:", d
	em.exit()
	
exitbtn = em.PushButton("Exit", x=300, bevent=quit)
assignbtn = em.PushButton("Assign guiding curve", bevent=c.assign_guide)
			
def slideamount():
	try:
		if c.set_amount(amountsld.value):
			Blender.Redraw()
	except AttributeError:
		print "."
		pass
	
amount = c.amount or AMOUNT
amountsld = em.Slider("amount", initvalue=amount, x=100,
    								   max=20,
				    					 bevent=slideamount)

#taperer = Object.Get('taperer')
#c.taperob = taperer #c.setTaperOb(taperer)
#print "taperer", c.taperob

em.run()