from OpenGL.GL import *

class Light:
	nextLightNum = 0

	def __init__(self):
		if Light.nextLightNum < GL_MAX_LIGHTS:
			self.lightNumber = GL_LIGHT0 + Light.nextLightNum
			Light.nextLightNum += 1
		else:
			print "Warning: Maximum number of lights (", GL_MAX_LIGHTS, ") exceeded"
			self.lightNumber = GL_LIGHT0 + GL_MAX_LIGHTS - 1
		self.ambient = [0, 0, 0, 1]
		self.diffuse = [1, 1, 1, 1]
		self.specular = [1, 1, 1, 1]
		self.position = [0, 0, 1, 0]
		self.attenuation = [1, 0, 0]
		self.spotDirection = [0, 0, -1]
		self.spotCutoff = 180
		self.spotExponent = 0

	def apply(self):
		glEnable(self.lightNumber)
		glLightfv(self.lightNumber, GL_POSITION, self.position)
		glLightfv(self.lightNumber, GL_AMBIENT, self.ambient)
		glLightfv(self.lightNumber, GL_DIFFUSE, self.diffuse)
		glLightfv(self.lightNumber, GL_SPECULAR, self.specular)
		glLightf(self.lightNumber, GL_CONSTANT_ATTENUATION, self.attenuation[0])
		glLightf(self.lightNumber, GL_LINEAR_ATTENUATION, self.attenuation[1])
		glLightf(self.lightNumber, GL_QUADRATIC_ATTENUATION, self.attenuation[2])
		glLightf(self.lightNumber, GL_SPOT_CUTOFF, self.spotCutoff)
		if self.spotCutoff < 180:
		    glLightfv(self.lightNumber, GL_SPOT_DIRECTION, self.spotDirection.vec)
		    glLightf(self.lightNumber, GL_SPOT_EXPONENT, self.spotExponent)

	def enable(self):
		glEnable(self.lightNumber)

	def disable(self):
		glDisable(self.lightNumber)