import sys
import random
import operator
import itertools

from genutil import *

random.seed(1234567)
indices = xrange(sys.maxint)

# Swizzles:
# - vector components
#   * int, float, bool vectors
#   * .xyzw, .rgba, .stpq
#   * illegal to mix
#   * not allowed for scalar types
#   * legal to chain: vec4.rgba.xyzw.stpq
#   * illegal to select more than 4 components
#
# Subscripts:
# - array-like indexing with [] operator
#   * vectors, matrices
# - read & write
# - vectors components
#   * [] accessor
# - matrix columns
#   * [] accessor
#   * note: mat4[0].x = 1.0; vs mat4[0][0] = 1.0; ??
#   * out-of-bounds accesses

#
# - vector swizzles
#   * all vector types (bvec2..4, ivec2..4, vec2..4)
#   * all precisions (lowp, mediump, highp)
#   * all component names (xyzw, rgba, stpq)
#   * broadcast each, reverse, N random
# - component-masked writes
#   * all vector types (bvec2..4, ivec2..4, vec2..4)
#   * all precisions (lowp, mediump, highp)
#   * all component names (xyzw, rgba, stpq)
#   * all possible subsets
#   * all input types (attribute, varying, uniform, tmp)
#   -> a few hundred cases
# - concatenated swizzles

#
VECTOR_TYPES	= [ "vec2", "vec3", "vec4", "ivec2", "ivec3", "ivec4", "bvec2", "bvec3", "bvec4" ]
PRECISION_TYPES	= [ "lowp", "mediump", "highp" ]
INPUT_TYPES		= [ "uniform", "varying", "attribute", "tmp" ]
SWIZZLE_NAMES	= [ "xyzw", "stpq", "rgba" ]

def getDataTypeScalarSize (dt):
	return {
		"float":	1,
		"vec2":		2,
		"vec3":		3,
		"vec4":		4,
		"int":		1,
		"ivec2":	2,
		"ivec3":	3,
		"ivec4":	4,
		"bool":		1,
		"bvec2":	2,
		"bvec3":	3,
		"bvec4":	4,
		"mat2":		4,
		"mat3":		9,
		"mat4":		16
	}[dt]

if False:
	class Combinations:
		def __init__(self, *args):
			self.lists				= list(args)
			self.numLists			= len(args)
			self.numCombinations	= reduce(operator.mul, map(len, self.lists), 1)
			print self.lists
			print self.numCombinations

		def iterate(self):
			return [tuple(map(lambda x: x[0], self.lists))]

	combinations = Combinations(INPUT_TYPES, VECTOR_TYPES, PRECISION_TYPES)
	print combinations.iterate()
	for (inputType, dataType, precision) in combinations.iterate():
		scalarSize = getDataTypeScalarSize(dataType)
		print inputType, precision, dataType

def getSwizzlesForWidth(width):
	if (width == 2):
		return [(0,), (0,0), (0,1), (1,0), (1,0,1), (0,1,0,0), (1,1,1,1)]
	elif (width == 3):
		return [(0,), (2,), (0,2), (2,2), (0,1,2), (2,1,0), (0,0,0), (2,2,2), (2,2,1), (1,0,1), (0,2,0), (0,1,1,0), (2,2,2,2)]
	elif (width == 4):
		return [(0,), (3,), (3,0), (3,2), (3,3,3), (1,1,3), (3,2,1), (0,1,2,3), (3,2,1,0), (0,0,0,0), (1,1,1,1), (3,3,3,3), (3,2,2,3), (3,3,3,1), (0,1,0,0), (2,2,3,2)]
	else:
		assert False

# Templates.

s_swizzleCaseTemplate = """
case ${{NAME}}
	values
	{
		${{VALUES}}
	}

	both ""
		precision mediump float;

		${DECLARATIONS}

		void main()
		{
			${SETUP}
			${{OP}}
			${OUTPUT}
		}
	""
end
"""[1:]

s_simpleIllegalCaseTemplate = """
case ${{NAME}}
	expect compile_fail
	values {}

	both ""
		precision mediump float;
		precision mediump int;

		${DECLARATIONS}

		void main()
		{
			${SETUP}
			${{OP}}
			${OUTPUT}
		}
	""
end
"""[1:]

class SwizzleCase(ShaderCase):
	def __init__(self, name, precision, dataType, swizzle, inputs, outputs):
		self.name		= name
		self.precision	= precision
		self.dataType	= dataType
		self.swizzle	= swizzle
		self.inputs		= inputs
		self.outputs	= outputs
		self.op			= "out0 = in0.%s;" % swizzle

	def __str__(self):
		params = {
			"NAME":		self.name,
			"VALUES":	genValues(self.inputs, self.outputs),
			"OP":		self.op
		}
		return fillTemplate(s_swizzleCaseTemplate, params)

# CASE DECLARATIONS

inFloat	= [Scalar(x) for x in [0.0, 1.0, 2.0, 3.5, -0.5, -20.125, 36.8125]]
inInt	= [Scalar(x) for x in [0, 1, 2, 5, 8, 11, -12, -66, -192, 255]]
inBool	= [Scalar(x) for x in [True, False]]

inVec4	= [Vec4(0.0, 0.5, 0.75, 0.825), Vec4(1.0, 1.25, 1.125, 1.75),
		   Vec4(-0.5, -2.25, -4.875, 9.0), Vec4(-32.0, 64.0, -51.0, 24.0),
		   Vec4(-0.75, -1.0/31.0, 1.0/19.0, 1.0/4.0)]
inVec3	= toVec3(inVec4)
inVec2	= toVec2(inVec4)
inIVec4	= toIVec4(inVec4)
inIVec3	= toIVec3(inVec4)
inIVec2	= toIVec2(inVec4)
inBVec4	= [Vec4(True, False, False, True), Vec4(False, False, False, True), Vec4(False, True, False, False), Vec4(True, True, True, True), Vec4(False, False, False, False)]
inBVec3	= toBVec3(inBVec4)
inBVec2	= toBVec2(inBVec4)

# \todo [petri] Enable large values when epsilon adapts to the values.
inMat4	= [Mat4(1.0, 0.0, 0.0, 0.0,  0.0, 1.0, 0.0, 0.0,  0.0, 0.0, 1.0, 0.0,  0.0, 0.0, 0.0, 1.0),
		   Mat4(6.5, 12.5, -0.75, 9.975,  32.0, 1.0/48.0, -8.425, -6.542,  1.0/8.0, 1.0/16.0, 1.0/32.0, 1.0/64.0,  -6.725, -0.5, -0.0125, 9.975),
		   #Mat4(128.0, 256.0, -512.0, -1024.0,  2048.0, -4096.0, 8192.0, -8192.0,  192.0, -384.0, 768.0, -1536.0,  8192.0, -8192.0, 6144.0, -6144.0)
		   ]
inMat3	= [Mat3(1.0, 0.0, 0.0,  0.0, 1.0, 0.0,  0.0, 0.0, 1.0),
		   Mat3(6.5, 12.5, -0.75,  32.0, 1.0/32.0, 1.0/64.0,  1.0/8.0, 1.0/16.0, 1.0/32.0),
		   #Mat3(-18.725, -0.5, -0.0125,  19.975, -0.25, -17.75,  9.25, 65.125, -21.425),
		   #Mat3(128.0, -4096.0, -8192.0,  192.0, 768.0, -1536.0,  8192.0, 6144.0, -6144.0)
		   ]
inMat2	= [Mat2(1.0, 0.0,  0.0, 1.0),
		   Mat2(6.5, 12.5,  -0.75, 9.975),
		   Mat2(6.5, 12.5,  -0.75, 9.975),
		   Mat2(8.0, 16.0,  -24.0, -16.0),
		   Mat2(1.0/8.0, 1.0/16.0,  1.0/32.0, 1.0/64.0),
		   Mat2(-18.725, -0.5,  -0.0125, 19.975),
		   #Mat2(128.0, -4096.0,  192.0, -1536.0),
		   #Mat2(-1536.0, 8192.0,  6144.0, -6144.0)
		   ]

INPUTS = {
	"float":	inFloat,
	"vec2":		inVec2,
	"vec3":		inVec3,
	"vec4":		inVec4,
	"int":		inInt,
	"ivec2":	inIVec2,
	"ivec3":	inIVec3,
	"ivec4":	inIVec4,
	"bool":		inBool,
	"bvec2":	inBVec2,
	"bvec3":	inBVec3,
	"bvec4":	inBVec4,
	"mat2":		inMat2,
	"mat3":		inMat3,
	"mat4":		inMat4
}

def genConversionCases(inValueList, convFuncList):
	combinations = list(itertools.product(inValueList, convFuncList))
	return [ConversionCase(inValues, convFunc) for (inValues, convFunc) in combinations]

allCases = []

# Vector swizzles.

vectorSwizzleCases = []

# \todo [petri] Uses fixed precision.
for dataType in VECTOR_TYPES:
	scalarSize = getDataTypeScalarSize(dataType)
	precision = "mediump"
	for swizzleComponents in SWIZZLE_NAMES:
		for swizzleIndices in getSwizzlesForWidth(scalarSize):
			swizzle = "".join(map(lambda x: swizzleComponents[x], swizzleIndices))
			#print "%s %s .%s" % (precision, dataType, swizzle)
			caseName = "%s_%s_%s" % (precision, dataType, swizzle)
			inputs = INPUTS[dataType]
			outputs = map(lambda x: x.swizzle(swizzleIndices), inputs)
			outType = outputs[0].typeString()
			vectorSwizzleCases.append(SwizzleCase(caseName, precision, dataType, swizzle, [("%s in0" % dataType, inputs)], [("%s out0" % outType, outputs)]))

# ??
#for dataType in VECTOR_TYPES:
#	scalarSize = getDataTypeScalarSize(dataType)
#	for precision in PRECISION_TYPES:
#		for swizzleIndices in getSwizzlesForWidth(scalarSize):
#			swizzle = "".join(map(lambda x: "xyzw"[x], swizzleIndices))
#			#print "%s %s .%s" % (precision, dataType, swizzle)
#			caseName = "%s_%s_%s" % (precision, dataType, swizzle)
#			inputs = INPUTS[dataType]
#			outputs = map(lambda x: x.swizzle(swizzleIndices), inputs)
#			vectorSwizzleCases.append(SwizzleCase(caseName, precision, dataType, swizzle, [("in0", inputs)], [("out0", outputs)]))

allCases.append(CaseGroup("vector_swizzles", "Vector Swizzles", vectorSwizzleCases))

# Swizzles:
# - vector components
#   * int, float, bool vectors
#   * .xyzw, .rgba, .stpq
#   * illegal to mix
#   * not allowed for scalar types
#   * legal to chain: vec4.rgba.xyzw.stpq
#   * illegal to select more than 4 components

# TODO: precisions!!

#allCases.append(CaseGroup("vector_swizzles", "Vector Swizzles",
#	genSwizzleCase([inVec2, inVec3, inVec4],

# Main program.

if __name__ == "__main__":
	print "Generating shader case files."
	writeAllCases("swizzles.test", allCases)