"""ttLib.tables.ttProgram.py -- Assembler/disassembler for TrueType bytecode programs."""

from fontTools.misc.textTools import num2binary, binary2num, readHex, strjoin
import array
from io import StringIO
import re
import logging


log = logging.getLogger(__name__)

# first, the list of instructions that eat bytes or words from the instruction stream

streamInstructions = [
#
#	opcode  mnemonic     argBits    descriptive name      pops pushes         eats from instruction stream          pushes
#
	(0x40,	'NPUSHB',	0,	'PushNBytes',		0, -1),	#                      n, b1, b2,...bn      b1,b2...bn
	(0x41,	'NPUSHW',	0,	'PushNWords',		0, -1),	#                       n, w1, w2,...w      w1,w2...wn
	(0xb0,	'PUSHB',	3,	'PushBytes',		0, -1),	#                          b0, b1,..bn  b0, b1, ...,bn
	(0xb8,	'PUSHW',	3,	'PushWords',		0, -1),	#                           w0,w1,..wn   w0 ,w1, ...wn
]


# next,	the list of "normal" instructions

instructions = [
#
#,	opcode  mnemonic     argBits    descriptive name      pops pushes         eats from instruction stream          pushes
#
	(0x7f,	'AA',		0,	'AdjustAngle',		1, 0),	#                                    p               -
	(0x64,	'ABS',		0,	'Absolute',		1, 1),	#                                    n             |n|
	(0x60,	'ADD',		0,	'Add',			2, 1),	#                               n2, n1       (n1 + n2)
	(0x27,	'ALIGNPTS',	0,	'AlignPts',		2, 0),	#                               p2, p1               -
	(0x3c,	'ALIGNRP',	0,	'AlignRelativePt',	-1, 0),	#             p1, p2, ... , ploopvalue               -
	(0x5a,	'AND',		0,	'LogicalAnd',		2, 1),	#                               e2, e1               b
	(0x2b,	'CALL',		0,	'CallFunction',		1, 0),	#                                    f               -
	(0x67,	'CEILING',	0,	'Ceiling',		1, 1),	#                                    n         ceil(n)
	(0x25,	'CINDEX',	0,	'CopyXToTopStack',	1, 1),	#                                    k              ek
	(0x22,	'CLEAR',	0,	'ClearStack',		-1, 0),	#               all items on the stack               -
	(0x4f,	'DEBUG',	0,	'DebugCall',		1, 0),	#                                    n               -
	(0x73,	'DELTAC1',	0,	'DeltaExceptionC1',	-1, 0),	#    argn, cn, argn-1,cn-1, , arg1, c1               -
	(0x74,	'DELTAC2',	0,	'DeltaExceptionC2',	-1, 0),	#    argn, cn, argn-1,cn-1, , arg1, c1               -
	(0x75,	'DELTAC3',	0,	'DeltaExceptionC3',	-1, 0),	#    argn, cn, argn-1,cn-1, , arg1, c1               -
	(0x5d,	'DELTAP1',	0,	'DeltaExceptionP1',	-1, 0),	#   argn, pn, argn-1, pn-1, , arg1, p1               -
	(0x71,	'DELTAP2',	0,	'DeltaExceptionP2',	-1, 0),	#   argn, pn, argn-1, pn-1, , arg1, p1               -
	(0x72,	'DELTAP3',	0,	'DeltaExceptionP3',	-1, 0),	#   argn, pn, argn-1, pn-1, , arg1, p1               -
	(0x24,	'DEPTH',	0,	'GetDepthStack',	0, 1),	#                                    -               n
	(0x62,	'DIV',		0,	'Divide',		2, 1),	#                               n2, n1   (n1 * 64)/ n2
	(0x20,	'DUP',		0,	'DuplicateTopStack',	1, 2),	#                                    e            e, e
	(0x59,	'EIF',		0,	'EndIf',		0, 0),	#                                    -               -
	(0x1b,	'ELSE',		0,	'Else',			0, 0),	#                                    -               -
	(0x2d,	'ENDF',		0,	'EndFunctionDefinition', 0, 0),	#                                    -               -
	(0x54,	'EQ',		0,	'Equal',		2, 1),	#                               e2, e1               b
	(0x57,	'EVEN',		0,	'Even',			1, 1),	#                                    e               b
	(0x2c,	'FDEF',		0,	'FunctionDefinition',	1, 0),	#                                    f               -
	(0x4e,	'FLIPOFF',	0,	'SetAutoFlipOff',	0, 0),	#                                    -               -
	(0x4d,	'FLIPON',	0,	'SetAutoFlipOn',	0, 0),	#                                    -               -
	(0x80,	'FLIPPT',	0,	'FlipPoint',		-1, 0),	#              p1, p2, ..., ploopvalue               -
	(0x82,	'FLIPRGOFF',	0,	'FlipRangeOff',		2, 0),	#                                 h, l               -
	(0x81,	'FLIPRGON',	0,	'FlipRangeOn',		2, 0),	#                                 h, l               -
	(0x66,	'FLOOR',	0,	'Floor',		1, 1),	#                                    n        floor(n)
	(0x46,	'GC',		1,	'GetCoordOnPVector',	1, 1),	#                                    p               c
	(0x88,	'GETINFO',	0,	'GetInfo',		1, 1),	#                             selector          result
        (0x91,  'GETVARIATION', 0,      'GetVariation',         0, -1), #                                    -        a1,..,an
	(0x0d,	'GFV',		0,	'GetFVector',		0, 2),	#                                    -          px, py
	(0x0c,	'GPV',		0,	'GetPVector',		0, 2),	#                                    -          px, py
	(0x52,	'GT',		0,	'GreaterThan',		2, 1),	#                               e2, e1               b
	(0x53,	'GTEQ',		0,	'GreaterThanOrEqual',	2, 1),	#                               e2, e1               b
	(0x89,	'IDEF',		0,	'InstructionDefinition', 1, 0),	#                                    f               -
	(0x58,	'IF',		0,	'If',			1, 0),	#                                    e               -
	(0x8e,	'INSTCTRL',	0,	'SetInstrExecControl',	2, 0),	#                                 s, v               -
	(0x39,	'IP',		0,	'InterpolatePts',	-1, 0),	#             p1, p2, ... , ploopvalue               -
	(0x0f,	'ISECT',	0,	'MovePtToIntersect',	5, 0),	#                    a1, a0, b1, b0, p               -
	(0x30,	'IUP',		1,	'InterpolateUntPts',	0, 0),	#                                    -               -
	(0x1c,	'JMPR',		0,	'Jump',			1, 0),	#                               offset               -
	(0x79,	'JROF',		0,	'JumpRelativeOnFalse',	2, 0),	#                            e, offset               -
	(0x78,	'JROT',		0,	'JumpRelativeOnTrue',	2, 0),	#                            e, offset               -
	(0x2a,	'LOOPCALL',	0,	'LoopAndCallFunction',	2, 0),	#                             f, count               -
	(0x50,	'LT',		0,	'LessThan',		2, 1),	#                               e2, e1               b
	(0x51,	'LTEQ',		0,	'LessThenOrEqual',	2, 1),	#                               e2, e1               b
	(0x8b,	'MAX',		0,	'Maximum',		2, 1),	#                               e2, e1     max(e1, e2)
	(0x49,	'MD',		1,	'MeasureDistance',	2, 1),	#                                p2,p1               d
	(0x2e,	'MDAP',		1,	'MoveDirectAbsPt',	1, 0),	#                                    p               -
	(0xc0,	'MDRP',		5,	'MoveDirectRelPt',	1, 0),	#                                    p               -
	(0x3e,	'MIAP',		1,	'MoveIndirectAbsPt',	2, 0),	#                                 n, p               -
	(0x8c,	'MIN',		0,	'Minimum',		2, 1),	#                               e2, e1     min(e1, e2)
	(0x26,	'MINDEX',	0,	'MoveXToTopStack',	1, 1),	#                                    k              ek
	(0xe0,	'MIRP',		5,	'MoveIndirectRelPt',	2, 0),	#                                 n, p               -
	(0x4b,	'MPPEM',	0,	'MeasurePixelPerEm',	0, 1),	#                                    -            ppem
	(0x4c,	'MPS',		0,	'MeasurePointSize',	0, 1),	#                                    -       pointSize
	(0x3a,	'MSIRP',	1,	'MoveStackIndirRelPt',	2, 0),	#                                 d, p               -
	(0x63,	'MUL',		0,	'Multiply',		2, 1),	#                               n2, n1    (n1 * n2)/64
	(0x65,	'NEG',		0,	'Negate',		1, 1),	#                                    n              -n
	(0x55,	'NEQ',		0,	'NotEqual',		2, 1),	#                               e2, e1               b
	(0x5c,	'NOT',		0,	'LogicalNot',		1, 1),	#                                    e       ( not e )
	(0x6c,	'NROUND',	2,	'NoRound',		1, 1),	#                                   n1              n2
	(0x56,	'ODD',		0,	'Odd',			1, 1),	#                                    e               b
	(0x5b,	'OR',		0,	'LogicalOr',		2, 1),	#                               e2, e1               b
	(0x21,	'POP',		0,	'PopTopStack',		1, 0),	#                                    e               -
	(0x45,	'RCVT',		0,	'ReadCVT',		1, 1),	#                             location           value
	(0x7d,	'RDTG',		0,	'RoundDownToGrid',	0, 0),	#                                    -               -
	(0x7a,	'ROFF',		0,	'RoundOff',		0, 0),	#                                    -               -
	(0x8a,	'ROLL',		0,	'RollTopThreeStack',	3, 3),	#                                a,b,c           b,a,c
	(0x68,	'ROUND',	2,	'Round',		1, 1),	#                                   n1              n2
	(0x43,	'RS',		0,	'ReadStore',		1, 1),	#                                    n               v
	(0x3d,	'RTDG',		0,	'RoundToDoubleGrid',	0, 0),	#                                    -               -
	(0x18,	'RTG',		0,	'RoundToGrid',		0, 0),	#                                    -               -
	(0x19,	'RTHG',		0,	'RoundToHalfGrid',	0, 0),	#                                    -               -
	(0x7c,	'RUTG',		0,	'RoundUpToGrid',	0, 0),	#                                    -               -
	(0x77,	'S45ROUND',	0,	'SuperRound45Degrees',	1, 0),	#                                    n               -
	(0x7e,	'SANGW',	0,	'SetAngleWeight',	1, 0),	#                               weight               -
	(0x85,	'SCANCTRL',	0,	'ScanConversionControl', 1, 0),	#                                    n               -
	(0x8d,	'SCANTYPE',	0,	'ScanType',		1, 0),	#                                    n               -
	(0x48,	'SCFS',		0,	'SetCoordFromStackFP',	2, 0),	#                                 c, p               -
	(0x1d,	'SCVTCI',	0,	'SetCVTCutIn',		1, 0),	#                                    n               -
	(0x5e,	'SDB',		0,	'SetDeltaBaseInGState',	1, 0),	#                                    n               -
	(0x86,	'SDPVTL',	1,	'SetDualPVectorToLine',	2, 0),	#                               p2, p1               -
	(0x5f,	'SDS',		0,	'SetDeltaShiftInGState',1, 0),	#                                    n               -
	(0x0b,	'SFVFS',	0,	'SetFVectorFromStack',	2, 0),	#                                 y, x               -
	(0x04,	'SFVTCA',	1,	'SetFVectorToAxis',	0, 0),	#                                    -               -
	(0x08,	'SFVTL',	1,	'SetFVectorToLine',	2, 0),	#                               p2, p1               -
	(0x0e,	'SFVTPV',	0,	'SetFVectorToPVector',	0, 0),	#                                    -               -
	(0x34,	'SHC',		1,	'ShiftContourByLastPt',	1, 0),	#                                    c               -
	(0x32,	'SHP',		1,	'ShiftPointByLastPoint',-1, 0),	#              p1, p2, ..., ploopvalue               -
	(0x38,	'SHPIX',	0,	'ShiftZoneByPixel',	-1, 0),	#           d, p1, p2, ..., ploopvalue               -
	(0x36,	'SHZ',		1,	'ShiftZoneByLastPoint',	1, 0),	#                                    e               -
	(0x17,	'SLOOP',	0,	'SetLoopVariable',	1, 0),	#                                    n               -
	(0x1a,	'SMD',		0,	'SetMinimumDistance',	1, 0),	#                             distance               -
	(0x0a,	'SPVFS',	0,	'SetPVectorFromStack',	2, 0),	#                                 y, x               -
	(0x02,	'SPVTCA',	1,	'SetPVectorToAxis',	0, 0),	#                                    -               -
	(0x06,	'SPVTL',	1,	'SetPVectorToLine',	2, 0),	#                               p2, p1               -
	(0x76,	'SROUND',	0,	'SuperRound',		1, 0),	#                                    n               -
	(0x10,	'SRP0',		0,	'SetRefPoint0',		1, 0),	#                                    p               -
	(0x11,	'SRP1',		0,	'SetRefPoint1',		1, 0),	#                                    p               -
	(0x12,	'SRP2',		0,	'SetRefPoint2',		1, 0),	#                                    p               -
	(0x1f,	'SSW',		0,	'SetSingleWidth',	1, 0),	#                                    n               -
	(0x1e,	'SSWCI',	0,	'SetSingleWidthCutIn',	1, 0),	#                                    n               -
	(0x61,	'SUB',		0,	'Subtract',		2, 1),	#                               n2, n1       (n1 - n2)
	(0x00,	'SVTCA',	1,	'SetFPVectorToAxis',	0, 0),	#                                    -               -
	(0x23,	'SWAP',		0,	'SwapTopStack',		2, 2),	#                               e2, e1          e1, e2
	(0x13,	'SZP0',		0,	'SetZonePointer0',	1, 0),	#                                    n               -
	(0x14,	'SZP1',		0,	'SetZonePointer1',	1, 0),	#                                    n               -
	(0x15,	'SZP2',		0,	'SetZonePointer2',	1, 0),	#                                    n               -
	(0x16,	'SZPS',		0,	'SetZonePointerS',	1, 0),	#                                    n               -
	(0x29,	'UTP',		0,	'UnTouchPt',		1, 0),	#                                    p               -
	(0x70,	'WCVTF',	0,	'WriteCVTInFUnits',	2, 0),	#                                 n, l               -
	(0x44,	'WCVTP',	0,	'WriteCVTInPixels',	2, 0),	#                                 v, l               -
	(0x42,	'WS',		0,	'WriteStore',		2, 0),	#                                 v, l               -
]


def bitRepr(value, bits):
	s = ""
	for i in range(bits):
		s = "01"[value & 0x1] + s
		value = value >> 1
	return s


_mnemonicPat = re.compile(r"[A-Z][A-Z0-9]*$")

def _makeDict(instructionList):
	opcodeDict = {}
	mnemonicDict = {}
	for op, mnemonic, argBits, name, pops, pushes in instructionList:
		assert _mnemonicPat.match(mnemonic)
		mnemonicDict[mnemonic] = op, argBits, name
		if argBits:
			argoffset = op
			for i in range(1 << argBits):
				opcodeDict[op+i] = mnemonic, argBits, argoffset, name
		else:
				opcodeDict[op] = mnemonic, 0, 0, name
	return opcodeDict, mnemonicDict

streamOpcodeDict, streamMnemonicDict = _makeDict(streamInstructions)
opcodeDict, mnemonicDict = _makeDict(instructions)

class tt_instructions_error(Exception):
	def __init__(self, error):
		self.error = error
	def __str__(self):
		return "TT instructions error: %s" % repr(self.error)


_comment = r"/\*.*?\*/"
_instruction = r"([A-Z][A-Z0-9]*)\s*\[(.*?)\]"
_number = r"-?[0-9]+"
_token = "(%s)|(%s)|(%s)" % (_instruction, _number, _comment)

_tokenRE = re.compile(_token)
_whiteRE = re.compile(r"\s*")

_pushCountPat = re.compile(r"[A-Z][A-Z0-9]*\s*\[.*?\]\s*/\* ([0-9]+).*?\*/")

_indentRE = re.compile(r"^FDEF|IF|ELSE\[ \]\t.+")
_unindentRE = re.compile(r"^ELSE|ENDF|EIF\[ \]\t.+")

def _skipWhite(data, pos):
	m = _whiteRE.match(data, pos)
	newPos = m.regs[0][1]
	assert newPos >= pos
	return newPos


class Program(object):

	def __init__(self):
		pass

	def fromBytecode(self, bytecode):
		self.bytecode = array.array("B", bytecode)
		if hasattr(self, "assembly"):
			del self.assembly

	def fromAssembly(self, assembly):
		self.assembly = assembly
		if hasattr(self, "bytecode"):
			del self.bytecode

	def getBytecode(self):
		if not hasattr(self, "bytecode"):
			self._assemble()
		return self.bytecode.tobytes()

	def getAssembly(self, preserve=True):
		if not hasattr(self, "assembly"):
			self._disassemble(preserve=preserve)
		return self.assembly

	def toXML(self, writer, ttFont):
		if not hasattr (ttFont, "disassembleInstructions") or ttFont.disassembleInstructions:
			try:
				assembly = self.getAssembly()
			except:
				import traceback
				tmp = StringIO()
				traceback.print_exc(file=tmp)
				msg = "An exception occurred during the decompilation of glyph program:\n\n"
				msg += tmp.getvalue()
				log.error(msg)
				writer.begintag("bytecode")
				writer.newline()
				writer.comment(msg.strip())
				writer.newline()
				writer.dumphex(self.getBytecode())
				writer.endtag("bytecode")
				writer.newline()
			else:
				if not assembly:
					return
				writer.begintag("assembly")
				writer.newline()
				i = 0
				indent = 0
				nInstr = len(assembly)
				while i < nInstr:
					instr = assembly[i]
					if _unindentRE.match(instr):
						indent -= 1
					writer.write(writer.indentwhite * indent)
					writer.write(instr)
					writer.newline()
					m = _pushCountPat.match(instr)
					i = i + 1
					if m:
						nValues = int(m.group(1))
						line = []
						j = 0
						for j in range(nValues):
							if j and not (j % 25):
								writer.write(writer.indentwhite * indent)
								writer.write(' '.join(line))
								writer.newline()
								line = []
							line.append(assembly[i+j])
						writer.write(writer.indentwhite * indent)
						writer.write(' '.join(line))
						writer.newline()
						i = i + j + 1
					if _indentRE.match(instr):
						indent += 1
				writer.endtag("assembly")
				writer.newline()
		else:
			bytecode = self.getBytecode()
			if not bytecode:
				return
			writer.begintag("bytecode")
			writer.newline()
			writer.dumphex(bytecode)
			writer.endtag("bytecode")
			writer.newline()

	def fromXML(self, name, attrs, content, ttFont):
		if name == "assembly":
			self.fromAssembly(strjoin(content))
			self._assemble()
			del self.assembly
		else:
			assert name == "bytecode"
			self.fromBytecode(readHex(content))

	def _assemble(self):
		assembly = getattr(self, 'assembly', [])
		if isinstance(assembly, type([])):
			assembly = ' '.join(assembly)
		bytecode = []
		push = bytecode.append
		lenAssembly = len(assembly)
		pos = _skipWhite(assembly, 0)
		while pos < lenAssembly:
			m = _tokenRE.match(assembly, pos)
			if m is None:
				raise tt_instructions_error("Syntax error in TT program (%s)" % assembly[pos-5:pos+15])
			dummy, mnemonic, arg, number, comment = m.groups()
			pos = m.regs[0][1]
			if comment:
				pos = _skipWhite(assembly, pos)
				continue

			arg = arg.strip()
			if mnemonic.startswith("INSTR"):
				# Unknown instruction
				op = int(mnemonic[5:])
				push(op)
			elif mnemonic not in ("PUSH", "NPUSHB", "NPUSHW", "PUSHB", "PUSHW"):
				op, argBits, name = mnemonicDict[mnemonic]
				if len(arg) != argBits:
					raise tt_instructions_error("Incorrect number of argument bits (%s[%s])" % (mnemonic, arg))
				if arg:
					arg = binary2num(arg)
					push(op + arg)
				else:
					push(op)
			else:
				args = []
				pos = _skipWhite(assembly, pos)
				while pos < lenAssembly:
					m = _tokenRE.match(assembly, pos)
					if m is None:
						raise tt_instructions_error("Syntax error in TT program (%s)" % assembly[pos:pos+15])
					dummy, _mnemonic, arg, number, comment = m.groups()
					if number is None and comment is None:
						break
					pos = m.regs[0][1]
					pos = _skipWhite(assembly, pos)
					if comment is not None:
						continue
					args.append(int(number))
				nArgs = len(args)
				if mnemonic == "PUSH":
					# Automatically choose the most compact representation
					nWords = 0
					while nArgs:
						while nWords < nArgs and nWords < 255 and not (0 <= args[nWords] <= 255):
							nWords += 1
						nBytes = 0
						while nWords+nBytes < nArgs and nBytes < 255 and 0 <= args[nWords+nBytes] <= 255:
							nBytes += 1
						if nBytes < 2 and nWords + nBytes < 255 and nWords + nBytes != nArgs:
							# Will write bytes as words
							nWords += nBytes
							continue

						# Write words
						if nWords:
							if nWords <= 8:
								op, argBits, name = streamMnemonicDict["PUSHW"]
								op = op + nWords - 1
								push(op)
							else:
								op, argBits, name = streamMnemonicDict["NPUSHW"]
								push(op)
								push(nWords)
							for value in args[:nWords]:
								assert -32768 <= value < 32768, "PUSH value out of range %d" % value
								push((value >> 8) & 0xff)
								push(value & 0xff)

						# Write bytes
						if nBytes:
							pass
							if nBytes <= 8:
								op, argBits, name = streamMnemonicDict["PUSHB"]
								op = op + nBytes - 1
								push(op)
							else:
								op, argBits, name = streamMnemonicDict["NPUSHB"]
								push(op)
								push(nBytes)
							for value in args[nWords:nWords+nBytes]:
								push(value)

						nTotal = nWords + nBytes
						args = args[nTotal:]
						nArgs -= nTotal
						nWords = 0
				else:
					# Write exactly what we've been asked to
					words = mnemonic[-1] == "W"
					op, argBits, name = streamMnemonicDict[mnemonic]
					if mnemonic[0] != "N":
						assert nArgs <= 8, nArgs
						op = op + nArgs - 1
						push(op)
					else:
						assert nArgs < 256
						push(op)
						push(nArgs)
					if words:
						for value in args:
							assert -32768 <= value < 32768, "PUSHW value out of range %d" % value
							push((value >> 8) & 0xff)
							push(value & 0xff)
					else:
						for value in args:
							assert 0 <= value < 256, "PUSHB value out of range %d" % value
							push(value)

			pos = _skipWhite(assembly, pos)

		if bytecode:
			assert max(bytecode) < 256 and min(bytecode) >= 0
		self.bytecode = array.array("B", bytecode)

	def _disassemble(self, preserve=False):
		assembly = []
		i = 0
		bytecode = getattr(self, 'bytecode', [])
		numBytecode = len(bytecode)
		while i < numBytecode:
			op = bytecode[i]
			try:
				mnemonic, argBits, argoffset, name = opcodeDict[op]
			except KeyError:
				if op in streamOpcodeDict:
					values = []

					# Merge consecutive PUSH operations
					while bytecode[i] in streamOpcodeDict:
						op = bytecode[i]
						mnemonic, argBits, argoffset, name = streamOpcodeDict[op]
						words = mnemonic[-1] == "W"
						if argBits:
							nValues = op - argoffset + 1
						else:
							i = i + 1
							nValues = bytecode[i]
						i = i + 1
						assert nValues > 0
						if not words:
							for j in range(nValues):
								value = bytecode[i]
								values.append(repr(value))
								i = i + 1
						else:
							for j in range(nValues):
								# cast to signed int16
								value = (bytecode[i] << 8) | bytecode[i+1]
								if value >= 0x8000:
									value = value - 0x10000
								values.append(repr(value))
								i = i + 2
						if preserve:
							break

					if not preserve:
						mnemonic = "PUSH"
					nValues = len(values)
					if nValues == 1:
						assembly.append("%s[ ]	/* 1 value pushed */" % mnemonic)
					else:
						assembly.append("%s[ ]	/* %s values pushed */" % (mnemonic, nValues))
					assembly.extend(values)
				else:
					assembly.append("INSTR%d[ ]" % op)
					i = i + 1
			else:
				if argBits:
					assembly.append(mnemonic + "[%s]	/* %s */" % (num2binary(op - argoffset, argBits), name))
				else:
					assembly.append(mnemonic + "[ ]	/* %s */" % name)
				i = i + 1
		self.assembly = assembly

	def __bool__(self):
		"""
		>>> p = Program()
		>>> bool(p)
		False
		>>> bc = array.array("B", [0])
		>>> p.fromBytecode(bc)
		>>> bool(p)
		True
		>>> p.bytecode.pop()
		0
		>>> bool(p)
		False

		>>> p = Program()
		>>> asm = ['SVTCA[0]']
		>>> p.fromAssembly(asm)
		>>> bool(p)
		True
		>>> p.assembly.pop()
		'SVTCA[0]'
		>>> bool(p)
		False
		"""
		return ((hasattr(self, 'assembly') and len(self.assembly) > 0) or
				(hasattr(self, 'bytecode') and len(self.bytecode) > 0))

	__nonzero__ = __bool__

	def __eq__(self, other):
		if type(self) != type(other):
			return NotImplemented
		return self.__dict__ == other.__dict__

	def __ne__(self, other):
		result = self.__eq__(other)
		return result if result is NotImplemented else not result


def _test():
	"""
		>>> _test()
		True
	"""

	bc = b"""@;:9876543210/.-,+*)(\'&%$#"! \037\036\035\034\033\032\031\030\027\026\025\024\023\022\021\020\017\016\015\014\013\012\011\010\007\006\005\004\003\002\001\000,\001\260\030CXEj\260\031C`\260F#D#\020 \260FN\360M/\260\000\022\033!#\0213Y-,\001\260\030CX\260\005+\260\000\023K\260\024PX\261\000@8Y\260\006+\033!#\0213Y-,\001\260\030CXN\260\003%\020\362!\260\000\022M\033 E\260\004%\260\004%#Jad\260(RX!#\020\326\033\260\003%\020\362!\260\000\022YY-,\260\032CX!!\033\260\002%\260\002%I\260\003%\260\003%Ja d\260\020PX!!!\033\260\003%\260\003%I\260\000PX\260\000PX\270\377\3428!\033\260\0208!Y\033\260\000RX\260\0368!\033\270\377\3608!YYYY-,\001\260\030CX\260\005+\260\000\023K\260\024PX\271\000\000\377\3008Y\260\006+\033!#\0213Y-,N\001\212\020\261F\031CD\260\000\024\261\000F\342\260\000\025\271\000\000\377\3608\000\260\000<\260(+\260\002%\020\260\000<-,\001\030\260\000/\260\001\024\362\260\001\023\260\001\025M\260\000\022-,\001\260\030CX\260\005+\260\000\023\271\000\000\377\3408\260\006+\033!#\0213Y-,\001\260\030CXEdj#Edi\260\031Cd``\260F#D#\020 \260F\360/\260\000\022\033!! \212 \212RX\0213\033!!YY-,\001\261\013\012C#Ce\012-,\000\261\012\013C#C\013-,\000\260F#p\261\001F>\001\260F#p\261\002FE:\261\002\000\010\015-,\260\022+\260\002%E\260\002%Ej\260@\213`\260\002%#D!!!-,\260\023+\260\002%E\260\002%Ej\270\377\300\214`\260\002%#D!!!-,\260\000\260\022+!!!-,\260\000\260\023+!!!-,\001\260\006C\260\007Ce\012-, i\260@a\260\000\213 \261,\300\212\214\270\020\000b`+\014d#da\\X\260\003aY-,\261\000\003%EhT\260\034KPZX\260\003%E\260\003%E`h \260\004%#D\260\004%#D\033\260\003% Eh \212#D\260\003%Eh`\260\003%#DY-,\260\003% Eh \212#D\260\003%Edhe`\260\004%\260\001`#D-,\260\011CX\207!\300\033\260\022CX\207E\260\021+\260G#D\260Gz\344\033\003\212E\030i \260G#D\212\212\207 \260\240QX\260\021+\260G#D\260Gz\344\033!\260Gz\344YYY\030-, \212E#Eh`D-,EjB-,\001\030/-,\001\260\030CX\260\004%\260\004%Id#Edi\260@\213a \260\200bj\260\002%\260\002%a\214\260\031C`\260F#D!\212\020\260F\366!\033!!!!Y-,\001\260\030CX\260\002%E\260\002%Ed`j\260\003%Eja \260\004%Ej \212\213e\260\004%#D\214\260\003%#D!!\033 EjD EjDY-,\001 E\260\000U\260\030CZXEh#Ei\260@\213a \260\200bj \212#a \260\003%\213e\260\004%#D\214\260\003%#D!!\033!!\260\031+Y-,\001\212\212Ed#EdadB-,\260\004%\260\004%\260\031+\260\030CX\260\004%\260\004%\260\003%\260\033+\001\260\002%C\260@T\260\002%C\260\000TZX\260\003% E\260@aDY\260\002%C\260\000T\260\002%C\260@TZX\260\004% E\260@`DYY!!!!-,\001KRXC\260\002%E#aD\033!!Y-,\001KRXC\260\002%E#`D\033!!Y-,KRXED\033!!Y-,\001 \260\003%#I\260@`\260 c \260\000RX#\260\002%8#\260\002%e8\000\212c8\033!!!!!Y\001-,KPXED\033!!Y-,\001\260\005%\020# \212\365\000\260\001`#\355\354-,\001\260\005%\020# \212\365\000\260\001a#\355\354-,\001\260\006%\020\365\000\355\354-,F#F`\212\212F# F\212`\212a\270\377\200b# \020#\212\261KK\212pE` \260\000PX\260\001a\270\377\272\213\033\260F\214Y\260\020`h\001:-, E\260\003%FRX\260\002%F ha\260\003%\260\003%?#!8\033!\021Y-, E\260\003%FPX\260\002%F ha\260\003%\260\003%?#!8\033!\021Y-,\000\260\007C\260\006C\013-,\212\020\354-,\260\014CX!\033 F\260\000RX\270\377\3608\033\260\0208YY-, \260\000UX\270\020\000c\260\003%Ed\260\003%Eda\260\000SX\260\002\033\260@a\260\003Y%EiSXED\033!!Y\033!\260\002%E\260\002%Ead\260(QXED\033!!YY-,!!\014d#d\213\270@\000b-,!\260\200QX\014d#d\213\270 \000b\033\262\000@/+Y\260\002`-,!\260\300QX\014d#d\213\270\025Ub\033\262\000\200/+Y\260\002`-,\014d#d\213\270@\000b`#!-,KSX\260\004%\260\004%Id#Edi\260@\213a \260\200bj\260\002%\260\002%a\214\260F#D!\212\020\260F\366!\033!\212\021#\022 9/Y-,\260\002%\260\002%Id\260\300TX\270\377\3708\260\0108\033!!Y-,\260\023CX\003\033\002Y-,\260\023CX\002\033\003Y-,\260\012+#\020 <\260\027+-,\260\002%\270\377\3608\260(+\212\020# \320#\260\020+\260\005CX\300\033<Y \020\021\260\000\022\001-,KS#KQZX8\033!!Y-,\001\260\002%\020\320#\311\001\260\001\023\260\000\024\020\260\001<\260\001\026-,\001\260\000\023\260\001\260\003%I\260\003\0278\260\001\023-,KS#KQZX E\212`D\033!!Y-, 9/-"""

	p = Program()
	p.fromBytecode(bc)
	asm = p.getAssembly(preserve=True)
	p.fromAssembly(asm)
	print(bc == p.getBytecode())

if __name__ == "__main__":
	import sys
	import doctest
	sys.exit(doctest.testmod().failed)
