import re

REG_STATUS_TO_COLOR = {
	"insert": "green",
	"change": "yellow",
	"remove": "red",
	"none":   "black",
	"jump":   "orange"
}

DEFAULT_OPTIONS = """register_node/.style={rectangle, draw=black!30,
					fill=black!5, very thick, minimum size=0.5,
					minimum width=20mm}, text_node/.style={}"""

class TikzPainter:

	def __init__ (self, registers=None, max_stack_size=8, stack_draw_mode="up", options=None):
		self.registers = registers if registers else REGISTERS
		self.text = []
		self.pos_x = 0
		self.max_stack_size = max_stack_size
		self.stack_draw_mode = stack_draw_mode
		self.options = options if options else DEFAULT_OPTIONS

	def addText (self, str, *args):
		text = re.sub(r"[^\\]%", "\\%", str.format(*args))
		self.text.append(text)

	def getRegColor (self, reg_state):
		return REG_STATUS_TO_COLOR[reg_state]

	def drawStackUpward (self, pos, emu, x):
		base_pointer = emu.getVal('%rbp')

		pos -= 1.5
		base_sp = min(emu.last_sp, emu.getVal('%rsp'))
		pos += 0.5 * max(0, emu.getVal('%rsp')-emu.last_sp)
		assert(isinstance(emu.getVal('%rsp'), (int, long)))
		for index in range(base_sp, 3+min(emu.max_stack_size, emu.getVal('%rsp')+self.max_stack_size)):
			reg_state = emu.regState("m"+str(index))
			reg_dect = "register_node, fill="+self.getRegColor(reg_state)+"!10"
			self.addText("\t\\node[{}]() at ({}, {}){{{}}};\n",
					reg_dect, x, pos, emu.stack[index])
			if base_pointer == index:
				self.addText("\t\\draw ({0},{2}) -- ({1},{2});\n",x-1.1,x+1.1,pos-0.25)
				base_pointer = emu.stack[base_pointer]
			pos -= 0.5
		return pos, x

	def drawStackDownward (self, pos, emu, x):
		pos -= 1
		for index in range(emu.getVal('%rsp')-8, max(emu.last_sp, emu.getVal('%rsp'))):
			reg_state = emu.regState("m"+str(index))
			reg_dect = "register_node, fill="+self.getRegColor(reg_state)+"!10"
			self.addText("\t\\node[{}]() at ({}, {}){{{}}};\n",
					reg_dect, x, pos, emu.stack[index])
			pos -= 0.5
		return pos, x

	def drawState (self, emu, line_nr=None):
		x = (self.pos_x+1)*2.5-0.5
		self.pos_x += 1

		# Draw register cells
		pos = 0.5
		for reg_name in self.registers:
			pos -= 0.5
			if reg_name =="":
				continue
			reg_state = emu.regState(reg_name)
			reg_dect = "register_node, fill="+self.getRegColor(reg_state)+"!10"
			self.addText("\t\\node[{}]() at ({}, {}){{{}}};\n",
					reg_dect, x, pos, emu.getVal(reg_name))

		# Draw stack
		if self.stack_draw_mode == "up":
			pos, x = self.drawStackUpward(pos, emu, x)
		else:
			pos, x = self.drawStackDownward(pos, emu, x)

		# Draw line signature
		if line_nr == None:
			return
		pos = 2
		signature = emu.getLineSignature(line_nr)
		for token in signature:
			self.addText("\t\\node[text_node]() at ({}, {}){{{}}};\n",
						x-1.25, pos, token)
			pos -= 0.5

	def drawNames (self, emu):
		x = 0
		pos = 0
		for reg_name in self.registers:
			self.addText("\t\\node[text_node]() at ({}, {}){{{}}};\n",
						x, pos, reg_name[1:])
			pos -= 0.5

		# Draw stack
		if self.stack_draw_mode == "up":
			self.drawStackNamesUpward(pos, emu, x)
		else:
			self.drawStackNamesDownward(pos, emu, x)

	def drawStackNamesUpward (self, pos, emu, x):
		self.addText("\t\\node[text_node]() at ({}, {}){{TOS+1}};\n",
					x, pos-0.5)
		self.addText("\t\\node[text_node]() at ({}, {}){{TOS}};\n",
					x, pos-1.0)
		pos -= 1
		for index in range(1,self.max_stack_size):
			pos -= 0.5
			self.addText("\t\\node[text_node]() at ({}, {}){{TOS-{}}};\n",
						x, pos, index)

	def to_string (self):
		PRE = """ \\documentclass{standalone}
				  \\usepackage{tikz}
				  \\begin{document}
				  \\begin{tikzpicture}["""+self.options+"]"
		POST = """\\end{tikzpicture}
				  \\end{document}"""
		return PRE + "".join(self.text) + POST

	def __str__ (self):
		return 'TikzPainter[]'