import string

import types

import sys

import os

import copy

try:

	from xml.parsers import xmllib

	_xmllib_newStyle = 1

except ImportError:

	import xmllib

	_xmllib_newStyle = 0

from reportlab.lib.colors import stringToColor, white, black, red, Color

from reportlab.lib.fonts import tt2ps, ps2tt

sizeDelta = 2		# amount to reduce font size by for super and sub script

subFraction = 0.5	# fraction of font size that a sub script should be lowered

superFraction = 0.5	# fraction of font size that a super script should be raised

def _num(s):

	try:

		return int(s)

	except ValueError:

		return float(s)

#characters not supported: epsi, Gammad, gammad, kappav, rhov, Upsi, upsi

greeks = {

	'alpha':'a',

	'beta':'b',

	'chi':'c',

	'Delta':'D',

	'delta':'d',

	'epsiv':'e',

	'eta':'h',

	'Gamma':'G',

	'gamma':'g',

	'iota':'i',

	'kappa':'k',

	'Lambda':'L',

	'lambda':'l',

	'mu':'m',

	'nu':'n',

	'Omega':'W',

	'omega':'w',

	'omicron':'x',

	'Phi':'F',

	'phi':'f',

	'phiv':'j',

	'Pi':'P',

	'pi':'p',

	'piv':'v',

	'Psi':'Y',

	'psi':'y',

	'rho':'r',

	'Sigma':'S',

	'sigma':'s',

	'sigmav':'V',

	'tau':'t',

	'Theta':'Q',

	'theta':'q',

	'thetav':'j',

	'Xi':'X',

	'xi':'x',

	'zeta':'z'

}

#------------------------------------------------------------------------

class ParaFrag:

	"""class ParaFrag contains the intermediate representation of string

	segments as they are being parsed by the XMLParser.

	"""

	def __init__(self,**attr):

		for k,v in attr.items():

			setattr(self,k,v)

	def clone(self,**attr):

		n = apply(ParaFrag,(),self.__dict__)

		if attr != {}: apply(ParaFrag.__init__,(n,),attr)

		return n

#------------------------------------------------------------------

# The ParaFormatter will be able to format the following xml

# tags:

#	   < b > < /b > - bold

#	   < i > < /i > - italics

#	   < u > < /u > - underline

#	   < super > < /super > - superscript

#	   < sub > < /sub > - subscript

#	   <font name=fontfamily/fontname color=colorname size=float>

#

# It will also be able to handle any MathML specified Greek characters.

#------------------------------------------------------------------

class ParaParser(xmllib.XMLParser):

	#----------------------------------------------------------

	# First we will define all of the xml tag handler functions.

	#

	# start_<tag>(attributes)

	# end_<tag>()

	#

	# While parsing the xml ParaFormatter will call these

	# functions to handle the string formatting tags.

	# At the start of each tag the corresponding field will

	# be set to 1 and at the end tag the corresponding field will

	# be set to 0.	Then when handle_data is called the options

	# for that data will be aparent by the current settings.

	#----------------------------------------------------------

	#### bold

	def start_b( self, attributes ):

		self._push(bold=1)

	def end_b( self ):

		self._pop(bold=1)

	#### italics

	def start_i( self, attributes ):

		self._push(italic=1)

	def end_i( self ):

		self._pop(italic=1)

	#### underline

	def start_u( self, attributes ):

		self._push(underline=1)

	def end_u( self ):

		self._pop(underline=1)

	#### super script

	def start_super( self, attributes ):

		self._push(super=1)

	def end_super( self ):

		self._pop(super=1)

	#### sub script

	def start_sub( self, attributes ):

		self._push(sub=1)

	def end_sub( self ):

		self._pop(sub=1)

	#### greek script

	if _xmllib_newStyle:

		def handle_entityref(self,name):

			if greeks.has_key(name):

				self._push(greek=1)

				self.handle_data(greeks[name])

				self._pop(greek=1)

			else:

				xmllib.XMLParser.handle_entityref(self,name)

	else:

		def start_greekLetter(self, attributes,letter):

			self._push(greek=1)

			self.handle_data(letter)

	def start_greek(self, attributes):

		self._push(greek=1)

	def end_greek(self):

		self._pop(greek=1)

	#things which are valid font attributes

	_fontAttrMap = {'size': ('fontSize',_num),

					'name': ('fontName', None),

					'color':('textColor',stringToColor)}

	def start_font(self,attr):

		A = {}

		for i, j in self._fontAttrMap.items():

			if attr.has_key(i):

				func = j[1]

				val  = attr[i]

				try:

					A[j[0]] = (func is None) and val or apply(func,(val,))

				except:

					self.syntax_error('%s: invalid value %s'%(i,val))

		apply(self._push,(),A)

	def end_font(self):

		self._pop()

	def _push(self,**kw):

		frag = copy.copy(self._stack[-1])

		for k, v in kw.items():

			setattr(frag,k,v)

		self._stack.append(frag)

	def _pop(self,**kw):

		frag = self._stack[-1]

		del self._stack[-1]

		for k, v in kw.items():

			assert getattr(frag,k)==v

		return frag

	#----------------------------------------------------------------

	def __init__(self,verbose=0):

		if _xmllib_newStyle:

			xmllib.XMLParser.__init__(self,verbose=verbose)

		else:

			xmllib.XMLParser.__init__(self)

			# set up handlers for various tags

			self.elements = {	'b': (self.start_b, self.end_b),

							'u': (self.start_u, self.end_u),

							'i': (self.start_i, self.end_i),

							'super': (self.start_super, self.end_super),

							'sub': (self.start_sub, self.end_sub),

							'font': (self.start_font, self.end_font),

							'greek': (self.start_greek, self.end_greek)

							}

			# automatically add handlers for all of the greek characters

			for item in greeks.keys():

				self.elements[item] = (lambda attr,self=self,letter=greeks[item]:

					self.start_greekLetter(attr,letter), self.end_greek)

			# set up dictionary for greek characters, this is a class variable

			self.entitydefs = copy.copy(self.entitydefs)

			for item in greeks.keys():

				self.entitydefs[item] = '<%s/>' % item

	def _reset(self, style):

		'''reset the parser'''

		xmllib.XMLParser.reset(self)

		# initialize list of string segments to empty

		self.errors = []

		self.fragList = []

		# initialize frag values

		frag = ParaFrag()

		frag.sub = 0

		frag.super = 0

		frag.rise = 0

		frag.fontName, frag.bold, frag.italic = ps2tt(style.fontName)

		frag.fontSize = style.fontSize

		frag.underline = 0

		frag.greek = 0

		frag.textColor = style.textColor

		self._stack = [frag]

	def syntax_error(self,message):

		if message[:11]=="attribute `" and message[-18:]=="' value not quoted": return

		self.errors.append(message)

	#----------------------------------------------------------------

	def handle_data(self,data):

		"Creates an intermediate representation of string segments."

		frag = copy.copy(self._stack[-1])

		#save our data

		frag.text = data

		# if sub and super are both one they will cancel each other out

		if frag.sub == 1 and frag.super == 1:

			frag.sub = 0

			frag.super = 0

		if frag.sub:

			frag.rise = -frag.fontSize*subFraction

			frag.fontSize = max(frag.fontSize-sizeDelta,3)

			frag.rise = frag.fontSize*superFraction

		if frag.greek: frag.fontName = 'symbol'

		# bold, italic, and underline

		frag.fontName = tt2ps(frag.fontName,frag.bold,frag.italic)

		self.fragList.append(frag)

	#----------------------------------------------------------------

	def parse(self, text, style):

		"""Given a formatted string will return a list of

		ParaFrag objects with their calculated widths.

		If errors occur None will be returned and the

		self.errors holds a list of the error messages.

		"""

		# the xmlparser requires that all text be surrounded by xml

		# tags, therefore we must throw some unused flags around the

		# given string

		self._reset(style)	# reinitialise the parser

		self.feed("<ReportLabParagraph>"+text+"</ReportLabParagraph>")

		self.close()	# force parsing to complete

		if len(self.errors)==0:

			fragList = self.fragList

			self.fragList = []

			return fragList

		else:

			return None

if __name__=='__main__':

	from reportlab.platypus.layout import cleanBlockQuotedText

	_parser=ParaParser()

	style=ParaFrag()

	style.fontName='Times-Roman'

	style.fontSize = 12

	style.textColor = black

	text='''

	<b><i><greek>a</greek>D</i></b>&beta;

	<font name="helvetica" size="15" color=green>

	Tell me, O muse, of that ingenious hero who travelled far and wide

	after</font> he had sacked the famous town of Troy. Many cities did he visit,

	and many were the nations with whose manners and customs he was acquainted;

	moreover he suffered much by sea while trying to save his own life

	and bring his men safely home; but do what he might he could not save

	his men, for they perished through their own sheer folly in eating

	the cattle of the Sun-god Hyperion; so the god prevented them from

	ever reaching home. Tell me, too, about all these things, O daughter

	'''

	text = cleanBlockQuotedText(text)

	rv = _parser.parse(text,style)

	if rv is None:

		for l in _parser.errors:

			print l

	else:

		for l in rv: