#Copyright ReportLab Europe Ltd. 2000-2012 #see license.txt for license details #history http://www.reportlab.co.uk/cgi-bin/viewcvs.cgi/public/reportlab/trunk/reportlab/platypus/flowables.py __version__=''' $Id$ ''' __doc__=""" A flowable is a "floating element" in a document whose exact position is determined by the other elements that precede it, such as a paragraph, a diagram interspersed between paragraphs, a section header, etcetera. Examples of non-flowables include page numbering annotations, headers, footers, fixed diagrams or logos, among others. Flowables are defined here as objects which know how to determine their size and which can draw themselves onto a page with respect to a relative "origin" position determined at a higher level. The object's draw() method should assume that (0,0) corresponds to the bottom left corner of the enclosing rectangle that will contain the object. The attributes vAlign and hAlign may be used by 'packers' as hints as to how the object should be placed. Some Flowables also know how to "split themselves". For example a long paragraph might split itself between one page and the next. Packers should set the canv attribute during wrap, split & draw operations to allow the flowable to work out sizes etc in the proper context. The "text" of a document usually consists mainly of a sequence of flowables which flow into a document from top to bottom (with column and page breaks controlled by higher level components). """ import os from copy import deepcopy, copy from reportlab.lib.colors import red, gray, lightgrey from reportlab.lib.rl_accel import fp_str from reportlab.lib.enums import TA_LEFT, TA_CENTER, TA_RIGHT, TA_JUSTIFY from reportlab.lib.styles import _baseFontName from reportlab.lib.utils import strTypes from reportlab.pdfbase import pdfutils from reportlab.pdfbase.pdfmetrics import stringWidth from reportlab.rl_config import _FUZZ, overlapAttachedSpace, ignoreContainerActions, listWrapOnFakeWidth import collections __all__=('TraceInfo','Flowable','XBox','Preformatted','Image','Spacer','PageBreak','SlowPageBreak', 'CondPageBreak','KeepTogether','Macro','CallerMacro','ParagraphAndImage', 'FailOnWrap','HRFlowable','PTOContainer','KeepInFrame','UseUpSpace', 'ListFlowable','ListItem','DDIndenter','LIIndenter', 'DocAssign', 'DocExec', 'DocAssert', 'DocPara', 'DocIf', 'DocWhile', 'PageBreakIfNotEmpty', ) class TraceInfo: "Holder for info about where an object originated" def __init__(self): self.srcFile = '(unknown)' self.startLineNo = -1 self.startLinePos = -1 self.endLineNo = -1 self.endLinePos = -1 ############################################################# # Flowable Objects - a base class and a few examples. # One is just a box to get some metrics. We also have # a paragraph, an image and a special 'page break' # object which fills the space. ############################################################# class Flowable: """Abstract base class for things to be drawn. Key concepts: 1. It knows its size 2. It draws in its own coordinate system (this requires the base API to provide a translate() function. """ _fixedWidth = 0 #assume wrap results depend on arguments? _fixedHeight = 0 def __init__(self): self.width = 0 self.height = 0 self.wrapped = 0 #these are hints to packers/frames as to how the floable should be positioned self.hAlign = 'LEFT' #CENTER/CENTRE or RIGHT self.vAlign = 'BOTTOM' #MIDDLE or TOP #optional holder for trace info self._traceInfo = None self._showBoundary = None #many flowables handle text and must be processed in the #absence of a canvas. tagging them with their encoding #helps us to get conversions right. Use Python codec names. self.encoding = None def _drawOn(self,canv): '''ensure canv is set on and then draw''' self.canv = canv self.draw()#this is the bit you overload del self.canv def _hAlignAdjust(self,x,sW=0): if sW and hasattr(self,'hAlign'): a = self.hAlign if a in ('CENTER','CENTRE', TA_CENTER): x += 0.5*sW elif a in ('RIGHT',TA_RIGHT): x += sW elif a not in ('LEFT',TA_LEFT): raise ValueError("Bad hAlign value "+str(a)) return x def drawOn(self, canvas, x, y, _sW=0): "Tell it to draw itself on the canvas. Do not override" x = self._hAlignAdjust(x,_sW) canvas.saveState() canvas.translate(x, y) self._drawOn(canvas) if hasattr(self, '_showBoundary') and self._showBoundary: #diagnostic tool support canvas.setStrokeColor(gray) canvas.rect(0,0,self.width, self.height) canvas.restoreState() def wrapOn(self, canv, aW, aH): '''intended for use by packers allows setting the canvas on during the actual wrap''' self.canv = canv w, h = self.wrap(aW,aH) del self.canv return w, h def wrap(self, availWidth, availHeight): """This will be called by the enclosing frame before objects are asked their size, drawn or whatever. It returns the size actually used.""" return (self.width, self.height) def minWidth(self): """This should return the minimum required width""" return getattr(self,'_minWidth',self.width) def splitOn(self, canv, aW, aH): '''intended for use by packers allows setting the canvas on during the actual split''' self.canv = canv S = self.split(aW,aH) del self.canv return S def split(self, availWidth, availheight): """This will be called by more sophisticated frames when wrap fails. Stupid flowables should return []. Clever flowables should split themselves and return a list of flowables. If they decide that nothing useful can be fitted in the available space (e.g. if you have a table and not enough space for the first row), also return []""" return [] def getKeepWithNext(self): """returns boolean determining whether the next flowable should stay with this one""" if hasattr(self,'keepWithNext'): return self.keepWithNext elif hasattr(self,'style') and hasattr(self.style,'keepWithNext'): return self.style.keepWithNext else: return 0 def getSpaceAfter(self): """returns how much space should follow this item if another item follows on the same page.""" if hasattr(self,'spaceAfter'): return self.spaceAfter elif hasattr(self,'style') and hasattr(self.style,'spaceAfter'): return self.style.spaceAfter else: return 0 def getSpaceBefore(self): """returns how much space should precede this item if another item precedess on the same page.""" if hasattr(self,'spaceBefore'): return self.spaceBefore elif hasattr(self,'style') and hasattr(self.style,'spaceBefore'): return self.style.spaceBefore else: return 0 def isIndexing(self): """Hook for IndexingFlowables - things which have cross references""" return 0 def identity(self, maxLen=None): ''' This method should attempt to return a string that can be used to identify a particular flowable uniquely. The result can then be used for debugging and or error printouts ''' if hasattr(self, 'getPlainText'): r = self.getPlainText(identify=1) elif hasattr(self, 'text'): r = str(self.text) else: r = '...' if r and maxLen: r = r[:maxLen] return "<%s at %s%s>%s" % (self.__class__.__name__, hex(id(self)), self._frameName(), r) def _doctemplateAttr(self,a): return getattr(getattr(getattr(self,'canv',None),'_doctemplate',None),a,None) def _frameName(self): f = getattr(self,'_frame',None) if not f: f = self._doctemplateAttr('frame') if f and f.id: return ' frame=%s' % f.id return '' class XBox(Flowable): """Example flowable - a box with an x through it and a caption. This has a known size, so does not need to respond to wrap().""" def __init__(self, width, height, text = 'A Box'): Flowable.__init__(self) self.width = width self.height = height self.text = text def __repr__(self): return "XBox(w=%s, h=%s, t=%s)" % (self.width, self.height, self.text) def draw(self): self.canv.rect(0, 0, self.width, self.height) self.canv.line(0, 0, self.width, self.height) self.canv.line(0, self.height, self.width, 0) #centre the text self.canv.setFont(_baseFontName,12) self.canv.drawCentredString(0.5*self.width, 0.5*self.height, self.text) def _trimEmptyLines(lines): #don't want the first or last to be empty while len(lines) and lines[0].strip() == '': lines = lines[1:] while len(lines) and lines[-1].strip() == '': lines = lines[:-1] return lines def _dedenter(text,dedent=0): ''' tidy up text - carefully, it is probably code. If people want to indent code within a source script, you can supply an arg to dedent and it will chop off that many character, otherwise it leaves left edge intact. ''' lines = text.split('\n') if dedent>0: templines = _trimEmptyLines(lines) lines = [] for line in templines: line = line[dedent:].rstrip() lines.append(line) else: lines = _trimEmptyLines(lines) return lines SPLIT_CHARS = "[{( ,.;:/\\-" def splitLines(lines, maximum_length, split_characters, new_line_characters): if split_characters is None: split_characters = SPLIT_CHARS if new_line_characters is None: new_line_characters = "" # Return a table of lines lines_splitted = [] for line in lines: if len(line) > maximum_length: splitLine(line, lines_splitted, maximum_length, \ split_characters, new_line_characters) else: lines_splitted.append(line) return lines_splitted def splitLine(line_to_split, lines_splitted, maximum_length, \ split_characters, new_line_characters): # Used to implement the characters added #at the beginning of each new line created first_line = True # Check if the text can be splitted while line_to_split and len(line_to_split)>0: # Index of the character where we can split split_index = 0 # Check if the line length still exceeds the maximum length if len(line_to_split) <= maximum_length: # Return the remaining of the line split_index = len(line_to_split) else: # Iterate for each character of the line for line_index in range(maximum_length): # Check if the character is in the list # of allowed characters to split on if line_to_split[line_index] in split_characters: split_index = line_index + 1 # If the end of the line was reached # with no character to split on if split_index==0: split_index = line_index + 1 if first_line: lines_splitted.append(line_to_split[0:split_index]) first_line = False maximum_length -= len(new_line_characters) else: lines_splitted.append(new_line_characters + \ line_to_split[0:split_index]) # Remaining text to split line_to_split = line_to_split[split_index:] class Preformatted(Flowable): """This is like the HTML
 tag.
    It attempts to display text exactly as you typed it in a fixed width "typewriter" font.
    By default the line breaks are exactly where you put them, and it will not be wrapped.
    You can optionally define a maximum line length and the code will be wrapped; and 
    extra characters to be inserted at the beginning of each wrapped line (e.g. '> ').
    """
    def __init__(self, text, style, bulletText = None, dedent=0, maxLineLength=None, splitChars=None, newLineChars=""):
        """text is the text to display. If dedent is set then common leading space
        will be chopped off the front (for example if the entire text is indented
        6 spaces or more then each line will have 6 spaces removed from the front).
        """
        self.style = style
        self.bulletText = bulletText
        self.lines = _dedenter(text,dedent)
        if text and maxLineLength:
            self.lines = splitLines(
                                self.lines, 
                                maxLineLength, 
                                splitChars, 
                                newLineChars
                        )

    def __repr__(self):
        bT = self.bulletText
        H = "Preformatted("
        if bT is not None:
            H = "Preformatted(bulletText=%s," % repr(bT)
        return "%s'''\\ \n%s''')" % (H, '\n'.join(self.lines))

    def wrap(self, availWidth, availHeight):
        self.width = availWidth
        self.height = self.style.leading*len(self.lines)
        return (self.width, self.height)

    def minWidth(self):
        style = self.style
        fontSize = style.fontSize
        fontName = style.fontName
        return max([stringWidth(line,fontName,fontSize) for line in self.lines])

    def split(self, availWidth, availHeight):
        #returns two Preformatted objects

        #not sure why they can be called with a negative height
        if availHeight < self.style.leading:
            return []

        linesThatFit = int(availHeight * 1.0 / self.style.leading)

        text1 = '\n'.join(self.lines[0:linesThatFit])
        text2 = '\n'.join(self.lines[linesThatFit:])
        style = self.style
        if style.firstLineIndent != 0:
            style = deepcopy(style)
            style.firstLineIndent = 0
        return [Preformatted(text1, self.style), Preformatted(text2, style)]

    def draw(self):
        #call another method for historical reasons.  Besides, I
        #suspect I will be playing with alternate drawing routines
        #so not doing it here makes it easier to switch.

        cur_x = self.style.leftIndent
        cur_y = self.height - self.style.fontSize
        self.canv.addLiteral('%PreformattedPara')
        if self.style.textColor:
            self.canv.setFillColor(self.style.textColor)
        tx = self.canv.beginText(cur_x, cur_y)
        #set up the font etc.
        tx.setFont( self.style.fontName,
                    self.style.fontSize,
                    self.style.leading)

        for text in self.lines:
            tx.textLine(text)
        self.canv.drawText(tx)

class Image(Flowable):
    """an image (digital picture).  Formats supported by PIL/Java 1.4 (the Python/Java Imaging Library
       are supported.  At the present time images as flowables are always centered horozontally
       in the frame. We allow for two kinds of lazyness to allow for many images in a document
       which could lead to file handle starvation.
       lazy=1 don't open image until required.
       lazy=2 open image when required then shut it.
    """
    _fixedWidth = 1
    _fixedHeight = 1
    def __init__(self, filename, width=None, height=None, kind='direct', mask="auto", lazy=1):
        """If size to draw at not specified, get it from the image."""
        self.hAlign = 'CENTER'
        self._mask = mask
        fp = hasattr(filename,'read')
        if fp:
            self._file = filename
            self.filename = repr(filename)
        else:
            self._file = self.filename = filename
        if not fp and os.path.splitext(filename)[1] in ['.jpg', '.JPG', '.jpeg', '.JPEG']:
            # if it is a JPEG, will be inlined within the file -
            # but we still need to know its size now
            from reportlab.lib.utils import open_for_read
            f = open_for_read(filename, 'b')
            try:
                try:
                    info = pdfutils.readJPEGInfo(f)
                except:
                    #couldn't read as a JPEG, try like normal
                    self._setup(width,height,kind,lazy)
                    return
            finally:
                f.close()
            self.imageWidth = info[0]
            self.imageHeight = info[1]
            self._img = None
            self._setup(width,height,kind,0)
        elif fp:
            self._setup(width,height,kind,0)
        else:
            self._setup(width,height,kind,lazy)

    def _setup(self,width,height,kind,lazy):
        self._lazy = lazy
        self._width = width
        self._height = height
        self._kind = kind
        if lazy<=0: self._setup_inner()

    def _setup_inner(self):
        width = self._width
        height = self._height
        kind = self._kind
        img = self._img
        if img: self.imageWidth, self.imageHeight = img.getSize()
        if self._lazy>=2: del self._img
        if kind in ['direct','absolute']:
            self.drawWidth = width or self.imageWidth
            self.drawHeight = height or self.imageHeight
        elif kind in ['percentage','%']:
            self.drawWidth = self.imageWidth*width*0.01
            self.drawHeight = self.imageHeight*height*0.01
        elif kind in ['bound','proportional']:
            factor = min(float(width)/self.imageWidth,float(height)/self.imageHeight)
            self.drawWidth = self.imageWidth*factor
            self.drawHeight = self.imageHeight*factor

    def _restrictSize(self,aW,aH):
        if self.drawWidth>aW+_FUZZ or self.drawHeight>aH+_FUZZ:
            self._oldDrawSize = self.drawWidth, self.drawHeight
            factor = min(float(aW)/self.drawWidth,float(aH)/self.drawHeight)
            self.drawWidth *= factor
            self.drawHeight *= factor
        return self.drawWidth, self.drawHeight

    def _unRestrictSize(self):
        dwh = getattr(self,'_oldDrawSize',None)
        if dwh:
            self.drawWidth, self.drawHeight = dwh

    def __getattr__(self,a):
        if a=='_img':
            from reportlab.lib.utils import ImageReader  #this may raise an error
            self._img = ImageReader(self._file)
            if not isinstance(self._file,strTypes):
                self._file = None
                if self._lazy>=2: self._lazy = 1    #here we're assuming we cannot read again
            return self._img
        elif a in ('drawWidth','drawHeight','imageWidth','imageHeight'):
            self._setup_inner()
            return self.__dict__[a]
        raise AttributeError(".%s" % (id(self),a))

    def wrap(self, availWidth, availHeight):
        #the caller may decide it does not fit.
        return self.drawWidth, self.drawHeight

    def draw(self):
        lazy = self._lazy
        if lazy>=2: self._lazy = 1
        self.canv.drawImage(    self._img or self.filename,
                                getattr(self,'_offs_x',0),
                                getattr(self,'_offs_y',0),
                                self.drawWidth,
                                self.drawHeight,
                                mask=self._mask,
                                )
        if lazy>=2:
            self._img = self._file = None
            self._lazy = lazy

    def identity(self,maxLen=None):
        r = Flowable.identity(self,maxLen)
        if r[-4:]=='>...' and isinstance(self.filename,str):
            r = "%s filename=%s>" % (r[:-4],self.filename)
        return r

class NullDraw(Flowable):
    def draw(self):
        pass

class Spacer(NullDraw):
    """A spacer just takes up space and doesn't draw anything - it guarantees
       a gap between objects."""
    _fixedWidth = 1
    _fixedHeight = 1
    def __init__(self, width, height, isGlue=False):
        self.width = width
        if isGlue:
            self.height = 1e-4
            self.spacebefore = height
        self.height = height

    def __repr__(self):
        return "%s(%s, %s)" % (self.__class__.__name__,self.width, self.height)

class UseUpSpace(NullDraw):
    def __init__(self):
        pass

    def __repr__(self):
        return "%s()" % self.__class__.__name__

    def wrap(self, availWidth, availHeight):
        self.width = availWidth
        self.height = availHeight
        return (availWidth,availHeight-1e-8)  #step back a point

class PageBreak(UseUpSpace):
    """Move on to the next page in the document.
       This works by consuming all remaining space in the frame!"""
    def __init__(self,nextTemplate=None):
        self.nextTemplate = nextTemplate

class SlowPageBreak(PageBreak):
    pass

class PageBreakIfNotEmpty(PageBreak):
    pass

class CondPageBreak(Spacer):
    """use up a frame if not enough vertical space effectively CondFrameBreak"""
    def __init__(self, height):
        self.height = height

    def __repr__(self):
        return "CondPageBreak(%s)" %(self.height,)

    def wrap(self, availWidth, availHeight):
        if availHeightaH and (not self._maxHeight or aH>self._maxHeight)
        C1 = (self._H0>aH) or C0 and atTop
        if C0 or C1:
            if C0:
                from reportlab.platypus.doctemplate import FrameBreak
                A = FrameBreak
            else:
                from reportlab.platypus.doctemplate import NullActionFlowable
                A = NullActionFlowable
            S.insert(0,A())
        return S

    def identity(self, maxLen=None):
        msg = "<%s at %s%s> containing :%s" % (self.__class__.__name__,hex(id(self)),self._frameName(),"\n".join([f.identity() for f in self._content]))
        if maxLen:
            return msg[0:maxLen]
        else:
            return msg

class Macro(Flowable):
    """This is not actually drawn (i.e. it has zero height)
    but is executed when it would fit in the frame.  Allows direct
    access to the canvas through the object 'canvas'"""
    def __init__(self, command):
        self.command = command
    def __repr__(self):
        return "Macro(%s)" % repr(self.command)
    def wrap(self, availWidth, availHeight):
        return (0,0)
    def draw(self):
        exec(self.command, globals(), {'canvas':self.canv})

def _nullCallable(*args,**kwds):
    pass

class CallerMacro(Flowable):
    '''
    like Macro, but with callable command(s)
    drawCallable(self)
    wrapCallable(self,aW,aH)
    '''
    def __init__(self, drawCallable=None, wrapCallable=None):
        self._drawCallable = drawCallable or _nullCallable
        self._wrapCallable = wrapCallable or _nullCallable
    def __repr__(self):
        return "CallerMacro(%r,%r)" % (self._drawCallable,self._wrapCallable)
    def wrap(self, aW, aH):
        self._wrapCallable(self,aW,aH)
        return (0,0)
    def draw(self):
        self._drawCallable(self)

class ParagraphAndImage(Flowable):
    '''combine a Paragraph and an Image'''
    def __init__(self,P,I,xpad=3,ypad=3,side='right'):
        self.P = P
        self.I = I
        self.xpad = xpad
        self.ypad = ypad
        self._side = side

    def getSpaceBefore(self):
        return max(self.P.getSpaceBefore(),self.I.getSpaceBefore())

    def getSpaceAfter(self):
        return max(self.P.getSpaceAfter(),self.I.getSpaceAfter())

    def wrap(self,availWidth,availHeight):
        wI, hI = self.I.wrap(availWidth,availHeight)
        self.wI = wI
        self.hI = hI
        # work out widths array for breaking
        self.width = availWidth
        P = self.P
        style = P.style
        xpad = self.xpad
        ypad = self.ypad
        leading = style.leading
        leftIndent = style.leftIndent
        later_widths = availWidth - leftIndent - style.rightIndent
        intermediate_widths = later_widths - xpad - wI
        first_line_width = intermediate_widths - style.firstLineIndent
        P.width = 0
        nIW = int((hI+ypad)/(leading*1.0))
        P.blPara = P.breakLines([first_line_width] + nIW*[intermediate_widths]+[later_widths])
        if self._side=='left':
            self._offsets = [wI+xpad]*(1+nIW)+[0]
        P.height = len(P.blPara.lines)*leading
        self.height = max(hI,P.height)
        return (self.width, self.height)

    def split(self,availWidth, availHeight):
        P, wI, hI, ypad = self.P, self.wI, self.hI, self.ypad
        if hI+ypad>availHeight or len(P.frags)<=0: return []
        S = P.split(availWidth,availHeight)
        if not S: return S
        P = self.P = S[0]
        del S[0]
        style = P.style
        P.height = len(self.P.blPara.lines)*style.leading
        self.height = max(hI,P.height)
        return [self]+S

    def draw(self):
        canv = self.canv
        if self._side=='left':
            self.I.drawOn(canv,0,self.height-self.hI)
            self.P._offsets = self._offsets
            try:
                self.P.drawOn(canv,0,0)
            finally:
                del self.P._offsets
        else:
            self.I.drawOn(canv,self.width-self.wI-self.xpad,self.height-self.hI)
            self.P.drawOn(canv,0,0)

class FailOnWrap(NullDraw):
    def wrap(self, availWidth, availHeight):
        raise ValueError("FailOnWrap flowable wrapped and failing as ordered!")

class FailOnDraw(Flowable):
    def wrap(self, availWidth, availHeight):
        return 0,0

    def draw(self):
        raise ValueError("FailOnDraw flowable drawn, and failing as ordered!")

class HRFlowable(Flowable):
    '''Like the hr tag'''
    def __init__(self,
            width="80%",
            thickness=1,
            lineCap='round',
            color=lightgrey,
            spaceBefore=1, spaceAfter=1,
            hAlign='CENTER', vAlign='BOTTOM',
            dash=None):
        Flowable.__init__(self)
        self.width = width
        self.lineWidth = thickness
        self.lineCap=lineCap
        self.spaceBefore = spaceBefore
        self.spaceAfter = spaceAfter
        self.color = color
        self.hAlign = hAlign
        self.vAlign = vAlign
        self.dash = dash

    def __repr__(self):
        return "HRFlowable(width=%s, height=%s)" % (self.width, self.height)

    def wrap(self, availWidth, availHeight):
        w = self.width
        if type(w) is type(''):
            w = w.strip()
            if w.endswith('%'): w = availWidth*float(w[:-1])*0.01
            else: w = float(w)
        w = min(w,availWidth)
        self._width = w
        return w, self.lineWidth

    def draw(self):
        canv = self.canv
        canv.saveState()
        canv.setLineWidth(self.lineWidth)
        canv.setLineCap({'butt':0,'round':1, 'square': 2}[self.lineCap.lower()])
        canv.setStrokeColor(self.color)
        if self.dash: canv.setDash(self.dash)
        canv.line(0, 0, self._width, self.height)
        canv.restoreState()

class _PTOInfo:
    def __init__(self,trailer,header):
        self.trailer = _flowableSublist(trailer)
        self.header = _flowableSublist(header)

def cdeepcopy(obj):
    if hasattr(obj,'deepcopy'):
        return obj.deepcopy()
    else:
        return deepcopy(obj)

class _Container(_ContainerSpace):  #Abstract some common container like behaviour
    def drawOn(self, canv, x, y, _sW=0, scale=1.0, content=None, aW=None):
        '''we simulate being added to a frame'''
        from reportlab.platypus.doctemplate import ActionFlowable, Indenter
        x0 = x
        y0 = y
        pS = 0
        if aW is None: aW = self.width
        aW *= scale
        if content is None:
            content = self._content
        x = self._hAlignAdjust(x,_sW*scale)
        y += self.height*scale
        yt = y
        frame = getattr(self,'_frame',None)
        for c in content:
            if not ignoreContainerActions and isinstance(c,ActionFlowable):
                c.apply(self.canv._doctemplate)
                continue
            if isinstance(c,Indenter):
                x += c.left*scale
                aW -= (c.left+c.right)*scale
                continue
            w, h = c.wrapOn(canv,aW,0xfffffff)
            if (w<_FUZZ or h<_FUZZ) and not getattr(c,'_ZEROSIZE',None): continue
            if yt!=y:
                s = c.getSpaceBefore()
                if not getattr(c,'_SPACETRANSFER',False):
                    h += max(s-pS,0)
            y -= h
            fbg = getattr(frame,'_frameBGs',None)
            s = c.getSpaceAfter()
            if getattr(c,'_SPACETRANSFER',False):
                s = pS
            pS = s
            if fbg:
                fbgl, fbgr, fbgc = fbg[-1]
                fbw = scale*(frame._width-fbgl-fbgr)
                fbh = y + h + pS
                fby = max(y0,y-pS)
                fbh = max(0,fbh-fby)
                if abs(fbw)>_FUZZ and abs(fbh)>_FUZZ:
                    canv.saveState()
                    canv.setFillColor(fbgc)
                    canv.rect(x0+scale*(fbgl-frame._leftPadding)-0.1,fby-0.1,fbw+0.2,fbh+0.2,stroke=0,fill=1)
                    canv.restoreState()
            c._frame = frame
            c.drawOn(canv,x,y,_sW=aW-w)
            if c is not content[-1] and not getattr(c,'_SPACETRANSFER',None):
                y -= pS
            del c._frame

    def copyContent(self,content=None):
        C = [].append
        for c in (content or self._content):
            C(cdeepcopy(c))
        self._content = C.__self__

class PTOContainer(_Container,Flowable):
    '''PTOContainer(contentList,trailerList,headerList)

    A container for flowables decorated with trailer & header lists.
    If the split operation would be called then the trailer and header
    lists are injected before and after the split. This allows specialist
    "please turn over" and "continued from previous" like behaviours.'''
    def __init__(self,content,trailer=None,header=None):
        I = _PTOInfo(trailer,header)
        self._content = C = []
        for _ in _flowableSublist(content):
            if isinstance(_,PTOContainer):
                C.extend(_._content)
            else:
                C.append(_)
                if not hasattr(_,'_ptoinfo'): _._ptoinfo = I

    def wrap(self,availWidth,availHeight):
        self.width, self.height = _listWrapOn(self._content,availWidth,self.canv)
        return self.width,self.height

    def split(self, availWidth, availHeight):
        from reportlab.platypus.doctemplate import Indenter
        if availHeight<0: return []
        canv = self.canv
        C = self._content
        x = i = H = pS = hx = 0
        n = len(C)
        I2W = {}
        dLeft = dRight = 0
        for x in xrange(n):
            c = C[x]
            I = c._ptoinfo
            if I not in I2W.keys():
                T = I.trailer
                Hdr = I.header
                tW, tH = _listWrapOn(T, availWidth, self.canv)
                if len(T):  #trailer may have no content
                    tSB = T[0].getSpaceBefore()
                else:
                    tSB = 0
                I2W[I] = T,tW,tH,tSB
            else:
                T,tW,tH,tSB = I2W[I]
            _, h = c.wrapOn(canv,availWidth,0xfffffff)
            if isinstance(c,Indenter):
                dw = c.left+c.right
                dLeft += c.left
                dRight += c.right
                availWidth -= dw
                pS = 0
                hx = 0
            else:
                if x:
                    hx = max(c.getSpaceBefore()-pS,0)
                    h += hx
                pS = c.getSpaceAfter()
            H += h+pS
            tHS = tH+max(tSB,pS)
            if H+tHS>=availHeight-_FUZZ: break
            i += 1

        #first retract last thing we tried
        H -= (h+pS)

        #attempt a sub split on the last one we have
        aH = (availHeight-H-tHS-hx)*0.99999
        if aH>=0.05*availHeight:
            SS = c.splitOn(canv,availWidth,aH)
        else:
            SS = []

        if abs(dLeft)+abs(dRight)>1e-8:
            R1I = [Indenter(-dLeft,-dRight)]
            R2I = [Indenter(dLeft,dRight)]
        else:
            R1I = R2I = []

        if not SS:
            j = i
            while i>1 and C[i-1].getKeepWithNext():
                i -= 1
                C[i].keepWithNext = 0

            if i==1 and C[0].getKeepWithNext():
                #robin's black sheep
                i = j
                C[0].keepWithNext = 0

        F = [UseUpSpace()]

        if len(SS)>1:
            R1 = C[:i]+SS[:1]+R1I+T+F
            R2 = Hdr+R2I+SS[1:]+C[i+1:]
        elif not i:
            return []
        else:
            R1 = C[:i]+R1I+T+F
            R2 = Hdr+R2I+C[i:]
        T =  R1 + [PTOContainer(R2,[copy(x) for x in I.trailer],[copy(x) for x in I.header])]
        return T

#utility functions used by KeepInFrame
def _hmodel(s0,s1,h0,h1):
    # calculate the parameters in the model
    # h = a/s**2 + b/s
    a11 = 1./s0**2
    a12 = 1./s0
    a21 = 1./s1**2
    a22 = 1./s1
    det = a11*a22-a12*a21
    b11 = a22/det
    b12 = -a12/det
    b21 = -a21/det
    b22 = a11/det
    a = b11*h0+b12*h1
    b = b21*h0+b22*h1
    return a,b

def _qsolve(h,ab):
    '''solve the model v = a/s**2 + b/s for an s which gives us v==h'''
    a,b = ab
    if abs(a)<=_FUZZ:
        return b/h
    t = 0.5*b/a
    from math import sqrt
    f = -h/a
    r = t*t-f
    if r<0: return None
    r = sqrt(r)
    if t>=0:
        s1 = -t - r
    else:
        s1 = -t + r
    s2 = f/s1
    return max(1./s1, 1./s2)

class KeepInFrame(_Container,Flowable):
    def __init__(self, maxWidth, maxHeight, content=[], mergeSpace=1, mode='shrink', name='',hAlign='LEFT',vAlign='BOTTOM', fakeWidth=None):
        '''mode describes the action to take when overflowing
            error       raise an error in the normal way
            continue    ignore ie just draw it and report maxWidth, maxHeight
            shrink      shrinkToFit
            truncate    fit as much as possible
            set fakeWidth to False to make _listWrapOn do the 'right' thing
        '''
        self.name = name
        self.maxWidth = maxWidth
        self.maxHeight = maxHeight
        self.mode = mode
        assert mode in ('error','overflow','shrink','truncate'), '%s invalid mode value %s' % (self.identity(),mode)
        assert maxHeight>=0,  '%s invalid maxHeight value %s' % (self.identity(),maxHeight)
        if mergeSpace is None: mergeSpace = overlapAttachedSpace
        self.mergespace = mergeSpace
        self._content = content or []
        self.vAlign = vAlign
        self.hAlign = hAlign
        self.fakeWidth = fakeWidth

    def _getAvailableWidth(self):
        return self.maxWidth - self._leftExtraIndent - self._rightExtraIndent

    def identity(self, maxLen=None):
        return "<%s at %s%s%s> size=%sx%s" % (self.__class__.__name__, hex(id(self)), self._frameName(),
                getattr(self,'name','') and (' name="%s"'% getattr(self,'name','')) or '',
                getattr(self,'maxWidth','') and (' maxWidth=%s'%fp_str(getattr(self,'maxWidth',0))) or '',
                getattr(self,'maxHeight','')and (' maxHeight=%s' % fp_str(getattr(self,'maxHeight')))or '')

    def wrap(self,availWidth,availHeight):
        from reportlab.platypus.doctemplate import LayoutError
        mode = self.mode
        maxWidth = float(min(self.maxWidth or availWidth,availWidth))
        maxHeight = float(min(self.maxHeight or availHeight,availHeight))
        fakeWidth = self.fakeWidth
        W, H = _listWrapOn(self._content,maxWidth,self.canv, fakeWidth=fakeWidth)
        if (mode=='error' and (W>maxWidth+_FUZZ or H>maxHeight+_FUZZ)):
            ident = 'content %sx%s too large for %s' % (W,H,self.identity(30))
            #leave to keep apart from the raise
            raise LayoutError(ident)
        elif W<=maxWidth+_FUZZ and H<=maxHeight+_FUZZ:
            self.width = W-_FUZZ      #we take what we get
            self.height = H-_FUZZ
        elif mode in ('overflow','truncate'):   #we lie
            self.width = min(maxWidth,W)-_FUZZ
            self.height = min(maxHeight,H)-_FUZZ
        else:
            def func(x):
                x = float(x)
                W, H = _listWrapOn(self._content,x*maxWidth,self.canv, fakeWidth=fakeWidth)
                W /= x
                H /= x
                return W, H
            W0 = W
            H0 = H
            s0 = 1
            if W>maxWidth+_FUZZ:
                #squeeze out the excess width and or Height
                s1 = W/maxWidth     #linear model
                W, H = func(s1)
                if H<=maxHeight+_FUZZ:
                    self.width = W-_FUZZ
                    self.height = H-_FUZZ
                    self._scale = s1
                    return W,H
                s0 = s1
                H0 = H
                W0 = W
            s1 = H/maxHeight
            W, H = func(s1)
            self.width = W-_FUZZ
            self.height = H-_FUZZ
            self._scale = s1
            if H=maxHeight+_FUZZ:
                #the standard case W should be OK, H is short we want
                #to find the smallest s with H<=maxHeight
                H1 = H
                for f in 0, 0.01, 0.05, 0.10, 0.15:
                    #apply the quadratic model
                    s = _qsolve(maxHeight*(1-f),_hmodel(s0,s1,H0,H1))
                    W, H = func(s)
                    if H<=maxHeight+_FUZZ and W<=maxWidth+_FUZZ:
                        self.width = W-_FUZZ
                        self.height = H-_FUZZ
                        self._scale = s
                        break

        return self.width, self.height

    def drawOn(self, canv, x, y, _sW=0):
        scale = getattr(self,'_scale',1.0)
        truncate = self.mode=='truncate'
        ss = scale!=1.0 or truncate
        if ss:
            canv.saveState()
            if truncate:
                p = canv.beginPath()
                p.rect(x, y, self.width,self.height)
                canv.clipPath(p,stroke=0)
            else:
                canv.translate(x,y)
                x=y=0
                canv.scale(1.0/scale, 1.0/scale)
        _Container.drawOn(self, canv, x, y, _sW=_sW, scale=scale)
        if ss: canv.restoreState()

class ImageAndFlowables(_Container,Flowable):
    '''combine a list of flowables and an Image'''
    def __init__(self,I,F,imageLeftPadding=0,imageRightPadding=3,imageTopPadding=0,imageBottomPadding=3,
                    imageSide='right', imageHref=None):
        self._content = _flowableSublist(F)
        self._I = I
        self._irpad = imageRightPadding
        self._ilpad = imageLeftPadding
        self._ibpad = imageBottomPadding
        self._itpad = imageTopPadding
        self._side = imageSide
        self.imageHref = imageHref

    def deepcopy(self):
        c = copy(self)  #shallow
        self._reset()
        c.copyContent() #partially deep?
        return c

    def getSpaceAfter(self):
        if hasattr(self,'_C1'):
            C = self._C1
        elif hasattr(self,'_C0'):
            C = self._C0
        else:
            C = self._content
        return _Container.getSpaceAfter(self,C)

    def getSpaceBefore(self):
        return max(self._I.getSpaceBefore(),_Container.getSpaceBefore(self))

    def _reset(self):
        for a in ('_wrapArgs','_C0','_C1'):
            try:
                delattr(self,a)
            except:
                pass

    def wrap(self,availWidth,availHeight):
        canv = self.canv
        I = self._I
        if hasattr(self,'_wrapArgs'):
            if self._wrapArgs==(availWidth,availHeight) and getattr(I,'_oldDrawSize',None) is None:
                return self.width,self.height
            self._reset()
            I._unRestrictSize()
        self._wrapArgs = availWidth, availHeight
        I.wrap(availWidth,availHeight)
        wI, hI = I._restrictSize(availWidth,availHeight)
        self._wI = wI
        self._hI = hI
        ilpad = self._ilpad
        irpad = self._irpad
        ibpad = self._ibpad
        itpad = self._itpad
        self._iW = iW = availWidth - irpad - wI - ilpad
        aH = itpad + hI + ibpad
        if iW>_FUZZ:
            W,H0,self._C0,self._C1 = self._findSplit(canv,iW,aH)
        else:
            W = availWidth
            H0 = 0
        if W>iW+_FUZZ:
            self._C0 = []
            self._C1 = self._content
        aH = self._aH = max(aH,H0)
        self.width = availWidth
        if not self._C1:
            self.height = aH
        else:
            W1,H1 = _listWrapOn(self._C1,availWidth,canv)
            self.height = aH+H1
        return self.width, self.height

    def split(self,availWidth, availHeight):
        if hasattr(self,'_wrapArgs'):
            I = self._I
            if self._wrapArgs!=(availWidth,availHeight) or getattr(I,'_oldDrawSize',None) is not None:
                self._reset()
                I._unRestrictSize()
        W,H=self.wrap(availWidth,availHeight)
        if self._aH>availHeight: return []
        C1 = self._C1
        if C1:
            S = C1[0].split(availWidth,availHeight-self._aH)
            if not S:
                _C1 = []
            else:
                _C1 = [S[0]]
                C1 = S[1:]+C1[1:]
        else:
            _C1 = []
        return [ImageAndFlowables(
                    self._I,
                    self._C0+_C1,
                    imageLeftPadding=self._ilpad,
                    imageRightPadding=self._irpad,
                    imageTopPadding=self._itpad,
                    imageBottomPadding=self._ibpad,
                    imageSide=self._side, imageHref=self.imageHref)
                    ]+C1

    def drawOn(self, canv, x, y, _sW=0):
        if self._side=='left':
            Ix = x + self._ilpad
            Fx = Ix+ self._irpad + self._wI
        else:
            Ix = x + self.width-self._wI-self._irpad
            Fx = x
        self._I.drawOn(canv,Ix,y+self.height-self._itpad-self._hI)

        if self.imageHref:
            canv.linkURL(self.imageHref, (Ix, y+self.height-self._itpad-self._hI, Ix + self._wI, y+self.height), relative=1)

        if self._C0:
            _Container.drawOn(self, canv, Fx, y, content=self._C0, aW=self._iW)
        if self._C1:
            aW, aH = self._wrapArgs
            _Container.drawOn(self, canv, x, y-self._aH,content=self._C1, aW=aW)

    def _findSplit(self,canv,availWidth,availHeight,mergeSpace=1,obj=None):
        '''return max width, required height for a list of flowables F'''
        W = 0
        H = 0
        pS = sB = 0
        atTop = 1
        F = self._content
        for i,f in enumerate(F):
            w,h = f.wrapOn(canv,availWidth,0xfffffff)
            if w<=_FUZZ or h<=_FUZZ: continue
            W = max(W,w)
            if not atTop:
                s = f.getSpaceBefore()
                if mergeSpace: s = max(s-pS,0)
                H += s
            else:
                if obj is not None: obj._spaceBefore = f.getSpaceBefore()
                atTop = 0
            if H>=availHeight or w>availWidth:
                return W, availHeight, F[:i],F[i:]
            H += h
            if H>availHeight:
                from reportlab.platypus.paragraph import Paragraph
                aH = availHeight-(H-h)
                if isinstance(f,(Paragraph,Preformatted)):
                    leading = f.style.leading
                    nH = leading*int(aH/float(leading))+_FUZZ
                    if nH1:
            S[0] = TopPadder(S[0])
        return S

    def drawOn(self, canvas, x, y, _sW=0):
        self.__f.drawOn(canvas,x,y-max(0,self.__dh-1e-8),_sW)

    def __setattr__(self,a,v):
        setattr(self.__f,a,v)

    def __getattr__(self,a):
        return getattr(self.__f,a)

    def __delattr__(self,a):
        delattr(self.__f,a)

class DocAssign(NullDraw):
    '''At wrap time this flowable evaluates var=expr in the doctemplate namespace'''
    _ZEROSIZE=1
    def __init__(self,var,expr,life='forever'):
        Flowable.__init__(self)
        self.args = var,expr,life

    def funcWrap(self,aW,aH):
        NS=self._doctemplateAttr('_nameSpace')
        NS.update(dict(availableWidth=aW,availableHeight=aH))
        try:
            return self.func()
        finally:
            for k in 'availableWidth','availableHeight':
                try:
                    del NS[k]
                except:
                    pass

    def func(self):
        return self._doctemplateAttr('d'+self.__class__.__name__[1:])(*self.args)

    def wrap(self,aW,aH):
        self.funcWrap(aW,aH)
        return 0,0

class DocExec(DocAssign):
    '''at wrap time exec stmt in doc._nameSpace'''
    def __init__(self,stmt,lifetime='forever'):
        Flowable.__init__(self)
        self.args=stmt,lifetime

class DocPara(DocAssign):
    '''at wrap time create a paragraph with the value of expr as text
    if format is specified it should use %(__expr__)s for string interpolation
    of the expression expr (if any). It may also use %(name)s interpolations
    for other variables in the namespace.
    suitable defaults will be used if style and klass are None
    '''
    def __init__(self,expr,format=None,style=None,klass=None,escape=True):
        Flowable.__init__(self)
        self.expr=expr
        self.format=format
        self.style=style
        self.klass=klass
        self.escape=escape

    def func(self):
        expr = self.expr
        if expr:
            if not isinstance(expr,str): expr = str(expr)
            return self._doctemplateAttr('docEval')(expr)

    def add_content(self,*args):
        self._doctemplateAttr('frame').add_generated_content(*args)

    def get_value(self,aW,aH):
        value = self.funcWrap(aW,aH)
        if self.format:
            NS=self._doctemplateAttr('_nameSpace').copy()
            NS.update(dict(availableWidth=aW,availableHeight=aH))
            NS['__expr__'] = value
            value = self.format % NS
        else:
            value = str(value)
        return value

    def wrap(self,aW,aH):
        value = self.get_value(aW,aH)
        P = self.klass
        if not P:
            from reportlab.platypus.paragraph import Paragraph as P
        style = self.style
        if not style:
            from reportlab.lib.styles import getSampleStyleSheet
            style=getSampleStyleSheet()['Code']
        if self.escape:
            from xml.sax.saxutils import escape
            value=escape(value)
        self.add_content(P(value,style=style))
        return 0,0

class DocAssert(DocPara):
    def __init__(self,cond,format=None):
        Flowable.__init__(self)
        self.expr=cond
        self.format=format

    def funcWrap(self,aW,aH):
        self._cond = DocPara.funcWrap(self,aW,aH)
        return self._cond

    def wrap(self,aW,aH):
        value = self.get_value(aW,aH)
        if not bool(self._cond):
            raise AssertionError(value)
        return 0,0

class DocIf(DocPara):
    def __init__(self,cond,thenBlock,elseBlock=[]):
        Flowable.__init__(self)
        self.expr = cond
        self.blocks = elseBlock or [],thenBlock

    def checkBlock(self,block):
        if not isinstance(block,(list,tuple)):
            block = (block,)
        return block

    def wrap(self,aW,aH):
        self.add_content(*self.checkBlock(self.blocks[int(bool(self.funcWrap(aW,aH)))]))
        return 0,0

class DocWhile(DocIf):
    def __init__(self,cond,whileBlock):
        Flowable.__init__(self)
        self.expr = cond
        self.block = self.checkBlock(whileBlock)

    def wrap(self,aW,aH):
        if bool(self.funcWrap(aW,aH)):
            self.add_content(*(list(self.block)+[self]))
        return 0,0