__doc__="""

Image functionality sliced out of canvas.py for generalization

"""

import os

import string

import cStringIO

from types import StringType

from reportlab.pdfbase import pdfutils

from reportlab.lib.utils import fp_str

try:

	import zlib

except ImportError:

	zlib = None

class PDFImage:

    def __init__(self, image, x,y, width=None, height=None):

        self.image = image

        self.point = (x,y)

        self.dimensions = (width, height)

    def jpg_imagedata(self):

        #directly process JPEG files

        #open file, needs some error handling!!

        imageFile = open(self.image, 'rb')

        info = pdfutils.readJPEGInfo(imageFile)

        imgwidth, imgheight = info[0], info[1]

        if info[2] == 1:

            colorSpace = 'DeviceGray'

        elif info[2] == 3:

            colorSpace = 'DeviceRGB'

        else: #maybe should generate an error, is this right for CMYK?

            colorSpace = 'DeviceCMYK'

        imageFile.seek(0) #reset file pointer

        imagedata = []

        #imagedata.append('BI /Width %d /Height /BitsPerComponent 8 /ColorSpace /%s /Filter [/Filter [ /ASCII85Decode /DCTDecode] ID' % (info[0], info[1], colorSpace))

        imagedata.append('BI /W %d /H %d /BPC 8 /CS /%s /F [/A85 /DCT] ID' % (imgwidth, imgheight, colorSpace))

        #write in blocks of (??) 60 characters per line to a list

        compressed = imageFile.read()

        encoded = pdfutils._AsciiBase85Encode(compressed)

        outstream = cStringIO.StringIO(encoded)

        dataline = outstream.read(60)

        while dataline <> "":

            imagedata.append(dataline)

            dataline = outstream.read(60)

        imagedata.append('EI')

        return (imagedata, imgwidth, imgheight)

    def cache_imagedata(self):

        image = self.image

        if not pdfutils.cachedImageExists(image):

            if not zlib:

                print 'zlib not available'

                return

            try:

                import Image

            except ImportError:

                print 'Python Imaging Library not available'

                return

            pdfutils.cacheImageFile(image)

        #now we have one cached, slurp it in

        cachedname = os.path.splitext(image)[0] + '.a85'

        imagedata = open(cachedname,'rb').readlines()

        #trim off newlines...

        imagedata = map(string.strip, imagedata)

        return imagedata

    def PIL_imagedata(self):

        image = self.image

        if not zlib:

            print 'zlib not available'

            return

        myimage = image.convert('RGB')

        imgwidth, imgheight = myimage.size

        # this describes what is in the image itself

        # *NB* according to the spec you can only use the short form in inline images

        #imagedata.append('BI /Width %d /Height /BitsPerComponent 8 /ColorSpace /%s /Filter [/Filter [ /ASCII85Decode /FlateDecode] ID' % (imgwidth, imgheight,'RGB'))

        imagedata.append('BI /W %d /H %d /BPC 8 /CS /RGB /F [/A85 /Fl] ID' % (imgwidth, imgheight))

        #use a flate filter and Ascii Base 85 to compress

        raw = myimage.tostring()

        assert(len(raw) == imgwidth * imgheight, "Wrong amount of data for image")

        compressed = zlib.compress(raw)   #this bit is very fast...

        encoded = pdfutils._AsciiBase85Encode(compressed) #...sadly this isn't

        #write in blocks of (??) 60 characters per line to a list

        outstream = cStringIO.StringIO(encoded)

        dataline = outstream.read(60)

        while dataline <> "":

            imagedata.append(dataline)

            dataline = outstream.read(60)

        imagedata.append('EI')

        return (imagedata, imgwidth, imgheight) 

    def drawInlineImage(self, canvas): #, image, x,y, width=None,height=None):

        """Draw an Image into the specified rectangle.  If width and

        height are omitted, they are calculated from the image size.

        Also allow file names as well as images.  This allows a

        caching mechanism"""

        image = self.image 

        (x,y) = self.point

        (width, height) = self.dimensions

        if type(image) == StringType:

            if os.path.splitext(image)[1] in ['.jpg', '.JPG', '.jpeg', '.JPEG']:

                (imagedata, imgwidth, imgheight) = self.jpg_imagedata()

            else:

                if hasattr(self,'noImageCaching') and canvas.noImageCaching:

                    imagedata = pdfutils.cacheImageFile(image,returnInMemory=1)

                else:

                    imagedata = self.cache_imagedata()

                #parse line two for width, height

                words = string.split(imagedata[1])

                imgwidth = string.atoi(words[1])

                imgheight = string.atoi(words[3])

        else:

            (imagedata, imgwidth, imgheight) = self.PIL_imagedata()

        #now build the PDF for the image.

        if not width:

            width = imgwidth

        if not height:

            height = imgheight

        # this says where and how big to draw it

        if not canvas.bottomup: y = y+height

        canvas._code.append('q %s 0 0 %s cm' % (fp_str(width), fp_str(height, x, y)))

        # self._code.extend(imagedata) if >=python-1.5.2

        for line in imagedata:

            canvas._code.append(line)

        canvas._code.append('Q')