# Source code for fontTools.ttLib.tables.C_B_D_T_

    # Copyright 2013 Google, Inc. All Rights Reserved.
    #
    # Google Author(s): Matt Fontaine

    from fontTools.misc.textTools import bytesjoin
    from fontTools.misc import sstruct
    from . import E_B_D_T_
    from .BitmapGlyphMetrics import BigGlyphMetrics, bigGlyphMetricsFormat, SmallGlyphMetrics, smallGlyphMetricsFormat
    from .E_B_D_T_ import BitmapGlyph, BitmapPlusSmallMetricsMixin, BitmapPlusBigMetricsMixin
    import struct

    class table_C_B_D_T_(E_B_D_T_.table_E_B_D_T_):

    	# Change the data locator table being referenced.
    	locatorName = 'CBLC'

    	# Modify the format class accessor for color bitmap use.
    	def getImageFormatClass(self, imageFormat):
    		try:
    			return E_B_D_T_.table_E_B_D_T_.getImageFormatClass(self, imageFormat)
    		except KeyError:
    			return cbdt_bitmap_classes[imageFormat]

    # Helper method for removing export features not supported by color bitmaps.
    # Write data in the parent class will default to raw if an option is unsupported.
    def _removeUnsupportedForColor(dataFunctions):
    	dataFunctions = dict(dataFunctions)
    	del dataFunctions['row']
    	return dataFunctions

    class ColorBitmapGlyph(BitmapGlyph):

    	fileExtension = '.png'
    	xmlDataFunctions = _removeUnsupportedForColor(BitmapGlyph.xmlDataFunctions)

    class cbdt_bitmap_format_17(BitmapPlusSmallMetricsMixin, ColorBitmapGlyph):

    	def decompile(self):
    		self.metrics = SmallGlyphMetrics()
    		dummy, data = sstruct.unpack2(smallGlyphMetricsFormat, self.data, self.metrics)
    		(dataLen,) = struct.unpack(">L", data[:4])
    		data = data[4:]

    		# For the image data cut it to the size specified by dataLen.
    		assert dataLen <= len(data), "Data overun in format 17"
    		self.imageData = data[:dataLen]

    	def compile(self, ttFont):
    		dataList = []
    		dataList.append(sstruct.pack(smallGlyphMetricsFormat, self.metrics))
    		dataList.append(struct.pack(">L", len(self.imageData)))
    		dataList.append(self.imageData)
    		return bytesjoin(dataList)

    class cbdt_bitmap_format_18(BitmapPlusBigMetricsMixin, ColorBitmapGlyph):

    	def decompile(self):
    		self.metrics = BigGlyphMetrics()
    		dummy, data = sstruct.unpack2(bigGlyphMetricsFormat, self.data, self.metrics)
    		(dataLen,) = struct.unpack(">L", data[:4])
    		data = data[4:]

    		# For the image data cut it to the size specified by dataLen.
    		assert dataLen <= len(data), "Data overun in format 18"
    		self.imageData = data[:dataLen]

    	def compile(self, ttFont):
    		dataList = []
    		dataList.append(sstruct.pack(bigGlyphMetricsFormat, self.metrics))
    		dataList.append(struct.pack(">L", len(self.imageData)))
    		dataList.append(self.imageData)
    		return bytesjoin(dataList)

    class cbdt_bitmap_format_19(ColorBitmapGlyph):

    	def decompile(self):
    		(dataLen,) = struct.unpack(">L", self.data[:4])
    		data = self.data[4:]

    		assert dataLen <= len(data), "Data overun in format 19"
    		self.imageData = data[:dataLen]

    	def compile(self, ttFont):
    		return struct.pack(">L", len(self.imageData)) + self.imageData

    # Dict for CBDT extended formats.
    cbdt_bitmap_classes = {
    	17: cbdt_bitmap_format_17,
    	18: cbdt_bitmap_format_18,
    	19: cbdt_bitmap_format_19,
    }