# Source code for fontTools.merge

    # Copyright 2013 Google, Inc. All Rights Reserved.
    #
    # Google Author(s): Behdad Esfahbod, Roozbeh Pournader

    from fontTools import ttLib
    import fontTools.merge.base
    from fontTools.merge.cmap import computeMegaGlyphOrder, computeMegaCmap, renameCFFCharStrings
    from fontTools.merge.layout import layoutPreMerge, layoutPostMerge
    from fontTools.merge.options import Options
    import fontTools.merge.tables
    from fontTools.misc.loggingTools import Timer
    from functools import reduce
    import sys
    import logging

    log = logging.getLogger("fontTools.merge")
    timer = Timer(logger=logging.getLogger(__name__+".timer"), level=logging.INFO)

    class Merger(object):
    	"""Font merger.

    	This class merges multiple files into a single OpenType font, taking into
    	account complexities such as OpenType layout (``GSUB``/``GPOS``) tables and
    	cross-font metrics (e.g. ``hhea.ascent`` is set to the maximum value across
    	all the fonts).

    	If multiple glyphs map to the same Unicode value, and the glyphs are considered
    	sufficiently different (that is, they differ in any of paths, widths, or
    	height), then subsequent glyphs are renamed and a lookup in the ``locl``
    	feature will be created to disambiguate them. For example, if the arguments
    	are an Arabic font and a Latin font and both contain a set of parentheses,
    	the Latin glyphs will be renamed to ``parenleft#1`` and ``parenright#1``,
    	and a lookup will be inserted into the to ``locl`` feature (creating it if
    	necessary) under the ``latn`` script to substitute ``parenleft`` with
    	``parenleft#1`` etc.

    	Restrictions:

    	- All fonts must have the same units per em.
    	- If duplicate glyph disambiguation takes place as described above then the
    		fonts must have a ``GSUB`` table.

    	Attributes:
    		options: Currently unused.
    	"""

    	def __init__(self, options=None):

    		if not options:
    			options = Options()

    		self.options = options

    	def _openFonts(self, fontfiles):
    		fonts = [ttLib.TTFont(fontfile) for fontfile in fontfiles]
    		for font,fontfile in zip(fonts, fontfiles):
    			font._merger__fontfile = fontfile
    			font._merger__name = font['name'].getDebugName(4)
    		return fonts

    	def merge(self, fontfiles):
    		"""Merges fonts together.

    		Args:
    			fontfiles: A list of file names to be merged

    		Returns:
    			A :class:`fontTools.ttLib.TTFont` object. Call the ``save`` method on
    			this to write it out to an OTF file.
    		"""
    		#
    		# Settle on a mega glyph order.
    		#
    		fonts = self._openFonts(fontfiles)
    		glyphOrders = [list(font.getGlyphOrder()) for font in fonts]
    		computeMegaGlyphOrder(self, glyphOrders)

    		# Take first input file sfntVersion
    		sfntVersion = fonts[0].sfntVersion

    		# Reload fonts and set new glyph names on them.
    		fonts = self._openFonts(fontfiles)
    		for font,glyphOrder in zip(fonts, glyphOrders):
    			font.setGlyphOrder(glyphOrder)
    			if 'CFF ' in font:
    				renameCFFCharStrings(self, glyphOrder, font['CFF '])

    		cmaps = [font['cmap'] for font in fonts]
    		self.duplicateGlyphsPerFont = [{} for _ in fonts]
    		computeMegaCmap(self, cmaps)

    		mega = ttLib.TTFont(sfntVersion=sfntVersion)
    		mega.setGlyphOrder(self.glyphOrder)

    		for font in fonts:
    			self._preMerge(font)

    		self.fonts = fonts

    		allTags = reduce(set.union, (list(font.keys()) for font in fonts), set())
    		allTags.remove('GlyphOrder')

    		for tag in allTags:
    			if tag in self.options.drop_tables:
    				continue

    			with timer("merge '%s'" % tag):
    				tables = [font.get(tag, NotImplemented) for font in fonts]

    				log.info("Merging '%s'.", tag)
    				clazz = ttLib.getTableClass(tag)
    				table = clazz(tag).merge(self, tables)
    				# XXX Clean this up and use:  table = mergeObjects(tables)

    				if table is not NotImplemented and table is not False:
    					mega[tag] = table
    					log.info("Merged '%s'.", tag)
    				else:
    					log.info("Dropped '%s'.", tag)

    		del self.duplicateGlyphsPerFont
    		del self.fonts

    		self._postMerge(mega)

    		return mega

    	def mergeObjects(self, returnTable, logic, tables):
    		# Right now we don't use self at all.  Will use in the future
    		# for options and logging.

    		allKeys = set.union(set(), *(vars(table).keys() for table in tables if table is not NotImplemented))
    		for key in allKeys:
    			try:
    				mergeLogic = logic[key]
    			except KeyError:
    				try:
    					mergeLogic = logic['*']
    				except KeyError:
    					raise Exception("Don't know how to merge key %s of class %s" %
    							(key, returnTable.__class__.__name__))
    			if mergeLogic is NotImplemented:
    				continue
    			value = mergeLogic(getattr(table, key, NotImplemented) for table in tables)
    			if value is not NotImplemented:
    				setattr(returnTable, key, value)

    		return returnTable

    	def _preMerge(self, font):
    		layoutPreMerge(font)

    	def _postMerge(self, font):
    		layoutPostMerge(font)

    		if "OS/2" in font:
    			# https://github.com/fonttools/fonttools/issues/2538
    			# TODO: Add an option to disable this?
    			font["OS/2"].recalcAvgCharWidth(font)

    __all__ = [
    	'Options',
    	'Merger',
    	'main'
    ]

    @timer("make one with everything (TOTAL TIME)")
    def main(args=None):
    	"""Merge multiple fonts into one"""
    	from fontTools import configLogger

    	if args is None:
    		args = sys.argv[1:]

    	options = Options()
    	args = options.parse_opts(args, ignore_unknown=['output-file'])
    	outfile = 'merged.ttf'
    	fontfiles = []
    	for g in args:
    		if g.startswith('--output-file='):
    			outfile = g[14:]
    			continue
    		fontfiles.append(g)

    	if len(args) < 1:
    		print("usage: pyftmerge font...", file=sys.stderr)
    		return 1

    	configLogger(level=logging.INFO if options.verbose else logging.WARNING)
    	if options.timing:
    		timer.logger.setLevel(logging.DEBUG)
    	else:
    		timer.logger.disabled = True

    	merger = Merger(options=options)
    	font = merger.merge(fontfiles)
    	with timer("compile and save font"):
    		font.save(outfile)

    if __name__ == "__main__":
    	sys.exit(main())