"""Various low level data validators."""

import os
import calendar


# -------
# Generic
# -------

def isDictEnough(value):
    """
    Some objects will likely come in that aren't
    dicts but are dict-ish enough.
    """
    if isinstance(value, dict):
        return True
    attrs = ("keys", "values", "items")
    for attr in attrs:
        if not hasattr(value, attr):
            return False
    return True

def genericTypeValidator(value, typ):
	"""
	Generic. (Added at version 2.)
	"""
	return isinstance(value, typ)

def genericIntListValidator(values, validValues):
	"""
	Generic. (Added at version 2.)
	"""
	if not isinstance(values, (list, tuple)):
		return False
	valuesSet = set(values)
	validValuesSet = set(validValues)
	if len(valuesSet - validValuesSet) > 0:
		return False
	for value in values:
		if not isinstance(value, int):
			return False
	return True

def genericNonNegativeIntValidator(value):
	"""
	Generic. (Added at version 3.)
	"""
	if not isinstance(value, int):
		return False
	if value < 0:
		return False
	return True

def genericNonNegativeNumberValidator(value):
	"""
	Generic. (Added at version 3.)
	"""
	if not isinstance(value, (int, float)):
		return False
	if value < 0:
		return False
	return True

def genericDictValidator(value, prototype):
	"""
	Generic. (Added at version 3.)
	"""
	# not a dict
	if not isinstance(value, dict):
		return False
	# missing required keys
	for key, (typ, required) in prototype.items():
		if not required:
			continue
		if key not in value:
			return False
	# unknown keys
	for key in value.keys():
		if key not in prototype:
			return False
	# incorrect types
	for key, v in value.items():
		prototypeType = prototype[key][0]
		if not isinstance(v, prototypeType):
			return False
	return True

# --------------
# fontinfo.plist
# --------------

# Data Validators

def fontInfoStyleMapStyleNameValidator(value):
	"""
	Version 2+.
	"""
	options = ["regular", "italic", "bold", "bold italic"]
	return value in options

def fontInfoOpenTypeGaspRangeRecordsValidator(value):
	"""
	Version 3+.
	"""
	if not isinstance(value, list):
		return False
	if len(value) == 0:
		return False
	validBehaviors = [0, 1, 2, 3]
	dictPrototype = dict(rangeMaxPPEM=(int, True), rangeGaspBehavior=(list, True))
	ppemOrder = []
	for rangeRecord in value:
		if not genericDictValidator(rangeRecord, dictPrototype):
			return False
		ppem = rangeRecord["rangeMaxPPEM"]
		behavior = rangeRecord["rangeGaspBehavior"]
		ppemValidity = genericNonNegativeIntValidator(ppem)
		if not ppemValidity:
			return False
		behaviorValidity = genericIntListValidator(behavior, validBehaviors)
		if not behaviorValidity:
			return False
		ppemOrder.append(ppem)
	if ppemOrder != sorted(ppemOrder):
		return False
	if ppemOrder[-1] != 0xFFFF:
		return False
	return True

def fontInfoOpenTypeHeadCreatedValidator(value):
	"""
	Version 2+.
	"""
	# format: 0000/00/00 00:00:00
	if not isinstance(value, basestring):
		return False
	# basic formatting
	if not len(value) == 19:
		return False
	if value.count(" ") != 1:
		return False
	date, time = value.split(" ")
	if date.count("/") != 2:
		return False
	if time.count(":") != 2:
		return False
	# date
	year, month, day = date.split("/")
	if len(year) != 4:
		return False
	if len(month) != 2:
		return False
	if len(day) != 2:
		return False
	try:
		year = int(year)
		month = int(month)
		day = int(day)
	except ValueError:
		return False
	if month < 1 or month > 12:
		return False
	monthMaxDay = calendar.monthrange(year, month)
	if month > monthMaxDay:
		return False
	# time
	hour, minute, second = time.split(":")
	if len(hour) != 2:
		return False
	if len(minute) != 2:
		return False
	if len(second) != 2:
		return False
	try:
		hour = int(hour)
		minute = int(minute)
		second = int(second)
	except ValueError:
		return False
	if hour < 0 or hour > 23:
		return False
	if minute < 0 or minute > 59:
		return False
	if second < 0 or second > 59:
		return True
	# fallback
	return True

def fontInfoOpenTypeNameRecordsValidator(value):
	"""
	Version 3+.
	"""
	if not isinstance(value, list):
		return False
	validKeys = set(["nameID", "platformID", "encodingID", "languageID", "string"])
	dictPrototype = dict(nameID=(int, True), platformID=(int, True), encodingID=(int, True), languageID=(int, True), string=(basestring, True))
	seenRecords = []
	for nameRecord in value:
		if not genericDictValidator(nameRecord, dictPrototype):
			return False
		recordKey = (nameRecord["nameID"], nameRecord["platformID"], nameRecord["encodingID"], nameRecord["languageID"])
		if recordKey in seenRecords:
			return False
		seenRecords.append(recordKey)
	return True

def fontInfoOpenTypeOS2WeightClassValidator(value):
	"""
	Version 2+.
	"""
	if not isinstance(value, int):
		return False
	if value < 0:
		return False
	return True

def fontInfoOpenTypeOS2WidthClassValidator(value):
	"""
	Version 2+.
	"""
	if not isinstance(value, int):
		return False
	if value < 1:
		return False
	if value > 9:
		return False
	return True

def fontInfoVersion2OpenTypeOS2PanoseValidator(values):
	"""
	Version 2.
	"""
	if not isinstance(values, (list, tuple)):
		return False
	if len(values) != 10:
		return False
	for value in values:
		if not isinstance(value, int):
			return False
	# XXX further validation?
	return True

def fontInfoVersion3OpenTypeOS2PanoseValidator(values):
	"""
	Version 3+.
	"""
	if not isinstance(values, (list, tuple)):
		return False
	if len(values) != 10:
		return False
	for value in values:
		if not isinstance(value, int):
			return False
		if value < 0:
			return False
	# XXX further validation?
	return True

def fontInfoOpenTypeOS2FamilyClassValidator(values):
	"""
	Version 2+.
	"""
	if not isinstance(values, (list, tuple)):
		return False
	if len(values) != 2:
		return False
	for value in values:
		if not isinstance(value, int):
			return False
	classID, subclassID = values
	if classID < 0 or classID > 14:
		return False
	if subclassID < 0 or subclassID > 15:
		return False
	return True

def fontInfoPostscriptBluesValidator(values):
	"""
	Version 2+.
	"""
	if not isinstance(values, (list, tuple)):
		return False
	if len(values) > 14:
		return False
	if len(values) % 2:
		return False
	for value in values:
		if not isinstance(value, (int, float)):
			return False
	return True

def fontInfoPostscriptOtherBluesValidator(values):
	"""
	Version 2+.
	"""
	if not isinstance(values, (list, tuple)):
		return False
	if len(values) > 10:
		return False
	if len(values) % 2:
		return False
	for value in values:
		if not isinstance(value, (int, float)):
			return False
	return True

def fontInfoPostscriptStemsValidator(values):
	"""
	Version 2+.
	"""
	if not isinstance(values, (list, tuple)):
		return False
	if len(values) > 12:
		return False
	for value in values:
		if not isinstance(value, (int, float)):
			return False
	return True

def fontInfoPostscriptWindowsCharacterSetValidator(value):
	"""
	Version 2+.
	"""
	validValues = range(1, 21)
	if value not in validValues:
		return False
	return True

def fontInfoWOFFMetadataUniqueIDValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(id=(basestring, True))
	if not genericDictValidator(value, dictPrototype):
		return False
	return True

def fontInfoWOFFMetadataVendorValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = {"name" : (basestring, True), "url" : (basestring, False), "dir" : (basestring, False), "class" : (basestring, False)}
	if not genericDictValidator(value, dictPrototype):
		return False
	if "dir" in value and value.get("dir") not in ("ltr", "rtl"):
		return False
	return True

def fontInfoWOFFMetadataCreditsValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(credits=(list, True))
	if not genericDictValidator(value, dictPrototype):
		return False
	if not len(value["credits"]):
		return False
	dictPrototype = {"name" : (basestring, True), "url" : (basestring, False), "role" : (basestring, False), "dir" : (basestring, False), "class" : (basestring, False)}
	for credit in value["credits"]:
		if not genericDictValidator(credit, dictPrototype):
			return False
		if "dir" in credit and credit.get("dir") not in ("ltr", "rtl"):
			return False
	return True

def fontInfoWOFFMetadataDescriptionValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(url=(basestring, False), text=(list, True))
	if not genericDictValidator(value, dictPrototype):
		return False
	for text in value["text"]:
		if not fontInfoWOFFMetadataTextValue(text):
			return False
	return True

def fontInfoWOFFMetadataLicenseValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(url=(basestring, False), text=(list, False), id=(basestring, False))
	if not genericDictValidator(value, dictPrototype):
		return False
	if "text" in value:
		for text in value["text"]:
			if not fontInfoWOFFMetadataTextValue(text):
				return False
	return True

def fontInfoWOFFMetadataTrademarkValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(text=(list, True))
	if not genericDictValidator(value, dictPrototype):
		return False
	for text in value["text"]:
		if not fontInfoWOFFMetadataTextValue(text):
			return False
	return True

def fontInfoWOFFMetadataCopyrightValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(text=(list, True))
	if not genericDictValidator(value, dictPrototype):
		return False
	for text in value["text"]:
		if not fontInfoWOFFMetadataTextValue(text):
			return False
	return True

def fontInfoWOFFMetadataLicenseeValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = {"name" : (basestring, True), "dir" : (basestring, False), "class" : (basestring, False)}
	if not genericDictValidator(value, dictPrototype):
		return False
	if "dir" in value and value.get("dir") not in ("ltr", "rtl"):
		return False
	return True

def fontInfoWOFFMetadataTextValue(value):
	"""
	Version 3+.
	"""
	dictPrototype = {"text" : (basestring, True), "language" : (basestring, False), "dir" : (basestring, False), "class" : (basestring, False)}
	if not genericDictValidator(value, dictPrototype):
		return False
	if "dir" in value and value.get("dir") not in ("ltr", "rtl"):
		return False
	return True

def fontInfoWOFFMetadataExtensionsValidator(value):
	"""
	Version 3+.
	"""
	if not isinstance(value, list):
		return False
	if not value:
		return False
	for extension in value:
		if not fontInfoWOFFMetadataExtensionValidator(extension):
			return False
	return True

def fontInfoWOFFMetadataExtensionValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(names=(list, False), items=(list, True))
	if not genericDictValidator(value, dictPrototype):
		return False
	if "names" in value:
		for name in value["names"]:
			if not fontInfoWOFFMetadataExtensionNameValidator(name):
				return False
	for item in value["items"]:
		if not fontInfoWOFFMetadataExtensionItemValidator(item):
			return False
	return True

def fontInfoWOFFMetadataExtensionItemValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(id=(basestring, False), names=(list, True), values=(list, True))
	if not genericDictValidator(value, dictPrototype):
		return False
	for name in value["names"]:
		if not fontInfoWOFFMetadataExtensionNameValidator(name):
			return False
	for value in value["values"]:
		if not fontInfoWOFFMetadataExtensionValueValidator(name):
			return False
	return True

def fontInfoWOFFMetadataExtensionNameValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = {"text" : (basestring, True), "language" : (basestring, False), "dir" : (basestring, False), "class" : (basestring, False)}
	if not genericDictValidator(value, dictPrototype):
		return False
	return True

def fontInfoWOFFMetadataExtensionValueValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = {"text" : (basestring, True), "language" : (basestring, False), "dir" : (basestring, False), "class" : (basestring, False)}
	if not genericDictValidator(value, dictPrototype):
		return False
	return True

# ----------
# Guidelines
# ----------

def guidelinesValidator(value, identifiers=None):
	"""
	Version 3+.
	"""
	if not isinstance(value, list):
		return False
	if identifiers is None:
		identifiers = set()
	for guide in value:
		if not guidelineValidator(guide):
			return False
		identifier = guide.get("identifier")
		if identifier is not None:
			if identifier in identifiers:
				return False
			identifiers.add(identifier)
	return True

def guidelineValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(
		x=((int, float), False), y=((int, float), False), angle=((int, float), False),
		name=(basestring, False), color=(basestring, False), identifier=(basestring, False)
	)
	if not genericDictValidator(value, dictPrototype):
		return False
	x = value.get("x")
	y = value.get("y")
	angle = value.get("angle")
	# x or y must be present
	if x is None and y is None:
		return False
	# if x or y are None, angle must not be present
	if x is None or y is None:
		if angle is not None:
			return False
	# if x and y are defined, angle must be defined
	if x is not None and y is not None and angle is None:
		return False
	# angle must be between 0 and 360
	if angle is not None:
		if angle < 0:
			return False
		if angle > 360:
			return False
	# identifier must be 1 or more characters
	identifier = value.get("identifier")
	if identifier is not None and not identifierValidator(identifier):
		return False
	# color must follow the proper format
	color = value.get("color")
	if color is not None and not colorValidator(color):
		return False
	return True

# ----------
# Identifier
# ----------

def identifierValidator(value):
	"""
	Version 3+.

	>>> identifierValidator("a")
	True
	>>> identifierValidator("")
	False
	>>> identifierValidator("a" * 101)
	False
	"""
	validCharactersMin = 0x20
	validCharactersMax = 0x7E
	if not isinstance(value, basestring):
		return False
	if not value:
		return False
	if len(value) > 100:
		return False
	for c in value:
		c = ord(c)
		if c < validCharactersMin or c > validCharactersMax:
			return False
	return True

# -----
# Color
# -----

def colorValidator(value):
	"""
	Version 3+.

	>>> colorValidator("0,0,0,0")
	True
	>>> colorValidator(".5,.5,.5,.5")
	True
	>>> colorValidator("0.5,0.5,0.5,0.5")
	True
	>>> colorValidator("1,1,1,1")
	True

	>>> colorValidator("2,0,0,0")
	False
	>>> colorValidator("0,2,0,0")
	False
	>>> colorValidator("0,0,2,0")
	False
	>>> colorValidator("0,0,0,2")
	False

	>>> colorValidator("1r,1,1,1")
	False
	>>> colorValidator("1,1g,1,1")
	False
	>>> colorValidator("1,1,1b,1")
	False
	>>> colorValidator("1,1,1,1a")
	False

	>>> colorValidator("1 1 1 1")
	False
	>>> colorValidator("1 1,1,1")
	False
	>>> colorValidator("1,1 1,1")
	False
	>>> colorValidator("1,1,1 1")
	False

	>>> colorValidator("1, 1, 1, 1")
	True
	"""
	if not isinstance(value, basestring):
		return False
	parts = value.split(",")
	if len(parts) != 4:
		return False
	for part in parts:
		part = part.strip()
		converted = False
		try:
			part = int(part)
			converted = True
		except ValueError:
			pass
		if not converted:
			try:
				part = float(part)
				converted = True
			except ValueError:
				pass
		if not converted:
			return False
		if part < 0:
			return False
		if part > 1:
			return False
	return True

# -----
# image
# -----

def imageValidator(value):
	"""
	Version 3+.
	"""
	dictPrototype = dict(
		fileName=(basestring, True),
		xScale=((int, float), False), xyScale=((int, float), False), yxScale=((int, float), False), yScale=((int, float), False),
		xOffset=((int, float), False), yOffset=((int, float), False),
		color=(basestring, False)
	)
	if not genericDictValidator(value, dictPrototype):
		return False
	# fileName must be one or more characters
	if not value["fileName"]:
		return False
	# color must follow the proper format
	color = value.get("color")
	if color is not None and not colorValidator(color):
		return False
	return True

def pngValidator(path=None, data=None, fileObj=None):
	"""
	Version 3+.

	This checks the signature of the image data.
	"""
	print path
	assert path is not None or data is not None or fileObj is not None
	if path is not None:
		f = open(path, "rb")
		signature = f.read(8)
		f.close()
	elif data is not None:
		signature = data[:8]
	elif fileObj is not None:
		pos = fileObj.tell()
		signature = fileObj.read(8)
		fileObj.seek(pos)
	if signature != "\x89PNG\r\n\x1a\n":
		return False, "Image does not begin with the PNG signature."
	return True, None

# -------------------
# layercontents.plist
# -------------------

def layerContentsValidator(value, ufoPath):
	"""
	Check the validity of layercontents.plist.
	Version 3+.
	"""
	bogusFileMessage = "layercontents.plist in not in the correct format."
	# file isn't in the right format
	if not isinstance(value, list):
		return False, bogusFileMessage
	# work through each entry
	usedLayerNames = set()
	usedDirectories = set()
	contents = {}
	for entry in value:
		# layer entry in the incorrect format
		if not isinstance(entry, list):
			return False, bogusFileMessage
		if not len(entry) == 2:
			return False, bogusFileMessage
		for i in entry:
			if not isinstance(i, basestring):
				return False, bogusFileMessage
		layerName, directoryName = entry
		# check directory naming
		if not directoryName.startswith("glyphs"):
			return False, "Invalid directory name (%s) in layercontents.plist." % directoryName
		if directoryName != "glyphs":
			if not directoryName.startswith("glyphs."):
				return False, "Invalid directory name (%s) in layercontents.plist." % directoryName
		if len(layerName) == 0:
			return False, "Empty layer name in layercontents.plist."
		# directory doesn't exist
		p = os.path.join(ufoPath, directoryName)
		if not os.path.exists(p):
			return False, "A glyphset does not exist at %s." % directoryName
		# empty name
		if not len(layerName):
			return False, "A layer has an empty name."
		# default layer name
		if layerName == "public.default" and directoryName != "glyphs":
		    return False, "The name public.default is being used by a layer that is not the default."
		# check usage
		if layerName in usedLayerNames:
			return False, "The layer name %s is used by more than one layer." % layerName
		usedLayerNames.add(layerName)
		if directoryName in usedDirectories:
			return False, "The directory %s is used by more than one layer." % directoryName
		usedDirectories.add(directoryName)
		# store
		contents[layerName] = directoryName
	# missing default layer
	foundDefault = False
	for layerName, directory in contents.items():
		if directory == "glyphs":
			foundDefault = True
			break
	if not foundDefault:
		return False, "The required default glyph set is not in the UFO."
	return True, None

# ------------
# groups.plist
# ------------

def groupsValidator(value):
	"""
	Check the validity of the groups.
	Version 3+ (though it's backwards compatible with UFO 1 and UFO 2).

	>>> groups = {"A" : ["A", "A"], "A2" : ["A"]}
	>>> groupsValidator(groups)
	(True, None)

	>>> groups = {"" : ["A"]}
	>>> groupsValidator(groups)
	(False, 'A group has an empty name.')

	>>> groups = {"public.awesome" : ["A"]}
	>>> groupsValidator(groups)
	(True, None)

	>>> groups = {"public.kern1." : ["A"]}
	>>> groupsValidator(groups)
	(False, 'The group data contains a kerning group with an incomplete name.')
	>>> groups = {"public.kern2." : ["A"]}
	>>> groupsValidator(groups)
	(False, 'The group data contains a kerning group with an incomplete name.')

	>>> groups = {"public.kern1.A" : ["A"], "public.kern2.A" : ["A"]}
	>>> groupsValidator(groups)
	(True, None)

	>>> groups = {"public.kern1.A1" : ["A"], "public.kern1.A2" : ["A"]}
	>>> groupsValidator(groups)
	(False, 'The glyph "A" occurs in too many kerning groups.')
	"""
	bogusFormatMessage = "The group data is not in the correct format."
	if not isDictEnough(value):
		return False, bogusFormatMessage
	firstSideMapping = {}
	secondSideMapping = {}
	for groupName, glyphList in value.items():
		if not isinstance(groupName, basestring):
			return False, bogusFormatMessage
		if not isinstance(glyphList, (list, tuple)):
			return False, bogusFormatMessage
		if not groupName:
			return False, "A group has an empty name."
		if groupName.startswith("public."):
			if not groupName.startswith("public.kern1.") and not groupName.startswith("public.kern2."):
				# unknown pubic.* name. silently skip.
				continue
			else:
				if len("public.kernN.") == len(groupName):
					return False, "The group data contains a kerning group with an incomplete name."
			if groupName.startswith("public.kern1."):
				d = firstSideMapping
			else:
				d = secondSideMapping
			for glyphName in glyphList:
				if not isinstance(glyphName, basestring):
					return False, "The group data %s contains an invalid member." % groupName
				if glyphName in d:
					return False, "The glyph \"%s\" occurs in too many kerning groups." % glyphName
				d[glyphName] = groupName
	return True, None

# -------------
# lib.plist/lib
# -------------

def libValidator(value):
	"""
	Check the validity of the lib.
	Version 3+ (though it's backwards compatible with UFO 1 and UFO 2).

	>>> lib = {"foo" : "bar"}
	>>> libValidator(lib)
	(True, None)

	>>> lib = {"public.awesome" : "hello"}
	>>> libValidator(lib)
	(True, None)

	>>> lib = {"public.glyphOrder" : ["A", "C", "B"]}
	>>> libValidator(lib)
	(True, None)

	>>> lib = {"public.glyphOrder" : "hello"}
	>>> libValidator(lib)
	(False, 'public.glyphOrder is not properly formatted.')

	>>> lib = {"public.glyphOrder" : ["A", 1, "B"]}
	>>> libValidator(lib)
	(False, 'public.glyphOrder is not properly formatted.')
	"""
	bogusFormatMessage = "The lib data is not in the correct format."
	if not isDictEnough(value):
		return False, bogusFormatMessage
	for key, value in value.items():
		if not isinstance(key, basestring):
			return False, bogusFormatMessage
		# public.glyphOrder
		if key == "public.glyphOrder":
			bogusGlyphOrderMessage = "public.glyphOrder is not properly formatted."
			if not isinstance(value, (list, tuple)):
				return False, bogusGlyphOrderMessage
			for glyphName in value:
				if not isinstance(glyphName, basestring):
					return False, bogusGlyphOrderMessage
	return True, None

if __name__ == "__main__":
	import doctest
	doctest.testmod()