#!/usr/bin/python
# -*- coding: utf8 -*-

from __future__ import (unicode_literals, division, absolute_import, print_function)

import collections
import decimal
import functools
from lxml import etree
import re

from .epub_output import (EPUB_NS_URI, EPUB_TYPE, IDX_ENTRY, MATH, qname, SVG, XML_LANG, XML_NS_URI, value_str)
from .ion import (ion_type, IonBool, IonDecimal, IonFloat, IonInt, IonList, IonString, IonStruct, IonSymbol, isstring)
from .message_logging import log
from .utilities import (get_url_filename, list_symbols, natural_sort_key, remove_duplicates, type_name, urlabspath, urlrelpath)


__license__ = "GPL v3"
__copyright__ = "2016-2024, John Howell <jhowell@acm.org>"


STYLE_TEST = False
KEEP_STYLES_INLINE = False
EMIT_OEB_PAGE_PROPS = False
DETECT_LAYOUT_ENHANCER = False
FIX_PT_TO_PX = True
REMOVE_EMPTY_NAMED_CLASSES = True

REVERSE_INHERITANCE = True
REVERSE_INHERITANCE_FRACTION = 0.8

FIX_NONSTANDARD_FONT_WEIGHT = False

USE_NORMAL_LINE_HEIGHT = True

LINE_HEIGHT_SCALE_FACTOR = decimal.Decimal("1.2")
NORMAL_LINE_HEIGHT_EM = "%sem" % LINE_HEIGHT_SCALE_FACTOR

PX_PER_PERCENT = 8.534

MINIMUM_LINE_HEIGHT = decimal.Decimal("1.0")

CVT_DIRECTION_PROPERTY_TO_MARKUP = False

DEFAULT_DOCUMENT_FONT_FAMILY = "serif"
DEFAULT_DOCUMENT_LINE_HEIGHT = "normal" if USE_NORMAL_LINE_HEIGHT else NORMAL_LINE_HEIGHT_EM
DEFAULT_DOCUMENT_FONT_SIZE = "1em"

DEFAULT_KC_COMIC_FONT_SIZE = "16px"

DEFAULT_CLASS_NAME_PREFIX = "class"

ALPHA_MASK = 0xff000000


class Prop(object):

    def __init__(self, name, values=None):
        self.name = name
        self.values = values


COLLISIONS = {
    "$352": "always",
    "$652": "queue",
    }


BORDER_STYLES = {
    "$349": "none",
    "$328": "solid",
    "$331": "dotted",
    "$330": "dashed",
    "$329": "double",
    "$335": "ridge",
    "$334": "groove",
    "$336": "inset",
    "$337": "outset",
    }


LAYOUT_HINT_ELEMENT_NAMES = {
    "$453": "caption",
    "$282": "figure",
    "$760": "heading",
}


YJ_PROPERTY_INFO = {
    "$479": Prop("background-image"),
    "$480": Prop("-kfx-background-positionx"),
    "$481": Prop("-kfx-background-positiony"),

    "$547": Prop("background-origin", {
        "$378": "border-box",
        "$377": "content-box",
        "$379": "padding-box",
        }),

    "$484": Prop("background-repeat", {
        "$487": "no-repeat",
        "$485": "repeat-x",
        "$486": "repeat-y",
        }),

    "$482": Prop("-kfx-background-sizex"),
    "$483": Prop("-kfx-background-sizey"),

    "$31": Prop("-kfx-baseline-shift"),

    "$44": Prop("-kfx-baseline-style", {
        "$60": "bottom",
        "$320": "middle",
        "$350": "baseline",
        "$371": "sub",
        "$370": "super",
        "$449": "text-bottom",
        "$447": "text-top",
        "$58": "top",
        }),

    "$682": Prop("direction", {
        "$376": "ltr",
        "$375": "rtl",
        }),

    "$674": Prop("unicode-bidi", {
        "$675": "embed",
        "$676": "isolate",
        "$678": "isolate-override",
        "$350": "normal",
        "$677": "bidi-override",
        "$679": "plaintext",
        }),

    "$83": Prop("border-color"),
    "$86": Prop("border-bottom-color"),
    "$85": Prop("border-left-color"),
    "$87": Prop("border-right-color"),
    "$84": Prop("border-top-color"),

    "$461": Prop("border-bottom-left-radius"),
    "$462": Prop("border-bottom-right-radius"),
    "$459": Prop("border-top-left-radius"),
    "$460": Prop("border-top-right-radius"),

    "$457": Prop("-webkit-border-horizontal-spacing"),
    "$456": Prop("-webkit-border-vertical-spacing"),

    "$88": Prop("border-style", BORDER_STYLES),
    "$91": Prop("border-bottom-style", BORDER_STYLES),
    "$90": Prop("border-left-style", BORDER_STYLES),
    "$92": Prop("border-right-style", BORDER_STYLES),
    "$89": Prop("border-top-style", BORDER_STYLES),

    "$93": Prop("border-width"),
    "$96": Prop("border-bottom-width"),
    "$95": Prop("border-left-width"),
    "$97": Prop("border-right-width"),
    "$94": Prop("border-top-width"),

    "$60": Prop("bottom"),
    "$580": Prop("-kfx-box-align", {
        "$320": "center",
        "$59": "left",
        "$61": "right",
        }),

    "$133": Prop("page-break-after", {
        "$352": "always",
        "$383": "auto",
        "$353": "avoid",
        }),

    "$134": Prop("page-break-before", {
        "$352": "always",
        "$383": "auto",
        "$353": "avoid",
        }),

    "$135": Prop("page-break-inside", {
        "$383": "auto",
        "$353": "avoid",
        }),

    "$708": Prop("-kfx-character-width", {
        "$383": None,
        }),

    "$476": Prop("overflow", {
        False: "visible",
        True: "hidden",
        }),

    "$112": Prop("column-count", {
        "$383": "auto",
        }),

    "$116": Prop("column-rule-color"),

    "$192": Prop("direction", {
        "$376": "ltr",
        "$375": "rtl",
        }),

    "$99": Prop("box-decoration-break", {
        False: "slice",
        True: "clone",
        }),

    "$73": Prop("background-clip", {
        "$378": "border-box",
        "$377": "content-box",
        "$379": "padding-box",
        }),

    "$70": Prop("-kfx-fill-color"),
    "$72": Prop("-kfx-fill-opacity"),

    "$140": Prop("float", {
        "$59": "left",
        "$61": "right",
        "$786": "snap-block",
        }),

    "$11": Prop("font-family"),
    "$16": Prop("font-size"),

    "$15": Prop("font-stretch", {
        "$365": "condensed",
        "$368": "expanded",
        "$350": "normal",
        "$366": "semi-condensed",
        "$367": "semi-expanded",
        }),

    "$12": Prop("font-style", {
        "$382": "italic",
        "$350": "normal",
        "$381": "oblique",
         }),

    "$13": Prop("font-weight", {
        "$361": "bold",
        "$363": "900",
        "$357": "300",
        "$359": "500",
        "$350": "normal",
        "$360": "600",
        "$355": "100",
        "$362": "800",
        "$356": "200",
        }),

    "$583": Prop("font-variant", {
        "$349": "normal",
        "$369": "small-caps"}),

    "$57": Prop("height"),

    "$458": Prop("empty-cells", {
        False: "show",
        True: "hide",
        }),

    "$127": Prop("hyphens", {
        "$383": "auto",
        "$384": "manual",
        "$349": "none",
        }),

    "$785": Prop("-kfx-keep-lines-together"),

    "$10": Prop("-kfx-attrib-xml-lang"),
    "$761": Prop("-kfx-layout-hints"),
    "$59": Prop("left"),
    "$32": Prop("letter-spacing"),

    "$780": Prop("line-break", {
        "$783": "anywhere",
        "$383": "auto",
        "$781": "loose",
        "$350": "normal",
        "$782": "strict",
        }),

    "$42": Prop("line-height", {
        "$383": "normal",
        }),

    "$577": Prop("-kfx-link-color"),
    "$576": Prop("-kfx-visited-color"),

    "$100": Prop("list-style-type", {
        "$346": "lower-alpha",
        "$347": "upper-alpha",
        "$342": "circle",
        "$737": "cjk-earthly-branch",
        "$738": "cjk-heavenly-stem",
        "$736": "cjk-ideographic",
        "$796": "decimal-leading-zero",
        "$340": "disc",
        "$795": "georgian",
        "$739": "hiragana",
        "$740": "hiragana-iroha",
        "$271": None,
        "$743": "japanese-formal",
        "$744": "japanese-informal",
        "$741": "katakana",
        "$742": "katakana-iroha",
        "$793": "lower-armenian",
        "$791": "lower-greek",
        "$349": "none",
        "$343": "decimal",
        "$344": "lower-roman",
        "$345": "upper-roman",
        "$746": "simp-chinese-formal",
        "$745": "simp-chinese-informal",
        "$341": "square",
        "$748": "trad-chinese-formal",
        "$747": "trad-chinese-informal",
        "$794": "upper-armenian",
        "$792": "upper-greek",
        }),

    "$503": Prop("list-style-image"),

    "$551": Prop("list-style-position", {
        "$552": "inside",
        "$553": "outside",
        }),

    "$46": Prop("margin"),
    "$49": Prop("margin-bottom"),
    "$48": Prop("margin-left"),
    "$50": Prop("margin-right"),
    "$47": Prop("margin-top"),

    "$64": Prop("max-height"),
    "$65": Prop("max-width"),
    "$62": Prop("min-height"),
    "$63": Prop("min-width"),

    "$45": Prop("white-space", {
        False: "normal",
        True: "nowrap",
        }),

    "$105": Prop("outline-color"),
    "$106": Prop("outline-offset"),
    "$107": Prop("outline-style", BORDER_STYLES),
    "$108": Prop("outline-width"),

    "$554": Prop("text-decoration", {
        "$330": "overline dashed",
        "$331": "overline dotted",
        "$329": "overline double",
        "$349": None,
        "$328": "overline",
        }),

    "$555": Prop("text-decoration-color"),

    "$51": Prop("padding"),
    "$54": Prop("padding-bottom"),
    "$53": Prop("padding-left"),
    "$55": Prop("padding-right"),
    "$52": Prop("padding-top"),

    "$183": Prop("position", {
        "$324": "absolute",
        "$455": "oeb-page-foot",
        "$151": "oeb-page-head",
        "$488": "relative",
        "$489": "fixed",
        }),

    "$61": Prop("right"),

    "$766": Prop("ruby-align", {
        "$320": "center",
        "$773": "space-around",
        "$774": "space-between",
        "$680": "start",
        }),

    "$764": Prop("ruby-merge", {
        "$772": "collapse",
        "$771": "separate",
        }),

    "$762": Prop("ruby-position", {
        "$60": "under",
        "$58": "over",
        }),

    "$763": Prop("ruby-position", {
        "$59": "under",
        "$61": "over",
        }),

    "$765": Prop("ruby-align", {
        "$320": "center",
        "$773": "space-around",
        "$774": "space-between",
        "$680": "start",
        }),

    "$496": Prop("box-shadow"),

    "$546": Prop("box-sizing", {
        "$378": "border-box",
        "$377": "content-box",
        "$379": "padding-box",
        }),

    "src": Prop("src"),

    "$27": Prop("text-decoration", {
        "$330": "line-through dashed",
        "$331": "line-through dotted",
        "$329": "line-through double",
        "$349": None,
        "$328": "line-through"}),

    "$28": Prop("text-decoration-color"),

    "$75": Prop("-webkit-text-stroke-color"),

    "$531": Prop("-svg-stroke-dasharray"),

    "$532": Prop("-svg-stroke-dashoffset"),

    "$77": Prop("-svg-stroke-linecap", {
        "$534": "butt",
        "$533": "round",
        "$341": "square",
        }),

    "$529": Prop("-svg-stroke-linejoin", {
        "$536": "bevel",
        "$535": "miter",
        "$533": "round",
        }),

    "$530": Prop("-svg-stroke-miterlimit"),

    "$76": Prop("-webkit-text-stroke-width"),

    "$173": Prop("-kfx-style-name"),

    "$150": Prop("border-collapse", {
        False: "separate",
        True: "collapse",
        }),

    "$148": Prop("-kfx-attrib-colspan"),
    "$149": Prop("-kfx-attrib-rowspan"),

    "$34": Prop("text-align", {
        "$320": "center",
        "$321": "justify",
        "$59": "left",
        "$61": "right",
        }),

    "$35": Prop("text-align-last", {
        "$383": "auto",
        "$320": "center",
        "$681": "end",
        "$321": "justify",
        "$59": "left",
        "$61": "right",
        "$680": "start",
        }),

    "$21": Prop("background-color"),
    "$528": Prop("background-image"),
    "$19": Prop("color"),

    "$707": Prop("text-combine-upright", {
        "$573": "all",
        }),

    "$718": Prop("text-emphasis-color"),

    "$719": Prop("-kfx-text-emphasis-position-horizontal", {
        "$58": "over",
        "$60": "under",
        }),

    "$720": Prop("-kfx-text-emphasis-position-vertical", {
        "$59": "left",
        "$61": "right",
        }),

    "$717": Prop("text-emphasis-style", {
        "$724": "filled",
        "$728": "filled circle",
        "$726": "filled dot",
        "$730": "filled double-circle",
        "$734": "filled sesame",
        "$732": "filled triangle",
        "$725": "open",
        "$729": "open circle",
        "$727": "open dot",
        "$731": "open double-circle",
        "$735": "open sesame",
        "$733": "open triangle",
        }),

    "$706": Prop("text-orientation", {
        "$383": "mixed",
        "$778": "sideways",
        "$779": "upright",
        }),

    "$36": Prop("text-indent"),

    "$41": Prop("text-transform", {
        "$373": "lowercase",
        "$349": "none",
        "$374": "capitalize",
        "$372": "uppercase",
        }),

    "$497": Prop("text-shadow"),
    "$58": Prop("top"),
    "$98": Prop("transform"),
    "$549": Prop("transform-origin"),

    "$23": Prop("text-decoration", {
        "$330": "underline dashed",
        "$331": "underline dotted",
        "$329": "underline double",
        "$349": None,
        "$328": "underline",
        }),

    "$24": Prop("text-decoration-color"),

    "$68": Prop("visibility", {
        False: "hidden",
        True: "visible"}),

    "$716": Prop("white-space", {
        "$715": "nowrap",
        }),

    "$56": Prop("width"),

    "$569": Prop("word-break", {
        "$570": "break-all",
        "$350": "normal",
        }),

    "$33": Prop("word-spacing"),

    "$560": Prop("writing-mode", {
        "$557": "horizontal-tb",
        "$559": "vertical-rl",
        "$558": "vertical-lr"}),

    "$650": Prop("-amzn-shape-outside"),

    "$646": Prop("-kfx-collision"),

    "$616": Prop("-kfx-attrib-epub-type", {
        "$617": "noteref"}),

    "$658": Prop("yj-float-align", {
        "$58": None,
        }),

    "$672": Prop("yj-float-bias", {
        "$671": None,
        }),

    "$628": Prop("clear", {
        "$59": "left",
        "$61": "right",
        "$421": "both",
        "$349": "none",
        }),

    "$673": Prop("yj-float-to-block", {
        False: None}),

    "$644": Prop("-amzn-page-footer", {
        "$442": "disable",
        "$441": "overlay",
        }),

    "$643": Prop("-amzn-page-header", {
        "$442": "disable",
        "$441": "overlay",
        }),

    "$645": Prop("-amzn-max-crop-percentage"),

    "$790": Prop("-kfx-heading-level"),

    "$640": Prop("-kfx-user-margin-bottom-percentage"),
    "$641": Prop("-kfx-user-margin-left-percentage"),
    "$642": Prop("-kfx-user-margin-right-percentage"),
    "$639": Prop("-kfx-user-margin-top-percentage"),

    "$633": Prop("-kfx-table-vertical-align", {
        "$350": "baseline",
        "$60": "bottom",
        "$320": "middle",
        "$58": "top",
        }),

    "$649": Prop("-kfx-attrib-epub-type", {
        "$442": "amzn:decorative",
        "$441": "amzn:not-decorative",
        }),

    "$788": Prop("page-break-after", {
        "$352": "always",
        "$383": "auto",
        "$353": "avoid",
        }),

    "$789": Prop("page-break-before", {
        "$352": "always",
        "$383": "auto",
        "$353": "avoid",
        }),
    }

YJ_PROPERTY_NAMES = set(YJ_PROPERTY_INFO.keys())


YJ_LENGTH_UNITS = {
    "$506": "ch",
    "$315": "cm",
    "$308": "em",
    "$309": "ex",
    "$317": "in",
    "$310": "lh",
    "$316": "mm",
    "$314": "%",
    "$318": "pt",
    "$319": "px",
    "$505": "rem",
    "$312": "vh",
    "$507": "vmax",
    "$313": "vmin",
    "$311": "vw",
    }


COLOR_YJ_PROPERTIES = {
    "$83", "$86", "$85", "$87", "$84", "$116",
    "$498", "$70", "$121", "$105", "$555", "$28", "$75",
    "$21", "$19", "$718", "$24",
    }

COLOR_NAME = {
    "#000000": "black",
    "#000080": "navy",
    "#0000ff": "blue",
    "#008000": "green",
    "#008080": "teal",
    "#00ff00": "lime",
    "#00ffff": "cyan",
    "#800000": "maroon",
    "#800080": "purple",
    "#808000": "olive",
    "#808080": "gray",
    "#ff0000": "red",
    "#ff00ff": "magenta",
    "#ffff00": "yellow",
    "#ffffff": "white",
    }

COLOR_NAMES = set(COLOR_NAME.values())

COLOR_HEX = {}
for h, n in COLOR_NAME.items():
    COLOR_HEX[n] = h


GENERIC_FONT_NAMES = {
    "serif", "sans-serif", "cursive", "fantasy", "monospace",

    "Arial", "Caecilia", "Courier", "Georgia", "Lucida", "Times New Roman", "Trebuchet",

    "Amazon Ember", "Amazon Ember Bold", "Baskerville", "Bookerly", "Caecilia",
    "Caecilia Condensed", "Futura", "Helvetica", "OpenDyslexic", "Palatino",

    "Helvetica Light", "Helvetica Neue LT", "Noto Sans",

    "明朝",
    "ゴシック",

    "Source Code Pro",

    "Droid Sans", "Droid Serif", "Verdana",

    "Book Antiqua", "Calibri", "Calibri Light", "Cambria", "Comic Sans MS", "Courier New", "Lucida Sans Unicode",
    "Palatino Linotype", "Tahoma", "Trebuchet MS",

    "CCL", "Helvetica Neue", "Malabar", "Merriweather", "Sorts Mill Goudy",

    "Code2000", "Palatino LT Std", "Times",

    "ＭＳ 明朝",
    "@ＭＳ 明朝",
    "MS Mincho",
    "@MS Mincho",

    "AmazonEmber Medium",
    "Bookerly Italic",
    "BookerlyDisplay Regular",
    }

DEFAULT_FONT_NAMES = {"default", "$amzn_fixup_default_font$"}


MISSPELLED_FONT_NAMES = {
    "san-serif": "sans-serif",
    "ariel": "Arial",
    }


KNOWN_STYLES = {
    "-amzn-float": {"bottom", "top", "top,bottom"},
    "-amzn-max-crop-percentage": {
            "0 0 0 0"},
    "-amzn-page-align": {
            "all", "bottom", "bottom,left", "bottom,left,right", "bottom,right", "left", "left,right",
            "right", "top", "top,bottom,left", "top,bottom,right", "top,left", "top,left,right", "top,right"},
    "-amzn-page-footer": {"disable"},
    "-amzn-page-header": {"disable"},
    "-amzn-shape-outside": {"*"},
    "-webkit-border-horizontal-spacing": {"0"},
    "-webkit-border-vertical-spacing": {"0"},
    "-webkit-box-decoration-break": {"clone", "slice"},
    "-webkit-hyphens": {"auto", "manual", "none"},
    "-webkit-line-break": {"anywhere", "auto", "loose", "normal", "strict"},
    "-webkit-ruby-position": {"over", "under"},
    "-webkit-text-combine": {"horizontal", "none"},
    "-webkit-text-emphasis-color": {"#0"},
    "-webkit-text-emphasis-position": {"over right", "under left"},
    "-webkit-text-emphasis-style": {
        "filled", "filled circle", "filled dot", "filled double-circle", "filled sesame", "filled triangle",
        "open", "open circle", "open dot", "open double-circle", "open sesame", "open triangle"},
    "-webkit-text-orientation": {"mixed", "sideways", "upright"},
    "-webkit-text-stroke-color": {"#0"},
    "-webkit-text-stroke-width": {"0"},
    "-webkit-transform": {"*"},
    "-webkit-transform-origin": {"0 0"},
    "-webkit-writing-mode": {"horizontal-tb", "vertical-lr", "vertical-rl"},
    "background-clip": {"border-box", "content-box", "padding-box"},
    "background-color": {"#0"},
    "background-image": {"*"},
    "background-origin": {"border-box", "content-box"},
    "background-position": {"0 0"},
    "background-size": {"0 0", "auto 0", "0 auto", "contain", "cover"},
    "background-repeat": {"no-repeat", "repeat-x", "repeat-y"},
    "border-bottom-color": {"#0"},
    "border-bottom-left-radius": {"0"},
    "border-bottom-right-radius": {"0"},
    "border-bottom-style": {"dashed", "dotted", "double", "groove", "inset", "none", "outset", "ridge", "solid"},
    "border-bottom-width": {"0"},
    "border-collapse": {"collapse", "separate"},
    "border-color": {"#0"},
    "border-left-color": {"#0"},
    "border-left-style": {"dashed", "dotted", "double", "groove", "inset", "none", "outset", "ridge", "solid"},
    "border-left-width": {"0"},
    "border-right-color": {"#0"},
    "border-right-style": {"dashed", "dotted", "double", "groove", "inset", "none", "outset", "ridge", "solid"},
    "border-right-width": {"0"},
    "border-spacing": {"0 0"},
    "border-style": {"dashed", "dotted", "double", "groove", "inset", "none", "outset", "ridge", "solid"},
    "border-top-color": {"#0"},
    "border-top-left-radius": {"0"},
    "border-top-right-radius": {"0"},
    "border-top-style": {"dashed", "dotted", "double", "groove", "inset", "none", "outset", "ridge", "solid"},
    "border-top-width": {"0"},
    "border-width": {"0"},
    "bottom": {"0"},
    "box-decoration-break": {"clone", "slice"},
    "box-shadow": {"0 0 #0", "0 0 #0 inset", "0 0 0 #0", "0 0 0 #0 inset", "0 0 0 0 #0", "0 0 0 0 #0 inset"},
    "box-sizing": {"border-box", "content-box"},
    "clear": {"both", "left", "none", "right"},
    "color": {"#0"},
    "column-count": {"0", "auto"},
    "direction": {"ltr", "rtl"},
    "display": {"block", "inline", "inline-block", "none", "oeb-page-foot", "oeb-page-head", "inline-table"},
    "float": {"left", "right", "snap-block"},
    "font-family": {"*"},
    "font-size": {"0"},
    "font-style": {"italic", "normal", "oblique"},
    "font-variant": {"normal", "small-caps"},
    "font-weight": {"0", "bold", "normal"},
    "height": {"0"},
    "hyphens": {"auto", "manual", "none"},
    "left": {"0"},
    "letter-spacing": {"0", "normal"},
    "line-break": {"anywhere", "auto", "loose", "normal", "strict"},
    "line-height": {"0", "normal"},
    "list-style-image": {"*"},
    "list-style-position": {"inside", "outside"},
    "list-style-type": {
        "circle", "cjk-ideographic", "decimal", "decimal-leading-zero", "disc", "georgian", "katakana", "katakana-iroha",
        "lower-alpha", "lower-armenian", "lower-greek", "lower-roman", "none", "square", "upper-alpha", "upper-armenian",
        "upper-greek", "upper-roman"},
    "margin": {"0"},
    "margin-bottom": {"0"},
    "margin-left": {"0", "auto"},
    "margin-right": {"0", "auto"},
    "margin-top": {"0"},
    "max-height": {"0"},
    "max-width": {"0"},
    "min-height": {"0"},
    "min-width": {"0"},
    "orphans": {"0"},
    "outline-color": {"#0"},
    "outline-offset": {"0"},
    "outline-style": {"dashed", "dotted", "double", "groove", "inset", "none", "outset", "ridge", "solid"},
    "outline-width": {"0"},
    "overflow": {"hidden"},
    "padding": {"0"},
    "padding-bottom": {"0"},
    "padding-left": {"0"},
    "padding-right": {"0"},
    "padding-top": {"0"},
    "page-break-after": {"always", "auto", "avoid"},
    "page-break-before": {"always", "auto", "avoid"},
    "page-break-inside": {"auto", "avoid"},
    "position": {"absolute", "fixed", "relative"},
    "right": {"0"},
    "ruby-align": {"center", "space-around", "space-between", "start"},
    "ruby-position": {"over", "under"},
    "src": {"*"},
    "text-align": {"center", "justify", "left", "right"},
    "text-align-last": {"auto", "center", "end", "justify", "left", "right", "start"},
    "text-combine-upright": {"all", "none"},
    "text-decoration": {
            "line-through", "none !important", "overline", "underline",
            "overline dashed", "overline dotted", "overline double",
            "underline dashed", "underline dotted", "underline double",
            "line-through dashed", "line-through dotted", "line-through double",
            "overline underline", "line-through overline", "line-through underline",
            "line-through overline underline"},
    "text-decoration-color": {"#0"},
    "text-emphasis-color": {"#0"},
    "text-emphasis-position": {"over right", "under left"},
    "text-emphasis-style": {
        "filled", "filled circle", "filled dot", "filled double-circle", "filled sesame", "filled triangle",
        "open", "open circle", "open dot", "open double-circle", "open sesame", "open triangle"},
    "text-indent": {"0"},
    "text-orientation": {"mixed", "sideways", "upright"},
    "text-shadow": {"*"},
    "text-transform": {"capitalize", "none", "lowercase", "uppercase"},
    "top": {"0"},
    "transform": {"*"},
    "transform-origin": {"0 0"},
    "unicode-bidi": {"bidi-override", "embed", "isolate", "isolate-override", "normal", "plaintext"},
    "vertical-align": {"0", "baseline", "bottom", "middle", "sub", "super", "text-bottom", "text-top", "top"},
    "visibility": {"hidden", "visible"},
    "white-space": {"normal", "nowrap"},
    "widows": {"0"},
    "width": {"0"},
    "word-break": {"break-all", "normal"},
    "word-spacing": {"0", "normal"},
    "writing-mode": {"horizontal-tb", "vertical-lr", "vertical-rl"},
    "z-index": {"0"},
    }


ARBITRARY_VALUE_PROPERTIES = {
    "-amzn-shape-outside", "-kfx-attrib-xml-lang", "-kfx-layout-hints", "-kfx-style-name",
    "background-image", "font-family", "list-style-image", "src",
    }


COMPOSITE_SIDE_STYLES = [
    ["border-color", ["border-bottom-color", "border-left-color", "border-right-color", "border-top-color"]],
    ["border-style", ["border-bottom-style", "border-left-style", "border-right-style", "border-top-style"]],
    ["border-width", ["border-bottom-width", "border-left-width", "border-right-width", "border-top-width"]],
    ["margin", ["margin-bottom", "margin-left", "margin-right", "margin-top"]],
    ["padding", ["padding-bottom", "padding-left", "padding-right", "padding-top"]],
    ]

CONFLICTING_PROPERTIES = {
    "background": {
        "background-attachment", "background-clip", "background-color", "background-image",
        "background-origin", "background-position", "background-repeat", "background-size"},
    "border-color": {"border-bottom-color", "border-left-color", "border-right-color", "border-top-color"},
    "border-style": {"border-bottom-style", "border-left-style", "border-right-style", "border-top-style"},
    "border-width": {"border-bottom-width", "border-left-width", "border-right-width", "border-top-width"},
    "font": {"font-family", "font-size", "font-style", "font-variant", "font-weight"},
    "list-style": {"list-style-type", "list-style-position", "list-style-image"},
    "margin": {"margin-bottom", "margin-left", "margin-right", "margin-top"},
    "outline": {"outline-width", "outline-style", "outline-color"},
    "padding": {"padding-bottom", "padding-left", "padding-right", "padding-top"},
    }

for name, conf_set in list(CONFLICTING_PROPERTIES.items()):
    for conf in conf_set:
        if conf not in CONFLICTING_PROPERTIES:
            CONFLICTING_PROPERTIES[conf] = set()

        CONFLICTING_PROPERTIES[conf].add(name)


ALTERNATE_EQUIVALENT_PROPERTIES = {
    "box-decoration-break": "-webkit-box-decoration-break",
    "hyphens": "-webkit-hyphens",
    "line-break": "-webkit-line-break",
    "ruby-position": "-webkit-ruby-position",
    "text-combine-upright": "-webkit-text-combine",
    "text-emphasis-color": "-webkit-text-emphasis-color",
    "text-emphasis-position": "-webkit-text-emphasis-position",
    "text-emphasis-style": "-webkit-text-emphasis-style",
    "text-orientation": "-webkit-text-orientation",
    "transform": "-webkit-transform",
    "transform-origin": "-webkit-transform-origin",
    "writing-mode": "-webkit-writing-mode",
    }


HERITABLE_DEFAULT_PROPERTIES = {
    "-amzn-page-align": "none",
    "-kfx-attrib-xml-lang": None,
    "-kfx-link-color": None,
    "-kfx-user-margin-bottom-percentage": "100",
    "-kfx-user-margin-left-percentage": "100",
    "-kfx-user-margin-right-percentage": "100",
    "-kfx-user-margin-top-percentage": "100",
    "-kfx-visited-color": None,
    "-webkit-border-horizontal-spacing": "2px",
    "-webkit-border-vertical-spacing": "2px",
    "-webkit-text-stroke-color": None,
    "-webkit-text-stroke-width": "0",
    "border-collapse": "separate",
    "border-spacing": "2px 2px",
    "caption-side": "top",
    "color": None,
    "cursor": "auto",
    "direction": "ltr",
    "empty-cells": "show",
    "font": None,
    "font-family": DEFAULT_DOCUMENT_FONT_FAMILY,
    "font-feature-settings": None,
    "font-language-override": "normal",
    "font-kerning": "auto",
    "font-size": "1rem",
    "font-size-adjust": "none",
    "font-stretch": "normal",
    "font-style": "normal",
    "font-synthesis": "weight style",
    "font-variant": "normal",
    "font-weight": "normal",
    "hanging-punctuation": "none",
    "hyphens": None,
    "letter-spacing": "normal",
    "line-break": "auto",
    "line-height": "normal",
    "list-style": None,
    "list-style-image": "none",
    "list-style-position": "outside",
    "list-style-type": "disc",
    "orphans": "2",
    "overflow-wrap": "normal",
    "quotes": None,
    "ruby-align": "space-around",
    "ruby-merge": "separate",
    "ruby-position": "over",
    "tab-size": "8",
    "text-align": None,
    "text-align-last": "auto",
    "text-combine-upright": "none",
    "text-justify": "auto",
    "text-shadow": "none",
    "text-transform": "none",
    "text-indent": "0",
    "text-orientation": "mixed",
    "text-underline-position": "auto",
    "unicode-bidi": "normal",
    "visibility": "visible",
    "white-space": "normal",
    "widows": "2",
    "word-break": "normal",
    "word-spacing": "normal",
    "word-wrap": "normal",
    "writing-mode": "horizontal-tb",
    }

HERITABLE_PROPERTIES = set(HERITABLE_DEFAULT_PROPERTIES.keys())
HERITABLE_DEFAULTS_FILTERED = dict([(k, v) for k, v in HERITABLE_DEFAULT_PROPERTIES.items() if v is not None])


REVERSE_HERITABLE_PROPERTIES = HERITABLE_PROPERTIES - {
    "-amzn-page-align",
    "-kfx-user-margin-bottom-percentage",
    "-kfx-user-margin-left-percentage",
    "-kfx-user-margin-right-percentage",
    "-kfx-user-margin-top-percentage",
    "font-size",
    "line-height",
    }

NON_HERITABLE_DEFAULT_PROPERTIES = {
    "background-clip": "border-box",
    "background-color": "transparent",
    "background-image": "none",
    "background-origin": "padding-box",
    "background-position": "0% 0%",
    "background-repeat": "repeat",
    "background-size": "auto auto",
    "box-sizing": "content-box",
    "box-decoration-break": "slice",
    "column-count": "auto",
    "float": "none",
    "margin-bottom": "0",
    "margin-left": "0",
    "margin-right": "0",
    "margin-top": "0",
    "overflow": "visible",
    "padding-bottom": "0",
    "padding-left": "0",
    "padding-right": "0",
    "padding-top": "0",
    "page-break-after": "auto",
    "page-break-before": "auto",
    "page-break-inside": "auto",
    "position": "static",
    "text-decoration": "none",
    "text-emphasis-position": "over right",
    "transform": "none",
    "transform-origin": "50% 50% 0",
    "vertical-align": "baseline",
    "z-index": "auto",
    }


RESET_CSS_DATA = (
    "html {color: #000; background: #FFF;}\n" +
    "body,div,dl,dt,dd,ul,ol,li,h1,h2,h3,h4,h5,h6,th,td {margin: 0; padding: 0;}\n" +
    "table {border-collapse: collapse; border-spacing: 0;}\n" +
    "fieldset,img {border: 0;}\n" +
    "caption,th,var {font-style: normal; font-weight: normal;}\n" +
    "li {list-style: none;}\n" +
    "caption,th {text-align: left;}\n" +
    "h1,h2,h3,h4,h5,h6 {font-size: 100%; font-weight: normal;}\n" +
    "sup {vertical-align: text-top;}\n" +
    "sub {vertical-align: text-bottom;}\n" +
    "a.app-amzn-magnify {display: block; width: 100%; height: 100%;}\n")


AMAZON_SPECIAL_CLASSES = [
    "app-amzn-magnify",
    ]


INLINE_ELEMENTS = {"a", "bdo", "br", "img", "object", "rp", "ruby", "span"}


style_cache = {}


class KFX_EPUB_Properties(object):
    def __init__(self):
        self.css_rules = {}
        self.missing_special_classes = set()
        self.media_queries = collections.defaultdict(dict)
        self.present_font_names = set()
        self.used_font_names = set()
        self.font_name_replacements = {}
        self.fixed_font_names = {}
        self.font_faces = []
        self.incorrect_font_quoting = set()

        for name in GENERIC_FONT_NAMES:
            self.fix_font_name(name, add=True, generic=True)

    def Style(self, x):
        return Style(x)

    def process_content_properties(self, content):
        content_properties = {}
        for property_name in list(content.keys()):
            if property_name in YJ_PROPERTY_NAMES:
                content_properties[property_name] = content.pop(property_name)

        return self.convert_yj_properties(content_properties)

    def convert_yj_properties(self, yj_properties):
        declarations = {}

        for yj_property_name, yj_value in yj_properties.items():
            value = self.property_value(yj_property_name, yj_value)

            if yj_property_name in YJ_PROPERTY_INFO:
                property = YJ_PROPERTY_INFO[yj_property_name].name
            else:
                log.warning("unknown property name: %s" % yj_property_name)
                property = str(yj_property_name).replace("_", "-")

            if property == "position" and value in ["oeb-page-foot", "oeb-page-head"]:
                property = "display" if self.generate_epub2 and EMIT_OEB_PAGE_PROPS else None

            if (property is not None) and (value is not None):
                decl_value = declarations.get(property)
                if decl_value is not None and decl_value != value:
                    if property == "-kfx-attrib-epub-type":
                        vals = set(decl_value.split() + value.split())
                        for val in vals:
                            if not val.startswith("amzn:"):
                                log.error("Property %s has multiple incompatible values: \"%s\" and \"%s\"" % (
                                    property, decl_value, value))
                                break
                        else:
                            value = " ".join(sorted(list(vals)))

                    elif property == "text-decoration":
                        vals = set(decl_value.split() + value.split())
                        value = " ".join(sorted(list(vals)))

                    else:
                        log.error("Property %s has multiple values: \"%s\" and \"%s\"" % (property, decl_value, value))

                declarations[property] = value

        if declarations.get("text-combine-upright") == "all":
            self.text_combine_in_use = True
            if declarations.get("writing-mode") == "horizontal-tb":
                declarations.pop("writing-mode")

        if "-kfx-background-positionx" in declarations or "-kfx-background-positiony" in declarations:
            declarations["background-position"] = "%s %s" % (
                    declarations.pop("-kfx-background-positionx", "50%"), declarations.pop("-kfx-background-positiony", "50%"))

        if "-kfx-background-sizex" in declarations or "-kfx-background-sizey" in declarations:
            declarations["background-size"] = "%s %s" % (
                    declarations.pop("-kfx-background-sizex", "auto"), declarations.pop("-kfx-background-sizey", "auto"))

        if "-kfx-fill-color" in declarations or "-kfx-fill-opacity" in declarations:
            declarations["background-color"] = self.add_color_opacity(
                    declarations.pop("-kfx-fill-color", "#ffffff"),
                    declarations.pop("-kfx-fill-opacity", None))

        if "-kfx-text-emphasis-position-horizontal" in declarations or "-kfx-text-emphasis-position-vertical" in declarations:
            declarations["text-emphasis-position"] = " ".join(
                    [v for v in [declarations.pop("-kfx-text-emphasis-position-horizontal", None),
                                 declarations.pop("-kfx-text-emphasis-position-vertical", None)] if v])

        if "-kfx-keep-lines-together" in declarations:
            for prop, val in zip(["orphans", "widows"], declarations.pop("-kfx-keep-lines-together").split()):
                if val != "inherit":
                    declarations[prop] = val

        if ("text-decoration-color" in declarations and "text-decoration" not in declarations and
                declarations["text-decoration-color"] == "rgba(255,255,255,0)"):
            declarations.pop("text-decoration-color")
            declarations["text-decoration"] = "none !important"

        if FIX_NONSTANDARD_FONT_WEIGHT and "font-weight" in declarations and re.match(r"^[0-9]+$", declarations["font-weight"]):
            weight_num = int(declarations["font-weight"])
            declarations["font-weight"] = "normal" if weight_num <= 500 else "bold"

        for combined_prop, individual_props in COMPOSITE_SIDE_STYLES:
            val = declarations.get(combined_prop, None)
            if val is not None:
                for individual_prop in individual_props:
                    if individual_prop not in declarations:
                        declarations[individual_prop] = val

                declarations.pop(combined_prop)

        return self.Style(declarations)

    def property_value(self, yj_property_name, yj_value, svg=False):
        property_info = YJ_PROPERTY_INFO.get(yj_property_name, None)
        value_map = property_info.values if property_info is not None else None

        val_type = ion_type(yj_value)

        if val_type is IonStruct:
            if "$307" in yj_value:
                magnitude = yj_value.pop("$307")
                unit = yj_value.pop("$306")
                if unit not in YJ_LENGTH_UNITS:
                    log.error("Property %s has unknown unit: %s" % (yj_property_name, unit))

                if DETECT_LAYOUT_ENHANCER and yj_property_name == "$65" and unit == "$318" and magnitude in [216, 270, 324, 360]:
                    log.warning("YJImageLayoutEnhancer detected, max_width=%s" % value_str(magnitude, YJ_LENGTH_UNITS.get(unit, unit)))

                if FIX_PT_TO_PX and unit == "$318" and magnitude > 0:
                    if int(magnitude * 1000) % 225 == 0:
                        px_value = int(magnitude * 1000) / 450.0
                        magnitude = px_value
                        unit = "$319"

                if unit == "$319":
                    magnitude = self.adjust_pixel_value(magnitude)

                value = value_str(magnitude, YJ_LENGTH_UNITS.get(unit, unit))

                if USE_NORMAL_LINE_HEIGHT and yj_property_name == "$42" and value == NORMAL_LINE_HEIGHT_EM:
                    value = "normal"

            elif "$19" in yj_value:
                value = self.fix_color_value(yj_value.pop("$19"))

            elif "$499" in yj_value and "$500" in yj_value:
                values = []
                for sub_property in ["$499", "$500", "$501", "$502", "$498"]:
                    if sub_property in yj_value:
                        values.append(self.property_value(sub_property, yj_value.pop(sub_property)))

                if yj_value.pop("$336", False):
                    values.append("inset")

                value = " ".join(values)

            elif "$58" in yj_value and yj_property_name == "$549":
                values = []
                for sub_property in ["$59", "$58"]:
                    if sub_property in yj_value:
                        values.append(self.property_value(sub_property, yj_value.pop(sub_property)))
                    else:
                        log.error("Missing sub-property %s for %s" % (sub_property, yj_property_name))
                        values.append("50%")

                value = " ".join(values)

            elif "$58" in yj_value:
                values = []
                for sub_property in ["$58", "$61", "$60", "$59"]:
                    if sub_property in yj_value:
                        val = self.property_value(sub_property, yj_value.pop(sub_property))
                        if val != "0" and not val.endswith("%"):
                            log.error("Property %s has unexpected value: %s" % (yj_property_name, val))
                        values.append(val.replace("%", ""))
                    else:
                        log.error("Missing sub-property %s for %s" % (sub_property, yj_property_name))

                value = " ".join(values)

            elif "$175" in yj_value:
                yj_value.pop("$57", None)
                yj_value.pop("$56", None)
                value = self.property_value("$175", yj_value.pop("$175"))

            elif "$131" in yj_value or "$132" in yj_value:
                value = "%s %s" % (yj_value.pop("$131", "inherit"), yj_value.pop("$132", "inherit"))

            else:
                log.error("Property %s has unknown dict value content: %s" % (yj_property_name, repr(yj_value)))
                yj_value = {}
                value = "?"

            self.check_empty(yj_value, "Property %s value" % yj_property_name)

        elif val_type is IonString:
            if yj_property_name == "$11":
                value = self.fix_and_quote_font_family_list(yj_value)
            elif yj_property_name == "$10":
                value = self.fix_language(yj_value)
            else:
                value = yj_value

        elif val_type is IonSymbol:
            if yj_property_name == "$173":
                value = self.unique_part_of_local_symbol(yj_value)
                if not value:
                    value = None

            elif yj_property_name in {"$479", "$175", "$528"}:
                value = self.css_url(urlrelpath(
                        self.process_external_resource(yj_value).filename, ref_from=self.STYLES_CSS_FILEPATH))

            elif yj_property_name in COLOR_YJ_PROPERTIES:
                if yj_value == "$349":
                    value = self.fix_color_value(0)
                else:
                    log.warning("unexpected symbolic property value for %s: %s" % (yj_property_name, yj_value))

            else:
                if value_map is not None:
                    if yj_value in value_map:
                        value = value_map[yj_value]
                    else:
                        log.warning("unknown property value for %s: %s" % (yj_property_name, yj_value))
                        value = str(yj_value)
                else:
                    log.warning("unexpected symbolic property value for %s: %s" % (yj_property_name, yj_value))
                    value = str(yj_value)

                if yj_property_name == "$11":
                    value = self.fix_and_quote_font_family_list(value)

        elif val_type in [IonInt, IonFloat, IonDecimal]:
            value = value_str(yj_value)

            if yj_property_name in COLOR_YJ_PROPERTIES:
                if yj_property_name == "$70" and int(yj_value) & ALPHA_MASK == 0:
                    value = int(yj_value) | ALPHA_MASK

                value = self.fix_color_value(value)

            elif value != "0" and yj_property_name not in {
                    "$112", "$13",
                    "$148", "$149", "$645", "$647",
                    "$648", "$790", "$640",
                    "$641", "$642",
                    "$639", "$72",
                    "$126", "$125", "$42"} and not svg:

                value = value_str(self.adjust_pixel_value(yj_value))

                value += "px"

            else:
                value = value_str(yj_value)

        elif val_type is IonBool:
            if value_map is not None:
                if yj_value in value_map:
                    value = value_map[yj_value]
                else:
                    log.warning("unknown property value for %s: %s" % (yj_property_name, yj_value))
                    value = str(yj_value)
            else:
                log.warning("unexpected boolean property value for %s: %s" % (yj_property_name, yj_value))
                value = str(yj_value)

        elif val_type is IonList:
            if yj_property_name == "$650":
                value = self.process_polygon(yj_value)

            elif yj_property_name == "$646" and len(yj_value) > 0:
                values = []
                for collision in yj_value:
                    if collision in COLLISIONS:
                        values.append(COLLISIONS[collision])
                    else:
                        log.error("Unexpected yj.collision value: %s" % str(collision))

                value = " ".join(sorted(values))

            elif yj_property_name == "$98":
                value = self.process_transform(yj_value, svg)

            elif yj_property_name == "$497":
                values = []
                for text_shadow in yj_value:
                    values.append(self.property_value(yj_property_name, text_shadow))

                value = ", ".join(values)

            elif yj_property_name == "$761":
                values = []
                for layout_hint in yj_value:
                    element_name = LAYOUT_HINT_ELEMENT_NAMES.get(layout_hint)
                    if element_name:
                        values.append(element_name)
                    else:
                        log.warning("Unexpected layout_hint %s" % layout_hint)

                value = " ".join(values)

            elif yj_property_name == "$531":
                value = " ".join([self.property_value(yj_property_name, val_) for val_ in yj_value])

            else:
                log.error("unexpected IonList property value for %s: %s" % (yj_property_name, yj_value))
                value = "?"

        else:
            log.error("Property %s has unknown value format (%s): %s" % (
                            yj_property_name, type_name(yj_value), repr(yj_value)))
            value = "?"

        if (yj_property_name in {
                "$640", "$641",
                "$642", "$639"} and
                value not in ["100", "-100"]):
            log.error("Property %s has disallowed value: %s" % (yj_property_name, value))

        if yj_property_name in {"$32", "$33"} and value == "0em":
            value = "normal"

        return value

    def fixup_styles_and_classes(self):
        if STYLE_TEST:
            log.warning("Style simplification disabled")
            return

        self.css_rules = {}

        self.non_heritable_default_properties = self.Style(NON_HERITABLE_DEFAULT_PROPERTIES)

        for book_part in self.book_parts:
            self.last_kfx_heading_level = "1"
            heritable_default_properties = self.Style(HERITABLE_DEFAULTS_FILTERED)
            lang = book_part.html.get(XML_LANG)
            if lang:
                heritable_default_properties.update(self.Style({"-kfx-attrib-xml-lang": lang}), replace=True)

            self.simplify_styles(book_part.body(), book_part, heritable_default_properties)

            self.add_composite_and_equivalent_styles(book_part.body(), book_part)

        self.create_conditional_page_templates()

        style_counts = collections.defaultdict(lambda: 0)

        for book_part in self.book_parts:
            body = book_part.body()
            for e in body.iter("*"):
                class_name = e.get("class")
                if class_name and (class_name not in AMAZON_SPECIAL_CLASSES):
                    selector = class_selector(class_name)
                    if selector not in self.missing_special_classes:
                        log.error("Unexpected class found: %s" % class_name)
                        self.missing_special_classes.add(selector)

                if "style" in e.attrib:

                    style = self.get_style(e)
                    style_modified = False

                    style_attribs = style.partition(name_prefix="-kfx-attrib-", remove_prefix=True)
                    if style_attribs:
                        style_modified = True
                        for name, value in style_attribs.items():
                            if name.startswith("epub-"):
                                name = qname(EPUB_NS_URI, name.partition("-")[2])
                                if name == EPUB_TYPE:
                                    if self.generate_epub2:
                                        continue

                            elif name.startswith("xml-"):
                                name = qname(XML_NS_URI, name.partition("-")[2])

                            if name in ["colspan", "rowspan", "valign"] and e.tag not in ["tbody", "tr", "td"]:
                                log.error("Unexpected class_attribute in %s: %s" % (e.tag, name))

                            e.set(name, value)

                    if style_modified:
                        self.set_style(e, style)

                    if (CVT_DIRECTION_PROPERTY_TO_MARKUP or not self.generate_epub2) and ("direction" in style or "unicode-bidi" in style):
                        unicode_bidi = style.get("unicode-bidi", "normal")

                        has_block = False
                        has_content = e.text
                        for ex in e.iterfind(".//*"):
                            if ex.tag in {
                                    "aside", "div", "figure", "h1", "h2", "h3", "h4", "h5", "h6", "iframe", "li",
                                    "ol", "p", "table", "td", "ul"}:
                                has_block = True

                            if ex.text or ex.tail or ex.tag in {"audio", "img", "li", MATH, "object", SVG, "video"}:
                                has_content = True

                            if has_block and has_content:
                                break

                        if not has_content:
                            style.pop("direction", None)
                            style.pop("unicode-bidi", None)
                            self.set_style(e, style)

                        elif unicode_bidi in ["embed", "normal"] or has_block:
                            if "direction" in style:
                                e.set("dir", style.pop("direction"))

                            style.pop("unicode-bidi", None)
                            self.set_style(e, style)

                        elif unicode_bidi in ["isolate", "bidi-override", "isolate-override"]:

                            bdx = etree.Element("bdo" if "override" in unicode_bidi else "bdi")
                            if "direction" in style:
                                bdx.set("dir", style.pop("direction"))

                            if e.tag != "img":
                                bdx.text = e.text
                                e.text = None

                                while len(e) > 0:
                                    ec = e[0]
                                    e.remove(ec)
                                    bdx.append(ec)

                                e.insert(0, bdx)

                            style.pop("unicode-bidi", None)
                            self.set_style(e, style)

                        else:
                            log.error("Cannot produce EPUB3 equivalent for: unicode-bidi:%s direction:%s" % (
                                    unicode_bidi, style.get("direction", "?")))

                    if REMOVE_EMPTY_NAMED_CLASSES and len(style.partition({"-kfx-style-name", "-kfx-layout-hints"}, keep_all=True)) == 0:
                        style.pop("-kfx-style-name", None)
                        style.pop("-kfx-layout-hints", None)
                        self.set_style(e, style)

                if "style" in e.attrib:
                    style_counts[e.get("style")] += 1

        sorted_style_data = []
        known_class_name_count = collections.defaultdict(lambda: 0)

        for class_name in AMAZON_SPECIAL_CLASSES:
            known_class_name_count[class_name] = 2

        for style_str, count in sorted(style_counts.items(), key=lambda sc: -sc[1]):
            style = self.Style(style_str)

            class_name = re.sub(r"[^A-Za-z0-9_-]", "_", style.pop("-kfx-style-name", ""))

            if "-kfx-layout-hints" in style:
                class_name_prefix = "-".join(sorted(list(style.pop("-kfx-layout-hints").split())))
            else:
                class_name_prefix = DEFAULT_CLASS_NAME_PREFIX

            known_class_name_count[class_name_prefix] += 1

            class_name = self.prefix_unique_part_of_symbol(class_name, class_name_prefix)
            known_class_name_count[class_name] += 1
            sorted_style_data.append((style_str, style, class_name))

        classes = {}
        style_class_names = {}
        used_class_name_count = collections.defaultdict(lambda: 0)
        referenced_classes = set()
        selector_classes = set()

        for style_str, style, class_name in sorted_style_data:
            if known_class_name_count[class_name] > 1 or class_name in classes:
                while True:
                    unique = used_class_name_count[class_name]
                    used_class_name_count[class_name] += 1
                    class_name = "%s-%d" % (class_name, unique)
                    if known_class_name_count[class_name] == 0 and class_name not in classes:
                        break

            for prop_name_prefix, selector_suffix in [
                        ("-kfx-firstline-", "::first-line"),
                        ("-kfx-link-", ":link"),
                        ("-kfx-visited-", ":visited")]:

                selector_style = style.partition(name_prefix=prop_name_prefix, remove_prefix=True)
                if selector_style:
                    self.css_rules[class_selector(class_name) + selector_suffix] = selector_style
                    selector_classes.add(class_name)

            classes[class_name] = style
            style_class_names[style_str] = class_name

        for book_part in self.book_parts:
            body = book_part.body()
            for e in body.iter("*"):
                style_str = e.get("style", "")
                if style_str in style_class_names:
                    class_name = style_class_names[style_str]
                    class_style = classes[class_name]

                    if ((KEEP_STYLES_INLINE or book_part.is_fxl) and
                            class_name not in selector_classes and
                            "-kfx-media-query" not in class_style):
                        e.set("style", class_style.tostring())
                        self.inventory_style(class_style)
                    else:
                        self.add_class(e, class_name, before=True)
                        referenced_classes.add(class_name)
                        e.attrib.pop("style", None)

                elif style_str:
                    log.warning("Style has no class name: %s" % style_str)

        for class_name, class_style in classes.items():
            if class_name in referenced_classes:
                media_query = class_style.pop("-kfx-media-query")
                if class_style:
                    target = self.media_queries[media_query] if media_query else self.css_rules
                    target[class_selector(class_name)] = class_style

        for class_style in list(self.css_rules.values()) + self.font_faces:
            self.inventory_style(class_style)

        for mq_classes in self.media_queries.values():
            for class_style in mq_classes.values():
                self.inventory_style(class_style)

    def inventory_style(self, style):
        reported = set()
        for key, value in style.items():
            simple_value = " ".join(zero_quantity(v) for v in value.split())
            if ((simple_value not in KNOWN_STYLES.get(key, set())) and ("*" not in KNOWN_STYLES.get(key, set())) and
                    (key, value) not in reported):
                log.error("Unexpected style definition: %s: %s" % (key, value))

                reported.add((key, value))

    def update_default_font_and_language(self):

        content_font_families = collections.defaultdict(lambda: 0)
        content_languages = collections.defaultdict(lambda: 0)

        def scan_content(elem, font_family, lang):

            style = elem.get("style", "")
            if "font-family" in style or "-kfx-attrib-xml-lang" in style:
                sty = self.Style(style)
                font_family = sty.get("font-family", font_family)
                lang = sty.get("-kfx-attrib-xml-lang", lang)

            text_len = len(elem.text or "")

            for e in elem.iterfind("*"):
                if e.tag != "head":
                    text_len += scan_content(e, font_family, lang)

            if text_len:
                content_font_families[font_family] += text_len
                content_languages[lang] += text_len

            return len(elem.tail or "")

        for book_part in self.book_parts:
            scan_content(book_part.html, None, None)

        best_font_family, best_merit = self.default_font_family, 0
        default_font_family_pattern = re.compile(re.escape(self.default_font_family) + "(,.+)?$")

        for font_family, merit in content_font_families.items():
            if merit > best_merit and font_family and re.match(default_font_family_pattern, font_family):
                best_font_family, best_merit = font_family, merit

        self.default_font_family = best_font_family

        best_language, best_merit = self.language, 0

        if self.language:
            default_language_pattern = re.compile(re.escape(self.language) + "(-.+)?$", re.IGNORECASE)

            for language, merit in content_languages.items():
                if merit > best_merit and language and re.match(default_language_pattern, language):
                    best_language, best_merit = language, merit

            self.language = best_language

    def set_html_defaults(self):
        for book_part in self.book_parts:
            if not book_part.is_cover_page:
                body = book_part.body()
                body_sty = self.get_style(body)

                if "font-family" not in body_sty and self.default_font_family:
                    body_sty["font-family"] = self.default_font_family

                if "font-size" not in body_sty:
                    body_sty["font-size"] = self.default_font_size

                if "line-height" not in body_sty:
                    body_sty["line-height"] = self.default_line_height

                if "writing-mode" not in body_sty:
                    body_sty["writing-mode"] = self.writing_mode

                self.set_style(body, body_sty)

                if self.language:
                    book_part.html.set(XML_LANG, self.language)

    def simplify_styles(self, elem, book_part, inherited_properties, default_ordered_list_value=None, known_width=True):
        inherited_properties = inherited_properties.copy()

        if split_value(inherited_properties.get("font-size", ""))[1] == "em":
            inherited_properties["font-size"] = "1em"

        sty = inherited_properties.copy().update(self.get_style(elem), replace=True)
        orig_sty = sty.copy()

        sty.pop("-kfx-render", None)

        if (book_part.is_fxl and elem.tag in {"a", "span"} and sty.get("display", "inline") == "inline" and
                ("height" in sty or "width" in sty)):
            sty["display"] = "inline-block"

        if sty.get("position", "static") == "static":
            for positioning in ["top", "bottom", "left", "right"]:
                if positioning in sty:
                    if sty[positioning] == "0":
                        sty.pop(positioning)
                    else:
                        log.warning("%s style with unexpected position: %s" % (elem.tag, sty.tostring()))

        sty["border-spacing"] = "%s %s" % (sty["-webkit-border-horizontal-spacing"], sty["-webkit-border-vertical-spacing"])

        sides = []
        for s in ["top", "bottom", "left", "right"]:
            if sty.pop("-kfx-user-margin-%s-percentage" % s, "100") == "-100":
                sides.append(s)

        page_align = sty["-amzn-page-align"] = (",".join(sides) if len(sides) < 4 else "all") if len(sides) > 0 else "none"

        for name, val in list(sty.items()):
            if name in {"padding", "padding-top", "padding-bottom", "padding-left", "padding-right"} and val.startswith("-"):
                log.warning("Discarding invalid %s: %s" % (name, val))
                sty.pop(name)

            elif name not in ARBITRARY_VALUE_PROPERTIES:
                quantity, unit = split_value(val)

                if unit == "lh" and quantity is not None:
                    if name == "line-height":
                        if USE_NORMAL_LINE_HEIGHT and quantity >= 0.99 and quantity <= 1.01:
                            sty[name] = "normal"
                        else:
                            quantity = quantity * LINE_HEIGHT_SCALE_FACTOR

                            if (MINIMUM_LINE_HEIGHT is not None) and (quantity < MINIMUM_LINE_HEIGHT):
                                quantity = MINIMUM_LINE_HEIGHT

                            sty[name] = value_str(quantity)
                    else:
                        sty[name] = value_str(quantity * LINE_HEIGHT_SCALE_FACTOR, "em")

                    quantity, unit = split_value(sty[name])

                if unit == "rem" and quantity is not None and (self.generate_epub2 or self.GENERATE_EPUB2_COMPATIBLE):
                    if name == "font-size":
                        base_font_size = inherited_properties["font-size"]
                    else:
                        base_font_size = orig_sty["font-size"]

                    base_font_size_quantity, base_font_size_unit = split_value(base_font_size)

                    if base_font_size_unit == "rem":
                        quantity = quantity / base_font_size_quantity
                        unit = "em"
                    elif base_font_size_unit == "em":
                        unit = "em"
                    else:
                        log.error("Cannot convert %s:%s with incorrect base font size units %s" % (name, val, base_font_size))

                    if name == "line-height" and (MINIMUM_LINE_HEIGHT is not None) and (quantity < MINIMUM_LINE_HEIGHT):
                        quantity = MINIMUM_LINE_HEIGHT

                    sty[name] = value_str(quantity, unit)

                if (unit == "vh" or unit == "vw") and quantity is not None:

                    if page_align != "none" and name in ["height", "width"]:
                        if name[0] != unit[1]:
                            if not ("height" in sty and "width" in sty):
                                if elem.tag == "img":
                                    img_filename = get_url_filename(urlabspath(elem.get("src"), ref_from=book_part.filename))
                                    img_file = self.oebps_files[img_filename]
                                    orig_prop = name
                                    sty.pop(orig_prop)

                                    if name == "width":
                                        quantity = (quantity * img_file.height) / img_file.width
                                        name = "height"
                                    else:
                                        quantity = (quantity * img_file.width) / img_file.height
                                        name = "width"

                                    if quantity > 99.0 and quantity < 101.0:
                                        quantity = 100.0
                                    else:
                                        log.warning("converted %s:%s for img %dw x %dh to %s:%f%%" % (
                                                orig_prop, val, img_file.width, img_file.height, name, quantity))

                                else:
                                    log.error("viewport-based units with wrong property on non-image: %s:%s" % (name, val))
                            else:
                                log.error("viewport-based units with wrong property: %s:%s" % (name, val))

                        sty[name] = value_str(quantity, "%")
                        quantity, unit = split_value(sty[name])
                    else:
                        log.error("viewport-based units with wrong property or without page-align: %s:%s" % (name, val))

        if "width" in sty:
            known_width = True
        elif sty.get("display", "") == "inline-block":
            known_width = False

        if not known_width:
            for name in (["margin-left", "margin-right"] if sty.get("writing-mode", "horizontal-tb") == "horizontal-tb" else
                         ["margin-bottom", "margin-top"]):
                if name in sty:
                    val = sty.get(name)
                    quantity, unit = split_value(val)
                    if unit == "%" and quantity is not None:
                        sty[name] = value_str(round(float(quantity) * PX_PER_PERCENT), "px")

        if ("outline-width" in sty) and (sty.get("outline-style", "none") == "none"):
            sty.pop("outline-width")

        if elem.tag == "ol":
            if "start" in elem.attrib:
                default_ordered_list_value = int(elem.get("start"))
                if default_ordered_list_value == 1:
                    elem.attrib.pop("start")
            else:
                default_ordered_list_value = 1

        elif elem.tag == "ul":
            if "start" in elem.attrib:
                elem.attrib.pop("start")

            default_ordered_list_value = False

        elif elem.tag == "li":
            if "value" in elem.attrib:
                ordered_list_value = int(elem.get("value"))
                if (default_ordered_list_value is False) or (ordered_list_value == default_ordered_list_value):
                    elem.attrib.pop("value")

            default_ordered_list_value = None

        else:
            default_ordered_list_value = None

        if elem.tag == "div":
            sty.update(self.non_heritable_default_properties, replace=False)

        if sty.get("background-image", "none") != "none" and "-amzn-max-crop-percentage" in sty:
            if sty["-amzn-max-crop-percentage"] == "0 0 0 0":
                sty.pop("-amzn-max-crop-percentage")
                sty["background-size"] = "contain"
            elif sty["-amzn-max-crop-percentage"] == "0 100 100 0":
                sty.pop("-amzn-max-crop-percentage")
                sty["background-size"] = "cover"

        if (elem.tag == "a" and "color" not in sty and "-kfx-link-color" in sty and "-kfx-visited-color" in sty and
                sty["-kfx-link-color"] == sty["-kfx-visited-color"]):
            sty["color"] = sty.pop("-kfx-link-color")
            sty.pop("-kfx-visited-color")

        parent_sty = sty.copy()

        for name in ["font-size", "-kfx-user-margin-bottom-percentage", "-kfx-user-margin-left-percentage",
                     "-kfx-user-margin-right-percentage", "-kfx-user-margin-top-percentage"]:
            parent_sty[name] = orig_sty[name]

        for name, val in list(parent_sty.items()):
            if name not in HERITABLE_PROPERTIES:
                parent_sty.pop(name)
            elif name not in ARBITRARY_VALUE_PROPERTIES and name != "line-height" and split_value(val)[1] == "%":
                parent_sty.pop(name)

        kfx_layout_hints = sty.get("-kfx-layout-hints", "").split()
        self.last_kfx_heading_level = kfx_heading_level = sty.pop("-kfx-heading-level", self.last_kfx_heading_level)

        contains_block_elem = contains_text = contains_image = False
        for child in elem.findall("*"):
            contains_block_elem_, contains_text_, contains_image_ = self.simplify_styles(
                child, book_part, parent_sty, default_ordered_list_value, known_width)
            contains_block_elem = contains_block_elem or contains_block_elem_
            contains_text = contains_text or contains_text_
            contains_image = contains_image or contains_image_

            if (child.tag == "li") and (default_ordered_list_value not in [None, False]):
                default_ordered_list_value += 1

        num_children = len(elem)
        if (REVERSE_INHERITANCE and (not self.book_has_illustrated_layout_conditional_page_template or self.fixed_layout) and
                num_children > 0):

            if elem.text or elem.tail:
                log.error("elem %s with children has text or tail in %s" % (elem.tag, book_part.filename))
            else:
                child_props = collections.defaultdict(dict)
                for child in elem.findall("*"):
                    child_sty = self.get_style(child)
                    for name, val in child_sty.items():
                        if name in REVERSE_HERITABLE_PROPERTIES:
                            if val not in child_props[name]:
                                child_props[name][val] = 1
                            else:
                                child_props[name][val] += 1

                new_heritable_sty = {}
                for name, vals in child_props.items():
                    total = 0
                    most_common = None
                    for val, count in vals.items():
                        total += count
                        if most_common is None or count > vals[most_common]:
                            most_common = val

                    if total < num_children and sty.get(name) is None:
                        pass
                    elif vals[most_common] >= num_children * REVERSE_INHERITANCE_FRACTION:
                        new_heritable_sty[name] = most_common

                if len(new_heritable_sty) > 0:

                    for child in elem.findall("*"):
                        child_sty = self.get_style(child)

                        for name, new_heritable_val in new_heritable_sty.items():
                            val = child_sty.get(name)
                            if val is not None:
                                if val == new_heritable_val:
                                    child_sty.pop(name)
                            elif sty[name] != new_heritable_val:
                                child_sty[name] = sty[name]

                        self.set_style(child, child_sty)

                    sty.update(new_heritable_sty, replace=True)

        inherited_properties.update(self.non_heritable_default_properties)

        if elem.tag == "div" and not (self.fixed_layout or self.illustrated_layout or self.has_conditional_content):
            if "heading" in kfx_layout_hints and not contains_block_elem:
                elem.tag = "h" + kfx_heading_level
                inherited_properties.pop("font-size")
                inherited_properties.pop("font-weight")

                if sty.get("writing-mode", "horizontal-tb") == "horizontal-tb":
                    inherited_properties.pop("margin-top")
                    inherited_properties.pop("margin-bottom")
                else:
                    inherited_properties.pop("margin-left")
                    inherited_properties.pop("margin-right")

            elif "figure" in kfx_layout_hints and contains_image and not self.epub2_desired:
                elem.tag = "figure"
                if sty.get("writing-mode", "horizontal-tb") == "horizontal-tb":
                    inherited_properties.update({"margin-top": "1em", "margin-bottom": "1em"}, replace=True)
                else:
                    inherited_properties.update({"margin-left": "1em", "margin-right": "1em"}, replace=True)

            elif contains_text and not contains_block_elem:
                elem.tag = "p"
                if sty.get("writing-mode", "horizontal-tb") == "horizontal-tb":
                    inherited_properties.update({"margin-top": "1em", "margin-bottom": "1em"}, replace=True)
                else:
                    inherited_properties.update({"margin-left": "1em", "margin-right": "1em"}, replace=True)

        if split_value(sty.get("font-size", ""))[1] == "em":
            inherited_properties["font-size"] = "1em"

        if sty.get("background-color", "transparent") == "transparent" and sty.get("background-image", "none") == "none":
            for name in ["background-clip", "background-origin", "background-position", "background-repeat", "background-size"]:
                sty.pop(name, None)

        remove_from = inherited_properties if elem.tag == "a" else sty
        remove_from.pop("-kfx-link-color", None)
        remove_from.pop("-kfx-visited-color", None)

        for name, val in list(sty.items()):
            if val == inherited_properties.get(name, ""):
                sty.pop(name)

        self.set_style(elem, sty)

        contains_block_elem = contains_block_elem or elem.tag in {
                "aside", "caption", "div", "figure", "h1", "h2", "h3", "h4", "h5", "h6", "li", "p", "td",
                IDX_ENTRY}
        contains_text = contains_text or elem.text is not None and len(elem.text) > 0
        contains_image = contains_image or elem.tag == "img" or elem.tag == "svg"

        return (contains_block_elem, contains_text, contains_image)

    def add_composite_and_equivalent_styles(self, elem, book_part):
        sty = self.get_style(elem)

        for combined_prop, individual_props in COMPOSITE_SIDE_STYLES:
            val = sty.get(individual_props[0], None)
            if val is not None:
                for individual_prop in individual_props[1:]:
                    if sty.get(individual_prop, None) != val:
                        break
                else:
                    sty[combined_prop] = val
                    for individual_prop in individual_props:
                        sty.pop(individual_prop)

        for name, val in list(sty.items()):
            alt_name = ALTERNATE_EQUIVALENT_PROPERTIES.get(name)
            if alt_name is not None:
                if name == "text-combine-upright" and val == "all":
                    sty[alt_name] = "horizontal"
                else:
                    sty[alt_name] = val

        display = sty.get("display", "")
        ineffective_properties = []

        if display == "inline" or (elem.tag in INLINE_ELEMENTS and display not in {"block", "inline-block"}):
            ineffective_properties.extend([
                    "list-style-image", "list-style-position", "list-style-type",
                    "column-count", "text-align", "text-align-last", "text-indent"])

            if elem.tag != "img":
                ineffective_properties.extend([
                        "height", "width", "max-height", "max-width", "overflow",
                        "-amzn-page-align", "-amzn-page-footer", "-amzn-page-header"])

        if ineffective_properties:
            ineffective_sty = sty.partition(property_names=ineffective_properties, modify=False)

            if ineffective_sty:
                log.warning("Ineffective property in %s element for kfx-style %s in %s: %s" % (
                        elem.tag, sty.get("-kfx-style-name", "?"), book_part.filename, ineffective_sty.tostring()))

        self.set_style(elem, sty)

        for child in elem.findall("*"):
            self.add_composite_and_equivalent_styles(child, book_part)

    def fix_and_quote_font_family_list(self, value):
        return ",".join(remove_duplicates(
            [self.quote_font_name(name) for name in self.split_and_fix_font_family_list(value)]))

    def split_and_fix_font_family_list(self, value):
        return [self.fix_font_name(name) for name in value.split(",")]

    def strip_font_name(self, name):
        name = name.strip()

        if name[0] == "'" or name[0] == "\"":
            name = name[1:]

        if name[-1] == "'" or name[-1] == "\"":
            name = name[:-1]

        return name.strip()

    def fix_font_name(self, name, add=False, generic=False):

        name = self.strip_font_name(name)

        orig_name = name.lower()

        fixed_name = self.fixed_font_names.get(orig_name)
        if fixed_name is not None:
            return fixed_name

        name = name.replace("\\", "")

        name = re.sub(r"-(oblique|italic|bold|regular|roman|medium)$", r" \1", name, flags=re.IGNORECASE)
        name = MISSPELLED_FONT_NAMES.get(name.lower(), name)

        has_prefix = "-" in name and name != "sans-serif"
        if has_prefix:
            name = name.replace("sans-serif", "sans_serif")
            name = name.rpartition("-")[2]
            name = name.replace("sans_serif", "sans-serif")

        name = name.strip()

        if add:
            lower_name = ("?-" if has_prefix else "") + name.lower()
            if lower_name not in self.font_name_replacements:
                self.font_name_replacements[lower_name] = name
            elif self.font_name_replacements[lower_name] != name:
                log.warning("KFX font family name %s changed from %s to %s" % (
                    orig_name, name, self.font_name_replacements[lower_name]))
                name = self.font_name_replacements[lower_name]

            if not generic:
                self.present_font_names.add(name)

        else:
            name = self.font_name_replacements.get(name.lower(), capitalize_font_name(name))

            if name not in GENERIC_FONT_NAMES:
                self.used_font_names.add(name)

        self.fixed_font_names[orig_name] = name

        return name

    def fix_language(self, lang):
        prefix, sep, suffix = lang.partition("-")

        if len(suffix) < 4:
            suffix = suffix.upper()
        else:
            suffix = suffix[0].upper() + suffix[1:]

        return prefix + sep + suffix

    def fix_color_value(self, value):
        if isstring(value) and not re.match(r"^[0-9]+$", value):
            return value

        color = int(value)
        return self.color_str(color, self.int_to_alpha(color >> 24))

    def add_color_opacity(self, value, opacity):
        if opacity is None or opacity == "1":
            return value

        color = self.color_int(value)
        orig_alpha = self.int_to_alpha(color >> 24)

        if orig_alpha not in {0.0, 1.0}:
            log.error("Unexpected combination of alpha (%s) and opacity (%s) for color %s" % (orig_alpha, opacity, value))

        return self.color_str(color, float(opacity))

    def color_str(self, rgb_int, alpha=1.0):
        if alpha == 1.0:
            hex_color = "#%06x" % (rgb_int & 0x00ffffff)
            if hex_color in COLOR_NAME:
                return COLOR_NAME[hex_color]

            return "#000" if hex_color == "#000000" else ("#fff" if hex_color == "#ffffff" else hex_color)

        red = (rgb_int & 0x00ff0000) >> 16
        green = (rgb_int & 0x0000ff00) >> 8
        blue = (rgb_int & 0x000000ff)
        alpha_str = "0" if alpha == 0.0 else "%0.3f" % alpha

        return "rgba(%d,%d,%d,%s)" % (red, green, blue, alpha_str)

    def color_int(self, color):

        if color in COLOR_HEX:
            color = COLOR_HEX[color]

        m = re.match(r"^#([0-9a-f]{3,6})$", color, flags=re.IGNORECASE)
        if m:
            rgb = m.group(1)
            if len(rgb) == 3:
                rgb = rgb[0] + rgb[0] + rgb[1] + rgb[1] + rgb[2] + rgb[2]

            return 0xff000000 + int(rgb, 16)

        m = re.match(r"^rgba\(([0-9]+),([0-9]+),([0-9]+),([0-9.]+)\)$", color, flags=re.IGNORECASE)
        if m:
            red = int(m.group(1))
            green = int(m.group(2))
            blue = int(m.group(3))
            alpha_int = self.alpha_to_int(float(m.group(4)))
            return (alpha_int << 24) + (red << 16) + (green << 8) + blue

        raise Exception("cannot parse color value: %s" % color)

    def int_to_alpha(self, alpha_int):
        if alpha_int < 2:
            return 0.0

        if alpha_int > 253:
            return 1.0

        return max(min(float(alpha_int + 1) / 256.0, 1.0), 0.0)

    def alpha_to_int(self, alpha):
        if alpha < 0.012:
            return 0

        if alpha > 0.996:
            return 255

        return max(min(int(alpha * 256.0 + 0.5) - 1, 255), 0)

    def pixel_value(self, value, adjust=True):
        if value is None:
            return None

        if ion_type(value) is IonStruct:
            unit = value.pop("$306")
            if unit != "$319":
                log.error("%s Expected px value, found %s" % (self.content_context, unit))

            value = value.pop("$307")

        if ion_type(value) in [IonDecimal, IonFloat]:
            value = int(value)

        if ion_type(value) is not IonInt:
            log.error("%s Expected int for px value, found %s" % (self.content_context, type_name(value)))
            return value

        if adjust:
            value = self.adjust_pixel_value(value)

        return value

    def adjust_pixel_value(self, value):
        if self.is_pdf_backed:
            px_value = round(value / 100, 2)

            value = px_value

        return value

    def add_class(self, elem, class_name, before=False):
        classes = elem.get("class", "").split()
        if class_name and class_name not in classes:
            if before:
                classes.insert(0, class_name)
            else:
                classes.append(class_name)

            elem.set("class", " ".join(classes))

    def get_style(self, elem, remove=False):
        return self.Style(elem.attrib.pop("style", "") if remove else elem.get("style", ""))

    def set_style(self, elem, new_style):
        if type(new_style) is not Style:
            raise Exception("set_style: type %s" % type_name(new_style))

        style_str = new_style.tostring()
        if style_str:
            elem.set("style", style_str)
        else:
            elem.attrib.pop("style", None)

    def add_style(self, elem, new_style, replace=None):
        if type(new_style) is not Style and type(new_style) is not dict:
            raise Exception("add_style: type %s" % type_name(new_style))

        if new_style:
            orig_style_str = elem.get("style", "")

            if orig_style_str:
                new_style = self.Style(orig_style_str).update(new_style, replace)
            elif type(new_style) is not Style:
                new_style = self.Style(new_style)

            self.set_style(elem, new_style)

    def create_css_files(self):
        for css_file in sorted(list(self.css_files)):
            if css_file == self.RESET_CSS_FILEPATH:
                self.manifest_resource(self.RESET_CSS_FILEPATH, data=RESET_CSS_DATA.encode("utf-8"), mimetype="text/css")

            elif css_file == self.STYLES_CSS_FILEPATH:
                css_lines = ["@charset \"UTF-8\";"]

                if self.font_faces:
                    css_lines.extend(["@font-face {%s}" % ff.tostring() for ff in sorted(self.font_faces)])

                if self.css_rules:
                    css_lines.extend(["%s {%s}" % (cn, self.css_rules[cn]) for cn in sorted(
                                self.css_rules.keys(), key=natural_sort_key)])

                for mq, css_rules in sorted(self.media_queries.items()):
                    css_lines.append("@media %s {" % mq)
                    css_lines.extend(["    %s {%s}" % (cn, css_rules[cn]) for cn in sorted(css_rules.keys(), key=natural_sort_key)])
                    css_lines.append("}")

                self.manifest_resource(
                    self.STYLES_CSS_FILEPATH, data="\n".join(css_lines).encode("utf-8"), mimetype="text/css")

    def quote_font_name(self, value):
        for ident in value.split(" "):
            if len(ident) == 0:
                break

            if re.match("^(-?[0-9]|--)", ident) or not re.match("^[-_a-zA-Z0-9]*$", ident):
                break
        else:
            return value

        return self.quote_css_str(value)

    def css_url(self, val):
        return "url(%s)" % (self.quote_css_str(val) if re.search("[ ()'\"\\\\]", val) else val)

    def quote_css_str(self, val):

        if not re.search("['\\\\]", val):
            return "'%s'" % val

        return "\"%s\"" % re.sub("([\"\\\\])", "\\\\\\1", val)


@functools.total_ordering
class Style(object):
    def __init__(self, src, sstr=None):
        self.style_str = self.properties = None

        if type(src) is etree.Element:
            src = src.get("style", "")

        if isinstance(src, bytes):
            src = src.decode("ascii")

        if isinstance(src, str):
            src = self.get_properties(src)

        if isinstance(src, dict):
            self.properties = dict(src)
            self.style_str = sstr
        else:
            raise Exception("Cannot create style from %s" % type_name(src))

    def get_properties(self, style_str):
        if style_str == "None":
            raise Exception("Unexpected 'None' encountered in style")

        if style_str not in style_cache:
            style_cache[style_str] = properties = {}

            for property in re.split(r"((?:[^;\(]|\([^\)]*\))+)", style_str)[1::2]:
                property = property.strip()
                if property:
                    name, sep, value = property.partition(":")
                    name = name.strip()
                    value = value.strip()

                    if sep != ":":
                        log.error("Malformed property %s in style: %s" % (name, style_str))
                    else:
                        if name in properties and properties[name] != value:
                            log.error("Conflicting property %s values in style: %s" % (name, style_str))

                        properties[name] = value

        return dict(style_cache[style_str])

    def tostring(self):
        if self.style_str is None:
            self.style_str = "; ".join(["%s: %s" % s for s in sorted(self.properties.items())])

        return self.style_str

    def keys(self):
        return self.properties.keys()

    def items(self):
        return self.properties.items()

    def get(self, key, default=None):
        return self.properties.get(key, default)

    def __len__(self):
        return len(self.properties)

    def __repr__(self):
        return self.tostring()

    def __str__(self):
        return self.tostring()

    def __eq__(self, other):
        if not isinstance(other, Style):
            raise Exception("Style __eq__: comparing with %s" % type_name(other))

        if self.style_str is not None and other.style_str is not None:
            return self.style_str == other.style_str

        return self.properties == other.properties

    def __lt__(self, other):
        if not isinstance(other, Style):
            raise Exception("Style __lt__: comparing with %s" % type_name(other))

        return self.tostring() < other.tostring()

    def __hash__(self):
        return hash(self.tostring())

    def __getitem__(self, key):
        return self.properties[key]

    def __contains__(self, key):
        return key in self.properties

    def __setitem__(self, key, value):
        self.properties[key] = value
        self.style_str = None

    def pop(self, key, default=None):
        value = self.properties.pop(key, default)
        self.style_str = None
        return value

    def clear(self):
        self.properties = {}
        self.style_str = None
        return self

    def copy(self):
        return Style(self.properties, self.style_str)

    def update(self, other, replace=None):
        if type(other) is Style:
            other = other.properties

        for name, value in other.items():
            if (name in CONFLICTING_PROPERTIES) and not CONFLICTING_PROPERTIES[name].isdisjoint(set(self.properties.keys())):
                log.error("Setting conflicting property: %s with %s" % (name, list_symbols(self.properties.keys())))

            if name in self.properties and self.properties[name] != value:
                if replace is Exception:
                    raise Exception("Setting conflicting property value: %s = %s >> %s" % (name, self.properties[name], value))

                if replace is None:
                    log.error("Setting conflicting property value: %s = %s >> %s" % (name, self.properties[name], value))
                elif not replace:
                    continue

            self.properties[name] = value
            self.style_str = None

        return self

    def partition(self, property_names=None, name_prefix=None, remove_prefix=False, add_prefix=False, keep=False, keep_all=False, modify=True):

        match_props = {}
        other_props = {}

        for name, value in self.properties.items():
            if name_prefix is not None:
                if add_prefix:
                    name = "%s-%s" % (name_prefix, name)
                    match = True
                else:
                    match = name.startswith(name_prefix)

                if match and remove_prefix:
                    name = name[len(name_prefix):]
            else:
                match = (name in property_names)

            if match:
                match_props[name] = value
            else:
                other_props[name] = value

        if keep and modify:
            self.properties = match_props
            self.style_str = None

        if keep or keep_all:
            return Style(other_props)

        if modify:
            self.properties = other_props
            self.style_str = None

        return Style(match_props)

    def remove_default_properties(self, default_style):
        defaults = default_style.properties

        for name, value in self.properties.items():
            if value == defaults.get(name, ""):
                self.properties.pop(name)
                self.style_str = None

        return self


def zero_quantity(val):

    if re.match(r"^#[0-9a-f]+$", val) or re.match(r"^rgba\([0-9]+,[0-9]+,[0-9]+,[0-9.]+\)$", val) or val in COLOR_NAMES:
        return "#0"

    num_match = re.match(r"^([+-]?[0-9]+\.?[0-9]*)(|em|ex|ch|rem|vw|vh|vmin|vmax|%|cm|mm|in|px|pt|pc)$", val)
    if num_match:
        return "0"

    return val


def split_value(val):
    num_match = re.match(r"^([+-]?[0-9]+\.?[0-9]*)", val)
    if not num_match:
        return (None, val)

    num = num_match.group(1)
    unit = val[len(num):]

    return (decimal.Decimal(num), unit)


def capitalize_font_name(name):
    return " ".join([(word.capitalize() if len(word) > 2 else word.upper()) for word in name.split(" ")])


def class_selector(class_name):
    return "." + class_name
