ProjectWeb/Html5ToCss3Converter.py

# -*- coding: utf-8 -*-

# Copyright (c) 2014 - 2023 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing the HTML5 to CSS3 converter.
"""

import datetime
import getpass
import os
import random

from PyQt6.QtCore import QObject
from PyQt6.QtWidgets import QDialog

from .Html5ToCss3ConverterParameterDialog import Html5ToCss3ConverterParameterDialog


class Html5ToCss3Converter(QObject):
    """
    Class implementing the HTML5 to CSS3 converter.
    """

    CssTemplate7 = "{0}{1}{2}{3}{4}{5}{6}"
    CssTemplate8 = "{0}{1}{2}{3}{4}{5}{6}{7}"
    Placeholders = (
        "margin:0",
        "padding:0",
        "border:0",
        "font-size:100%",
        "font:inherit",
        "vertical-align:baseline",
        "line-height:1",
        "outline:0",
        "font-weight:inherit",
        "font-style:inherit",
        "font-family:inherit",
        "vertical-align:baseline",
    )
    TagsToIgnore = (
        "head",
        "meta",
        "noscript",
        "script",
        "style",
        "link",
        "no-js",
        "title",
        "object",
        "col",
        "colgroup",
        "option",
        "param",
        "audio",
        "basefont",
        "isindex",
        "svg",
        "area",
        "embed",
        "br",
    )

    def __init__(self, html, parent=None):
        """
        Constructor

        @param html HTML text to be converted
        @type str
        @param parent reference to the parent object
        @type QObject
        """
        super().__init__(parent)

        self.__html = html

    def getCss3(self):
        """
        Public method to get the converted CSS3 text.

        @return CSS3 text
        @rtype str
        """
        dlg = Html5ToCss3ConverterParameterDialog()
        if dlg.exec() == QDialog.DialogCode.Accepted:
            indentation, placeholders = dlg.getData()

            self.__createSoup()

            alreadyDone = list(self.TagsToIgnore)

            css = '@charset "utf-8";{0}'.format(os.linesep)
            css += "/* {0} by {1}*/{2}".format(
                datetime.datetime.now().isoformat().split(".")[0],
                getpass.getuser(),
                2 * os.linesep,
            )

            # step 1: tags
            for tag in self.__getTags():
                if tag not in alreadyDone:
                    css += self.CssTemplate7.format(
                        tag,
                        "{",
                        os.linesep,
                        indentation,
                        random.choice(self.Placeholders) + os.linesep  # secok
                        if placeholders
                        else os.linesep,
                        "}",
                        os.linesep,
                    )
                    alreadyDone.append(tag)
            css += "/*{0}*/{1}".format("-" * 75, os.linesep)

            # step 2: IDs
            for id_ in self.__getIds():
                if id_ not in alreadyDone:
                    css += "/* {0} */{1}".format("_".join(id_).lower(), os.linesep)
                    css += self.CssTemplate8.format(
                        "#",
                        id_[1],
                        "{",
                        os.linesep,
                        indentation,
                        random.choice(self.Placeholders) + os.linesep  # secok
                        if placeholders
                        else os.linesep,
                        "}",
                        os.linesep,
                    )
                    alreadyDone.append(id_)
            css += "/*{0}*/{1}".format("-" * 75, os.linesep)

            # step 3: classes
            for class_ in self.__getClasses():
                if class_ not in alreadyDone:
                    css += "/* {0} */{1}".format("_".join(class_).lower(), os.linesep)
                    css += self.CssTemplate8.format(
                        ".",
                        ", .".join(class_[1].split()),
                        "{",
                        os.linesep,
                        indentation,
                        random.choice(self.Placeholders) + os.linesep  # secok
                        if placeholders
                        else os.linesep,
                        "}",
                        os.linesep,
                    )
                    alreadyDone.append(class_)
        else:
            css = ""
        return css.strip()

    def __createSoup(self):
        """
        Private method to get a BeaitifulSoup object with our HTML text.
        """
        from bs4 import BeautifulSoup

        self.__soup = BeautifulSoup(BeautifulSoup(self.__html).prettify())

    def __getTags(self):
        """
        Private method to extract all tags of the HTML text.

        @return list of all tags
        @rtype list of str
        """
        tags = [t.name for t in self.__soup.find_all(True)]
        return list(set(tags))

    def __getClasses(self):
        """
        Private method to extract all classes of the HTML text.

        @return list of tuples containing the tag name and its classes
            as a blank separated string
        @rtype list of tuples of (str, str)
        """
        classes = [
            (t.name, " ".join(t["class"]))
            for t in self.__soup.find_all(True, {"class": True})
        ]
        return sorted(set(classes))

    def __getIds(self):
        """
        Private method to extract all IDs of the HTML text.

        @return list of tuples containing the tag name and its ID
        @rtype list of tuples of (str, str)
        """
        ids = [(t.name, t["id"]) for t in self.__soup.find_all(True, {"id": True})]
        return sorted(set(ids))