Ability to output GM sheets as EPUB files (without CSS for now).

dungeonsheets/epub.py

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+from typing import Mapping
+
+from ebooklib import epub
+from docutils import core
+from sphinx.util.docstrings import prepare_docstring
+from docutils.writers.html5_polyglot import Writer as HTMLWriter
+
+from dungeonsheets.latex import dice_re
+
+
+def create_epub(
+        chapters: Mapping,
+        title: str,
+        basename: str,
+        use_dnd_decorations: bool = False
+):
+    """Prepare an EPUB file from the list of chapters.
+
+    Parameters
+    ==========
+    chapters
+      A mapping where the keys are chapter names (spines) and the
+      values are strings of HTML to be rendered as the chapter
+      contents.
+    basename
+      The basename for saving files (PDFs, etc). The resulting epub
+      file will be "{basename}.epub".
+    use_dnd_decorations
+      If true, style sheets will be included to produce D&D stylized
+      stat blocks, etc.
+
+    """
+    # Create a new epub book
+    book = epub.EpubBook()
+    book.set_identifier('id123456')
+    book.set_title(title)
+    book.set_language('en')
+    # Create the separate chapters
+    html_chapters = []
+    for chap_title, content in chapters.items():
+        chap_fname = "{}.html".format(chap_title.replace(" ", "_").lower())
+        chapter = epub.EpubHtml(title=chap_title, file_name=chap_fname, lang="en")
+        chapter.set_content(content)
+        book.add_item(chapter)
+        html_chapters.append(chapter)
+    # Add the table of contents
+    book.toc = html_chapters
+    book.spine = ("nav", *html_chapters)
+    # add default NCX and Nav file
+    book.add_item(epub.EpubNcx())
+    book.add_item(epub.EpubNav())
+    # Save the file
+    epub_fname = f"{basename}.epub"
+    epub.write_epub(epub_fname, book)
+
+
+def html_parts(
+    input_string,
+    source_path=None,
+    destination_path=None,
+    input_encoding="unicode",
+    doctitle=True,
+    initial_header_level=1,
+):
+    """
+    Given an input string, returns a dictionary of HTML document parts.
+
+    Dictionary keys are the names of parts, and values are Unicode strings;
+    encoding is up to the client.
+
+    Parameters:
+
+    - `input_string`: A multi-line text string; required.
+    - `source_path`: Path to the source file or object.  Optional, but useful
+      for diagnostic output (system messages).
+    - `destination_path`: Path to the file or object which will receive the
+      output; optional.  Used for determining relative paths (stylesheets,
+      source links, etc.).
+    - `input_encoding`: The encoding of `input_string`.  If it is an encoded
+      8-bit string, provide the correct encoding.  If it is a Unicode string,
+      use "unicode", the default.
+    - `doctitle`: Disable the promotion of a lone top-level section title to
+      document title (and subsequent section title to document subtitle
+      promotion); enabled by default.
+    - `initial_header_level`: The initial level for header elements (e.g. 1
+      for "<h1>").
+    """
+    # Remove indentation, etc
+    input_string = "\n".join(prepare_docstring(input_string))
+    # Parse from rst to TeX
+    overrides = {
+        "input_encoding": input_encoding,
+        "doctitle_xform": doctitle,
+        "initial_header_level": initial_header_level,
+    }
+    writer = HTMLWriter()
+    parts = core.publish_parts(
+        source=input_string,
+        source_path=source_path,
+        destination_path=destination_path,
+        writer=writer,
+        settings_overrides=overrides,
+    )
+    return parts
+
+
+def rst_to_html(rst, top_heading_level=0):
+    """Basic markup of reST to HTML code.
+
+    The translation between reST headings and LaTeX headings is
+    modified by the *top_heading_level* parameter. A value of 0
+    (default) translates "# Heading" -> "<h1>{Heading}</h1>". A value
+    of 1 translates "# Heading" -> "<h2>{Heading}</h2>", etc.
+
+    Note: heading translation is currently broken.
+
+    Parameters
+    ==========
+    rst
+      reStructured text input to be parsed.
+    top_heading_level : optional
+      The highest level heading that will be added to the HTML as
+      described above.
+
+    Returns
+    =======
+    html : str
+      The reST text parsed into HTML markup.
+
+    """
+    if rst is None:
+        # No reST, so return an empty string
+        html = ""
+    else:
+        # Mark hit dice in monospace font
+        rst = dice_re.sub(r"``\1``", rst)
+        _html_parts = html_parts(rst)
+        html = _html_parts["body"]
+    return html