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use pymdownx extensions
[etc/neomutt.git] / .config / neomutt / buildmimetree.py
index 57fc21a3ced7e6f72c99d6e569caf7dcd7238536..f805884cf5048b5cc6234995b0b4d80713023677 100755 (executable)
@@ -6,8 +6,10 @@
 #
 # Configuration:
 #   neomuttrc (needs to be a single line):
+#     set my_mdwn_extensions="extra,admonition,codehilite,sane_lists,smarty"
 #     macro compose B "\
-#       <enter-command> source '$my_confdir/buildmimetree.py setup|'<enter>\
+#       <enter-command> source '$my_confdir/buildmimetree.py \
+#       --tempdir $tempdir --extensions $my_mdwn_extensions|'<enter>\
 #       <enter-command> sourc e \$my_mdwn_postprocess_cmd_file<enter>\
 #     " "Convert message into a modern MIME tree with inline images"
 #
@@ -36,7 +38,13 @@ import pathlib
 import markdown
 import tempfile
 import argparse
-from collections import namedtuple
+import re
+import mimetypes
+from collections import namedtuple, OrderedDict
+from markdown.extensions import Extension
+from markdown.inlinepatterns import ImageInlineProcessor, IMAGE_LINK_RE
+from email.utils import make_msgid
+from urllib import request
 
 
 def parse_cli_args(*args, **kwargs):
@@ -51,61 +59,48 @@ def parse_cli_args(*args, **kwargs):
         "Released under the MIT licence"
     )
 
-    subp = parser.add_subparsers(help="Sub-command parsers", dest="mode")
-    parser_setup = subp.add_parser("setup", help="Setup phase")
-    parser_massage = subp.add_parser("massage", help="Massaging phase")
-
-    parser_setup.add_argument(
-        "--debug-commands",
-        action="store_true",
-        help="Turn on debug logging of commands generated to stderr",
+    parser.add_argument(
+        "--extensions",
+        type=str,
+        default="",
+        help="Markdown extension to use (comma-separated list)"
     )
 
-    parser_setup.add_argument(
-        "--extension",
-        "-x",
-        metavar="EXTENSION",
-        dest="extensions",
-        nargs="?",
-        default=[],
-        action="append",
-        help="Markdown extension to add to the list of extensions use",
+    parser.add_argument(
+        "--only-build",
+        action="store_true",
+        help="Only build, don't send the message",
     )
 
-    parser_setup.add_argument(
-        "--send-message",
-        action="store_true",
-        help="Generate command(s) to send the message after processing",
+    parser.add_argument(
+        "--tempdir",
+        default=None,
+        help="Specify temporary directory to use for attachments",
     )
 
-    parser_massage.add_argument(
+    parser.add_argument(
         "--debug-commands",
         action="store_true",
         help="Turn on debug logging of commands generated to stderr",
     )
 
-    parser_massage.add_argument(
-        "--debug-walk",
-        action="store_true",
-        help="Turn on debugging to stderr of the MIME tree walk",
-    )
-
-    parser_massage.add_argument(
-        "--extensions",
-        metavar="EXTENSIONS",
-        type=str,
-        default="",
-        help="Markdown extension to use (comma-separated list)",
-    )
+    subp = parser.add_subparsers(help="Sub-command parsers", dest="mode")
+    massage_p = subp.add_parser("massage", help="Massaging phase (internal use)")
 
-    parser_massage.add_argument(
+    massage_p.add_argument(
         "--write-commands-to",
         metavar="PATH",
         dest="cmdpath",
         help="Temporary file path to write commands to",
     )
 
-    parser_massage.add_argument(
+    massage_p.add_argument(
+        "--debug-walk",
+        action="store_true",
+        help="Turn on debugging to stderr of the MIME tree walk",
+    )
+
+    massage_p.add_argument(
         "MAILDRAFT",
         nargs="?",
         help="If provided, the script is invoked as editor on the mail draft",
@@ -114,6 +109,74 @@ def parse_cli_args(*args, **kwargs):
     return parser.parse_args(*args, **kwargs)
 
 
+# [ MARKDOWN WRAPPING ] #######################################################
+
+
+InlineImageInfo = namedtuple(
+    "InlineImageInfo", ["cid", "desc"], defaults=[None]
+)
+
+
+class InlineImageExtension(Extension):
+    class RelatedImageInlineProcessor(ImageInlineProcessor):
+        def __init__(self, re, md, ext):
+            super().__init__(re, md)
+            self._ext = ext
+
+        def handleMatch(self, m, data):
+            el, start, end = super().handleMatch(m, data)
+            if "src" in el.attrib:
+                src = el.attrib["src"]
+                if "://" not in src or src.startswith("file://"):
+                    # We only inline local content
+                    cid = self._ext.get_cid_for_image(el.attrib)
+                    el.attrib["src"] = f"cid:{cid}"
+            return el, start, end
+
+    def __init__(self):
+        super().__init__()
+        self._images = OrderedDict()
+
+    def extendMarkdown(self, md):
+        md.registerExtension(self)
+        inline_image_proc = self.RelatedImageInlineProcessor(
+            IMAGE_LINK_RE, md, self
+        )
+        md.inlinePatterns.register(inline_image_proc, "image_link", 150)
+
+    def get_cid_for_image(self, attrib):
+        msgid = make_msgid()[1:-1]
+        path = attrib["src"]
+        if path.startswith("/"):
+            path = f"file://{path}"
+        self._images[path] = InlineImageInfo(
+            msgid, attrib.get("title", attrib.get("alt"))
+        )
+        return msgid
+
+    def get_images(self):
+        return self._images
+
+
+def markdown_with_inline_image_support(text, *, extensions=None):
+    inline_image_handler = InlineImageExtension()
+    extensions = extensions or []
+    extensions.append(inline_image_handler)
+    mdwn = markdown.Markdown(extensions=extensions)
+    htmltext = mdwn.convert(text)
+
+    images = inline_image_handler.get_images()
+
+    def replace_image_with_cid(matchobj):
+        for m in (matchobj.group(1), f"file://{matchobj.group(1)}"):
+            if m in images:
+                return f"(cid:{images[m].cid}"
+        return matchobj.group(0)
+
+    text = re.sub(r"\(([^)\s]+)", replace_image_with_cid, text)
+    return text, htmltext, images
+
+
 # [ PARTS GENERATION ] ########################################################
 
 
@@ -140,48 +203,68 @@ class Multipart(
         return f"<multipart/{self.subtype}> children={len(self.children)}"
 
 
-def convert_markdown_to_html(maildraft, *, extensions=None):
-    draftpath = pathlib.Path(maildraft)
-    with open(draftpath, "r", encoding="utf-8") as textmarkdown:
-        text = textmarkdown.read()
+def filewriter_fn(path, content, mode="w", **kwargs):
+    with open(path, mode, **kwargs) as out_f:
+        out_f.write(content)
 
-    mdwn = markdown.Markdown(extensions=extensions)
 
+def collect_inline_images(
+    images, *, tempdir=None, filewriter_fn=filewriter_fn
+):
+    relparts = []
+    for path, info in images.items():
+        data = request.urlopen(path)
+
+        mimetype = data.headers["Content-Type"]
+        ext = mimetypes.guess_extension(mimetype)
+        tempfilename = tempfile.mkstemp(prefix="img", suffix=ext, dir=tempdir)
+        path = pathlib.Path(tempfilename[1])
+
+        filewriter_fn(path, data.read(), "w+b")
+
+        relparts.append(
+            Part(*mimetype.split("/"), path, cid=info.cid, desc=f"Image: {info.desc}")
+        )
+
+    return relparts
+
+
+def convert_markdown_to_html(
+    origtext,
+    draftpath,
+    *,
+    filewriter_fn=filewriter_fn,
+    tempdir=None,
+    extensions=None,
+):
+    origtext, htmltext, images = markdown_with_inline_image_support(
+        origtext, extensions=extensions
+    )
 
-    with open(draftpath, "w", encoding="utf-8") as textplain:
-        textplain.write(text)
+    filewriter_fn(draftpath, origtext, encoding="utf-8")
     textpart = Part(
         "text", "plain", draftpath, "Plain-text version", orig=True
     )
 
-    html = mdwn.convert(text)
     htmlpath = draftpath.with_suffix(".html")
-    with open(
-        htmlpath, "w", encoding="utf-8", errors="xmlcharrefreplace"
-    ) as texthtml:
-        texthtml.write(html)
+    filewriter_fn(
+        htmlpath, htmltext, encoding="utf-8", errors="xmlcharrefreplace"
+    )
     htmlpart = Part("text", "html", htmlpath, "HTML version")
 
-    logopart = Part(
-        "image",
-        "png",
-        "/usr/share/doc/neomutt/logo/neomutt-256.png",
-        "Logo",
-        "neomutt-256.png",
+    altpart = Multipart(
+        "alternative", [textpart, htmlpart], "Group of alternative content"
     )
 
-    return Multipart(
-        "relative",
-        [
-            Multipart(
-                "alternative",
-                [textpart, htmlpart],
-                "Group of alternative content",
-            ),
-            logopart,
-        ],
-        "Group of related content",
+    imgparts = collect_inline_images(
+        images, tempdir=tempdir, filewriter_fn=filewriter_fn
     )
+    if imgparts:
+        return Multipart(
+            "relative", [altpart] + imgparts, "Group of related content"
+        )
+    else:
+        return altpart
 
 
 class MIMETreeDFWalker:
@@ -290,17 +373,18 @@ class MuttCommands:
 
 
 def do_setup(
-    extensions=None, *, out_f=sys.stdout, temppath=None, debug_commands=False
+    *,
+    out_f=sys.stdout,
+    temppath=None,
+    tempdir=None,
+    debug_commands=False,
 ):
-    extensions = extensions or []
     temppath = temppath or pathlib.Path(
-        tempfile.mkstemp(prefix="muttmdwn-")[1]
+        tempfile.mkstemp(prefix="muttmdwn-", dir=tempdir)[1]
     )
     cmds = MuttCommands(out_f, debug=debug_commands)
 
-    editor = f"{sys.argv[0]} massage --write-commands-to {temppath}"
-    if extensions:
-        editor = f'{editor} --extensions {",".join(extensions)}'
+    editor = f"{' '.join(sys.argv)} massage --write-commands-to {temppath}"
 
     cmds.cmd('set my_editor="$editor"')
     cmds.cmd('set my_edit_headers="$edit_headers"')
@@ -312,11 +396,14 @@ def do_setup(
 
 
 def do_massage(
-    maildraft,
+    draft_f,
+    draftpath,
     cmd_f,
     *,
     extensions=None,
     converter=convert_markdown_to_html,
+    only_build=False,
+    tempdir=None,
     debug_commands=False,
     debug_walk=False,
 ):
@@ -339,7 +426,7 @@ def do_massage(
     cmds.flush()
 
     extensions = extensions.split(",") if extensions else []
-    tree = converter(maildraft, extensions=extensions)
+    tree = converter(draft_f.read(), draftpath, tempdir=tempdir, extensions=extensions)
 
     mimetree = MIMETreeDFWalker(debug=debug_walk)
 
@@ -349,6 +436,8 @@ def do_massage(
         depth-first, and responsible for telling NeoMutt how to assemble
         the tree.
         """
+        KILL_LINE=r'\Ca\Ck'
+
         if isinstance(item, Part):
             # We've hit a leaf-node, i.e. an alternative or a related part
             # with actual content.
@@ -369,7 +458,7 @@ def do_massage(
             # information, then we might just as well update the NeoMutt
             # tree now:
             if item.cid:
-                cmds.push(f"<edit-content-id>\\Ca\\Ck{item.cid}<enter>")
+                cmds.push(f"<edit-content-id>{KILL_LINE}{item.cid}<enter>")
 
         elif isinstance(item, Multipart):
             # This node has children, but we already visited them (see
@@ -378,7 +467,7 @@ def do_massage(
             # appropriate grouping:
             if item.subtype == "alternative":
                 cmds.push("<group-alternatives>")
-            elif item.subtype == "relative":
+            elif item.subtype in ("relative", "related"):
                 cmds.push("<group-related>")
             elif item.subtype == "multilingual":
                 cmds.push("<group-multilingual>")
@@ -389,7 +478,7 @@ def do_massage(
 
         # If the item has a description, we might just as well add it
         if item.desc:
-            cmds.push(f"<edit-description>\\Ca\\Ck{item.desc}<enter>")
+            cmds.push(f"<edit-description>{KILL_LINE}{item.desc}<enter>")
 
         # Finally, if we're at non-root level, tag the new container,
         # as it might itself be part of a container, to be processed
@@ -404,6 +493,9 @@ def do_massage(
     # function
     mimetree.walk(tree, visitor_fn=visitor_fn)
 
+    if not only_build:
+        cmds.push("<send-message>")
+
     # Finally, cleanup. Since we're responsible for removing the temporary
     # file, how's this for a little hack?
     try:
@@ -420,18 +512,23 @@ def do_massage(
 if __name__ == "__main__":
     args = parse_cli_args()
 
-    if args.mode == "setup":
-        if args.send_message:
-            raise NotImplementedError()
-
-        do_setup(args.extensions, debug_commands=args.debug_commands)
+    if args.mode is None:
+        do_setup(
+            tempdir=args.tempdir,
+            debug_commands=args.debug_commands,
+        )
 
     elif args.mode == "massage":
-        with open(args.cmdpath, "w") as cmd_f:
+        with open(args.MAILDRAFT, "r") as draft_f, open(
+            args.cmdpath, "w"
+        ) as cmd_f:
             do_massage(
-                args.MAILDRAFT,
+                draft_f,
+                pathlib.Path(args.MAILDRAFT),
                 cmd_f,
                 extensions=args.extensions,
+                only_build=args.only_build,
+                tempdir=args.tempdir,
                 debug_commands=args.debug_commands,
                 debug_walk=args.debug_walk,
             )
@@ -441,6 +538,7 @@ if __name__ == "__main__":
 
 try:
     import pytest
+    from io import StringIO
 
     class Tests:
         @pytest.fixture
@@ -566,70 +664,230 @@ try:
             mimetree.walk(basic_mime_tree)
             assert len(items) == 5
 
-        def test_do_setup_no_extensions(self, const1, capsys):
-            "Assert basics about the setup command output"
-            do_setup(temppath=const1, out_f=sys.stdout)
-            captout = capsys.readouterr()
-            lines = captout.out.splitlines()
-            assert lines[2].endswith(f'{const1}"')
-            assert lines[4].endswith(const1)
-            assert "first-entry" in lines[-1]
-            assert "edit-file" in lines[-1]
-
-        def test_do_setup_extensions(self, const1, const2, capsys):
-            "Assert that extensions are passed to editor"
-            do_setup(
-                temppath=const1, extensions=[const2, const1], out_f=sys.stdout
+        @pytest.fixture
+        def string_io(self, const1, text=None):
+            return StringIO(text or const1)
+
+        def test_do_massage_basic(self, const1, string_io, capsys):
+            def converter(drafttext, draftpath, extensions, tempdir):
+                return Part("text", "plain", draftpath, orig=True)
+
+            do_massage(
+                draft_f=string_io,
+                draftpath=const1,
+                cmd_f=sys.stdout,
+                converter=converter,
             )
-            captout = capsys.readouterr()
-            lines = captout.out.splitlines()
-            # assert comma-separated list of extensions passed
-            assert lines[2].endswith(f'{const2},{const1}"')
-            assert lines[4].endswith(const1)
 
-        def test_do_massage_basic(self, const1, capsys):
-            def converter(maildraft, extensions):
-                return Part("text", "plain", "/dev/null", orig=True)
+            captured = capsys.readouterr()
+            lines = captured.out.splitlines()
+            assert '="$my_editor"' in lines.pop(0)
+            assert '="$my_edit_headers"' in lines.pop(0)
+            assert "unset my_editor" == lines.pop(0)
+            assert "unset my_edit_headers" == lines.pop(0)
+            assert "send-message" in lines.pop(0)
+            assert "update-encoding" in lines.pop(0)
+            assert "source 'rm -f " in lines.pop(0)
+            assert "unset my_mdwn_postprocess_cmd_file" == lines.pop(0)
+
+        def test_do_massage_fulltree(
+            self, string_io, const1, basic_mime_tree, capsys
+        ):
+            def converter(drafttext, draftpath, extensions, tempdir):
+                return basic_mime_tree
+
+            do_massage(
+                draft_f=string_io,
+                draftpath=const1,
+                cmd_f=sys.stdout,
+                converter=converter,
+            )
 
-            do_massage(maildraft=const1, cmd_f=sys.stdout, converter=converter)
             captured = capsys.readouterr()
+            lines = captured.out.splitlines()[4:]
+            assert "send-message" in lines.pop(0)
+            assert "Related" in lines.pop(0)
+            assert "group-related" in lines.pop(0)
+            assert "tag-entry" in lines.pop(0)
+            assert "Logo" in lines.pop(0)
+            assert "content-id" in lines.pop(0)
+            assert "toggle-unlink" in lines.pop(0)
+            assert "logo.png" in lines.pop(0)
+            assert "tag-entry" in lines.pop(0)
+            assert "Alternative" in lines.pop(0)
+            assert "group-alternatives" in lines.pop(0)
+            assert "tag-entry" in lines.pop(0)
+            assert "HTML" in lines.pop(0)
+            assert "toggle-unlink" in lines.pop(0)
+            assert "part.html" in lines.pop(0)
+            assert "tag-entry" in lines.pop(0)
+            assert "Plain" in lines.pop(0)
+            assert "update-encoding" in lines.pop(0)
+            assert len(lines) == 2
+
+        @pytest.fixture
+        def fake_filewriter(self):
+            class FileWriter:
+                def __init__(self):
+                    self._writes = []
+
+                def __call__(self, path, content, mode="w", **kwargs):
+                    self._writes.append((path, content))
+
+                def pop(self, index=-1):
+                    return self._writes.pop(index)
+
+            return FileWriter()
+
+        @pytest.fixture
+        def markdown_non_converter(self, const1, const2):
+            return lambda s, text: f"{const1}{text}{const2}"
+
+        def test_converter_tree_basic(
+            self, const1, const2, fake_filewriter, markdown_non_converter
+        ):
+            path = pathlib.Path(const2)
+            tree = convert_markdown_to_html(
+                const1, path, filewriter_fn=fake_filewriter
+            )
+
+            assert tree.subtype == "alternative"
+            assert len(tree.children) == 2
+            assert tree.children[0].subtype == "plain"
+            assert tree.children[0].path == path
+            assert tree.children[0].orig
+            assert tree.children[1].subtype == "html"
+            assert tree.children[1].path == path.with_suffix(".html")
+
+        def test_converter_writes(
+            self,
+            const1,
+            const2,
+            fake_filewriter,
+            monkeypatch,
+            markdown_non_converter,
+        ):
+            path = pathlib.Path(const2)
+
+            with monkeypatch.context() as m:
+                m.setattr(markdown.Markdown, "convert", markdown_non_converter)
+                convert_markdown_to_html(
+                    const1, path, filewriter_fn=fake_filewriter
+                )
+
+            assert (path, const1) == fake_filewriter.pop(0)
             assert (
-                captured.out.strip()
-                == """\
-            set editor="$my_editor"
-            set edit_headers="$my_edit_headers"
-            unset my_editor
-            unset my_edit_headers
-            source 'rm -f pytest_internal_file|'
-            unset my_mdwn_postprocess_cmd_file
-            """.replace(
-                    "            ", ""
-                ).strip()
+                path.with_suffix(".html"),
+                markdown_non_converter(None, const1),
+            ) == fake_filewriter.pop(0)
+
+        def test_markdown_inline_image_processor(self):
+            imgpath1 = "file:/path/to/image.png"
+            imgpath2 = "file:///path/to/image.png?url=params"
+            imgpath3 = "/path/to/image.png"
+            text = f"""![inline local image]({imgpath1})
+                       ![image inlined
+                         with newline]({imgpath2})
+                       ![image local path]({imgpath3})"""
+            text, html, images = markdown_with_inline_image_support(text)
+
+            # local paths have been normalised to URLs:
+            imgpath3 = f"file://{imgpath3}"
+
+            assert 'src="cid:' in html
+            assert "](cid:" in text
+            assert len(images) == 3
+            assert imgpath1 in images
+            assert imgpath2 in images
+            assert imgpath3 in images
+            assert images[imgpath1].cid != images[imgpath2].cid
+            assert images[imgpath1].cid != images[imgpath3].cid
+            assert images[imgpath2].cid != images[imgpath3].cid
+
+        def test_markdown_inline_image_processor_title_to_desc(self, const1):
+            imgpath = "file:///path/to/image.png"
+            text = f'![inline local image]({imgpath} "{const1}")'
+            text, html, images = markdown_with_inline_image_support(text)
+            assert images[imgpath].desc == const1
+
+        def test_markdown_inline_image_processor_alt_to_desc(self, const1):
+            imgpath = "file:///path/to/image.png"
+            text = f"![{const1}]({imgpath})"
+            text, html, images = markdown_with_inline_image_support(text)
+            assert images[imgpath].desc == const1
+
+        def test_markdown_inline_image_processor_title_over_alt_desc(
+            self, const1, const2
+        ):
+            imgpath = "file:///path/to/image.png"
+            text = f'![{const1}]({imgpath} "{const2}")'
+            text, html, images = markdown_with_inline_image_support(text)
+            assert images[imgpath].desc == const2
+
+        def test_markdown_inline_image_not_external(self):
+            imgpath = "https://path/to/image.png"
+            text = f"![inline image]({imgpath})"
+            text, html, images = markdown_with_inline_image_support(text)
+
+            assert 'src="cid:' not in html
+            assert "](cid:" not in text
+            assert len(images) == 0
+
+        def test_markdown_inline_image_local_file(self):
+            imgpath = "/path/to/image.png"
+            text = f"![inline image]({imgpath})"
+            text, html, images = markdown_with_inline_image_support(text)
+
+            for k, v in images.items():
+                assert k == f"file://{imgpath}"
+                break
+
+        @pytest.fixture
+        def test_png(self):
+            return (
+                "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAE"
+                "AAAABCAAAAAA6fptVAAAACklEQVQI12P4DwABAQEAG7buVgAA"
             )
 
-        def test_do_massage_fulltree(self, const1, basic_mime_tree, capsys):
-            def converter(maildraft, extensions):
-                return basic_mime_tree
+        def test_markdown_inline_image_processor_base64(self, test_png):
+            text = f"![1px white inlined]({test_png})"
+            text, html, images = markdown_with_inline_image_support(text)
 
-            do_massage(maildraft=const1, cmd_f=sys.stdout, converter=converter)
-            captured = capsys.readouterr()
-            lines = captured.out.splitlines()[4:][::-1]
-            assert "Related" in lines.pop()
-            assert "group-related" in lines.pop()
-            assert "tag-entry" in lines.pop()
-            assert "Logo" in lines.pop()
-            assert "content-id" in lines.pop()
-            assert "toggle-unlink" in lines.pop()
-            assert "logo.png" in lines.pop()
-            assert "tag-entry" in lines.pop()
-            assert "Alternative" in lines.pop()
-            assert "group-alternatives" in lines.pop()
-            assert "tag-entry" in lines.pop()
-            assert "HTML" in lines.pop()
-            assert "toggle-unlink" in lines.pop()
-            assert "part.html" in lines.pop()
-            assert "tag-entry" in lines.pop()
-            assert "Plain" in lines.pop()
+            assert 'src="cid:' in html
+            assert "](cid:" in text
+            assert len(images) == 1
+            assert test_png in images
+
+        def test_converter_tree_inline_image_base64(
+            self, test_png, const1, fake_filewriter
+        ):
+            text = f"![inline base64 image]({test_png})"
+            path = pathlib.Path(const1)
+            tree = convert_markdown_to_html(
+                text, path, filewriter_fn=fake_filewriter
+            )
+
+            assert tree.subtype == "relative"
+            assert tree.children[1].subtype == "png"
+            written = fake_filewriter.pop()
+            assert tree.children[1].path == written[0]
+            assert written[1] == request.urlopen(test_png).read()
+
+        def test_inline_image_collection(
+            self, test_png, const1, const2, fake_filewriter
+        ):
+            test_images = {test_png: InlineImageInfo(cid=const1, desc=const2)}
+            relparts = collect_inline_images(
+                test_images, filewriter_fn=fake_filewriter
+            )
+
+            written = fake_filewriter.pop()
+            assert b"PNG" in written[1]
+
+            assert relparts[0].subtype == "png"
+            assert relparts[0].path == written[0]
+            assert relparts[0].cid == const1
+            assert relparts[0].desc.endswith(const2)
 
 except ImportError:
     pass