Polish and document 0.1.0

3 files changed, 63 insertions, 17 deletions

diff --git a/README.md b/README.md
index 77fe625..0638e19 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,23 @@ This Python package depends on [bleach] for HTML sanitising
 and [markdown] for, well, rendering Markdown to HTML.  It is, however,
 not designed to work with HTML emails with all those CSS and Java scripts.
 
+## Usage
+
+```console
+$ formbox --help
+usage: formbox [-h] mbox id template
+
+format mbox as HTML/XML
+
+positional arguments:
+  mbox        path to mbox file
+  id          root message ID
+  template    path to template
+
+optional arguments:
+  -h, --help  show this help message and exit
+```
+
 ## Copying
 
 This program is free software: you can redistribute it and/or modify
diff --git a/pyproject.toml b/pyproject.toml
index 6faa001..2cdba01 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "flit_core.buildapi"
 
 [project]
 name = "formbox"
-version = "0.0.1"
+version = "0.1.0"
 description = "Format mbox as HTML/XML"
 readme = "README.md"
 requires-python = ">=3.7"
@@ -13,10 +13,11 @@ authors = [ { name = "Nguyễn Gia Phong", email = "mcsinyx@disroot.org" } ]
 maintainers = [ { name = "Nguyễn Gia Phong", email = "mcsinyx@disroot.org" } ]
 keywords = [ "email", "format", "html", "mbox", "template", "xml" ]
 classifiers = [
-    "Development Status :: 3 - Alpha",
+    "Development Status :: 4 - Beta",
     "License :: OSI Approved :: GNU Affero General Public License v3 or later (AGPLv3+)",
     "Operating System :: OS Independent",
     "Programming Language :: Python",
     "Topic :: Utilities" ]
 dependencies = [ "bleach", "markdown" ]
-urls = { Git = "https://git.sr.ht/~cnx/formbox" }
+urls = { SourceHut = "https://sr.ht/~cnx/formbox" }
+scripts = { formbox = "formbox:main" }
diff --git a/src/formbox.py b/src/formbox.py
index 39e6132..16c0221 100644
--- a/src/formbox.py
+++ b/src/formbox.py
@@ -19,10 +19,9 @@ from argparse import ArgumentParser
 from email.header import decode_header
 from email.utils import parsedate_to_datetime
 from functools import partial
-from itertools import starmap
 from mailbox import mbox
 from pathlib import Path
-from urllib.parse import quote
+from urllib.parse import quote, unquote, urlencode
 
 from bleach import clean, linkify
 from markdown import markdown
@@ -34,6 +33,7 @@ sanitise = partial(clean, tags=('a', 'code', 'em', 'strong', 'sub', 'sup',
 
 
 def extract(archive, parent):
+    """Recursively extract emails in reply to given message ID."""
     for message_id, message in archive.copy().items():
         # TODO: handle multipart
         if message['In-Reply-To'] != parent: continue
@@ -42,30 +42,58 @@ def extract(archive, parent):
 
 
 def decode(header):
+    """Return the decoded email header."""
     for string, charset in decode_header(header):
         encoding = 'utf-8' if charset is None else charset
         yield string.decode(encoding)
 
 
+def reply_to(message):
+    """Return mailto parameters for replying to the given email."""
+    yield 'In-Reply-To', message['Message-ID']
+    yield 'Cc', message.get('Reply-To', message['From'])
+    subject = message['Subject']
+    if subject is None: return
+    if subject.lower().startswith('re:'):
+        yield 'Subject', subject
+    else:
+        yield 'Subject', f'Re: {subject}'
+
+
+def date(message):
+    """Parse given email's Date header."""
+    return parsedate_to_datetime(message['Date']).date()
+
+
 def render(template, forest, parent):
+    """Render the thread recursively based on given template."""
     for self, children in forest:
         message_id = self['Message-Id']
-        date = parsedate_to_datetime(self['Date']).date().isoformat()
-        author, address = decode(self['From'])
+        try:
+            author, address = decode(self['From'])
+        except ValueError:
+            author = self['From']
         body = sanitise(linkify(markdown(self.get_payload(),
                                          output_format='html5')))
         rendered_children = render(template, children, message_id)
         yield template.format(message_id=quote(message_id),
-                              date=date, author=author, body=body,
-                              children='\n'.join(rendered_children))
+                              mailto_params=urlencode(dict(reply_to(self))),
+                              date=date(self).isoformat(), author=author,
+                              body=body, children='\n'.join(rendered_children))
+
+
+def main():
+    """Parse command-line arguments and pass them to routines."""
+    parser = ArgumentParser(description='format mbox as HTML/XML')
+    parser.add_argument('mbox', help='path to mbox file')
+    parser.add_argument('id', type=unquote, help='root message ID')
+    parser.add_argument('template', type=Path, help='path to template')
+    args = parser.parse_args()
 
+    archive = {m['Message-Id']: m for m in sorted(mbox(args.mbox), key=date)}
+    template = args.template.read_text()
+    print(*render(template, extract(archive, args.id), args.id),
+          sep='', end='')
 
-parser = ArgumentParser()
-parser.add_argument('mbox')
-parser.add_argument('id')
-parser.add_argument('template', type=Path)
-args = parser.parse_args()
 
-archive = {m['Message-Id']: m for m in mbox(args.mbox)}
-template = args.template.read_text()
-print(*render(template, extract(archive, args.id), args.id), sep='', end='')
+if __name__ == '__main__': main()