# Chris Xiong 2024
# License: Expat (MIT)

import os
import re
from datetime import datetime, timezone

from monolith import Monolith
from config import conf

tagrex = re.compile(r'<[^>]+>')

def remove_tags(s):
    return tagrex.sub('', s)

def ellide(s, l):
    return s if len(s) <= l else s[:l] + " ..."

def gen_atom():
    xmlbuf  = f'<?xml version="1.0" encoding="utf-8"?>'
    xmlbuf += f'<feed xmlns="http://www.w3.org/2005/Atom">'
    xmlbuf += f'<generator uri="https://cgit.chrisoft.org/notekins.git" version="{conf.VERSION_STRING}">Notekins</generator>'
    xmlbuf += f'<updated>{datetime.now(timezone.utc).replace(microsecond=0).isoformat()}</updated>'
    xmlbuf += f'<link href="{conf.ATOM_ROOT}/atom.xml" rel="self" type="application/atom+xml" title="Atom"/>'
    xmlbuf += f'<link href="{conf.ATOM_ROOT}/" rel="alternate" type="text/html"/>'
    xmlbuf += f'<id>{conf.ATOM_ROOT}/atom.xml</id>'
    xmlbuf += f'<title>{conf.ATOM_TITLE}</title>'
    xmlbuf += f'<subtitle>{conf.ATOM_SUBTITLE}</subtitle>'
    xmlbuf += f'<icon>{conf.ATOM_ICON}</icon>'
    xmlbuf += f'<logo>{conf.ATOM_ICON}</logo>'
    m = Monolith(os.path.join(conf.LOCAL_DATA_ROOT, "posts.monolith"))
    m.load_index()
    dates = list(reversed(m.get_all_dates()[-conf.ATOM_NPOSTS:]))
    for d in dates:
        p = m.get_post(d)
        link = f"{conf.ATOM_ROOT}/?post={p.date}"
        title = ellide(remove_tags(p.content), 32)
        date = datetime.fromtimestamp(p.date, timezone.utc).replace(microsecond=0).isoformat()
        xmlbuf += f'<entry>'
        xmlbuf += f'<title>{title}</title>'
        xmlbuf += f'<link href="{link}" title="{title}"/>'
        xmlbuf += f'<published>{date}</published>'
        xmlbuf += f'<updated>{date}</updated>'
        xmlbuf += f'<id>{link}</id>'
        xmlbuf += f'<author><name>{conf.ATOM_AUTHOR}</name></author>'
        xmlbuf += f'<content type="html" xml:base="{link}"><![CDATA[{p.content}]]></content>'
        xmlbuf += f'</entry>'
    xmlbuf += f'</feed>'
    atomfn = os.path.join(conf.LOCAL_DATA_ROOT, "atom.xml")
    with open(atomfn, "w") as f:
        f.write(xmlbuf)