"""
RSS feeds for recent events and by family.
"""

import falcon
import html
from datetime import datetime
from oedb.utils.logging import logger
from oedb.utils.db import db_connect


def _rss_header(title: str, link: str, desc: str) -> str:
    return f"""<?xml version="1.0" encoding="UTF-8"?>
<rss version="2.0">
<channel>
  <title>{html.escape(title)}</title>
  <link>{html.escape(link)}</link>
  <description>{html.escape(desc)}</description>
"""


def _rss_footer() -> str:
    return """
</channel>
</rss>
"""


def _row_to_item(row) -> str:
    events_id, events_tags, createdate = row
    title = html.escape(str(events_tags.get('label') or events_tags.get('what') or f"event {events_id}"))
    link = f"https://api.openeventdatabase.org/event/{events_id}"
    guid = link
    pubdate = datetime.fromisoformat(str(createdate)).strftime('%a, %d %b %Y %H:%M:%S %z') if createdate else ''
    description = html.escape(str(events_tags))
    return f"""
  <item>
    <title>{title}</title>
    <link>{link}</link>
    <guid>{guid}</guid>
    <pubDate>{pubdate}</pubDate>
    <description>{description}</description>
  </item>
"""


class RSSLatestResource:
    def on_get(self, req, resp):
        logger.info("Processing GET /rss")
        resp.content_type = 'application/rss+xml; charset=utf-8'
        db = db_connect()
        cur = db.cursor()
        cur.execute("""
            SELECT events_id, events_tags, createdate
            FROM events
            ORDER BY createdate DESC
            LIMIT 200
        """)
        items = ''.join(_row_to_item(r) for r in cur.fetchall())
        xml = _rss_header('OEDB - Latest events', 'https://api.openeventdatabase.org/event', 'Latest 200 events') + items + _rss_footer()
        resp.text = xml


class RSSByFamilyResource:
    def on_get(self, req, resp, family: str):
        logger.info(f"Processing GET /rss/by/{family}")
        resp.content_type = 'application/rss+xml; charset=utf-8'
        db = db_connect()
        cur = db.cursor()
        like = family + '%'
        cur.execute("""
            SELECT events_id, events_tags, createdate
            FROM events
            WHERE events_what LIKE %s
            ORDER BY createdate DESC
            LIMIT 200
        """, (like,))
        items = ''.join(_row_to_item(r) for r in cur.fetchall())
        xml = _rss_header(f'OEDB - {family}', f'https://api.openeventdatabase.org/event?what={family}', f'Latest 200 events in {family}') + items + _rss_footer()
        resp.text = xml


rss_latest = RSSLatestResource()
rss_by_family = RSSByFamilyResource()