import xml.etree.ElementTree as ET
from datetime import datetime
import os
from app import generate_headline_and_description

def get_next_episode_number(podcast_dir="podcasts"):
    files = [f for f in os.listdir(podcast_dir) if f.endswith(".wav")]
    return len(files) + 1

def update_rss(subject, audio_url, audio_length, rss_path="rss.xml"):
    # Generate headline and description automatically
    title, description = generate_headline_and_description(subject)
    
    tree = ET.parse(rss_path)
    root = tree.getroot()
    channel = root.find("channel")
    
    # Update lastBuildDate
    last_build_date = channel.find("lastBuildDate")
    now_rfc2822 = datetime.utcnow().strftime("%a, %d %b %Y %H:%M:%S +0000")
    if last_build_date is not None:
        last_build_date.text = now_rfc2822
    
    # Create new item
    item = ET.Element("item")
    ET.SubElement(item, "title").text = title
    ET.SubElement(item, "description").text = description
    ET.SubElement(item, "pubDate").text = now_rfc2822
    ET.SubElement(item, "enclosure", url=audio_url, length=str(audio_length), type="audio/mpeg")
    ET.SubElement(item, "guid").text = audio_url
    ET.SubElement(item, "itunes:explicit").text = "false"
    
    # Insert new item after lastBuildDate (i.e., as the first item)
    # Find the first <item> and insert before it, or append if none exist
    items = channel.findall("item")
    if items:
        channel.insert(list(channel).index(items[0]), item)
    else:
        channel.append(item)
    
    # Write back to file
    tree.write(rss_path, encoding="utf-8", xml_declaration=True)