from sqlalchemy.orm import Session
from xml.etree import ElementTree as ET
from xml.sax.saxutils import escape
from email.utils import format_datetime
from datetime import datetime
from .database import Program, Episode

def get_base_url(request):
    # Retrieve base URL for constructing absolute paths (from FastAPI Request)
    return str(request.base_url).rstrip('/')

def generate_master_opml(db: Session, base_url: str, station: str = None):
    opml_outlines = []
    
    # Radio 357
    r357 = db.query(Program).filter_by(station="radio357").order_by(Program.name).all() if not station or station == "radio357" else []
    if r357:
        opml_outlines.append('    <outline text="Radio 357">')
        for prog in r357:
            title = escape(prog.name, {'"': "&quot;", "'": "&apos;"})
            xmlUrl = f"{base_url}/feeds/radio357/{prog.slug}.xml"
            opml_outlines.append(f'      <outline text="{title}" type="rss" xmlUrl="{xmlUrl}" />')
        opml_outlines.append('    </outline>')
        
    # RNŚ
    rns = db.query(Program).filter_by(station="rns").order_by(Program.name).all() if not station or station == "rns" else []
    if rns:
        opml_outlines.append('    <outline text="Radio Nowy Świat">')
        for prog in rns:
            title = escape(prog.name, {'"': "&quot;", "'": "&apos;"})
            xmlUrl = f"{base_url}/feeds/rns/{prog.slug}.xml"
            opml_outlines.append(f'      <outline text="{title}" type="rss" xmlUrl="{xmlUrl}" />')
        opml_outlines.append('    </outline>')
        
    # Radio Jazz FM (Direct to source feeds!)
    jazz = db.query(Program).filter_by(station="jazz").order_by(Program.name).all() if not station or station == "jazz" else []
    if jazz:
        opml_outlines.append('    <outline text="Radio Jazz FM">')
        for prog in jazz:
            title = escape(prog.name, {'"': "&quot;", "'": "&apos;"})
            # Link directly to their server!
            xmlUrl = f"https://podkasty.radiojazz.fm/@{prog.slug}/feed.xml"
            opml_outlines.append(f'      <outline text="{title}" type="rss" xmlUrl="{xmlUrl}" />')
        opml_outlines.append('    </outline>')
        
    xml_content = '<?xml version="1.0" encoding="UTF-8"?>\n'
    xml_content += '<opml version="1.0">\n  <body>\n'
    xml_content += '\n'.join(opml_outlines) + '\n'
    xml_content += '  </body>\n</opml>'
    return xml_content

def generate_podcast_rss(db: Session, station: str, slug: str):
    prog = db.query(Program).filter_by(station=station, slug=slug).first()
    if not prog:
        return None
        
    eps = db.query(Episode).filter_by(station=station, program_slug=slug, is_broken=False).filter(Episode.url.isnot(None)).order_by(Episode.pub_date.desc()).all()
    
    rss = ET.Element("rss", {"version": "2.0", "xmlns:itunes": "http://www.itunes.com/dtds/podcast-1.0.dtd"})
    channel = ET.SubElement(rss, "channel")
    
    ET.SubElement(channel, "title").text = prog.name
    ET.SubElement(channel, "description").text = prog.description or ""
    
    if prog.image:
        ET.SubElement(channel, "itunes:image", {"href": prog.image})
        image_el = ET.SubElement(channel, "image")
        ET.SubElement(image_el, "url").text = prog.image
        ET.SubElement(image_el, "title").text = prog.name
        
    for ep in eps:
        item = ET.SubElement(channel, "item")
        
        date_prefix = f"({ep.pub_date[:10]}) " if ep.pub_date else ""
        ET.SubElement(item, "title").text = f"{date_prefix}{ep.title}"
        ET.SubElement(item, "itunes:author").text = ep.authors or ""
        
        if ep.description:
            ET.SubElement(item, "description").text = ep.description
            ET.SubElement(item, "itunes:summary").text = ep.description
            
        if ep.pub_date:
            try:
                # radio357 format: 2024-03-22T08:00:00+00:00 or rns: 2024-03-22
                if 'T' in ep.pub_date:
                    dt = datetime.fromisoformat(ep.pub_date)
                else:
                    dt = datetime.strptime(ep.pub_date, "%Y-%m-%d")
                ET.SubElement(item, "pubDate").text = format_datetime(dt)
            except:
                ET.SubElement(item, "pubDate").text = ep.pub_date
                
        if ep.duration_secs:
            ET.SubElement(item, "itunes:duration").text = str(ep.duration_secs)
            
        ET.SubElement(item, "guid", {"isPermaLink": "false"}).text = f"{station}-{ep.ep_id}"
        ET.SubElement(item, "enclosure", {"url": ep.url, "type": "audio/mpeg", "length": "0"})
        
        if ep.image or prog.image:
            ET.SubElement(item, "itunes:image", {"href": ep.image or prog.image})
            
    tree = ET.ElementTree(rss)
    try:
        ET.indent(tree, space="  ", level=0)
    except AttributeError:
        pass # older python versions
        
    from io import BytesIO
    f = BytesIO()
    tree.write(f, encoding="utf-8", xml_declaration=True)
    return f.getvalue()