#!/bin/sh

URL="$1"
[ -z "$URL" ] && { echo "Usage: $0 <youtube-url>"; exit 1; }

HTML=$(curl -sL "$URL")

CHANNEL_ID=$(printf "%s\n" "$HTML" | grep -oE '"channelId":"UC[^\"]+' | sed 's/.*"channelId":"//' | head -n1)

if [ -z "$CHANNEL_ID" ]; then
    CHANNEL_ID=$(printf "%s\n" "$HTML" | grep -oE 'href="/channel/UC[^"]+' | sed 's|href="/channel/||' | head -n1)
fi

if [ -n "$CHANNEL_ID" ]; then
    echo "https://www.youtube.com/feeds/videos.xml?channel_id=$CHANNEL_ID"
else
    echo "Channel ID not found"
    exit 1
fi