import re
import json
import traceback

REGEXES = {
    # group 1 = single image id, or "gallery", or "a"
    # group 2 = empty if single image, or album/gallery id
    "imgur"  : re.compile(r"https?://(?:www.)?imgur.com/((?:(?!\/).)+)/?((?:(?![\./]).)+)?"),

    # group 1 = gfycat/redgifs id
    "gfycat" : re.compile(r"https?://(?:www.|giant.)?gfycat.com/(?:gifs/detail/)?((?:(?![\./-]).)+)"),
    "redgifs": re.compile(r"https?://(?:www.)?redgifs.com/watch/((?:(?![\./-]).)+)"),

    # group 1 = giphy id
    "giphy"  : re.compile(r'https?://(?:www.)?giphy.com/gifs/(?:.*\-)?((?:(?![\./-]).)+)'),

    # group 1 = tenor id
    "tenor"  : re.compile(r'https?://(?:www.)?tenor.com?/view/(?:.*\-)?((?:(?![\./-]).)+)')
}

GIPHY_DIRECT_URL = "https://media.giphy.com/media/{0}/giphy.gif"

def _match_url(url):
    for site, regex in REGEXES.items():
        match = regex.match(url)
        if match:
            return (site, match)
    return (None, None)

async def parse_image_url(session, url):
    site, match = _match_url(url)
    if not match:
        return url
    
    image_id = match.group(1)
    if site == "imgur":
        request_url = f"https://imgur.com/{image_id}"
        if image_id == "gallery" or image_id == "a":
            album_type = image_id
            album_id = match.group(2)
            request_url = f"https://imgur.com/{album_type}/{album_id}"
        
        try:
            r = await session.get(request_url)
            r.raise_for_status()
            image_page_html = await r.text()
            image_url_match = re.search(r"<meta name=\"twitter:image\" (?:.*?)content=\"(.*?)\"(?:.*?)>", image_page_html)
            image_url = image_url_match.group(1).strip() if image_url_match else None
            if not image_url:
                return url
            return image_url
        except Exception:
            traceback.print_exc()
            return url
    elif site == "gfycat" or site == "redgifs":
        try:
            r = await session.get(f"https://api.{site}.com/v1/gfycats/{image_id}")
            r.raise_for_status()
            gif_info = await r.json()
            poster_url = gif_info.get('gfyItem', {}).get('posterUrl')
            if not poster_url:
                return url
            return poster_url
        except Exception:
            traceback.print_exc()
            return url
    elif site == "giphy":
        return GIPHY_DIRECT_URL.format(image_id)
    elif site == "tenor":
        try:
            r = await session.get(f"https://tenor.com/view/{image_id}")
            r.raise_for_status()
            gif_page_html = await r.text()
            gif_info_match = re.search(r"<script class=\"dynamic\" type=\"application/ld\+json\">(.*?)</script>", gif_page_html)
            gif_info_raw = gif_info_match.group(1).strip() if gif_info_match else ""
            if not gif_info_raw:
                return url
            gif_info = json.loads(gif_info_raw)
            return gif_info['image']['contentUrl']
        except Exception:
            traceback.print_exc()
            return url
    else:
        return url