# terabox_utils.py

import re
import requests
import asyncio
from functools import partial
import logging
import os
import time
import math
import subprocess
from typing import Optional, Tuple

import config

logger = logging.getLogger(__name__)
os.makedirs("downloads", exist_ok=True)

# --- Utility Functions ---
def format_bytes(size_bytes: int) -> str:
    if size_bytes <= 0:
        return "0 B"
    size_name = ("B", "KB", "MB", "GB", "TB")
    i = min(int(math.log(size_bytes, 1024)), len(size_name) - 1)
    p = math.pow(1024, i)
    s = round(size_bytes / p, 2)
    return f"{s} {size_name[i]}"

async def extract_terabox_short_id(full_url: str) -> Optional[str]:
    patterns = [
        r'terabox\.com/s/([a-zA-Z0-9_-]+)',
        r'teraboxapp\.com/s/([a-zA-Z0-9_-]+)',
        r'1024tera\.com/s/([a-zA-Z0-9_-]+)',
        r'freeterabox\.com/s/([a-zA-Z0-9_-]+)',
        r'terabox\.com/sharing/link\?surl=([a-zA-Z0-9_-]+)',
        r'terasharelink\.com/s/([a-zA-Z0-9_-]+)',
        r'4funbox\.com/s/([a-zA-Z0-9_-]+)',
        r'box-links\.com/s/([a-zA-Z0-9_-]+)'
    ]
    for p in patterns:
        if m := re.search(p, full_url, re.I):
            return m.group(1)
    return None

# --- Main Link Extraction ---
async def get_final_url_and_filename(original_link: str) -> Tuple[Optional[str], Optional[str], Optional[str]]:
    # First, try WORKER API
    payload = {"link": original_link}
    headers = {"User-Agent": "Mozilla/5.0"}

    try:
        loop = asyncio.get_event_loop()
        r = await loop.run_in_executor(
            None,
            partial(requests.post, config.TERABOX_WORKER_URL, headers=headers, json=payload, timeout=30)
        )
        r.raise_for_status()
        data = r.json()

        dl = data.get("proxy_url")
        fn = data.get("file_name")

        if data.get("error") or not dl or not fn:
            return None, None, data.get('error', 'Worker returned incomplete data.')

        return dl, fn, None

    except Exception as e:
        logger.error(f"[Worker] Failed for {original_link} → {str(e)}")
        return None, None, f"Worker API failed: {str(e)}"

# --- Downloader ---
async def download_terabox_file(bot_instance, chat_id, msg_id, url, filename):
    safe_fn = re.sub(r'[\\/*?:"<>|]', "_", filename)[:200]
    raw_download_path = os.path.join("downloads", f"{chat_id}_{time.time()}_{safe_fn}")

    try:
        loop = asyncio.get_event_loop()

        headers = {
            "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36",
            "Accept": "*/*",
            "Referer": "https://teraboxapp.com/"
        }

        r = await loop.run_in_executor(
            None,
            partial(requests.get, url, headers=headers, stream=True, timeout=(10, 300), allow_redirects=True)
        )
        r.raise_for_status()

        total_size = int(r.headers.get('content-length', 0))
        dl_size = 0
        last_update = time.time()

        with open(raw_download_path, 'wb') as f:
            for chunk in r.iter_content(chunk_size=1024 * 1024):
                if chunk:
                    f.write(chunk)
                    dl_size += len(chunk)

                    if time.time() - last_update > 2.5:
                        pct = (dl_size / total_size * 100) if total_size > 0 else 0
                        prog_text = (
                            f"📥 **Downloading:** `{filename}`\n"
                            f"Progress: {format_bytes(dl_size)}/{format_bytes(total_size)} ({pct:.1f}%)"
                        )
                        try:
                            await bot_instance.edit_message_text(
                                chat_id, msg_id, prog_text, parse_mode="Markdown"
                            )
                        except Exception:
                            pass

                        last_update = time.time()

        # Now decide whether to convert
        if config.ENABLE_FFMPEG_CONVERT:
            # Optional ffmpeg convert (if ENABLE_FFMPEG_CONVERT = True)
            new_filename = os.path.splitext(safe_fn)[0] + "_converted.mp4"
            converted_path = os.path.join("downloads", f"{chat_id}_{time.time()}_{new_filename}")
            thumb_path = os.path.join("downloads", f"{chat_id}_{time.time()}_thumb.jpg")

            # Convert to mp4
            ffmpeg_convert_cmd = [
                "ffmpeg", "-y", "-i", raw_download_path,
                "-c:v", "libx264", "-preset", "fast", "-c:a", "aac",
                "-movflags", "+faststart", converted_path
            ]
            subprocess.run(ffmpeg_convert_cmd, check=True)

            # Generate thumbnail
            ffmpeg_thumb_cmd = [
                "ffmpeg", "-y", "-i", converted_path,
                "-ss", "00:00:01.000", "-vframes", "1", thumb_path
            ]
            subprocess.run(ffmpeg_thumb_cmd, check=True)

            # Cleanup raw file
            os.remove(raw_download_path)
            return converted_path, thumb_path, None
        else:
            # No conversion, return raw path
            return raw_download_path, None, None

    except Exception as e:
        if os.path.exists(raw_download_path):
            os.remove(raw_download_path)
        return None, None, str(e)