from __future__ import annotations

import asyncio
import logging
from typing import Callable

import httpx

log = logging.getLogger(__name__)


async def validate_proxies(
    proxy_urls: list[str],
    check_url: str,
    concurrency: int,
    timeout_seconds: float,
    on_progress: Callable[[int, int], None] | None = None,
) -> list[str]:
    sem = asyncio.Semaphore(max(1, concurrency))
    ok: list[str] = []
    lock = asyncio.Lock()
    total = len(proxy_urls)
    done = 0

    async def one(u: str) -> None:
        nonlocal done
        async with sem:
            good = await _check_one(u, check_url, timeout_seconds)
        async with lock:
            done += 1
            if good:
                ok.append(u)
            if on_progress:
                on_progress(done, total)

    await asyncio.gather(*(one(u) for u in proxy_urls))
    return ok


async def _check_one(proxy_url: str, check_url: str, timeout_seconds: float) -> bool:
    try:
        t = httpx.Timeout(timeout_seconds, connect=min(8.0, timeout_seconds))
        async with httpx.AsyncClient(proxy=proxy_url, timeout=t, verify=True, follow_redirects=True) as c:
            r = await c.get(check_url)
            return r.status_code == 200 and len(r.content) > 0
    except Exception:
        return False


async def check_chain_exit_ip(
    listen_proxy: str, check_url: str, timeout_seconds: float
) -> str | None:
    """Query the IP-check URL through the local chain proxy.
    Returns the exit IP string on success, or None on failure."""
    try:
        t = httpx.Timeout(timeout_seconds, connect=min(10.0, timeout_seconds))
        async with httpx.AsyncClient(proxy=listen_proxy, timeout=t, verify=True, follow_redirects=True) as c:
            r = await c.get(check_url)
            if r.status_code != 200:
                return None
            body = r.text.strip()
            # ipify returns {"ip":"x.x.x.x"} in json mode
            if body.startswith("{"):
                import json
                try:
                    return json.loads(body).get("ip") or json.loads(body).get("origin")
                except Exception:
                    return None
            # plain text mode
            if body and len(body) < 50:
                return body
            return None
    except Exception:
        return None


async def get_direct_ip(check_url: str, timeout_seconds: float = 15.0) -> str | None:
    """Get our own exit IP without the proxy chain (so we can compare)."""
    try:
        t = httpx.Timeout(timeout_seconds)
        async with httpx.AsyncClient(timeout=t, verify=True, follow_redirects=True) as c:
            r = await c.get(check_url)
            if r.status_code != 200:
                return None
            body = r.text.strip()
            if body.startswith("{"):
                import json
                try:
                    return json.loads(body).get("ip") or json.loads(body).get("origin")
                except Exception:
                    return None
            if body and len(body) < 50:
                return body
            return None
    except Exception:
        return None