#!/usr/bin/env python3
"""
gemini-web2api - Gemini Web to OpenAI API proxy.

Converts Google Gemini's web interface into an OpenAI-compatible API server.
Uses curl_cffi for Chrome TLS fingerprint impersonation to avoid bot detection.

Usage:
    python gemini_web2api.py [--port 8081] [--config config.json]

Client configuration (Cherry Studio, ChatBox, etc.):
    Base URL: http://localhost:8081/v1
    API Key: Set via API_KEY environment variable (Hugging Face Secrets)
"""
import json
import urllib.request
import urllib.parse
import time
import ssl
import sys
import uuid
import re
import os
import random
import hashlib
import argparse
from http.server import HTTPServer, BaseHTTPRequestHandler
from socketserver import ThreadingMixIn
from collections import OrderedDict

__version__ = "2.0.0"

# ─── curl_cffi with fallback ────────────────────────────────────────────────
# curl_cffi provides Chrome TLS fingerprint impersonation, making requests
# indistinguishable from real Chrome browsers at the TLS layer.
# Falls back to stdlib urllib if not available (less stealthy).

try:
    from curl_cffi.requests import Session as CurlSession
    HAS_CURL_CFFI = True
except ImportError:
    HAS_CURL_CFFI = False
    CurlSession = None

# ─── Configuration ───────────────────────────────────────────────────────────

DEFAULT_CONFIG = {
    "port": 8081,
    "host": "0.0.0.0",
    "retry_attempts": 3,
    "retry_delay_sec": 2,
    "request_timeout_sec": 180,
    "gemini_bl": "boq_assistant-bard-web-server_20260525.09_p0",
    "default_model": "gemini-flash",
    "log_requests": True,
    "cookie_file": None,
    "proxy": None,
    "api_key": os.environ.get("API_KEY"),  # Set via Hugging Face Secrets
    # Chrome fingerprint settings
    "chrome_version": 124,
    "impersonate_target": "chrome124",
    # Request jitter (ms) - randomized delays to mimic human behavior
    "jitter_min_ms": 50,
    "jitter_max_ms": 300,
    "debug_mode": False,
}

CONFIG = dict(DEFAULT_CONFIG)

# ─── Models (synced from upstream xwteam/gemini2api v1.6.15) ─────────────────
# Model selection via x-goog-ext-525001261-jspb header with hex model IDs.
# This replaces the old integer mode category approach.

MODEL_HEADER_KEY = "x-goog-ext-525001261-jspb"

GEMINI_MODELS = {
    # Internal model name → routing info
    # think: 0 = thinking enabled (for thinking models), 4 = thinking disabled (for standard models)
    "gemini-3-pro": {
        "id": "9d8ca3786ebdfbea", "capacity": 1, "think": 4,
        "desc": "Pro model (free tier)",
    },
    "gemini-3-flash": {
        "id": "fbb127bbb056c959", "capacity": 1, "think": 4,
        "desc": "Fast general-purpose model",
    },
    "gemini-3-flash-thinking": {
        "id": "5bf011840784117a", "capacity": 1, "think": 0,
        "desc": "Deep thinking mode",
    },
    # Pro-only (paid tier) models
    "gemini-3-pro-plus": {
        "id": "e6fa609c3fa255c0", "capacity": 4, "think": 4,
        "desc": "Pro+ model (requires subscription)",
    },
    "gemini-3-flash-plus": {
        "id": "56fdd199312815e2", "capacity": 4, "think": 4,
        "desc": "Flash+ model (requires subscription)",
    },
    "gemini-3-flash-thinking-plus": {
        "id": "e051ce1aa80aa576", "capacity": 4, "think": 0,
        "desc": "Thinking+ model (requires subscription)",
    },
}

# Stable public model names (API contract - never change these)
# Maps public name → family → resolved to internal name
PUBLIC_MODELS = {
    "gemini-pro": {"family": "pro", "default": "gemini-3-pro",
                   "desc": "Pro model for complex tasks"},
    "gemini-flash": {"family": "flash", "default": "gemini-3-flash",
                     "desc": "Fast general-purpose model"},
    "gemini-flash-thinking": {"family": "flash-thinking", "default": "gemini-3-flash-thinking",
                              "desc": "Deep thinking with extended output"},
}

# Legacy model name aliases → stable public name
MODEL_ALIASES = {
    # Old names from your v1.0.0
    "gemini-3.5-flash": "gemini-flash",
    "gemini-3.5-flash-thinking": "gemini-flash-thinking",
    "gemini-3.5-flash-thinking-lite": "gemini-flash-thinking",
    "gemini-3.1-pro": "gemini-pro",
    "gemini-auto": "gemini-flash",
    "gemini-flash-lite": "gemini-flash",
    # Upstream aliases
    "gemini-2.5-pro": "gemini-pro",
    "gemini-2.5-flash": "gemini-flash",
    "gemini-2.5-flash-thinking": "gemini-flash-thinking",
    "gemini-2.5-pro-preview-05-06": "gemini-pro",
    "gemini-2.5-flash-preview-04-17": "gemini-flash",
    "gemini-2.5-flash-preview-05-20": "gemini-flash",
    "gemini-2.0-flash": "gemini-flash",
    "gemini-2.0-flash-thinking": "gemini-flash-thinking",
    "gemini-2.0-flash-lite": "gemini-flash",
    "gemini-1.5-pro": "gemini-pro",
    "gemini-1.5-flash": "gemini-flash",
}

# All model names exposed to clients (public names only for API stability)
EXPOSED_MODELS = PUBLIC_MODELS


def resolve_model(model_name: str) -> tuple:
    """Resolve any model name to (public_name, internal_name, model_info, error).

    Resolution chain:
      1. Legacy alias → public name
      2. Public name → internal name (via family default)
      3. Already an internal name → use directly
    """
    # Step 1: resolve aliases
    name = MODEL_ALIASES.get(model_name, model_name)

    # Step 2: if it's a public name, map to internal
    if name in PUBLIC_MODELS:
        pub = PUBLIC_MODELS[name]
        internal = pub["default"]
        info = GEMINI_MODELS.get(internal)
        if not info:
            return None, None, None, f"Internal model {internal} not found"
        return name, internal, info, None

    # Step 3: if it's already an internal name
    if name in GEMINI_MODELS:
        info = GEMINI_MODELS[name]
        # Find the public name for this internal model
        pub_name = name
        for pn, pv in PUBLIC_MODELS.items():
            if pv["default"] == name:
                pub_name = pn
                break
        return pub_name, name, info, None

    return None, None, None, f"Unknown model: {model_name}. Available: {', '.join(PUBLIC_MODELS.keys())}"


def build_model_headers(model_info: dict) -> dict:
    """Build the x-goog-ext headers for model selection."""
    if not model_info:
        return {}
    return {
        MODEL_HEADER_KEY: f'[1,null,null,null,"{model_info["id"]}",null,null,0,[4],null,null,{model_info["capacity"]}]',
        "x-goog-ext-73010989-jspb": "[0]",
        "x-goog-ext-73010990-jspb": "[0]",
    }


# ─── Utilities ───────────────────────────────────────────────────────────────

def log(msg: str):
    if CONFIG["log_requests"]:
        sys.stderr.write(f"[{time.strftime('%H:%M:%S')}] {msg}\n")
        sys.stderr.flush()


def apply_jitter():
    """Random delay to mimic human behavior."""
    delay = random.uniform(CONFIG["jitter_min_ms"], CONFIG["jitter_max_ms"]) / 1000.0
    time.sleep(delay)


def load_cookie() -> tuple:
    """Load cookie from file. Returns (cookie_str, sapisid)."""
    cookie_file = CONFIG.get("cookie_file")
    if not cookie_file:
        return "", None
    if not os.path.exists(cookie_file):
        return "", None
    try:
        with open(cookie_file, "r") as f:
            content = f.read().strip()
        if content.startswith("{"):
            data = json.loads(content)
            cookie_str = data.get("cookie", "")
            sapisid = data.get("sapisid", "")
        else:
            cookie_str = content
            pairs = dict(p.split("=", 1) for p in cookie_str.split("; ") if "=" in p)
            sapisid = pairs.get("SAPISID", "")
        return cookie_str, sapisid if sapisid else None
    except Exception as e:
        log(f"Cookie load error: {e}")
        return "", None


def make_sapisidhash(sapisid: str) -> str:
    ts = int(time.time())
    h = hashlib.sha1(f"{ts} {sapisid} https://gemini.google.com".encode()).hexdigest()
    return f"SAPISIDHASH {ts}_{h}"


# ─── Chrome-like Request Headers ─────────────────────────────────────────────

def build_chrome_headers(method: str = "POST", content_type: str = None) -> OrderedDict:
    """Build Chrome-like request headers in the correct order.

    Chrome sends headers in a specific order that differs from Python defaults.
    Matching this order helps avoid fingerprint-based detection.
    """
    ver = CONFIG["chrome_version"]
    headers = OrderedDict()

    # Chrome header order (important for fingerprint matching)
    headers["Host"] = "gemini.google.com"

    if content_type:
        headers["Content-Type"] = content_type

    headers["Sec-Ch-Ua"] = f'"Chromium";v="{ver}", "Google Chrome";v="{ver}", "Not-A.Brand";v="99"'
    headers["Sec-Ch-Ua-Mobile"] = "?0"
    headers["Sec-Ch-Ua-Platform"] = '"Windows"'

    headers["User-Agent"] = (
        f"Mozilla/5.0 (Windows NT 10.0; Win64; x64) "
        f"AppleWebKit/537.36 (KHTML, like Gecko) "
        f"Chrome/{ver}.0.0.0 Safari/537.36"
    )

    headers["X-Same-Domain"] = "1"
    headers["Origin"] = "https://gemini.google.com"
    headers["Referer"] = "https://gemini.google.com/app"

    # Sec-Fetch headers (differ by method)
    if method == "POST":
        headers["Sec-Fetch-Site"] = "same-origin"
        headers["Sec-Fetch-Mode"] = "cors"
        headers["Sec-Fetch-Dest"] = "empty"
    else:
        headers["Sec-Fetch-Site"] = "same-origin"
        headers["Sec-Fetch-Mode"] = "navigate"
        headers["Sec-Fetch-Dest"] = "document"
        headers["Sec-Fetch-User"] = "?1"

    headers["Accept-Language"] = "en-US,en;q=0.9"
    headers["Accept"] = "*/*"

    return headers


# ─── HTTP Transport Layer ────────────────────────────────────────────────────

class GeminiHTTPClient:
    """HTTP client with Chrome TLS fingerprint impersonation.

    Uses curl_cffi when available for real Chrome TLS fingerprints.
    Falls back to urllib.request (less stealthy but functional).
    """

    def __init__(self):
        self._session = None
        if HAS_CURL_CFFI:
            target = CONFIG.get("impersonate_target", "chrome124")
            self._session = CurlSession(
                impersonate=target,
                timeout=CONFIG["request_timeout_sec"],
            )
            log(f"HTTP transport: curl_cffi (impersonating {target})")
        else:
            log("HTTP transport: urllib (no TLS fingerprinting - less stealthy)")

    def get(self, url: str, headers: dict = None, cookies: dict = None) -> str:
        """GET request with Chrome fingerprint. Returns response text."""
        if self._session:
            return self._get_curl(url, headers, cookies)
        else:
            return self._get_urllib(url, headers, cookies)

    def _get_curl(self, url: str, headers: dict = None, cookies: dict = None) -> str:
        self._session.cookies.clear()
        proxy = CONFIG.get("proxy")
        proxies = {"http": proxy, "https": proxy} if proxy else None
        resp = self._session.get(
            url,
            headers=dict(headers) if headers else {},
            cookies=cookies or {},
            proxies=proxies,
            allow_redirects=True,
        )
        if resp.status_code != 200:
            raise Exception(f"HTTP {resp.status_code}: {resp.text[:200]}")
        return resp.text

    def _get_urllib(self, url: str, headers: dict = None, cookies: dict = None) -> str:
        all_headers = dict(headers) if headers else {}
        if cookies:
            cookie_str = "; ".join(f"{k}={v}" for k, v in cookies.items())
            existing = all_headers.get("Cookie", "")
            if existing:
                all_headers["Cookie"] = existing + "; " + cookie_str
            else:
                all_headers["Cookie"] = cookie_str
        req = urllib.request.Request(url, headers=all_headers, method="GET")
        ctx = ssl.create_default_context()
        proxy = CONFIG.get("proxy")
        if proxy:
            opener = urllib.request.build_opener(
                urllib.request.ProxyHandler({"http": proxy, "https": proxy}),
                urllib.request.HTTPSHandler(context=ctx)
            )
            urllib.request.install_opener(opener)
        else:
            opener = urllib.request.build_opener(urllib.request.HTTPSHandler(context=ctx))
            urllib.request.install_opener(opener)
        try:
            with urllib.request.urlopen(req, timeout=CONFIG["request_timeout_sec"]) as resp:
                return resp.read().decode("utf-8")
        except urllib.error.HTTPError as e:
            raise Exception(f"HTTP {e.code}: {e.read().decode('utf-8')[:200]}")

    def post(self, url: str, data: bytes, headers: dict, cookies: dict = None) -> str:
        """POST request with Chrome fingerprint. Returns response text."""
        if self._session:
            return self._post_curl(url, data, headers, cookies)
        else:
            return self._post_urllib(url, data, headers, cookies)

    def _post_curl(self, url: str, data: bytes, headers: dict, cookies: dict = None) -> str:
        """POST via curl_cffi with Chrome TLS impersonation."""
        # Clear internal cookie jar to prevent cross-domain cookie conflicts
        # (same fix as upstream: google.com / gemini.google.com / accounts.google.com)
        self._session.cookies.clear()

        proxy = CONFIG.get("proxy")
        proxies = {"http": proxy, "https": proxy} if proxy else None

        resp = self._session.post(
            url,
            data=data,
            headers=dict(headers),  # curl_cffi needs plain dict
            cookies=cookies or {},
            proxies=proxies,
            allow_redirects=True,
        )

        if resp.status_code != 200:
            raise Exception(f"HTTP {resp.status_code}: {resp.text[:200]}")

        return resp.text

    def _post_urllib(self, url: str, data: bytes, headers: dict, cookies: dict = None) -> str:
        """Fallback POST via urllib (no TLS fingerprinting)."""
        # Merge cookies into headers
        all_headers = dict(headers)
        if cookies:
            cookie_str = "; ".join(f"{k}={v}" for k, v in cookies.items())
            existing = all_headers.get("Cookie", "")
            if existing:
                all_headers["Cookie"] = existing + "; " + cookie_str
            else:
                all_headers["Cookie"] = cookie_str

        req = urllib.request.Request(url, data=data, headers=all_headers, method="POST")
        ctx = ssl.create_default_context()
        proxy = CONFIG.get("proxy")
        if proxy:
            opener = urllib.request.build_opener(
                urllib.request.ProxyHandler({"http": proxy, "https": proxy}),
                urllib.request.HTTPSHandler(context=ctx)
            )
            resp = opener.open(req, timeout=CONFIG["request_timeout_sec"])
        else:
            resp = urllib.request.urlopen(req, context=ctx, timeout=CONFIG["request_timeout_sec"])

        return resp.read().decode("utf-8", errors="replace")

    def post_stream(self, url: str, data: bytes, headers: dict, cookies: dict = None):
        """POST request that yields streaming chunks."""
        if self._session:
            return self._post_curl_stream(url, data, headers, cookies)
        else:
            return self._post_urllib_stream(url, data, headers, cookies)

    def _post_curl_stream(self, url: str, data: bytes, headers: dict, cookies: dict = None):
        self._session.cookies.clear()
        proxy = CONFIG.get("proxy")
        proxies = {"http": proxy, "https": proxy} if proxy else None
        
        resp = self._session.post(
            url,
            data=data,
            headers=dict(headers),
            cookies=cookies or {},
            proxies=proxies,
            allow_redirects=True,
            stream=True
        )
        if resp.status_code != 200:
            raise Exception(f"HTTP {resp.status_code}")
            
        for line in resp.iter_lines():
            if line:
                yield line.decode("utf-8", errors="replace")

    def _post_urllib_stream(self, url: str, data: bytes, headers: dict, cookies: dict = None):
        all_headers = dict(headers)
        if cookies:
            cookie_str = "; ".join(f"{k}={v}" for k, v in cookies.items())
            existing = all_headers.get("Cookie", "")
            if existing:
                all_headers["Cookie"] = existing + "; " + cookie_str
            else:
                all_headers["Cookie"] = cookie_str

        req = urllib.request.Request(url, data=data, headers=all_headers, method="POST")
        ctx = ssl.create_default_context()
        proxy = CONFIG.get("proxy")
        if proxy:
            opener = urllib.request.build_opener(
                urllib.request.ProxyHandler({"http": proxy, "https": proxy}),
                urllib.request.HTTPSHandler(context=ctx)
            )
            resp = opener.open(req, timeout=CONFIG["request_timeout_sec"])
        else:
            resp = urllib.request.urlopen(req, context=ctx, timeout=CONFIG["request_timeout_sec"])
            
        for line in resp:
            if line:
                yield line.decode("utf-8", errors="replace")

    def close(self):
        if self._session:
            try:
                self._session.close()
            except Exception:
                pass


# Global HTTP client (initialized in main)
_http_client: GeminiHTTPClient = None


def get_http_client() -> GeminiHTTPClient:
    global _http_client
    if _http_client is None:
        _http_client = GeminiHTTPClient()
    return _http_client


# ─── Gemini Protocol ─────────────────────────────────────────────────────────

def gemini_stream_generate(prompt: str, model_info: dict, stream: bool = False):
    """Send prompt to Gemini StreamGenerate with retry.

    Uses the x-goog-ext-525001261-jspb header for model selection
    (upstream approach) instead of the old integer mode category.
    """
    # Build the inner payload array
    # The payload structure is from Gemini's batchexecute protocol
    inner = [None] * 80
    inner[0] = [prompt, 0, None, None, None, None, 0]
    inner[1] = ["en"]
    inner[2] = ["", "", "", None, None, None, None, None, None, ""]
    inner[6] = [0]
    inner[7] = 1
    inner[10] = 1
    inner[11] = 0
    # Think mode: 0 = thinking enabled, 4 = thinking disabled
    # Each model carries its own think value
    think_mode = model_info.get("think", 4)
    inner[17] = [[think_mode]]
    inner[18] = 0
    inner[27] = 1
    inner[30] = [4]
    inner[41] = [2]
    inner[53] = 0
    inner[59] = str(uuid.uuid4())
    inner[61] = []
    inner[68] = 1
    # Model is now set via HTTP header, not payload slot 79
    # inner[79] is left as None

    outer = [None, json.dumps(inner)]
    body = urllib.parse.urlencode({"f.req": json.dumps(outer)}).encode()
    reqid = random.randint(10000, 99999)
    url = (
        "https://gemini.google.com/_/BardChatUi/data/"
        "assistant.lamda.BardFrontendService/StreamGenerate"
        f"?bl={CONFIG['gemini_bl']}&hl=en&_reqid={reqid}&rt=c"
    )

    # Build Chrome-like headers
    headers = build_chrome_headers(
        method="POST",
        content_type="application/x-www-form-urlencoded",
    )

    # Add model selection headers
    model_headers = build_model_headers(model_info)
    headers.update(model_headers)

    # Load and apply cookie
    cookie_str, sapisid = load_cookie()
    cookies = {}
    if cookie_str:
        # Parse cookie string into dict for curl_cffi
        for pair in cookie_str.split("; "):
            if "=" in pair:
                k, v = pair.split("=", 1)
                cookies[k.strip()] = v.strip()
        # Also set as header for urllib fallback
        headers["Cookie"] = cookie_str
    if sapisid:
        headers["Authorization"] = make_sapisidhash(sapisid)

    client = get_http_client()
    last_err = None
    for attempt in range(CONFIG["retry_attempts"]):
        try:
            # Apply request jitter to mimic human behavior
            if attempt > 0:
                time.sleep(CONFIG["retry_delay_sec"])
            apply_jitter()

            if stream:
                return client.post_stream(url, data=body, headers=headers, cookies=cookies)
            else:
                return client.post(url, data=body, headers=headers, cookies=cookies)
        except Exception as e:
            last_err = e
            if attempt < CONFIG["retry_attempts"] - 1:
                log(f"Retry {attempt+1}/{CONFIG['retry_attempts']}: {e}")
    raise last_err


def clean_gemini_text(text: str) -> str:
    """Remove internal code execution artifacts and image placeholders."""
    # Convert code execution blocks to standard markdown
    text = re.sub(
        r'\?code_(?:reference|stdout)&code_event_index=\d+',
        '', text
    )
    # Remove googleusercontent placeholder URLs (image gen/retrieval/collection)
    text = re.sub(
        r'https?://googleusercontent\.com/(?:image_generation_content|image_retrieval|image_collection)[/\w]*\d*',
        '', text
    )
    return text


def _scan_complete_wrb_frames(buf: str) -> list:
    """Extract complete wrb.fr frames using bracket-depth scanning.

    This is the upstream's improved parser that correctly handles
    partial chunks and escape sequences, replacing the old line-by-line approach.
    """
    frames = []
    i = 0
    n = len(buf)
    while i < n:
        start = buf.find('["wrb.fr"', i)
        if start == -1:
            break
        # Bracket-depth scan to find matching close bracket
        depth = 0
        in_str = False
        esc = False
        end = -1
        j = start
        while j < n:
            c = buf[j]
            if in_str:
                if esc:
                    esc = False
                elif c == '\\':
                    esc = True
                elif c == '"':
                    in_str = False
            else:
                if c == '"':
                    in_str = True
                elif c == '[':
                    depth += 1
                elif c == ']':
                    depth -= 1
                    if depth == 0:
                        end = j
                        break
            j += 1
        if end == -1:
            break  # Incomplete frame
        elem_str = buf[start:end + 1]
        try:
            elem = json.loads(elem_str)
            frames.append(elem)
        except (json.JSONDecodeError, ValueError):
            pass
        i = end + 1
    return frames


def gemini_stream_parse(stream_generator, model_info: dict = None):
    """Consume network chunks, parse wrb.fr frames, and yield text deltas incrementally."""
    buf = ""
    emitted_raw = ""
    first_chunk = True
    
    for chunk in stream_generator:
        if not chunk: continue
        buf += chunk
        
        frames = _scan_complete_wrb_frames(buf)
        if not frames: continue
        
        # In stream context, the parser needs to extract the latest text
        texts = []
        for elem in frames:
            try:
                if not isinstance(elem, list) or len(elem) < 3 or elem[0] != "wrb.fr":
                    continue
                rp = elem[2]
                if not isinstance(rp, str) or len(rp) < 50:
                    continue
                payload = json.loads(rp)
                
                if isinstance(payload, list) and len(payload) > 4 and payload[4]:
                    for part in payload[4]:
                        if isinstance(part, list) and len(part) > 1 and part[1]:
                            if isinstance(part[1], list):
                                for t in part[1]:
                                    if isinstance(t, str) and len(t) > 0:
                                        texts.append(t)
            except (json.JSONDecodeError, IndexError, TypeError):
                pass

        current_full_text = ""
        for t in reversed(texts):
            if t.strip():
                current_full_text = t
                break
                
        if current_full_text == emitted_raw:
            continue
            
        if current_full_text.startswith(emitted_raw):
            raw_delta = current_full_text[len(emitted_raw):]
            emitted_raw = current_full_text
            
            if raw_delta:
                cleaned_delta = clean_gemini_text(raw_delta)
                first_chunk = False
                
                if cleaned_delta:
                    yield cleaned_delta

def extract_response_text(raw: str, model_info: dict = None) -> str:
    """Parse StreamGenerate response to extract final text. (Backwards compatible)"""
    gen = gemini_stream_parse([raw], model_info)
    return "".join(list(gen))


# ─── OpenAI Format Helpers ───────────────────────────────────────────────────

def messages_to_prompt(messages: list, tools: list = None) -> str:
    """Convert OpenAI messages to prompt string."""
    parts = []
    if tools:
        tool_defs = []
        for tool in tools:
            fn = tool.get("function", tool) if tool.get("type") == "function" else tool
            tool_defs.append({
                "name": fn.get("name", tool.get("name", "")),
                "description": fn.get("description", tool.get("description", "")),
                "parameters": fn.get("parameters", tool.get("parameters", {})),
            })
        if tool_defs:
            parts.append(
                "[System instruction]: You have access to tools. "
                "To call a tool, respond with:\n"
                '```tool_call\n{"name": "func_name", "arguments": {...}}\n```\n'
                "Only use tool_call blocks when needed.\n\n"
                f"Available tools:\n{json.dumps(tool_defs, indent=2)}"
            )
    for msg in messages:
        role = msg.get("role", "user")
        content = msg.get("content", "")
        if isinstance(content, list):
            content = " ".join(
                c.get("text", "") for c in content
                if c.get("type") in ("text", "input_text")
            )
        if role == "system":
            parts.append(f"[System instruction]: {content}")
        elif role == "assistant":
            if msg.get("tool_calls"):
                tc_strs = []
                for tc in msg["tool_calls"]:
                    fn = tc.get("function", {})
                    tc_strs.append(
                        f'```tool_call\n{{"name": "{fn.get("name")}", '
                        f'"arguments": {fn.get("arguments", "{}}")}}}\n```'
                    )
                parts.append(f"[Assistant]: {content or ''}\n" + "\n".join(tc_strs))
            else:
                parts.append(f"[Assistant]: {content}")
        elif role == "tool":
            parts.append(f"[Tool result for {msg.get('name', '')}]: {content}")
        else:
            parts.append(content if content else "")
    return "\n\n".join(p for p in parts if p)


def parse_tool_calls(text: str) -> tuple:
    """Extract tool_call blocks. Returns (clean_text, tool_calls_list)."""
    tool_calls = []
    pattern = r'```tool_call\s*\n(.*?)\n```'
    for match in re.findall(pattern, text, re.DOTALL):
        try:
            data = json.loads(match.strip())
            tool_calls.append({
                "id": f"call_{uuid.uuid4().hex[:8]}",
                "type": "function",
                "function": {
                    "name": data["name"],
                    "arguments": json.dumps(data.get("arguments", {}), ensure_ascii=False),
                },
            })
        except (json.JSONDecodeError, KeyError):
            pass
    clean = re.sub(pattern, '', text, flags=re.DOTALL).strip()
    return clean, tool_calls


# ─── HTTP Handler ────────────────────────────────────────────────────────────

class GeminiHandler(BaseHTTPRequestHandler):
    def log_message(self, fmt, *args):
        log(fmt % args)

    def validate_api_key(self) -> bool:
        """Validate the API key from Authorization header against configured key.
        Returns True if valid or if no API key is configured (open access)."""
        configured_key = CONFIG.get("api_key")
        if not configured_key:
            return True  # No key configured = open access
        auth_header = self.headers.get("Authorization", "")
        if auth_header.startswith("Bearer "):
            provided_key = auth_header[7:].strip()
        else:
            provided_key = auth_header.strip()
        if provided_key == configured_key:
            return True
        log(f"API key rejected from {self.client_address[0]}")
        self.send_json(
            {"error": {"message": "Invalid API key. Provide a valid key via 'Authorization: Bearer <key>' header.",
                       "type": "authentication_error", "code": "invalid_api_key"}}, 401)
        return False

    def send_json(self, data, status=200):
        body = json.dumps(data, ensure_ascii=False).encode()
        self.send_response(status)
        self.send_header("Content-Type", "application/json")
        self.send_header("Access-Control-Allow-Origin", "*")
        self.send_header("Content-Length", str(len(body)))
        self.end_headers()
        self.wfile.write(body)

    def do_OPTIONS(self):
        self.send_response(204)
        self.send_header("Access-Control-Allow-Origin", "*")
        self.send_header("Access-Control-Allow-Methods", "GET, POST, OPTIONS")
        self.send_header("Access-Control-Allow-Headers", "*")
        self.end_headers()

    def do_GET(self):
        try:
            if self.path == "/v1/models":
                if not self.validate_api_key():
                    return
                self.send_json({"object": "list", "data": [
                    {"id": n, "object": "model", "created": 1700000000,
                     "owned_by": "google", "description": c["desc"]}
                    for n, c in EXPOSED_MODELS.items()
                ]})
            elif self.path == "/":
                self.send_json({
                    "status": "ok",
                    "version": __version__,
                    "transport": "curl_cffi" if HAS_CURL_CFFI else "urllib",
                    "models": list(EXPOSED_MODELS.keys()),
                    "aliases": list(MODEL_ALIASES.keys()),
                })
            else:
                self.send_json({"error": "not found"}, 404)
        except (BrokenPipeError, ConnectionResetError):
            pass
        except Exception as e:
            log(f"GET error: {e}")

    def do_POST(self):
        try:
            if not self.validate_api_key():
                return
            
            if self.headers.get("Transfer-Encoding", "").lower() == "chunked":
                body = b""
                while True:
                    line = self.rfile.readline().strip()
                    if not line:
                        break
                    chunk_size = int(line, 16)
                    if chunk_size == 0:
                        self.rfile.readline() # Read trailing \r\n
                        break
                    body += self.rfile.read(chunk_size)
                    self.rfile.readline() # Read trailing \r\n
            else:
                length = int(self.headers.get("Content-Length", 0))
                body = self.rfile.read(length) if length else b""
                
            if self.path == "/v1/chat/completions":
                self.handle_chat(body)
            elif self.path == "/v1/responses":
                self.handle_responses(body)
            else:
                self.send_json({"error": "not found"}, 404)
        except (BrokenPipeError, ConnectionResetError):
            pass
        except Exception as e:
            log(f"POST error: {e}")
            try:
                self.send_json({"error": {"message": str(e)}}, 500)
            except:
                pass

    def _resolve_model(self, model_name):
        pub_name, internal_name, model_info, err = resolve_model(model_name)
        if err:
            return None, None, err
        return pub_name, model_info, None

    def _call_gemini(self, prompt, model_info, tools, stream=False):
        raw = gemini_stream_generate(prompt, model_info, stream=stream)
        if stream:
            return gemini_stream_parse(raw, model_info)
        else:
            text = extract_response_text(raw, model_info)
            tool_calls = None
            if tools and text:
                text, tool_calls = parse_tool_calls(text)
            return text or "", tool_calls

    def handle_chat(self, body: bytes):
        try:
            req = json.loads(body)
            if CONFIG.get("debug_mode"):
                log(f"DEBUG [CHAT] REQUEST: {json.dumps(req, ensure_ascii=False)[:2000]}")
        except json.JSONDecodeError as e:
            self.send_json({"error": {"message": f"Invalid JSON payload: {e}. Body received: {body.decode('utf-8', errors='replace')}"}}, 400)
            return
        model_name, model_info, err = self._resolve_model(
            req.get("model", CONFIG["default_model"]))
        if err:
            self.send_json({"error": {"message": err}}, 400)
            return

        tools = req.get("tools")
        if CONFIG.get("debug_mode"):
            think_status = "Enabled" if model_info.get("think") == 0 else "Disabled"
            log(f"DEBUG [CHAT] MODEL: {model_name} (Think Mode: {think_status})")
            if tools:
                log(f"DEBUG [CHAT] TOOLS PROVIDED: {len(tools)} tools")
                
        prompt = messages_to_prompt(req.get("messages", []), tools)
        if not prompt.strip():
            self.send_json({"error": {"message": "empty prompt"}}, 400)
            return

        is_stream = bool(req.get("stream"))
        
        try:
            # If tools are provided, we must collect full text first to parse them, so disable network streaming
            if tools:
                text, tool_calls = self._call_gemini(prompt, model_info, tools, stream=False)
                if CONFIG.get("debug_mode"):
                    log(f"DEBUG [CHAT] RESPONSE TEXT: {text}")
                    log(f"DEBUG [CHAT] RESPONSE TOOLS: {tool_calls}")
            else:
                result = self._call_gemini(prompt, model_info, tools, stream=is_stream)
                if not is_stream and CONFIG.get("debug_mode"):
                    log(f"DEBUG [CHAT] RESPONSE: {result}")
        except Exception as e:
            self.send_json({"error": {"message": f"upstream error: {e}"}}, 502)
            return

        cid = f"chatcmpl-{uuid.uuid4().hex[:12]}"
        
        if is_stream:
            self.send_response(200)
            self.send_header("Content-Type", "text/event-stream")
            self.send_header("Cache-Control", "no-cache")
            self.send_header("Access-Control-Allow-Origin", "*")
            self.end_headers()
            
            if tools:
                # Tools were present, so we ran synchronously. We yield the tool calls in streaming format.
                if tool_calls:
                    for tc in tool_calls:
                        chunk = {"id": cid, "object": "chat.completion.chunk", "created": int(time.time()),
                                 "model": model_name, "choices": [{"index": 0, "delta": {"tool_calls": [tc]}}]}
                        self.wfile.write(f"data: {json.dumps(chunk)}\n\n".encode())
                    chunk = {"id": cid, "object": "chat.completion.chunk", "created": int(time.time()),
                             "model": model_name, "choices": [{"index": 0, "delta": {}, "finish_reason": "tool_calls"}]}
                    self.wfile.write(f"data: {json.dumps(chunk)}\n\n".encode())
                else:
                    msg = {"role": "assistant", "content": text or ""}
                    chunk = {"id": cid, "object": "chat.completion.chunk", "created": int(time.time()),
                             "model": model_name, "choices": [{"index": 0, "delta": msg, "finish_reason": "stop"}]}
                    self.wfile.write(f"data: {json.dumps(chunk)}\n\n".encode())
            else:
                # Real streaming
                first = True
                for delta in result:
                    if CONFIG.get("debug_mode") and delta:
                        log(f"DEBUG [CHAT] CHUNK: {delta}")
                    msg = {"role": "assistant"} if first else {}
                    if delta: msg["content"] = delta
                    first = False
                    chunk = {"id": cid, "object": "chat.completion.chunk", "created": int(time.time()),
                             "model": model_name, "choices": [{"index": 0, "delta": msg, "finish_reason": None}]}
                    self.wfile.write(f"data: {json.dumps(chunk)}\n\n".encode())
                    self.wfile.flush()
                
                chunk = {"id": cid, "object": "chat.completion.chunk", "created": int(time.time()),
                         "model": model_name, "choices": [{"index": 0, "delta": {}, "finish_reason": "stop"}]}
                self.wfile.write(f"data: {json.dumps(chunk)}\n\n".encode())
            
            self.wfile.write(b"data: [DONE]\n\n")
            self.wfile.flush()
        else:
            if tools:
                msg = {"role": "assistant", "content": text or None}
                if tool_calls:
                    msg["tool_calls"] = tool_calls
                finish = "tool_calls" if tool_calls else "stop"
            else:
                msg = {"role": "assistant", "content": result or None}
                finish = "stop"
                
            self.send_json({
                "id": cid, "object": "chat.completion", "created": int(time.time()),
                "model": model_name,
                "choices": [{"index": 0, "message": msg, "finish_reason": finish}],
                "usage": {"prompt_tokens": len(prompt)//4, "completion_tokens": 0,
                          "total_tokens": len(prompt)//4},
            })

    def handle_responses(self, body: bytes):
        """OpenAI Responses API for Codex CLI compatibility."""
        try:
            req = json.loads(body)
            if CONFIG.get("debug_mode"):
                log(f"DEBUG [RESP] REQUEST: {json.dumps(req, ensure_ascii=False)[:2000]}")
        except json.JSONDecodeError as e:
            self.send_json({"error": {"message": f"Invalid JSON payload: {e}. Body received: {body.decode('utf-8', errors='replace')}"}}, 400)
            return
        model_name, model_info, err = self._resolve_model(
            req.get("model", CONFIG["default_model"]))
        if err:
            self.send_json({"error": {"message": err}}, 400)
            return

        input_items = req.get("input", [])
        tools = req.get("tools")
        
        if CONFIG.get("debug_mode"):
            think_status = "Enabled" if model_info.get("think") == 0 else "Disabled"
            log(f"DEBUG [RESP] MODEL: {model_name} (Think Mode: {think_status})")
            if tools:
                log(f"DEBUG [RESP] TOOLS PROVIDED: {len(tools)} tools")

        messages = []
        if req.get("instructions"):
            messages.append({"role": "system", "content": req["instructions"]})
        if isinstance(input_items, str):
            messages.append({"role": "user", "content": input_items})
        elif isinstance(input_items, list):
            for item in input_items:
                if isinstance(item, str):
                    messages.append({"role": "user", "content": item})
                elif isinstance(item, dict):
                    if item.get("type") == "function_call_output":
                        messages.append({"role": "tool", "tool_call_id": item.get("call_id", ""),
                                         "name": item.get("name", ""), "content": item.get("output", "")})
                    elif item.get("role") == "assistant" or (item.get("type") == "message" and item.get("role") == "assistant"):
                        cp = item.get("content", [])
                        text_acc, tc_list = "", []
                        if isinstance(cp, list):
                            for c in cp:
                                if isinstance(c, dict):
                                    if c.get("type") == "output_text": text_acc += c.get("text", "")
                                    elif c.get("type") == "function_call": tc_list.append(c)
                        elif isinstance(cp, str):
                            text_acc = cp
                        m = {"role": "assistant", "content": text_acc or None}
                        if tc_list:
                            m["tool_calls"] = [{"id": tc.get("call_id", f"call_{i}"), "type": "function",
                                                "function": {"name": tc.get("name",""), "arguments": tc.get("arguments","{}")}}
                                               for i, tc in enumerate(tc_list)]
                        messages.append(m)
                    else:
                        role = item.get("role", "user")
                        content = item.get("content", "")
                        if isinstance(content, list):
                            content = " ".join(c.get("text", "") for c in content if c.get("type") in ("text", "input_text"))
                        messages.append({"role": role, "content": content})

        if tools:
            tools = [{"type": "function", "function": {"name": t["name"], "description": t.get("description", ""), "parameters": t.get("parameters", {})}}
                     if t.get("type") == "function" and "function" not in t else t for t in tools]

        prompt = messages_to_prompt(messages, tools)
        if not prompt.strip():
            self.send_json({"error": {"message": "empty input"}}, 400)
            return

        try:
            text, tool_calls = self._call_gemini(prompt, model_info, tools)
            if CONFIG.get("debug_mode"):
                log(f"DEBUG [RESP] RESPONSE TEXT: {text}")
                log(f"DEBUG [RESP] RESPONSE TOOLS: {tool_calls}")
        except Exception as e:
            self.send_json({"error": {"message": f"upstream error: {e}"}}, 502)
            return

        rid = f"resp_{uuid.uuid4().hex[:16]}"
        mid = f"msg_{uuid.uuid4().hex[:12]}"
        output = []
        if tool_calls:
            for tc in tool_calls:
                output.append({"type": "function_call", "id": tc["id"], "call_id": tc["id"],
                               "name": tc["function"]["name"], "arguments": tc["function"]["arguments"], "status": "completed"})
        if text or not tool_calls:
            output.append({"type": "message", "id": mid, "role": "assistant", "status": "completed",
                           "content": [{"type": "output_text", "text": text or "", "annotations": []}]})

        if req.get("stream"):
            self.send_response(200)
            self.send_header("Content-Type", "text/event-stream")
            self.send_header("Cache-Control", "no-cache")
            self.send_header("Access-Control-Allow-Origin", "*")
            self.end_headers()
            ev = {"type": "response.created", "response": {"id": rid, "object": "response", "status": "in_progress", "model": model_name, "output": []}}
            self.wfile.write(f"event: response.created\ndata: {json.dumps(ev)}\n\n".encode())
            for item in output:
                if item["type"] == "function_call":
                    ev = {"type": "response.function_call_arguments.done", "item_id": item["id"], "call_id": item["call_id"], "name": item["name"], "arguments": item["arguments"]}
                    self.wfile.write(f"event: response.function_call_arguments.done\ndata: {json.dumps(ev)}\n\n".encode())
                elif item["type"] == "message":
                    for ci, cp in enumerate(item["content"]):
                        ev = {"type": "response.output_text.done", "item_id": item["id"], "content_index": ci, "text": cp["text"]}
                        self.wfile.write(f"event: response.output_text.done\ndata: {json.dumps(ev)}\n\n".encode())
            resp_obj = {"id": rid, "object": "response", "status": "completed", "model": model_name, "output": output,
                        "usage": {"input_tokens": len(prompt)//4, "output_tokens": len(text)//4, "total_tokens": (len(prompt)+len(text))//4}}
            self.wfile.write(f"event: response.completed\ndata: {json.dumps({'type': 'response.completed', 'response': resp_obj})}\n\n".encode())
            self.wfile.flush()
        else:
            self.send_json({"id": rid, "object": "response", "created_at": int(time.time()), "status": "completed",
                            "model": model_name, "output": output,
                            "usage": {"input_tokens": len(prompt)//4, "output_tokens": len(text)//4, "total_tokens": (len(prompt)+len(text))//4}})


# ─── Main ────────────────────────────────────────────────────────────────────

def load_config(path: str):
    if path and os.path.exists(path):
        with open(path) as f:
            CONFIG.update(json.load(f))
        log(f"Config loaded: {path}")


def update_gemini_bl():
    """Scrape the gemini.google.com homepage to extract the latest gemini_bl parameter."""
    try:
        log("Fetching latest gemini_bl parameter from gemini.google.com...")
        client = get_http_client()
        headers = build_chrome_headers(method="GET")
        html = client.get("https://gemini.google.com/app", headers=headers)
        
        # Look for the bl string in the HTML (usually under cfb2h or SNlM0e)
        match = re.search(r'"cfb2h":"([^"]+)"', html)
        if not match:
            match = re.search(r'"SNlM0e":"([^"]+)"', html)
            
        if match:
            CONFIG["gemini_bl"] = match.group(1)
            log(f"Successfully updated gemini_bl to: {CONFIG['gemini_bl']}")
        else:
            log("Warning: Could not extract gemini_bl from homepage. Using fallback.")
    except Exception as e:
        log(f"Error fetching gemini_bl: {e}. Using fallback.")


def main():
    parser = argparse.ArgumentParser(description="Gemini Web to OpenAI API")
    parser.add_argument("--port", type=int, default=None)
    parser.add_argument("--config", type=str, default=None)
    parser.add_argument("--cookie-file", type=str, default=None, help="Path to cookie file")
    parser.add_argument("--proxy", type=str, default=None, help="HTTP proxy, e.g. http://127.0.0.1:7890")
    parser.add_argument("--debug", action="store_true", help="Enable debug logging of requests/responses")
    parser.add_argument("--version", action="version", version=f"gemini-web2api {__version__}")
    args = parser.parse_args()

    config_path = args.config or os.environ.get("GEMINI_WEB2API_CONFIG")
    if not config_path:
        for p in ["./config.json", os.path.expanduser("~/.config/gemini-web2api/config.json")]:
            if os.path.exists(p):
                config_path = p
                break
    load_config(config_path)

    if args.port:
        CONFIG["port"] = args.port
    if args.cookie_file:
        CONFIG["cookie_file"] = args.cookie_file
    if args.proxy:
        CONFIG["proxy"] = args.proxy
    if args.debug:
        CONFIG["debug_mode"] = True

    # Initialize HTTP client
    get_http_client()
    update_gemini_bl()

    class ThreadedServer(ThreadingMixIn, HTTPServer):
        daemon_threads = True
        allow_reuse_address = True

    port = CONFIG["port"]
    server = ThreadedServer((CONFIG["host"], port), GeminiHandler)
    print(f"gemini-web2api v{__version__}")
    print(f"  Listening: http://0.0.0.0:{port}")
    print(f"  Base URL:  http://localhost:{port}/v1")
    print(f"  Transport: {'curl_cffi (Chrome TLS fingerprint)' if HAS_CURL_CFFI else 'urllib (no fingerprint - install curl_cffi for stealth)'}")
    print(f"  Models:    {', '.join(EXPOSED_MODELS.keys())}")
    print(f"  Aliases:   {len(MODEL_ALIASES)} legacy names supported")
    print(f"  API Key:   {'configured (set via API_KEY env)' if CONFIG.get('api_key') else 'none (open access)'}")
    print(f"  Cookie:    {'yes (' + CONFIG['cookie_file'] + ')' if CONFIG.get('cookie_file') else 'none (anonymous)'}")
    print(f"  Proxy:     {CONFIG.get('proxy') or 'none (uses system env HTTP_PROXY/HTTPS_PROXY)'}")
    print(f"  Retry:     {CONFIG['retry_attempts']}x / {CONFIG['retry_delay_sec']}s")
    print(f"  Jitter:    {CONFIG['jitter_min_ms']}-{CONFIG['jitter_max_ms']}ms")
    print(f"  Debug:     {'enabled' if CONFIG.get('debug_mode') else 'disabled'}")
    print()
    try:
        server.serve_forever()
    except KeyboardInterrupt:
        print("\nStopped.")
        get_http_client().close()
        server.server_close()


if __name__ == "__main__":
    main()