"""AI 模型配置：每个组织可在页面配置 OpenAI 或本地 OpenAI 兼容服务（Ollama / LM Studio / vLLM 等）。

数据库配置优先；未配置时回退到环境变量（AI_ENABLED / OPENAI_*），保持旧行为兼容。
API Key 只存后端，读取接口只做脱敏回显，绝不把密钥下发到浏览器。
"""

import httpx
from django.conf import settings
from django.http import JsonResponse

from .models import AIConfig
from .views import APIError, audit, body, endpoint

PROVIDERS = ("openai", "local")
OPENAI_BASE_URL = "https://api.openai.com/v1"


def require_full_admin(request):
    if request.member.departments:
        raise APIError("没有配置 AI 模型的权限", 403)


def resolve(org):
    """返回生效的 AI 配置字典；未启用或配置不完整时返回 None。"""
    cfg = AIConfig.objects.filter(organization=org).first()
    if cfg:
        base_url = (cfg.base_url or "").rstrip("/") or (OPENAI_BASE_URL if cfg.provider == "openai" else "")
        key_required = cfg.provider == "openai"
        if not cfg.enabled or not base_url or not cfg.model or (key_required and not cfg.api_key):
            return None
        return {
            "enabled": True,
            "provider": cfg.provider,
            "base_url": base_url,
            "api_key": cfg.api_key,
            "model": cfg.model,
        }
    if settings.AI_ENABLED and settings.OPENAI_API_KEY and settings.OPENAI_MODEL:
        return {
            "enabled": True,
            "provider": "openai",
            "base_url": (settings.OPENAI_BASE_URL or OPENAI_BASE_URL).rstrip("/"),
            "api_key": settings.OPENAI_API_KEY,
            "model": settings.OPENAI_MODEL,
        }
    return None


def org_models_endpoint(org):
    """组织配置或环境回退的 base_url/api_key，用于探测模型列表。"""
    cfg = AIConfig.objects.filter(organization=org).first()
    if cfg:
        base_url = (cfg.base_url or "").rstrip("/") or (OPENAI_BASE_URL if cfg.provider == "openai" else "")
        return base_url, cfg.api_key
    return (settings.OPENAI_BASE_URL or OPENAI_BASE_URL).rstrip("/"), settings.OPENAI_API_KEY


@endpoint(("GET", "PUT"), roles=("admin",))
def ai_config(request):
    require_full_admin(request)
    org = request.member.organization
    if request.method == "GET":
        cfg = AIConfig.objects.filter(organization=org).first()
        return JsonResponse(
            {
                "enabled": cfg.enabled if cfg else False,
                "provider": cfg.provider if cfg else "local",
                "base_url": cfg.base_url if cfg else "",
                "model": cfg.model if cfg else "",
                "api_key_set": bool(cfg and cfg.api_key),
                "updated_at": cfg.updated_at.isoformat() if cfg else None,
            }
        )
    data = body(request)
    enabled = data.get("enabled")
    provider = data.get("provider")
    base_url = data.get("base_url", "")
    api_key = data.get("api_key", "")
    model = data.get("model", "")
    if type(enabled) is not bool or provider not in PROVIDERS:
        raise APIError("AI 配置参数无效")
    if not isinstance(base_url, str) or len(base_url) > 500:
        raise APIError("Base URL 无效")
    base_url = base_url.rstrip("/")
    if base_url and not base_url.startswith(("http://", "https://")):
        raise APIError("Base URL 必须以 http:// 或 https:// 开头")
    if not isinstance(api_key, str) or len(api_key) > 500:
        raise APIError("API Key 无效")
    if not isinstance(model, str) or len(model) > 200:
        raise APIError("模型名无效")
    cfg = AIConfig.objects.filter(organization=org).first()
    if enabled:
        if provider == "local" and not base_url:
            raise APIError("本地服务需要填写 Base URL，例如 http://127.0.0.1:11434/v1")
        if provider == "openai" and not (api_key or (cfg and cfg.api_key)):
            raise APIError("OpenAI 服务需要 API Key")
        if not model:
            raise APIError("启用前需要填写模型名，可点击“获取可用模型”选择")
    key_changed = bool(api_key)
    defaults = {
        "enabled": enabled,
        "provider": provider,
        "base_url": base_url,
        "model": model,
    }
    if api_key:
        defaults["api_key"] = api_key
    if not cfg:
        AIConfig.objects.create(organization=org, **defaults)
    else:
        for field, value in defaults.items():
            setattr(cfg, field, value)
        cfg.save()
    audit(
        request,
        "ai_config.update",
        details={
            "provider": provider,
            "model": model,
            "enabled": enabled,
            "key_changed": key_changed,
        },
    )
    return JsonResponse({"ok": True})


@endpoint(roles=("admin",))
def ai_models(request):
    require_full_admin(request)
    base_url, api_key = org_models_endpoint(request.member.organization)
    if not base_url:
        raise APIError("请先保存 Base URL 再获取模型列表", 400)
    headers = {"Authorization": f"Bearer {api_key}"} if api_key else {}
    try:
        with httpx.Client(timeout=10) as client:
            response = client.get(f"{base_url}/models", headers=headers)
            response.raise_for_status()
            data = response.json()
        items = data.get("data", [])
        ids = [m.get("id") for m in items if isinstance(m, dict) and isinstance(m.get("id"), str)]
        if not ids and isinstance(data.get("models"), list):
            ids = [
                m.get("name")
                for m in data["models"]
                if isinstance(m, dict) and isinstance(m.get("name"), str)
            ]
        return JsonResponse({"items": ids[:200]})
    except (httpx.HTTPError, ValueError, AttributeError) as exc:
        raise APIError("无法从该服务获取模型列表，请检查 Base URL 与 API Key", 502) from exc