import { z } from "zod";
import { requireAdmin } from "@/lib/middleware/admin";
import {
  getAllSystemSettings,
  getSystemSetting,
  upsertSystemSetting,
} from "@/lib/db/queries";
import { ChatSDKError } from "@/lib/errors";
import { probeBflModelSupport } from "@/lib/realtime/bfl-capability";

const settingSchema = z.object({
  key: z.string(),
  value: z.any(),
});

const DEFAULT_BFL_MODEL = "flux-2-klein-4b";
const DEFAULT_BFL_BASE_URL = "https://api.bfl.ai";

function isObjectLike(value: unknown): value is Record<string, unknown> {
  return Boolean(value) && typeof value === "object" && !Array.isArray(value);
}

function mapProbeStatus(code: string) {
  if (code === "UPSTREAM_ERROR") return 502;
  return 400;
}

export async function GET(request: Request) {
  try {
    await requireAdmin();

    const { searchParams } = new URL(request.url);
    const key = searchParams.get("key");

    if (key) {
      const setting = await getSystemSetting({ key });
      return Response.json({ setting });
    }

    const settings = await getAllSystemSettings();
    return Response.json({ settings });
  } catch (error) {
    if (error instanceof ChatSDKError) {
      return error.toResponse();
    }
    return new ChatSDKError("offline:admin").toResponse();
  }
}

export async function POST(request: Request) {
  try {
    const session = await requireAdmin();

    const body = await request.json();
    const { key, value } = settingSchema.parse(body);

    let nextValue = value;

    if (key === "realtime_canvas_config") {
      if (!isObjectLike(value)) {
        return new ChatSDKError("bad_request:api", "realtime_canvas_config value 必须为对象").toResponse();
      }

      const enabled = value.enabled !== false;
      const bflApiKey = String(
        value.bflApiKey || value.runwareApiKey || value.falApiKey || value.apiKey || ""
      ).trim();
      const bflModel = String(value.bflModel || value.runwareModel || DEFAULT_BFL_MODEL).trim() || DEFAULT_BFL_MODEL;
      const bflBaseUrl = String(value.bflBaseUrl || DEFAULT_BFL_BASE_URL).trim() || DEFAULT_BFL_BASE_URL;
      const renderMode =
        value.renderMode === "strict-structure" ||
        value.renderMode === "stylize" ||
        value.renderMode === "balanced"
          ? value.renderMode
          : "balanced";

      if (enabled) {
        if (!bflApiKey) {
          return new ChatSDKError("bad_request:api", "启用实时画布必须配置 BFL API Key").toResponse();
        }
        const probeResult = await probeBflModelSupport({
          apiKey: bflApiKey,
          modelId: bflModel,
          baseUrl: bflBaseUrl,
        });
        if (!probeResult.supported) {
          return Response.json(
            {
              code: probeResult.code,
              message: probeResult.message,
            },
            { status: mapProbeStatus(probeResult.code) }
          );
        }
      }

      nextValue = {
        ...value,
        bflApiKey,
        bflModel,
        bflBaseUrl,
        runwareApiKey: bflApiKey,
        falApiKey: bflApiKey,
        apiKey: bflApiKey,
        runwareModel: bflModel,
        renderMode,
      };
    }

    const setting = await upsertSystemSetting({
      key,
      value: nextValue,
      updatedBy: session.user.id,
    });

    return Response.json({ setting: setting[0] });
  } catch (error) {
    if (error instanceof ChatSDKError) {
      return error.toResponse();
    }
    if (error instanceof z.ZodError) {
      return new ChatSDKError("bad_request:api", error.message).toResponse();
    }
    return new ChatSDKError("offline:admin").toResponse();
  }
}