import { z } from "zod";
import { requireAdmin } from "@/lib/middleware/admin";
import {
  createAiModel,
  createAiProvider,
  getAiModelById,
  getAiProviderById,
  getAllAiModels,
  getAllSystemSettings,
  getSystemSetting,
  upsertSystemSetting,
  updateAiModel,
  updateAiProvider,
} from "@/lib/db/queries";
import { ChatSDKError } from "@/lib/errors";
import { probeBflModelSupport } from "@/lib/realtime/bfl-capability";
import { probeReplicateModelSupport } from "@/lib/realtime/replicate-capability";
import {
  normalizeRealtimeCanvasConfigForStorage,
  resolveRealtimeProviders,
} from "@/lib/realtime/config";
import { db } from "@/lib/db";
import { siteSettings } from "@/lib/db/schema";
import { eq } from "drizzle-orm";

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

const moonshotDetailAgentConfigSchema = z.object({
  providerId: z.string().uuid().optional(),
  modelEntryId: z.string().uuid().optional(),
  providerName: z.string().trim().min(1).max(128).optional(),
  baseUrl: z.string().trim().min(1),
  apiKey: z.string().optional(),
  modelId: z.string().trim().min(1).max(128).optional(),
  displayName: z.string().trim().min(1).max(128).optional(),
  isEnabled: z.boolean().optional(),
});

const MOONSHOT_OFFICIAL_BASE_URL = "https://api.moonshot.cn/v1";
const MOONSHOT_KIMI_K25_MODEL_ID = "kimi-k2.5";

function isMoonshotOfficialBaseUrl(value: string) {
  return String(value || "").trim().replace(/\/+$/, "") === MOONSHOT_OFFICIAL_BASE_URL;
}

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 === "moonshot_detail_agent_config") {
      const config = moonshotDetailAgentConfigSchema.parse(value || {});
      const normalizedBaseUrl = String(config.baseUrl || "").trim() || MOONSHOT_OFFICIAL_BASE_URL;
      const normalizedModelId = String(config.modelId || "").trim() || MOONSHOT_KIMI_K25_MODEL_ID;
      const normalizedDisplayName = String(config.displayName || "").trim() || "官方 Kimi K2.5";
      const normalizedProviderName =
        String(config.providerName || "").trim() || "Moonshot AI (Official)";
      const normalizedApiKey = String(config.apiKey || "").trim();
      const enabled = config.isEnabled !== false;

      if (!isMoonshotOfficialBaseUrl(normalizedBaseUrl)) {
        return new ChatSDKError(
          "bad_request:api",
          `Moonshot 官方地址必须为 ${MOONSHOT_OFFICIAL_BASE_URL}`,
        ).toResponse();
      }

      if (!config.providerId && !normalizedApiKey) {
        return new ChatSDKError("bad_request:api", "缺少 Moonshot 官方 API Key").toResponse();
      }

      const [existingSiteSettings] = await db.select().from(siteSettings).limit(1);

      const providerRows = config.providerId
        ? await updateAiProvider({
            id: config.providerId,
            name: normalizedProviderName,
            type: "openai",
            baseUrl: normalizedBaseUrl,
            apiKey: normalizedApiKey || undefined,
            isEnabled: enabled,
            updatedBy: session.user.id,
          })
        : await createAiProvider({
            name: normalizedProviderName,
            type: "openai",
            baseUrl: normalizedBaseUrl,
            apiKey: normalizedApiKey,
            isEnabled: enabled,
            updatedBy: session.user.id,
          });

      const provider = providerRows[0];
      if (!provider) {
        return new ChatSDKError("bad_request:database", "保存 Moonshot 提供商失败").toResponse();
      }

      let existingModel =
        config.modelEntryId ? await getAiModelById({ id: config.modelEntryId }) : undefined;

      if (!existingModel) {
        const allModels = await getAllAiModels();
        existingModel =
          allModels.find(
            (model) => model.providerId === provider.id && model.modelId === normalizedModelId,
          ) || undefined;
      }

      const modelRows = existingModel
        ? await updateAiModel({
            id: existingModel.id,
            providerId: provider.id,
            modelId: normalizedModelId,
            displayName: normalizedDisplayName,
            description: "Moonshot 官方 Kimi K2.5，专用于 AI详情生成 的规划与排版复审",
            supportsVision: true,
            supportsImageGen: false,
            isEnabled: enabled,
            isHidden: false,
            isDefault: false,
            isAgentModel: false,
            isMultimodal: true,
          })
        : await createAiModel({
            providerId: provider.id,
            modelId: normalizedModelId,
            displayName: normalizedDisplayName,
            description: "Moonshot 官方 Kimi K2.5，专用于 AI详情生成 的规划与排版复审",
            supportsVision: true,
            supportsImageGen: false,
            isEnabled: enabled,
            isHidden: false,
            isDefault: false,
            isAgentModel: false,
            isMultimodal: true,
          });

      const model = modelRows[0];
      if (!model) {
        return new ChatSDKError("bad_request:database", "保存 Kimi K2.5 模型失败").toResponse();
      }

      if (existingSiteSettings) {
        await db
          .update(siteSettings)
          .set({
            canvasDetailAgentModelId: model.id,
            updatedAt: new Date(),
            updatedBy: session.user.id,
          })
          .where(eq(siteSettings.id, existingSiteSettings.id));
      } else {
        await db.insert(siteSettings).values({
          siteName: "AI Chatbot",
          canvasDetailAgentModelId: model.id,
          updatedBy: session.user.id,
        });
      }

      return Response.json({
        setting: {
          key: "moonshot_detail_agent_config",
          value: {
            providerId: provider.id,
            modelEntryId: model.id,
            providerName: provider.name,
            baseUrl: provider.baseUrl,
            modelId: model.modelId,
            displayName: model.displayName,
            isEnabled: model.isEnabled,
            canvasDetailAgentModelId: model.id,
          },
        },
      });
    }

    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 normalizedValue = normalizeRealtimeCanvasConfigForStorage(value);
      const providers = resolveRealtimeProviders(normalizedValue);

      if (enabled) {
        if (providers.length === 0) {
          return new ChatSDKError("bad_request:api", "启用实时画布必须至少配置一个可用服务").toResponse();
        }

        for (const provider of providers) {
          const probeResult =
            provider.type === "replicate"
              ? await probeReplicateModelSupport({
                  apiKey: provider.apiKey,
                  modelId: provider.model,
                  baseUrl: provider.baseUrl,
                })
              : await probeBflModelSupport({
                  apiKey: provider.apiKey,
                  modelId: provider.model,
                  baseUrl: provider.baseUrl,
                });

          if (!probeResult.supported) {
            return Response.json(
              {
                code: probeResult.code,
                message: `${provider.label}校验失败：${probeResult.message}`,
              },
              { status: mapProbeStatus(probeResult.code) }
            );
          }
        }
      }

      nextValue = normalizedValue;
    }

    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();
  }
}