import { Router, type IRouter, type Request } from "express";
import { db } from "@workspace/db";
import { aiProvidersTable, type AiProvider } from "@workspace/db";
import { eq } from "drizzle-orm";
import {
  ListProvidersResponse,
  CreateProviderBody,
  UpdateProviderParams,
  UpdateProviderBody,
  UpdateProviderResponse,
  DeleteProviderParams,
  TestProviderParams,
  TestProviderResponse,
  TestProviderConnectionBody,
  ListProviderModelsBody,
  ListProviderModelsResponse,
} from "@workspace/api-zod";
import { callProvider, listProviderModels } from "../lib/aiAnalysis";
import { t, reqLang } from "../lib/i18n";

const router: IRouter = Router();

function maskToken(token: string | null): string {
  if (!token) return "";
  if (token.length <= 8) return "••••";
  return `${token.slice(0, 3)}…${token.slice(-4)}`;
}

function serializeProvider(p: AiProvider) {
  return {
    id: p.id,
    name: p.name,
    apiType: p.apiType,
    baseUrl: p.baseUrl,
    model: p.model,
    enabled: p.enabled,
    hasToken: !!p.apiToken,
    tokenPreview: maskToken(p.apiToken),
    createdAt: p.createdAt.toISOString(),
  };
}

router.get("/providers", async (_req, res) => {
  const rows = await db.select().from(aiProvidersTable).orderBy(aiProvidersTable.id);
  res.json(ListProvidersResponse.parse(rows.map(serializeProvider)));
});

router.post("/providers", async (req, res) => {
  const parsed = CreateProviderBody.safeParse(req.body);
  if (!parsed.success)
    return res
      .status(400)
      .json({ message: t("invalidInput", reqLang(req)), details: parsed.error.issues });
  const d = parsed.data;
  const [created] = await db
    .insert(aiProvidersTable)
    .values({
      name: d.name,
      apiType: d.apiType,
      baseUrl: d.baseUrl,
      model: d.model,
      apiToken: d.apiToken ?? null,
      enabled: d.enabled ?? true,
    })
    .returning();
  return res
    .status(201)
    .json(UpdateProviderResponse.parse(serializeProvider(created)));
});

router.patch("/providers/:id", async (req, res) => {
  const params = UpdateProviderParams.safeParse(req.params);
  if (!params.success) return res.status(400).json({ message: t("invalidId", reqLang(req)) });
  const parsed = UpdateProviderBody.safeParse(req.body);
  if (!parsed.success)
    return res
      .status(400)
      .json({ message: t("invalidInput", reqLang(req)), details: parsed.error.issues });
  const d = parsed.data;

  const update: Partial<typeof aiProvidersTable.$inferInsert> = {};
  if (d.name !== undefined) update.name = d.name;
  if (d.apiType !== undefined) update.apiType = d.apiType;
  if (d.baseUrl !== undefined) update.baseUrl = d.baseUrl;
  if (d.model !== undefined) update.model = d.model;
  if (d.enabled !== undefined) update.enabled = d.enabled;
  if (d.apiToken !== undefined && d.apiToken !== "")
    update.apiToken = d.apiToken;

  const [updated] = await db
    .update(aiProvidersTable)
    .set(update)
    .where(eq(aiProvidersTable.id, params.data.id))
    .returning();
  if (!updated)
    return res.status(404).json({ message: t("providerNotFound", reqLang(req)) });
  return res.json(UpdateProviderResponse.parse(serializeProvider(updated)));
});

router.delete("/providers/:id", async (req, res) => {
  const params = DeleteProviderParams.safeParse(req.params);
  if (!params.success) return res.status(400).json({ message: t("invalidId", reqLang(req)) });
  await db
    .delete(aiProvidersTable)
    .where(eq(aiProvidersTable.id, params.data.id));
  return res.status(204).send();
});

router.post("/providers/:id/test", async (req, res) => {
  const params = TestProviderParams.safeParse(req.params);
  if (!params.success) return res.status(400).json({ message: t("invalidId", reqLang(req)) });
  const [provider] = await db
    .select()
    .from(aiProvidersTable)
    .where(eq(aiProvidersTable.id, params.data.id));
  if (!provider)
    return res.status(404).json({ message: t("providerNotFound", reqLang(req)) });
  if (!provider.apiToken) {
    return res.json(
      TestProviderResponse.parse({
        ok: false,
        message: t("noApiTokenPlain", reqLang(req)),
      }),
    );
  }
  try {
    const reply = await callProvider(
      provider,
      "Du bist ein Verbindungstest.",
      'Antworte mit dem einzelnen Wort "OK".',
    );
    return res.json(
      TestProviderResponse.parse({
        ok: true,
        message: t("connSuccessReply", reqLang(req), {
          reply: reply.trim().slice(0, 80) || t("connReplyEmpty", reqLang(req)),
        }),
      }),
    );
  } catch (err) {
    return res.json(
      TestProviderResponse.parse({
        ok: false,
        message: err instanceof Error ? err.message : t("connFailed", reqLang(req)),
      }),
    );
  }
});

router.post("/providers/test-connection", async (req, res) => {
  const parsed = TestProviderConnectionBody.safeParse(req.body);
  if (!parsed.success)
    return res
      .status(400)
      .json({ message: t("invalidInput", reqLang(req)), details: parsed.error.issues });
  const d = parsed.data;

  let token: string | null =
    d.apiToken && d.apiToken !== "" ? d.apiToken : null;
  if (!token && d.providerId !== undefined && d.providerId !== null) {
    const [existing] = await db
      .select()
      .from(aiProvidersTable)
      .where(eq(aiProvidersTable.id, d.providerId));
    if (existing?.apiToken) token = existing.apiToken;
  }
  if (!token) {
    return res.json(
      TestProviderResponse.parse({
        ok: false,
        message: t("noApiTokenProvided", reqLang(req)),
      }),
    );
  }

  const hasModel = typeof d.model === "string" && d.model.trim() !== "";

  const provider: AiProvider = {
    id: d.providerId ?? 0,
    name: "",
    apiType: d.apiType,
    baseUrl: d.baseUrl,
    model: hasModel ? (d.model as string) : "",
    apiToken: token,
    enabled: true,
    createdAt: new Date(),
  };

  try {
    if (hasModel) {
      const reply = await callProvider(
        provider,
        "Du bist ein Verbindungstest.",
        'Antworte mit dem einzelnen Wort "OK".',
      );
      return res.json(
        TestProviderResponse.parse({
          ok: true,
          message: t("connSuccessReply", reqLang(req), {
            reply: reply.trim().slice(0, 80) || t("connReplyEmpty", reqLang(req)),
          }),
        }),
      );
    }
    const models = await listProviderModels(provider);
    return res.json(
      TestProviderResponse.parse({
        ok: true,
        message:
          models.length > 0
            ? t("connSuccessModels", reqLang(req), { count: String(models.length) })
            : t("connSuccessNoModels", reqLang(req)),
      }),
    );
  } catch (err) {
    return res.json(
      TestProviderResponse.parse({
        ok: false,
        message: err instanceof Error ? err.message : t("connFailed", reqLang(req)),
      }),
    );
  }
});

router.post("/providers/list-models", async (req, res) => {
  const parsed = ListProviderModelsBody.safeParse(req.body);
  if (!parsed.success)
    return res
      .status(400)
      .json({ message: t("invalidInput", reqLang(req)), details: parsed.error.issues });
  const d = parsed.data;

  let token: string | null =
    d.apiToken && d.apiToken !== "" ? d.apiToken : null;
  if (!token && d.providerId !== undefined && d.providerId !== null) {
    const [existing] = await db
      .select()
      .from(aiProvidersTable)
      .where(eq(aiProvidersTable.id, d.providerId));
    if (existing?.apiToken) token = existing.apiToken;
  }
  if (!token) {
    return res.json(
      ListProviderModelsResponse.parse({
        ok: false,
        models: [],
        message: t("noApiTokenProvided", reqLang(req)),
      }),
    );
  }

  const provider: AiProvider = {
    id: d.providerId ?? 0,
    name: "",
    apiType: d.apiType,
    baseUrl: d.baseUrl,
    model: "",
    apiToken: token,
    enabled: true,
    createdAt: new Date(),
  };

  try {
    const models = await listProviderModels(provider);
    return res.json(
      ListProviderModelsResponse.parse({ ok: true, models }),
    );
  } catch (err) {
    return res.json(
      ListProviderModelsResponse.parse({
        ok: false,
        models: [],
        message:
          err instanceof Error
            ? err.message
            : t("modelsLoadFailed", reqLang(req)),
      }),
    );
  }
});

export default router;