function assertRouter(api) {
  if (!api || typeof api.get !== 'function' || typeof api.post !== 'function') {
    throw new Error('attachPortalTemplateCatalogRoutes requires an Express-compatible router');
  }
}

export function attachPortalTemplateCatalogRoutes(
  api,
  {
    getTemplateCatalog = () => null,
    ensureMindSpaceEnabled = () => false,
    sendData = (res, _req, data) => res.json({ data }),
    sendError = (res, _req, status, code, message) =>
      res.status(status).json({ error: { code, message } }),
  } = {},
) {
  assertRouter(api);

  api.get('/mindspace/v1/template-catalog', async (req, res) => {
    const catalog = getTemplateCatalog();
    if (!catalog || !ensureMindSpaceEnabled(res, req)) return;
    try {
      const items = await catalog.listCatalogForUser(req.currentUser.id);
      return sendData(res, req, { items });
    } catch (error) {
      const message = error instanceof Error ? error.message : '读取模板商城失败';
      return sendError(res, req, 500, 'template_catalog_error', message);
    }
  });

  api.get('/mindspace/v1/template-catalog/mine', async (req, res) => {
    const catalog = getTemplateCatalog();
    if (!catalog || !ensureMindSpaceEnabled(res, req)) return;
    try {
      const items = await catalog.listMine(req.currentUser.id);
      return sendData(res, req, { items });
    } catch (error) {
      const message = error instanceof Error ? error.message : '读取已购模板失败';
      return sendError(res, req, 500, 'template_catalog_error', message);
    }
  });

  api.post('/mindspace/v1/template-catalog/:skillName/purchase', async (req, res) => {
    const catalog = getTemplateCatalog();
    if (!catalog || !ensureMindSpaceEnabled(res, req)) return;
    try {
      const result = await catalog.purchaseWithBalance(req.currentUser.id, req.params.skillName);
      if (!result.ok) {
        if (result.code === 'INSUFFICIENT_BALANCE') {
          return res.status(402).json({
            error: {
              code: result.code,
              message: result.message,
            },
            details: {
              balanceCents: result.balanceCents,
              minRechargeCents: result.minRechargeCents,
              suggestedTiers: result.suggestedTiers,
            },
          });
        }
        return sendError(res, req, 400, 'template_purchase_failed', result.message);
      }
      return sendData(res, req, result);
    } catch (error) {
      const message = error instanceof Error ? error.message : '购买模板失败';
      return sendError(res, req, 500, 'template_purchase_error', message);
    }
  });

  api.post('/mindspace/v1/template-catalog/:skillName/favorite', async (req, res) => {
    const catalog = getTemplateCatalog();
    if (!catalog || !ensureMindSpaceEnabled(res, req)) return;
    try {
      const result = await catalog.toggleTemplateFavorite(req.currentUser.id, req.params.skillName);
      if (!result.ok) {
        return sendError(res, req, 400, 'template_favorite_failed', result.message);
      }
      return sendData(res, req, result);
    } catch (error) {
      const message = error instanceof Error ? error.message : '收藏操作失败';
      return sendError(res, req, 500, 'template_favorite_error', message);
    }
  });

  api.get('/mindspace/v1/template-catalog/:skillName/preview', async (req, res) => {
    const catalog = getTemplateCatalog();
    if (!catalog || !ensureMindSpaceEnabled(res, req)) return;
    try {
      const result = await catalog.getTemplatePreviewHtml(req.params.skillName);
      if (!result.ok) {
        return sendError(res, req, 404, 'template_preview_not_found', result.message);
      }
      res.setHeader('Content-Type', 'text/html; charset=utf-8');
      res.setHeader('Cache-Control', 'public, max-age=300');
      return res.send(result.html);
    } catch (error) {
      const message = error instanceof Error ? error.message : '读取模板预览失败';
      return sendError(res, req, 500, 'template_preview_error', message);
    }
  });

  api.post('/mindspace/v1/template-catalog/:skillName/checkout', async (req, res) => {
    const catalog = getTemplateCatalog();
    if (!catalog || !ensureMindSpaceEnabled(res, req)) return;
    try {
      const payScene = ['native', 'h5', 'jsapi'].includes(req.body?.payScene)
        ? req.body.payScene
        : 'native';
      const result = await catalog.createWechatCheckout({
        userId: req.currentUser.id,
        skillName: req.params.skillName,
        payScene,
        clientIp: req.ip,
      });
      if (!result.ok) {
        return sendError(res, req, 400, 'template_checkout_failed', result.message);
      }
      return sendData(res, req, result);
    } catch (error) {
      const message = error instanceof Error ? error.message : '创建模板支付订单失败';
      return sendError(res, req, 500, 'template_checkout_error', message);
    }
  });
}