import { Router } from "express";
const router = Router();
import kvStore from "../utils/kvStore.js";
import { kvTokenAuth } from "../middleware/kvTokenAuth.js";
import errors from "../utils/errors.js";

// 使用KV专用token认证
router.use(kvTokenAuth);

/**
 * GET /_keys
 * 获取当前token对应设备的键名列表（分页，不包括内容）
 */
router.get(
  "/_keys",
  errors.catchAsync(async (req, res) => {
    const deviceId = res.locals.deviceId;
    const { sortBy, sortDir, limit, skip } = req.query;

    // 构建选项
    const options = {
      sortBy: sortBy || "key",
      sortDir: sortDir || "asc",
      limit: limit ? parseInt(limit) : 100,
      skip: skip ? parseInt(skip) : 0,
    };

    const keys = await kvStore.listKeysOnly(deviceId, options);
    const totalRows = keys.length;

    // 构建响应对象
    const response = {
      keys: keys,
      total_rows: totalRows,
      current_page: {
        limit: options.limit,
        skip: options.skip,
        count: keys.length,
      },
    };

    // 如果还有更多数据，添加load_more字段
    const nextSkip = options.skip + options.limit;
    if (nextSkip < totalRows) {
      const baseUrl = `${req.baseUrl}/_keys`;
      const queryParams = new URLSearchParams({
        sortBy: options.sortBy,
        sortDir: options.sortDir,
        limit: options.limit,
        skip: nextSkip,
      }).toString();

      response.load_more = `${baseUrl}?${queryParams}`;
    }

    return res.json(response);
  })
);

/**
 * GET /
 * 获取当前token对应设备的所有键名及元数据列表
 */
router.get(
  "/",
  errors.catchAsync(async (req, res) => {
    const deviceId = res.locals.deviceId;
    const { sortBy, sortDir, limit, skip } = req.query;

    // 构建选项
    const options = {
      sortBy: sortBy || "key",
      sortDir: sortDir || "asc",
      limit: limit ? parseInt(limit) : 100,
      skip: skip ? parseInt(skip) : 0,
    };

    const keys = await kvStore.list(deviceId, options);
    const totalRows = await kvStore.count(deviceId);

    // 构建响应对象
    const response = {
      items: keys,
      total_rows: totalRows,
    };

    // 如果还有更多数据，添加load_more字段
    const nextSkip = options.skip + options.limit;
    if (nextSkip < totalRows) {
      const baseUrl = `${req.baseUrl}`;
      const queryParams = new URLSearchParams({
        sortBy: options.sortBy,
        sortDir: options.sortDir,
        limit: options.limit,
        skip: nextSkip,
      }).toString();

      response.load_more = `${baseUrl}?${queryParams}`;
    }

    return res.json(response);
  })
);

/**
 * GET /:key
 * 通过键名获取键值
 */
router.get(
  "/:key",
  errors.catchAsync(async (req, res, next) => {
    const deviceId = res.locals.deviceId;
    const { key } = req.params;

    const value = await kvStore.get(deviceId, key);

    if (value === null) {
      return next(
        errors.createError(404, `未找到键名为 '${key}' 的记录`)
      );
    }

    return res.json(value);
  })
);

/**
 * GET /:key/metadata
 * 获取键的元数据
 */
router.get(
  "/:key/metadata",
  errors.catchAsync(async (req, res, next) => {
    const deviceId = res.locals.deviceId;
    const { key } = req.params;

    const metadata = await kvStore.getMetadata(deviceId, key);
    if (!metadata) {
      return next(
        errors.createError(404, `未找到键名为 '${key}' 的记录`)
      );
    }
    return res.json(metadata);
  })
);

/**
 * POST /_batchimport
 * 批量导入键值对
 */
router.post(
  "/_batchimport",
  errors.catchAsync(async (req, res, next) => {
    const deviceId = res.locals.deviceId;
    const data = req.body;

    if (!data || Object.keys(data).length === 0) {
      return next(
        errors.createError(
          400,
          '请提供有效的JSON数据，格式为 {"key":{}, "key2":{}}'
        )
      );
    }

    // 获取客户端IP
    const creatorIp =
      req.headers["x-forwarded-for"] ||
      req.connection.remoteAddress ||
      req.socket.remoteAddress ||
      req.connection.socket?.remoteAddress ||
      "";

    const results = [];
    const errorList = [];

    // 批量处理所有键值对
    for (const [key, value] of Object.entries(data)) {
      try {
        const result = await kvStore.upsert(deviceId, key, value, creatorIp);
        results.push({
          key: result.key,
          created: result.createdAt.getTime() === result.updatedAt.getTime(),
        });
      } catch (error) {
        errorList.push({
          key,
          error: error.message,
        });
      }
    }

    return res.status(200).json({
      deviceId,
      total: Object.keys(data).length,
      successful: results.length,
      failed: errorList.length,
      results,
      errors: errorList.length > 0 ? errorList : undefined,
    });
  })
);

/**
 * POST /:key
 * 更新或创建键值
 */
router.post(
  "/:key",
  errors.catchAsync(async (req, res, next) => {
    const deviceId = res.locals.deviceId;
    const { key } = req.params;
    const value = req.body;

    if (!value || Object.keys(value).length === 0) {
      return next(errors.createError(400, "请提供有效的JSON值"));
    }

    // 获取客户端IP
    const creatorIp =
      req.headers["x-forwarded-for"] ||
      req.connection.remoteAddress ||
      req.socket.remoteAddress ||
      req.connection.socket?.remoteAddress ||
      "";

    const result = await kvStore.upsert(deviceId, key, value, creatorIp);
    return res.status(200).json({
      deviceId: result.deviceId,
      key: result.key,
      created: result.createdAt.getTime() === result.updatedAt.getTime(),
      updatedAt: result.updatedAt,
    });
  })
);

/**
 * DELETE /:key
 * 删除键值对
 */
router.delete(
  "/:key",
  errors.catchAsync(async (req, res, next) => {
    const deviceId = res.locals.deviceId;
    const { key } = req.params;

    const result = await kvStore.delete(deviceId, key);

    if (!result) {
      return next(
        errors.createError(404, `未找到键名为 '${key}' 的记录`)
      );
    }

    // 204状态码表示成功但无内容返回
    return res.status(204).end();
  })
);

export default router;