const fs = require('fs-extra');
const path = require('path');

const CONFIG_DIR = path.join(process.cwd(), 'data');
const CONFIG_PATH = path.join(CONFIG_DIR, 'location-config.json');

const DEFAULT_LOCATION = {
   longitude: 0,
   latitude: 0,
};

const readRawBody = (req) =>
   new Promise((resolve, reject) => {
      let raw = '';
      req.setEncoding('utf8');
      req.on('data', (chunk) => {
         raw += chunk;
      });
      req.on('end', () => resolve(raw));
      req.on('error', reject);
   });

const parseRequestBody = async (ctx) => {
   if (ctx.request?.body && Object.keys(ctx.request.body).length > 0) {
      return ctx.request.body;
   }

   const raw = await readRawBody(ctx.req);
   if (!raw) {
      return {};
   }

   try {
      return JSON.parse(raw);
   } catch (error) {
      console.error('解析经纬度配置请求体失败:', error);
      return {};
   }
};

const normalizeNumber = (value) => {
   const num = Number(value);
   return Number.isFinite(num) ? num : 0;
};

const ensureConfigDir = async () => {
   await fs.ensureDir(CONFIG_DIR);
};

const readLocationConfig = async () => {
   try {
      await ensureConfigDir();
      const exists = await fs.pathExists(CONFIG_PATH);
      if (!exists) {
         return DEFAULT_LOCATION;
      }

      const content = await fs.readJson(CONFIG_PATH);
      return {
         longitude: normalizeNumber(content?.longitude),
         latitude: normalizeNumber(content?.latitude),
      };
   } catch (error) {
      console.error('读取经纬度配置失败:', error);
      return DEFAULT_LOCATION;
   }
};

module.exports.getLocationConfig = async (ctx) => {
   ctx.status = 200;
   ctx.body = await readLocationConfig();
};

module.exports.saveLocationConfig = async (ctx) => {
   try {
      const requestBody = await parseRequestBody(ctx);
      const longitude = normalizeNumber(requestBody?.longitude);
      const latitude = normalizeNumber(requestBody?.latitude);

      await ensureConfigDir();
      const data = { longitude, latitude };
      await fs.writeJson(CONFIG_PATH, data, { spaces: 2 });
      ctx.status = 200;
      ctx.body = {
         success: true,
         ...data,
      };
   } catch (error) {
      console.error('保存经纬度配置失败:', error);
      ctx.status = 500;
      ctx.body = {
         success: false,
         message: 'save location config failed',
      };
   }
};