/**
 * @license
 * Copyright Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
// [START sheets_quickstart]
const fs = require('fs');
const readline = require('readline');
const {google} = require('googleapis');

// If modifying these scopes, delete token.json.
const SCOPES = ['https://www.googleapis.com/auth/spreadsheets.readonly'];
// The file token.json stores the user's access and refresh tokens, and is
// created automatically when the authorization flow completes for the first
// time.
const TOKEN_PATH = 'token.json';

// Load client secrets from a local file.
fs.readFile('credentials.json', (err, content) => {
  if (err) return console.log('Error loading client secret file:', err);
  // Authorize a client with credentials, then call the Google Sheets API.
  authorize(JSON.parse(content), listMajors);
});

/**
 * Create an OAuth2 client with the given credentials, and then execute the
 * given callback function.
 * @param {Object} credentials The authorization client credentials.
 * @param {function} callback The callback to call with the authorized client.
 */
function authorize(credentials, callback) {
  const {client_secret, client_id, redirect_uris} = credentials.installed;
  const oAuth2Client = new google.auth.OAuth2(
      client_id, client_secret, redirect_uris[0]);

  // Check if we have previously stored a token.
  fs.readFile(TOKEN_PATH, (err, token) => {
    if (err) return getNewToken(oAuth2Client, callback);
    oAuth2Client.setCredentials(JSON.parse(token));
    callback(oAuth2Client);
  });
}

/**
 * Get and store new token after prompting for user authorization, and then
 * execute the given callback with the authorized OAuth2 client.
 * @param {google.auth.OAuth2} oAuth2Client The OAuth2 client to get token for.
 * @param {getEventsCallback} callback The callback for the authorized client.
 */
function getNewToken(oAuth2Client, callback) {
  const authUrl = oAuth2Client.generateAuthUrl({
    access_type: 'offline',
    scope: SCOPES,
  });
  console.log('Authorize this app by visiting this url:', authUrl);
  const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
  });
  rl.question('Enter the code from that page here: ', (code) => {
    rl.close();
    oAuth2Client.getToken(code, (err, token) => {
      if (err) return console.error('Error while trying to retrieve access token', err);
      oAuth2Client.setCredentials(token);
      // Store the token to disk for later program executions
      fs.writeFile(TOKEN_PATH, JSON.stringify(token), (err) => {
        if (err) return console.error(err);
        console.log('Token stored to', TOKEN_PATH);
      });
      callback(oAuth2Client);
    });
  });
}

/**
 * Prints the names and majors of students in a sample spreadsheet:
 * @see https://docs.google.com/spreadsheets/d/1BxiMVs0XRA5nFMdKvBdBZjgmUUqptlbs74OgvE2upms/edit
 * @param {google.auth.OAuth2} auth The authenticated Google OAuth client.
 */
function listMajors(auth) {
  const sheets = google.sheets({version: 'v4', auth});
  sheets.spreadsheets.values.get({
    spreadsheetId: '1GWnrP4WepYM8ERqSVGwKw5yxezMLnpdjxT0usn5mQKU',
    range: 'i18n',
  }, (err, res) => {
    if (err) return console.log('The API returned an error: ' + err);
    const rows = res.data.values;

    // console.info(rows)
    let keyIndex=rows[0].indexOf('key')
    if (rows.length&&keyIndex!==-1&&rows[0][keyIndex+1]==='default') {

      let keys=rows.slice(1).map((item,row)=>{return {row:row+1,key:item[keyIndex]}})

      let i18n= rows[0].slice(keyIndex+1).map(()=>{return {}})
      console.info(`共找到${i18n.length-1}种语言,${keys.length}个词条`)
      keys.map((key,row)=>{
        i18n.map((obj,column)=>{

          if(!/^[a-zA-Z][0-9a-zA-Z_]+$/g.test(key.key)){
            console.error(`第${row+1}行${key.key}不合法，key必须以英文字母开头，只能包含字母数字和下划线`)
            return
          }

          if(key.key in obj){
            console.warn(`第${row+1}行${key.key}已经在第${rows[key.row]}行定义了！`)
          }
          let value=rows[row+1][column+keyIndex+1]||''
          if(value===''){
            console.warn(`第${row+1}行${key.key}对应的${rows[0].slice(keyIndex+1)[column]}没有翻译！`)
          }
          obj[key.key]=value
        })
      })

      console.info(i18n)
      let dir='locale'
      if (!fs.existsSync(dir)){
        fs.mkdir(dir,function(error){
          if(error){
            console.log(error);
            return false;
          }
          createFile(rows[0].slice(keyIndex+1),i18n)
        })
      }else{
        createFile(rows[0].slice(keyIndex+1),i18n)
      }


    } else {
      console.log('语言包没有翻译文本或格式不合法');
    }
  });
}

function createFile(languages,i18n){
  languages.map((filename,index)=>{
    fs.writeFile(`locale/${filename}.json`, JSON.stringify(i18n[index]), (err) => {
      if (err) {
        throw err;
      }
    });
  })
}
// [END sheets_quickstart]

module.exports = {
  SCOPES,
  listMajors,
};