const logger = require('winston');
const db = require('../../../../models');

const authenticateChannelCredentials = (channelName, channelId, userPassword) => {
  return new Promise((resolve, reject) => {
    // hoisted variables
    let channelData;
    // build the params for finding the channel
    let channelFindParams = {};
    if (channelName) channelFindParams['channelName'] = channelName;
    if (channelId) channelFindParams['channelClaimId'] = channelId;
    // find the channel
    db.Channel
      .findOne({
        where: channelFindParams,
      })
      .then(channel => {
        if (!channel) {
          logger.debug('no channel found');
          throw new Error('Authentication failed, you do not have access to that channel');
        }
        channelData = channel.get();
        logger.debug('channel data:', channelData);
        return db.User.findOne({
          where: { userName: channelData.channelName.substring(1) },
        });
      })
      .then(user => {
        if (!user) {
          logger.debug('no user found');
          throw new Error('Authentication failed, you do not have access to that channel');
        }
        return user.comparePassword(userPassword);
      })
      .then(isMatch => {
        if (!isMatch) {
          logger.debug('incorrect password');
          throw new Error('Authentication failed, you do not have access to that channel');
        }
        logger.debug('...password was a match...');
        resolve(channelData);
      })
      .catch(error => {
        reject(error);
      });
  });
};

const authenticateUser = (channelName, channelId, channelPassword, user) => {
  return new Promise((resolve, reject) => {
    // case: no channelName or channel Id are provided (anonymous), regardless of whether user token is provided
    if (!channelName && !channelId) {
      resolve({
        channelName   : null,
        channelClaimId: null,
      });
      return;
    }
    // case: channelName or channel Id are provided with user token
    if (user) {
      if (channelName && channelName !== user.channelName) {
        reject(new Error('the provided channel name does not match user credentials'));
        return;
      }
      if (channelId && channelId !== user.channelClaimId) {
        reject(new Error('the provided channel id does not match user credentials'));
        return;
      }
      resolve({
        channelName   : user.channelName,
        channelClaimId: user.channelClaimId,
      });
      return;
    }
    // case: channelName or channel Id are provided with password instead of user token
    if (!channelPassword) {
      reject(new Error('no channel password provided'));
      return;
    }
    resolve(authenticateChannelCredentials(channelName, channelId, channelPassword));
  });
};

module.exports = authenticateUser;