const dynamoClient = require('./dynamoClient');

const create = async (tableName, item) => {
  const fullItem = {...item, created_at: Date.now()};

  await dynamoClient.put({
    TableName: tableName,
    Item: fullItem
  }).promise();

  // put does not return saved item, just return our object
  return fullItem;
};

const get = async (tableName, keyMap) => {
  const res = await dynamoClient.get({
    TableName: tableName,
    Key: keyMap
  }).promise();

  return res && res.Item;
};

const scan = async (tableName) => {
  const res = await dynamoClient.scan({
    TableName: tableName
  }).promise();

  return res && res.Items;
};

const queryByID = async (tableName, idKeyName, id) => {
  // querying by id can be used when we are querying a table
  // that has a sortKey, but we don't need to use the sortKey
  const res = await dynamoClient.query({
    TableName: tableName,
    KeyConditionExpression: "#id = :idValue",
    ExpressionAttributeNames: {
      "#id": idKeyName,
    },
    ExpressionAttributeValues: {
      ":idValue": id,
    }
  }).promise();

  return res && res.Items;
};

const update = async (tableName, keyMap, ue, eav) => {
  const res = await dynamoClient.update({
    TableName: tableName,
    Key: keyMap,
    UpdateExpression: ue,
    ExpressionAttributeValues: eav,
    ReturnValues: 'UPDATED_NEW'
  }).promise();

  console.log('update res', res);

  return res;
};

module.exports = {
  client: dynamoClient,
  create,
  get,
  scan,
  queryByID,
  update
};