import { addCallback, runCallbacksAsync } from 'meteor/nova:core';
import Users from 'meteor/nova:users';
import Posts from 'meteor/nova:posts';
import Comments from 'meteor/nova:comments';
import { operateOnItem, getVotePower } from './vote.js';
import { updateScore } from './scoring.js';

/*

### posts.new.sync

- PostsNewUpvoteOwnPost

### comments.new.sync

- CommentsNewUpvoteOwnComment

### upvote.async
### downvote.async
### cancelUpvote.async
### cancelDownvote.async

- updateItemScore
- updateUser
- updateKarma

### posts.new.async
### comments.new.async

- UpvoteAsyncCallbacksAfterDocumentInsert

*/


// -------------------------- posts.new.sync ------------------------------- //

/**
 * @summary Make users upvote their own new posts (simulation)
 */
function PostsNewUpvoteOwnPost(post) {
  var postAuthor = Users.findOne(post.userId);
  return {...post, ...operateOnItem(Posts, post, postAuthor, 'upvote', false, 'insert')};
}

addCallback("posts.new.sync", PostsNewUpvoteOwnPost);


// ----------------------- comments.new.sync ------------------------------- //

/**
 * @summary Make users upvote their own new comments (simulation)
 */
function CommentsNewUpvoteOwnComment(comment) {
  var commentAuthor = Users.findOne(comment.userId);
  return {...comment, ...operateOnItem(Comments, comment, commentAuthor, 'upvote', false, 'insert')};
}

addCallback("comments.new.sync", CommentsNewUpvoteOwnComment);


// ----------------------------- vote.async ------------------------------- //

/**
 * @summary Update an item's (post or comment) score
 * @param {object} item - The item being operated on
 * @param {object} user - The user doing the operation
 * @param {object} collection - The collection the item belongs to
 * @param {string} operation - The operation being performed
 */
function updateItemScore(item, user, collection, operation, context) {
  updateScore({collection: collection, item: item, forceUpdate: true});
}

addCallback("upvote.async", updateItemScore);
addCallback("downvote.async", updateItemScore);
addCallback("cancelUpvote.async", updateItemScore);
addCallback("cancelDownvote.async", updateItemScore);


/**
 * @summary Update the profile of the user doing the operation
 * @param {object} item - The item being operated on
 * @param {object} user - The user doing the operation
 * @param {object} collection - The collection the item belongs to
 * @param {string} operation - The operation being performed
 */
function updateUser(item, user, collection, operation, context) {
  
  // uncomment for debug
  // console.log(item);
  // console.log(user);
  // console.log(collection._name);
  // console.log(operation);

  const update = {};
  const votePower = getVotePower(user);
  const vote = {
    itemId: item._id,
    votedAt: new Date(),
    power: votePower
  };

  switch (operation) {
    case "upvote":
      update.$addToSet = {'upvotedPosts': vote};
      break;
    case "downvote":
      update.$addToSet = {'downvotedPosts': vote};
      break;
    case "cancelUpvote":
      update.$pull = {'upvotedPosts': {itemId: item._id}};
      break;
    case "cancelDownvote":
      update.$pull = {'downvotedPosts': {itemId: item._id}};
      break;
  }

  Users.update({_id: user._id}, update);

}

addCallback("upvote.async", updateUser);
addCallback("downvote.async", updateUser);
addCallback("cancelUpvote.async", updateUser);
addCallback("cancelDownvote.async", updateUser);


/**
 * @summary Update the karma of the item's owner
 * @param {object} item - The item being operated on
 * @param {object} user - The user doing the operation
 * @param {object} collection - The collection the item belongs to
 * @param {string} operation - The operation being performed
 */
function updateKarma(item, user, collection, operation, context) {

  const votePower = getVotePower(user);
  const karmaAmount = (operation === "upvote" || operation === "cancelDownvote") ? votePower : -votePower;

  // only update karma is the operation isn't done by the item's author
  if (item.userId !== user._id) {
    Users.update({_id: item.userId}, {$inc: {"karma": karmaAmount}});
  }

}

addCallback("upvote.async", updateKarma);
addCallback("downvote.async", updateKarma);
addCallback("cancelUpvote.async", updateKarma);
addCallback("cancelDownvote.async", updateKarma);


// ----------------------- posts.new.async --------------------------------- //
// ----------------------- comments.new.async ------------------------------ //

/**
 * @summary Run the "upvote.async" callbacks *once* the item exists in the database
 * @param {object} item - The item being operated on
 * @param {object} user - The user doing the operation
 * @param {object} collection - The collection the item belongs to
 */
function UpvoteAsyncCallbacksAfterDocumentInsert(item, user, collection) {
  runCallbacksAsync("upvote.async", item, user, collection, 'upvote', 'new');
}

addCallback("posts.new.async", UpvoteAsyncCallbacksAfterDocumentInsert);
addCallback("comments.new.async", UpvoteAsyncCallbacksAfterDocumentInsert);