An attempt at a paging implementation for use with embersmith

folder_structure.txt

contents
  \posts
    \2013
      \first-post.md
      \second-post.md
    \2014
      \third-post.md
      \fourth-post.md

pager.hbs

{{{ pager contents.posts title date }}}

pager.js

var _ = require('lodash'),
  moment = require('moment');

var getPost = function getPost(postArray, index) {
  if(index < 0 || index >= postArray.length)
    return null;
  else
    return postArray[index];
};

module.exports = function( item, currentTitle, currentDate ) {
  var posts = [];

  _.forEach(item, function(yearContents, year) {
    var postsFromYear = _(item[year]).keys().remove(function(item) {
      return "index.md" !== item;
    });

    postsFromYear.forEach(function(postFileName) {
      var postObj = item[year][postFileName];
      
      var meta = postObj.metadata;
      var rtn = {
        date: new moment(meta.date),
        title: meta.title,
        url: postObj.url
      };

      posts.push(rtn);
    });
  });

  var sortedPosts = _(posts).sortBy(function(item) {
    return item.date.unix();
  });

  var foundIndex = sortedPosts.findIndex(function(post) {
    var isSameTitle = post.title === currentTitle;
    var isSameDate = (new moment(currentDate)).unix() === post.date.unix();

    return isSameTitle && isSameDate;
  }).valueOf();
  sortedPosts = sortedPosts.valueOf();

  var previousPost = getPost(sortedPosts, foundIndex - 1);
  var nextPost = getPost(sortedPosts, foundIndex + 1);

  var rtnMarkup = [];
  rtnMarkup.push('<ul class="pager">');
  if (previousPost) {
    rtnMarkup.push('<li class="previous"><a href="' + previousPost.url + '">&larr; ' + previousPost.title + '</a></li>');
  }
  if (nextPost) {
    rtnMarkup.push('<li class="next"><a href="' + nextPost.url + '">' + nextPost.title + ' &rarr;</a></li>');
  }
        
  rtnMarkup.push('</ul>');

  return rtnMarkup.join('\n');
}