With all the images hosted on Amazon s3, and the tag data hosted on parse.com, I created a simple page where users can explore the candidates’ images by topic and by candidate. The default is all topics and all candidates, but users can narrow the selection of images displayed by making multiple selections from each field. Additionally, more images will load as you scroll down the page.

Unfortunately, the AI-enabled image tagging doesn’t always work as well as one might hope.

Here’s the page’s JavaScript code:

var name2slug = {};
var slug2name = {};

Array.prototype.remove = function() {
    var what, a = arguments, L = a.length, ax;
    while (L && this.length) {
        what = a[--L];
        while ((ax = this.indexOf(what)) !== -1) {
            this.splice(ax, 1);
        }
    }
    return this;
}

Array.prototype.chunk = function(chunkSize) {
    var array=this;
    return [].concat.apply([],
        array.map(function(elem,i) {
            return i%chunkSize ? [] : [array.slice(i,i+chunkSize)];
        })
    );
}

function dateFromString(str) {
	var m = str.match(/(\d+)-(\d+)-(\d+)T(\d+):(\d+):(\d+)Z/);
	var date = new Date(Date.UTC(+m[1], +m[2], +m[3], +m[4], +m[5], +m[6]));
	var options = {
	    weekday: "long", year: "numeric", month: "short",
	    day: "numeric", hour: "2-digit", minute: "2-digit"
	};
	return date.toLocaleTimeString("en-us", options);
}

function updatePhotos(query) {
	$.ajax({
		url: 'https://api.parse.com/1/classes/all_photos?limit=1000&where='+JSON.stringify(query),
		type: 'GET',
		dataType: 'json',
		success: function(response) {
			// console.log(response);
			$('#img-container').empty();

			var curChunk = 0;
			var resultChunks = response['results'].chunk(30);

			function appendPhotos(chunkNo) {

				resultChunks[chunkNo].map(function(obj){
					var date = dateFromString(obj['datetime'])
					var imgUrl = "https://s3-us-west-2.amazonaws.com/electionscrape/" + obj['source'] + "/400px_" + obj['filename'];
					var fullImgUrl = "https://s3-us-west-2.amazonaws.com/electionscrape/" + obj['source'] + "/" + obj['filename'];
					$('#img-container').append(
						$('<div class=\"grid-item\"></div>').append(
							'<a href=\"'+fullImgUrl+'\"><img src=\"'+imgUrl+'\" width=\"280px\"></a><p>'+slug2name[obj['candidate']]+'</p><p>'+date+'</p><p>'+obj['source']+'</p>'
						) // not a missing semicolon
					);
					// console.log(obj['candidate']);
					// console.log(obj['datetime']);
					// console.log(obj['source']);
					// console.log(obj['filename']);
				});

			}

			appendPhotos(curChunk);

			window.onscroll = function(ev) {
			    if ((window.innerHeight + window.scrollY) >= document.body.offsetHeight) {
			        curChunk++;
			        appendPhotos(curChunk);
			    }
			};


		},
		error: function(response) { "error" },
		beforeSend: setHeader
	});
}

function setHeader(xhr) {
	xhr.setRequestHeader("X-Parse-Application-Id", "ID-GOES-HERE");
	xhr.setRequestHeader("X-Parse-REST-API-Key", "KEY-GOES-HERE");
}

function makeQuery(candArr, tagArr) {

	orArr = tagArr.map(function(tag){
		return { "tags": tag };
	})

	if (tagArr.length === 0 && candArr.length > 0) {
		var query = {
			'candidate': {"$in": candArr}
		};
	}
	else if (tagArr.length > 0 && candArr.length === 0) {
		var query = {
			'$or': orArr
		};
	}
	else if (tagArr.length === 0 && candArr.length === 0) {
		var query = {};
	}
	else {
		var query = {
			'candidate': {"$in": candArr},
			'$or': orArr
		};
	}

	updatePhotos(query);

}

(function(){

$('.grid').masonry({
  // options
  itemSelector: '.grid-item',
  columnWidth: 300
});

var selectedCandidates = [];
var selectedTags = [];

$.getJSON("data/candidates.json", function(data){
	var candNames = Object.keys(data).map(function(slug){
		var name = data[slug]['name'];
		name2slug[name] = slug;
		slug2name[slug] = name;
		return name;
	}).sort();

	candNames.map(function(name){
		$('#candidate-dropdown').append(
			'<li class=\"candidate-item\"><a href=\"#\">'+name+'</a></li>'
		);
	});

	$('.candidate-item').click(function(){
		var name = $(this).text();
		var slug = name2slug[name];
		if ($.inArray(slug, selectedCandidates) === -1) {
			selectedCandidates.push(slug);
			makeQuery(selectedCandidates, selectedTags);
			console.log(selectedCandidates);
			$('#selected-candidates').append(
				$('<button class=\"btn btn-danger btn-xs cand-select-btn\"><span class=\"glyphicon glyphicon-remove\" aria-hidden=\"true\"></span>'+name+'</button>')
					.click(function(){
						$(this).fadeOut("fast", function(){
							selectedCandidates.remove(name2slug[$(this).text()]);
							makeQuery(selectedCandidates, selectedTags);
							console.log(selectedCandidates);
						});
					}) // THIS IS NOT A MISSING SEMI-COLON
			);
		}
	});
});


$.getJSON("data/tags.json", function(data){
	var tags = data["tags"].sort();
	tags.map(function(tag){
		$('#tag-dropdown').append(
			'<li class=\"tag-item\"><a href=\"#\">'+tag+'</a></li>'
		);
	});

	$('.tag-item').click(function(){
		var tag = $(this).text();
		if ($.inArray(tag, selectedTags) === -1) {
			selectedTags.push(tag);
			makeQuery(selectedCandidates, selectedTags);
			console.log(selectedTags);
			$('#selected-tags').append(
				$('<button class=\"btn btn-primary btn-xs tag-select-btn\"><span class=\"glyphicon glyphicon-remove\" aria-hidden=\"true\"></span>'+tag+'</button>')
					.click(function(){
						$(this).fadeOut("fast", function(){
							selectedTags.remove($(this).text());
							makeQuery(selectedCandidates, selectedTags);
							console.log(selectedTags);
						});
					})
			);
		}
	});
});

makeQuery(selectedCandidates, selectedTags);

})();