Trail Difficulty by Date from Summary

[abkfenris]

It would be nice to have a stacked bar that showed the amounts of trails open by difficulty by date

var summary,
    dates = {};

d3.json('/api/summary', function(data) {
	summary = data;

	summary.conditions.forEach(function(c) {
		if (undefined === dates[c.datetime]) {
			dates[c.datetime] = {}
		}
		if (undefined === dates[c.datetime][c.difficulty]) {
			dates[c.datetime][c.difficulty] = {}
		}
		if (undefined == dates[c.datetime][c.difficulty][c.open]) {
			dates[c.datetime][c.difficulty][c.open] = 0
		}
		dates[c.datetime][c.difficulty][c.open] += c.trail_count
	});
});

Builds a dictionary of datetimes with with difficulty and the amount of runs open and closed

{"Fri, 02 Dec 2016 08:25:00 GMT": {
    "beginner": {"true": 2, "false": 31}, 
    "black": {"true": 2, "false": 34},
    "double-black": {"false": 37},
    "intermediate": {"true": 4, "false": 43},
}