"use strict";

//! {"permissions": ["network"], "require": ["libencoding", "libhttp"]}

let libhttp = require("libhttp");

async function getEvents() {
	let now = new Date();
	let cacheVersion = "1-" + now.toDateString();
	if (await database.get("cacheVersion") != cacheVersion) {
		terminal.print("Refreshing database...");
		let keys = await database.getAll();
		await Promise.all(keys.map(x => database.remove(x)));
		await database.set("cacheVersion", cacheVersion);
	}
	let events = [];
	let url = "https://api.meetup.com/The-Most-Informal-Running-Club-Ever-TMIRCE-Upstate/events?&sign=true&photo-host=public&status=past";
	let done = false;
	while (!done) {
		let response;
		response = await database.get(url);
		if (response) {
			response = JSON.parse(response);
		}
		if (!response) {
			response = await libhttp.get(url);
			await database.set(url, JSON.stringify(response));
		}
		let nextLink;
		let theseEvents = JSON.parse(response.body);
		for (let j in theseEvents) {
			if (new Date(theseEvents[j].time) < now) {
				events.push(theseEvents[j]);
			} else {
				done = true;
				break;
			}
		}
		for (let j in response.headerArray) {
			let link = response.headerArray[j];
			if (link[0] == "Link" && link[1].split("; ")[1] == 'rel="next"') {
				link = link[1].split("; ")[0];
				link = link.substring(1, link.length - 1);
				nextLink = link;
			}
		}
		if (nextLink) {
			url = nextLink;
		} else {
			break;
		}
	}
	return events;
}

async function trackWorkouts(events) {
	let results = [];
	for (let i in events) {
		let event = events[i];
		if (event && event.venue && event.venue.name
			&& new Date(event.time).getDay() == 1) {
			let match = /follow (?:my|our) (.*?) workout/.exec(event.description);
			let workout;
			if (match) {
				workout = match[1];
			} else if (/snowshoe/.exec(event.description)
				|| /No run/.exec(event.description)) {
				// nothing
			} else {
				results.push(event.description);
			}
			if (workout) {
				results.push(workout);
			}
		}
	}
	return results;
}

async function locationByDay(day, events) {
	let results = [];
	for (let i in events) {
		let event = events[i];
		if (event && event.venue && event.venue.name
			&& new Date(event.time).getDay() == day) {
			results.push(event.venue.name);
		}
	}
	return results;
}

async function redisplay(action, filter, actions, filters, events) {
	//terminal.cork();
	terminal.clear();
	if (actions[action]) {
		terminal.setHash(action);
		terminal.print({style: "font-size: xx-large", value: action});
	}
	terminal.print("What:");
	for (let i in actions) {
		terminal.print(action == i ? "-> " : " * ", {command: i});
	}
	terminal.print("How:");
	for (let i in filters) {
		terminal.print(filter == i ? "-> " : " * ", {command: i});
	}
	terminal.print("--");
	if (actions[action]) {
		filters[filter](await actions[action](events));
	}
	//terminal.uncork();
}

function rawFilter(items) {
	for (let i in items) {
		terminal.print(items[i]);
	}
}

function histogramFilter(items) {
	let table = {};
	for (let i in items) {
		if (!table[items[i]]) {
			table[items[i]] = 0;
		}
		table[items[i]] += 1;
	}

	let results = [];
	for (let i in table) {
		results.push([table[i], i]);
	}
	results.sort((x, y) => y[0] - x[0]);

	for (let i in results) {
		terminal.print(results[i][0].toString(), " ", results[i][1]);
	}
}

async function main() {
	terminal.print("loading events...");
	let events = await getEvents();
	terminal.print("loaded ", events.length.toString(), " events");

	let actions = {
		"Sunday Locations": locationByDay.bind(null, 0),
		"Monday Track Workouts": trackWorkouts,
		"Tuesday Locations": locationByDay.bind(null, 2),
		"Wednesday Locations": locationByDay.bind(null, 3),
		"Thursday Locations": locationByDay.bind(null, 4),
		"Friday Locations": locationByDay.bind(null, 5),
		"Saturday Locations": locationByDay.bind(null, 6),
	}

	let filters = {
		"Chronological": rawFilter,
		"Histogram": histogramFilter,
	};

	let action = null;
	let filter = "Chronological";

	core.register("hashChange", function(event) {
		if (event.hash && event.hash[0] == '#') {
			terminal.clear();
			let hash = event.hash.substring(1);
			if (filters[hash]) {
				filter = hash;
			} else if (actions[hash]) {
				action = hash;
			}
			redisplay(action, filter, actions, filters, events);
		}
	});

	while (true) {
		redisplay(action, filter, actions, filters, events);
		let command = await terminal.readLine();
		if (filters[command]) {
			filter = command;
		} else if (actions[command]) {
			action = command;
		}
	}
}

main().catch(terminal.print);