//external lib imports
const GetUrls = require("get-urls"); //for extracting urls from messages

//my imports
const DiscordUtil = require("discordjs-util");

//app component imports
const GuildData = require("./models/guild-data.js");
const FeedData = require("./models/feed-data.js");

module.exports = {
	onReady(client, guildsData, config) {
		return new Promise((resolve, reject) => {
			parseLinksInGuilds(client.guilds, guildsData)
				.then(() => checkFeedsInGuilds(client.guilds, guildsData))
				.then(() => setInterval(() => checkFeedsInGuilds(client.guilds, guildsData), config.feedCheckIntervalSec * 1000)); //set up an interval to check all the feeds
		});
	},
	onCommand(commandObj, commandsObj, params, guildData, message, config, client, botName) {
		switch (commandObj.command) {
			case commandsObj.addFeed.command:
				return addFeed(client, guildData, message, config.maxCacheSize);
			case commandsObj.removeFeed.command:
				return removeFeed(guildData, message, botName);
			case commandsObj.viewFeeds.command:
				return viewFeeds(guildData);
		}
	},
	onNonCommandMsg(message, guildData) {
		guildData.feeds.forEach(feedData => {
			if (message.channel.name === feedData.channelName)
				feedData.cachedLinks.push(...GetUrls(message.content)); //spread the urlSet returned by GetUrls into the cache array
		});
	}
};

function addFeed(client, guildData, message, maxCacheSize) {
	return new Promise((resolve, reject) => {
		const feedUrl = [...GetUrls(message.content)][0];
		const channel = message.mentions.channels.first();

		if (!feedUrl || !channel)
			reject("Please provide both a channel and an RSS feed URL. You can optionally @mention a role also.");

		const role = message.mentions.roles.first();

		const feedData = new FeedData({
			url: feedUrl,
			channelName: channel.name,
			roleName: role ? role.name : null,
			maxCacheSize: maxCacheSize
		});

		//ask the user if they're happy with the details they set up, save if yes, don't if no
		DiscordUtil.ask(client, message.channel, message.member, "Are you happy with this?\n" + feedData.toString())
			.then(responseMessage => {

				//if they responded yes, save the feed and let them know, else tell them to start again
				if (responseMessage.content.toLowerCase() === "yes") {
					if (!guildData)
						guildData = new GuildData({ id: message.guild.id, feeds: [] });

					guildData.feeds.push(feedData);
					resolve("Your new feed has been saved!");
				}
				else
					reject("Your feed has not been saved, please add it again with the correct details");
			});
	});
}

function removeFeed(guildData, message, botName) {
	return new Promise((resolve, reject) => {
		const parameters = message.content.split(" ");
		if (parameters.length !== 3)
			resolve(`Please use the command as such:\n\`\`\` ${botName} remove-feed feedid\`\`\``);
		else {
			const idx = guildData.feeds.findIndex(feed => feed.id === parameters[2]);
			if (!Number.isInteger(idx))
				reject("Can't find feed with id " + parameters[2]);
			else {
				guildData.feeds.splice(idx, 1);
				resolve("Feed removed!");
			}
		}
	});
}

function viewFeeds(guildData) {
	if (!guildData)
		return Promise.reject("Guild not setup");

	return Promise.resolve(guildData.feeds.map(f => f.toString()).join("\n"));
}

function checkFeedsInGuilds(guilds, guildsData) {
	Object.keys(guildsData).forEach(key => guildsData[key].checkFeeds(guilds));
}

function parseLinksInGuilds(guilds, guildsData) {
	const promises = [];
	for (let guildId of guilds.keys()) {
		const guildData = guildsData[guildId];
		if (guildData)
			promises.push(guildData.cachePastPostedLinks(guilds.get(guildId)));
	}
	return Promise.all(promises);
}