// ==UserScript==
// @name        SteamHistoryLowestPrice
// @namespace   SteamHistoryLowestPrice@Byzod.user.js
// @description 显示游戏在各种商店中当前和历史最低价格及进包次数
// @include     /^https?:\/\/store\.steampowered\.com\/app\/\d+/
// @version     2017-6-24
// @grant       GM_xmlhttpRequest
// jshint esversion:6
// @downloadURL none
// ==/UserScript==

// 货币符号
const CURRENCY_SYMBOLS = {
	'AED': 'DH',
	'AUD': 'A$',
	'BRL': 'R$',
	'CAD': 'CDN$',
	'CHF': 'CHF',
	'CLP': 'CLP$',
	'CNY': '¥',  // Chines Yuan
	'COP': 'COL$',
	'CRC': '₡',    // Costa Rican Colón
	'EUR': '€',    // Euro
	'GBP': '£',    // British Pound Sterling
	'HKD': 'HK$',
	'IDR': 'Rp',
	'ILS': '₪',    // Israeli New Sheqel
	'INR': '₹',    // Indian Rupee
	'JPY': '¥',    // Japanese Yen
	'KRW': '₩',    // South Korean Won
	'MXN': 'Mex$',
	'MYR': 'RM',
	'NGN': '₦',    // Nigerian Naira
	'NOK': 'kr',
	'NZD': 'NZ$',
	'PEN': 'S/.',
	'PHP': '₱',    // Philippine Peso
	'PLN': 'zł',   // Polish Zloty
	'PYG': '₲',    // Paraguayan Guarani
	'RUB': 'pуб',
	'SAR': 'SR',
	'SGD': 'S$',
	'THB': '฿',    // Thai Baht
	'TRY': 'TL',
	'TWD': 'NT$',
	'UAH': '₴',    // Ukrainian Hryvnia
	'USD': '$',    // US Dollar
	'VND': '₫',    // Vietnamese Dong
	'ZAR': 'R ',
};
// 查询历史低价包括的商店
const STORES = [
	"steam",
	"amazonus",
	"impulse",
	"gamersgate",
	"direct2drive",
	"origin",
	"uplay",
	"indiegalastore",
	"gamesplanet",
	"indiegamestand",
	"gog",
	"nuuvem",
	"dlgamer",
	"humblestore",
	"squenix",
	"bundlestars",
	"fireflower",
	"humblewidgets",
	"newegg",
	"coinplay",
	"wingamestore",
	"macgamestore",
	"gamebillet",
	"silagames",
	"itchio",
	"gamejolt",
	"paradox"
];


// 在app页和愿望单页显示史低价格
let appId = location.href.match(/app\/(\d+)/)[1];
// console.log('[史低]: appid = ' + appId + ', requesting data info...'); // DEBUG
let cc = "cn";
let ccMatch = document.cookie.match(/steamCountry=([a-z]{2})/i);
if (ccMatch !== null && ccMatch.length == 2) {
	cc = ccMatch[1];
}

// console.log('[史低]: request ' + appId + ' (' + cc + ') stores : %o', STORES); // DEBUG
AddLowestPriceTag(appId, STORES.join(","), cc, location.protocol);

// 在商店页添加史低信息
async function AddLowestPriceTag(appId, stores = "steam", cc = "cn", protocol = "https"){
	let data = null;
	let buyBtn = document.querySelector(".game_purchase_action");
	let lowestInfo = document.createElement("div");
	
	// 读取中……
	lowestInfo.className = "game_lowest_price";
	lowestInfo.innerText = "正在读取历史最低价格...";
	// 插到购买按钮上面
	if(buyBtn){
		buyBtn.prepend(lowestInfo);
	}
	
	try {
		data = JSON.parse( await GettingSteamDBAppInfo(appId, stores, cc, protocol) );
	} catch (err) {
		console.log('[史低]: ' + err);
	}
	
	// console.log('[史低]: app data ' + appId + ' : %o', data); // DEBUG
	
	let appInfo = data["app/" + appId];
	let metaInfo = data[".meta"];
	
	// 如果查到info，并且有价格，塞到第一个购买按钮上面去
	if(buyBtn && metaInfo && appInfo && appInfo.price && appInfo.lowest){
		let currencySymbol = metaInfo.currency in CURRENCY_SYMBOLS 
			? CURRENCY_SYMBOLS[metaInfo.currency] 
			: metaInfo.currency;
		
		lowestInfo.innerHTML = 
			// 历史最低
			'历史最低价是 '
			+ '<span style="cursor:help;text-decoration:underline;" title="' + appInfo.lowest.recorded_formatted + '">'
				+ new Date(appInfo.lowest.recorded * 1e3).toLocaleDateString()
			+ '</span>&nbsp;时在&nbsp;'
			+ '<a target="_blank" href="' + appInfo.lowest.url + '"> '
				+ appInfo.lowest.store
			+ '</a>&nbsp;中的&nbsp;'
			+ '<span class="discount_pct">-' + appInfo.lowest.cut + '%</span>'
			+ '<a target="_blank" title="查看价格历史" href="' + appInfo.urls.history + '"> '
				+ currencySymbol + ' ' + appInfo.lowest.price
			+ '</a>'

			// 第二行
			+ '<br />'

			// 进包次数
			+ '进包&nbsp;<a target="_blank" title="查看进包信息"  href="' + appInfo.urls.bundles + '"'
				+ (appInfo.bundles && appInfo.bundles.live.length > 0
					? ' style="color:#0d0" title="' + appInfo.bundles.live.length + ' 个正在销售的慈善包"'
					: '')
				+'> ' 
				+ appInfo.bundles.count
			+ ' </a>&nbsp;次，'

			// 当前最低
			+ (appInfo.price.price <= appInfo.lowest.price
				? '<span class="game_purchase_discount_countdown">当前为历史最低价</span>，'
				: '<span>当前最低价是</span>' )
			+ '在&nbsp;'
			+ '<a target="_blank" href="' + appInfo.price.url + '"> '
				+ appInfo.price.store
			+ '</a>&nbsp;中的&nbsp;'
			+ '<span class="discount_pct">-' + appInfo.price.cut + '%</span>'
			+ '<a target="_blank" title="查看价格信息"  href="' + appInfo.urls.info + '"> '
				+ currencySymbol + ' ' + appInfo.price.price
			+ '</a>';
	}
	
	// 返回史低info
	return Promise.resolve(lowestInfo);
}

// 获取史低信息
async function GettingSteamDBAppInfo(appId, stores = "steam", cc = "cn", protocol = "https"){
	let requestPromise = null;
	
	if(!isNaN(appId) && parseInt(appId) > 0){
		requestPromise = new Promise( (resolve, reject) => {
			GM_xmlhttpRequest({
				method: "GET",
				url: protocol + "//api.enhancedsteam.com/pricev3/?appid=" + appId + "&stores=" + stores + "&cc=" + cc,
				onload: function (response) {
					resolve(response.response);
				},
				onerror: function (error) {
					reject(error);
				}
			});
		});
	} else {
		requestPromise = Promise.reject("Invalid appid");
	}
	
	return requestPromise;
}