function ignoreInjectionError() {
	if (chrome.runtime.lastError) {
		return;
	}
}

function includeFiles(tabID) {
	chrome.scripting.executeScript({
		target: { tabId: tabID },
		files: [ 'files/script/jquery-3.2.1.min.js' ]
	}, function() {
		if (chrome.runtime.lastError) {
			return;
		}

		chrome.scripting.executeScript({
			target: { tabId: tabID },
			files: [ 'files/script/postload.js' ]
		}, ignoreInjectionError);

		chrome.scripting.insertCSS({
			target: { tabId: tabID },
			files: [ 'files/css/style.css' ]
		}, ignoreInjectionError);
	});
}

function includeFilesInOpenYouTubeTabs() {
	chrome.tabs.query({
		url: [ '*://youtube.com/*', '*://www.youtube.com/*' ]
	}, function(tabs) {
		for (var i = 0; i < tabs.length; i++) {
			includeFiles(tabs[i].id);
		}
	});
}

chrome.runtime.onInstalled.addListener(includeFilesInOpenYouTubeTabs);
chrome.runtime.onStartup.addListener(includeFilesInOpenYouTubeTabs);