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4chan External Sounds

Plays audio associated with images on 4chan.

// ==UserScript==
// @name 4chan External Sounds
// @namespace b4k
// @description Plays audio associated with images on 4chan.
// @author Bakugo
// @version 1.7.0
// @match *://boards.4chan.org/*
// @match *://boards.4channel.org/*
// @run-at document-start
// ==/UserScript==

(function() {
	var doInit;
	var doParseFile;
	var doParseFiles;
	var doPlayFile;
	var doMakeKey;
	
	var allow;
	var players;
	var isChanX;
	
	allow = [
		"4cdn.org",
		"catbox.moe",
		"dmca.gripe",
		"lewd.se",
		"pomf.cat",
		"zz.ht"
	];
	
	document.addEventListener(
		"DOMContentLoaded",
		function (event) {
			setTimeout(
				function () {
					if (
						document.body.classList.contains("ws") ||
						document.body.classList.contains("nws")
					) {
						isChanX = false;
						doInit();
					}
				},
				(1)
			);
		}
	);
	
	document.addEventListener(
		"4chanXInitFinished",
		function (event) {
			if (
				document.documentElement.classList.contains("fourchan-x") &&
				document.documentElement.classList.contains("sw-yotsuba")
			) {
				isChanX = true;
				doInit();
			}
		}
	);
	
	doInit = function () {
		var observer;
		
		if (players) {
			return;
		}
		
		players = {};
		
		doParseFiles(document.body);
		
		observer =
			new MutationObserver(
				function (mutations) {
					mutations.forEach(
						function (mutation) {
							if (mutation.type === "childList") {
								mutation.addedNodes.forEach(
									function (node) {
										if (node.nodeType === Node.ELEMENT_NODE) {
											doParseFiles(node);
											doPlayFile(node);
										}
									}
								);
							}
						}
					);
				}
			);
		
		observer
			.observe(
				document.body,
				{
					childList: true,
					subtree: true
				}
			);
	};
	
	doParseFile = function (file) {
		var fileLink;
		var fileName;
		var key;
		var match;
		var player;
		var link;
		
		if (!file.classList.contains("file")) {
			return;
		}
		
		if (isChanX) {
			fileLink = file.querySelector(".fileText .file-info > a");
		} else {
			fileLink = file.querySelector(".fileText > a");
		}
		
		if (!fileLink) {
			return;
		}
		
		if (!fileLink.href) {
			return;
		}
		
		fileName = null;
		
		if (isChanX) {
			[
				file.querySelector(".fileText .file-info .fnfull"),
				file.querySelector(".fileText .file-info > a")
			].some(
				function (node) {
					if (node) {
						if (node.textContent) {
							fileName = node.textContent;
							return true;
						}
					}
					
					return false;
				}
			);
		} else {
			[
				file.querySelector(".fileText"),
				file.querySelector(".fileText > a")
			].some(
				function (node) {
					if (node) {
						if (node.title) {
							fileName = node.title;
							return true;
						}
						
						if (
							node.tagName === "A" &&
							node.textContent
						) {
							fileName = node.textContent;
							return true;
						}
					}
					
					return false;
				}
			);
		}
		
		if (!fileName) {
			return;
		}
		
		fileName = fileName.replace(/\-/, "/");
		
		key = doMakeKey(fileLink.href);
		
		if (!key) {
			return;
		}
		
		if (players[key]) {
			return;
		}
		
		match = fileName.match(/[\[\(\{](?:audio|sound)[ \=\:\|\$](.*?)[\]\)\}]/i);
		
		if (!match) {
			return;
		}
		
		link = match[1];
		
		if (link.includes("%")) {
			try {
				link = decodeURIComponent(link);
			} catch (error) {
				return;
			}
		}
		
		
		if (link.match(/^(https?\:)?\/\//) === null) {
			link = (location.protocol + "//" + link);
		}
		
		try {
			link = new URL(link);
		} catch (error) {
			return;
		}
		
		if (
			allow.some(
				function (item) {
					return (
						link.hostname.toLowerCase() === item ||
						link.hostname.toLowerCase().endsWith("." + item)
					);
				}
			) == false
		) {
			return;
		}
		
		player = new Audio();
		
		player.preload = "none";
		player.volume = 0.80;
		player.loop = true;
		
		player.src = link.href;
		
		players[key] = player;
	};
	
	doParseFiles = function (target) {
		target.querySelectorAll(".post")
			.forEach(
				function (post) {
					if (post.parentElement.parentElement.id === "qp") {
						return;
					}
					
					if (post.parentElement.classList.contains("noFile")) {
						return;
					}
					
					post.querySelectorAll(".file")
						.forEach(
							function (file) {
								doParseFile(file);
							}
						);
				}
			);
	};
	
	doPlayFile = function (target) {
		var key;
		var player;
		var interval;
		
		if (isChanX) {
			if (!(
				target.id === "ihover" ||
				target.className === "full-image"
			)) {
				return;
			}
		} else {
			if (!(
				target.id === "image-hover" ||
				target.className === "expanded-thumb" ||
				target.className === "expandedWebm"
			)) {
				return;
			}
		}
		
		if (!target.src) {
			return;
		}
		
		key = doMakeKey(target.src);
		
		if (!key) {
			return;
		}
		
		player = players[key];
		
		if (!player) {
			return;
		}
		
		if (!player.paused) {
			if (player.dataset.play == 1) {
				if (isChanX) {
					return;
				} else {
					player.dataset.again = 1;
				}
			} else {
				player.pause();
			}
		}
		
		if (player.dataset.play != 1){
			player.dataset.play = 1;
			player.dataset.again = 0;
			player.dataset.moveTime = 0;
			player.dataset.moveLast = 0;
		}
		
		switch (target.tagName) {
			case "IMG":
				player.loop = true;
				
				if (player.dataset.again != 1) {
					player.currentTime = 0;
					player.play();
				}
				
				break;
			
			case "VIDEO":
				player.loop = false;
				player.currentTime = target.currentTime;
				player.play();
				break;
			
			default:
				return;
		}
		
		if (player.paused) {
			document.dispatchEvent(
				new CustomEvent(
					"CreateNotification",
					{
						bubbles: true,
						detail: {
							type: "warning",
							content: "Your browser blocked autoplay, click anywhere on the page to activate it and try again.",
							lifetime: 5
						}
					}
				)
			);
		}
		
		interval =
			setInterval(
				function () {
					if (document.body.contains(target)) {
						if (target.tagName === "VIDEO") {
							if (target.currentTime != (+player.dataset.moveLast)) {
								player.dataset.moveTime = Date.now();
								player.dataset.moveLast = target.currentTime;
							}
							
							if (player.duration != NaN) {
								if (
									target.paused == true ||
									target.duration == NaN ||
									target.currentTime > player.duration ||
									((Date.now() - (+player.dataset.moveTime)) > 300)
								) {
									if (!player.paused) {
										player.pause();
									}
								} else {
									if (
										player.paused ||
										Math.abs(target.currentTime - player.currentTime) > 0.100
									) {
										player.currentTime = target.currentTime;
									}
									
									if (player.paused) {
										player.play();
									}
								}
							}
						}
					} else {
						clearInterval(interval);
						
						if (player.dataset.again == 1) {
							player.dataset.again = 0;
						} else {
							player.pause();
							player.dataset.play = 0;
						}
					}
				},
				(1000/30)
			);
	};
	
	doMakeKey = function (link) {
		var match;
		
		match = link.match(/\.(?:4cdn|4chan)\.org\/(.+?)\/(\d+?)\.(.+?)$/);
		
		if (match) {
			return (match[1] + "." + match[2]);
		}
		
		return null;
	};
})();