Plays audio associated with images via a URL in the filename on 4chan.
// ==UserScript==
// @name 4chan External Sounds
// @namespace b4k
// @description Plays audio associated with images via a URL in the filename on 4chan.
// @author Bakugo
// @version 1.0.0
// @match *://boards.4chan.org/*
// @run-at document-start
// ==/UserScript==
(function() {
var regexFileURL;
var regexTrigger;
var audioPlayers;
var processFile;
var processFiles;
var getFileKey;
var playFile;
regexFileURL = /\/\/i.4cdn.org\/(.+?)\/(\d+?)\.(.+?)$/;
regexTrigger = /\[audio[\|\$](.*?)\]/i;
audioPlayers = {};
document.addEventListener("4chanXInitFinished", function (event) {
if (!document.documentElement.classList.contains("fourchan-x")) {
return;
}
processFiles(document.body);
(new MutationObserver(function (mutations) {
mutations.forEach(function (mutation) {
if (mutation.type === "childList") {
mutation.addedNodes.forEach(function (node) {
if (node.nodeType === Node.ELEMENT_NODE) {
processFiles(node);
playFile(node);
}
});
}
});
})).observe(document.body, {
childList: true,
subtree: true
});
});
processFile = function (file) {
var fileLink;
var fileKey;
var fileName;
var fileNameEls;
var fileNameMatch;
var audioURL;
var audioPlayer;
if (!file.classList.contains("file")) {
return;
}
fileLink =
file.querySelector(".file-info > a");
if (!fileLink) {
return;
}
fileKey =
getFileKey(fileLink.href);
if (!fileKey) {
return;
}
fileName = null;
fileNameEls = [
file.querySelector(".file-info .fnfull"),
file.querySelector(".file-info > a")
];
fileNameEls.forEach(function (node) {
if (fileName) {
return;
}
if (node && node.textContent) {
fileName = node.textContent;
}
});
if (!fileName) {
return;
}
fileNameMatch =
fileName.match(regexTrigger);
if (!fileNameMatch) {
return;
}
audioURL = fileNameMatch[1];
audioURL = window.decodeURIComponent(audioURL);
audioURL = (audioURL.match(/^(https?\:)?\/\//) ? audioURL : ("http://" + audioURL));
audioPlayer = document.createElement("audio");
audioPlayer.src = audioURL;
audioPlayer.preload = "none";
audioPlayers[fileKey] = audioPlayer;
};
processFiles = 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) {
processFile(file);
});
});
};
getFileKey = function (fileURL) {
var fileURLMatch;
fileURLMatch =
fileURL.match(regexFileURL);
if (!fileURLMatch) {
return null;
}
return (fileURLMatch[1] + "." + fileURLMatch[2]);
};
playFile = function (target) {
var fileKey;
var audioPlayer;
var checkInterval;
if (!(target.id === "ihover" || target.className === "full-image")) {
return;
}
fileKey =
getFileKey(target.src);
if (!fileKey) {
return;
}
audioPlayer =
audioPlayers[fileKey];
if (!audioPlayer) {
return;
}
if (!audioPlayer.paused) {
return;
}
switch (target.tagName) {
case "IMG":
audioPlayer.currentTime = 0;
audioPlayer.loop = true;
audioPlayer.play();
break;
case "VIDEO":
audioPlayer.currentTime = target.currentTime;
audioPlayer.loop = false;
audioPlayer.play();
break;
default:
return;
}
checkInterval =
window.setInterval(function () {
if (document.body.contains(target)) {
if (target.tagName === "VIDEO") {
if (audioPlayer.duration) {
if (target.currentTime > audioPlayer.duration) {
audioPlayer.pause();
} else {
if (Math.abs(target.currentTime - audioPlayer.currentTime) > 0.1) {
audioPlayer.currentTime = target.currentTime;
}
if (!target.paused && audioPlayer.paused) {
audioPlayer.play();
}
if (target.paused && !audioPlayer.paused) {
audioPlayer.pause();
}
}
}
}
} else {
window.clearInterval(checkInterval);
audioPlayer.pause();
}
}, 10);
};
})();