commonly-used/refactorably-pending scripts/gists/snippets

# BASH SNIPPETS (basics, ffmpeg, calibre, rename)

# bash basics
cat helloworld.py | pbcopy
curl "example.com/examle.py" --output example.py
wget -i example.txt # wget is curl but can take list of files as input

# ffmpeg/calibre
ffmpeg -i video.webm video.mp4
ffmpeg -i filename.mp4 filename.mp3
ffmpeg -f gif -i seal.gif seal.mp4
ffmpegpdf myfile.pdf myfile.mp4
ebook-convert myfile.epub myfile.pdf # why does the converted pdf have reversed copy-able/find-able text?

# ffmpeg one directory - reduce video scale for all mkv files in a directory (adapted from https://unix.stackexchange.com/questions/28803/how-can-i-reduce-a-videos-size-with-ffmpeg)
# variable fraction 2 = one half, 3 = one third, four = one fourth, 5 = one fifth, etc...
fraction=2; for i in *.mkv; do ffmpeg -i "$i" -vf "scale=trunc(iw/(2*$fraction))*2:trunc(ih/(2*$fraction))*2" -c:v libx265 -crf 28 "$i.mobile.mp4"; done
# ffmpeg broader - reduce video scale for mkv or mp4 or avi files recursively (zShell/zsh solution)
fraction=2; setopt extended_glob; for i in **/*.(mkv|mp4|avi); do ffmpeg -i "$i" -vf "scale=trunc(iw/(2*$fraction))*2:trunc(ih/(2*$fraction))*2" -c:v libx265 -crf 28 "$i:r.mobile.mp4"; done

# RENAMING FILES - perl rename utility
# to install: "brew install rename"
# use the rename -n flag to test what files will be renamed, remove it to 'go live'!
# ([0-9]+) / [a-zA-Z0-9]{8} = matches digits infinitely (+) and alphanumeric 8 length
# SIMPLE RENAMING FILES:
# For example following command will prepend string MyVacation2011_ to all the files with jpg extension.
rename -n 's/^/MyVacation2011_/g' *.jpg
# MORE COMPLICATED RENAMING FILES:
# to rename "[gg]_Hetalia_Axis_Powers_-_01_[Webcast]_[047F1273].mkv" to "Hetalia 01.mkv", use this:
rename -n 's/\[gg\]_Hetalia_Axis_Powers_-_([0-9]+)_\[Webcast\]_\[[a-zA-Z0-9]{8}\]/Hetalia $1/g' *.mkv
# to rename "[AnimeRG] Hetlia - 54 [480p] [Xcelent].mp4" to "Hetalia 54.mkv", use this:
rename -n 's/\[gg\]_Hetalia_Axis_Powers_-_([0-9]+)_\[Webcast\]_\[[a-zA-Z0-9]{8}\]/Hetalia $1/g' *.mkv
# GENERIC RENAME SOLUTION FOR MY PERSONAL PURPOSES
rename 's/\.mobile\.mp4$/.mp4/' *.mobile.mp4
rename -n 's/(.+)\.mobile\.mp4$/$1.mp4/' *.mobile.mp4

// JAVASCRIPT SNIPPETS
// 4x js
domLoadScripts_Link=function(t){Array.isArray(t)||(t=[t]),t.forEach((function(t){var e=document.getElementsByTagName("head")[0],r=document.createElement("script");r.setAttribute("src",t.trim()),e.appendChild(r)}))};
// load scripts
domLoadScripts_Link(["https://yayinternets.github.io/datascripts.js", "https://yayinternets.github.io/domscripts.js"]);
domLoadStyles_Link("https://yayinternets.github.io/datacss.css");
copy(toTabDelimited(dom_deconstructDOM()));

// basic js
for (i=0;i<10;i++){ /* code */ }
setTimeout(() => { console.log("Delayed for 1 second."); }, 1000)
min=0; max=20; min = Math.ceil(min); max = Math.floor(max+1); Math.floor(Math.random() * (max - min) + min); // min/max inclusive, via getRandomInt
  
// js dom
document.querySelectorAll("[data-foo='1']"); // data elements
var test = document.querySelectorAll('input[value][type="checkbox"]:not([value=""])'); // = get all inputs with the attribute "value" and has the attribute "value" that is not blank.
var awaitingSetTimeout = async (iMs) => new Promise((resolve) => setTimeout(() => { "code"; resolve('done') }, iMs )); await awaitingSetTimeout(1000);

<style>body { background-image: linear-gradient(to bottom, rgba(245, 246, 252, 0.90), rgba(255, 153, 230, 0.73)), url('https://i.imgur.com/b5Z6ZNG.jpg'); background-repeat: repeat; } </style>
body { background-image: url(https://i.imgur.com/JNnR9lh.jpg); background-size: 100% 100%; }

<script type="text/javascript">document.addEventListener("DOMContentLoaded", function(event) { /* code */ }); </script>
<script type="text/javascript">document.addEventListener("DOMContentLoaded", function(event) { setTimeout(() => { /* code */ }, "1000"); }); </script>
<script src="https://yayinternets.github.io/datascripts.js"></script>
<script src="https://yayinternets.github.io/domscripts.js"></script>
<link rel="stylesheet" href="https://yayinternets.github.io/datacss.css">

// for loop one-liner
for (i=2e3;i--;){console.log("blah");}
// head DOMContentLoaded
<script type="text/javascript">document.addEventListener("DOMContentLoaded", function(event) { "insert_here"; }); </script>

// background tessellation with gradient white-pink fade
domLoadStyles_CSS(`
body {
  background-image: linear-gradient(to bottom, rgba(245, 246, 252, 0.90), rgba(255, 153, 230, 0.73)),
    url('https://i.imgur.com/uRy9AbZ.png');
  background-repeat: repeat;
  
}
`)

// more promises 
const user = await getUser();
const products = await getProducts();
 vs
const [user, products] = await Promise.all([
getUser(), getProducts()
i);

// 4 Ways to make async function process asynchronously and wait for each other to finish after another based on an initial Array
// via https://stackoverflow.com/questions/40328932/javascript-es6-promise-for-loop/40329190
// javascript 12/28 notes asynch "cascacding"? - refactor into domscripts.notes/hints?

aArray = $$$a(".btnsubmit_single_transfer");

// With reduce
aArray.reduce((a,e,i)=>{
    return a.then(() => submit_single_transfer(e))
     .then(() => console.log(i))
}, Promise.resolve() );

// With for loop
for (let i = 0, p = Promise.resolve(); i < aArray.length; i++) {
    p = p.then(() => submit_single_transfer(aArray[i]))
         .then(() => console.log(i));
}

// With a function passing itself as resolution-callback
(function loop(i) {
    if (i >= aArray.length) return; // all done
    submit_single_transfer(aArray[i]).then(() => {
        console.log(i);
        loop(i+1);
    });
})(0);

// With async/await
(async function loop() {
    for (let i = 0; i < aArray.length; i++) {
        await submit_single_transfer(aArray[i]);
        console.log(i);
    }
})();

// regex (javascript)
var rTimeStamps; `eg 12:34 11:11`.match(/[0-9]+\:[0-9]+/g).sort().join(" "); // match timestamps for youtube
var rURLs; `https://www.whatever.com https://www.example.com`.match(/(https?:\/\/[^\s]+)/g);

supersnippets tinyurl - http://tinyurl.com/supersnippets (self)
Vulnerable Code Snippets flexboxfroggy gridgarden helloworld extravaganza
# prototypes * [linktree](https://theoryoftheory.github.io/linktree.htm) * [organize code snippets?](https://www.reddit.com/r/webdev/comments/sq6vto/looking_for_a_way_to_organize_code_snippets/) * [a.singlediv.com](https://a.singlediv.com/)