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diff --git a/downloaders.js b/downloaders.js
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+const { promisifyProcess } = require('./general-util')
+const { spawn } = require('child_process')
+const { promisify } = require('util')
+const fs = require('fs')
+const fse = require('fs-extra')
+const fetch = require('node-fetch')
+const tempy = require('tempy')
+const path = require('path')
+const sanitize = require('sanitize-filename')
+
+const writeFile = promisify(fs.writeFile)
+const copyFile = fse.copy
+
+// Pseudo-tempy!!
+/*
+const tempy = {
+  directory: () => './tempy-fake'
+}
+*/
+
+class Downloader {
+  download(arg) {}
+}
+
+// oh who cares about classes or functions or kool things
+
+const downloaders = {
+  extension: 'mp3', // Generally target file extension
+
+  http: arg => {
+    const out = (
+      tempy.directory() + '/' +
+      sanitize(decodeURIComponent(path.basename(arg))))
+
+    return fetch(arg)
+      .then(response => response.buffer())
+      .then(buffer => writeFile(out, buffer))
+      .then(() => out)
+  },
+
+  youtubedl: arg => {
+    const out = (
+      tempy.directory() + '/' + sanitize(arg) +
+      '.' + downloaders.extname)
+
+    const opts = [
+      '--quiet',
+      '--extract-audio',
+      '--audio-format', downloaders.extension,
+      '--output', out,
+      arg
+    ]
+
+    return promisifyProcess(spawn('youtube-dl', opts))
+      .then(() => out)
+      .catch(err => false)
+  },
+
+  local: arg => {
+    // Usually we'd just return the given argument in a local
+    // downloader, which is efficient, since there's no need to
+    // copy a file from one place on the hard drive to another.
+    // But reading from a separate drive (e.g. a USB stick or a
+    // CD) can take a lot longer than reading directly from the
+    // computer's own drive, so this downloader copies the file
+    // to a temporary file on the computer's drive.
+    // Ideally, we'd be able to check whether a file is on the
+    // computer's main drive mount or not before going through
+    // the steps to copy, but I'm not sure if there's a way to
+    // do that (and it's even less likely there'd be a cross-
+    // platform way).
+
+    // It's possible the downloader argument starts with the "file://"
+    // protocol string; in that case we'll want to snip it off and URL-
+    // decode the string.
+    const fileProto = 'file://'
+    if (arg.startsWith(fileProto)) {
+      arg = decodeURIComponent(arg.slice(fileProto.length))
+    }
+
+    // TODO: Is it necessary to sanitize here?
+    // Haha, the answer to "should I sanitize" is probably always YES..
+    const base = path.basename(arg, path.extname(arg))
+    const out = (
+      tempy.directory() + '/' + sanitize(base) + path.extname(arg))
+
+    return copyFile(arg, out)
+      .then(() => out)
+  },
+
+  echo: arg => arg,
+
+  getDownloaderFor: arg => {
+    if (arg.startsWith('http://') || arg.startsWith('https://')) {
+      if (arg.includes('youtube.com')) {
+        return downloaders.youtubedl
+      } else {
+        return downloaders.http
+      }
+    } else {
+      return downloaders.local
+    }
+  }
+}
+
+module.exports = downloaders