From 6751f38ee365aa46bf53de0f9a09b91309bed377 Mon Sep 17 00:00:00 2001
From: Evert Prants <imsonotsleepy@gmail.com>
Date: Sun, 27 Jan 2019 00:35:09 +0200
Subject: [PATCH] track download from web interface

---
 src/common/download.js |  2 +-
 src/lastfm.js          | 49 +++++++++++++++++++++++++++++++++++++++---
 src/server.js          |  8 ++++++-
 3 files changed, 54 insertions(+), 5 deletions(-)

diff --git a/src/common/download.js b/src/common/download.js
index cefd1d7..c8d6393 100644
--- a/src/common/download.js
+++ b/src/common/download.js
@@ -58,7 +58,7 @@ function getVideoInfo (arg) {
 function fetchVideo (data) {
   return new Promise((resolve, reject) => {
     let tempName = path.join(process.cwd(), `/tmp.yt.${data.id}.mp3`)
-    ffmpeg(data.url)
+    ffmpeg(data.url || data.file)
       .audioCodec('libmp3lame')
       .format('mp3')
       .on('error', reject)
diff --git a/src/lastfm.js b/src/lastfm.js
index e637e4b..22a45c8 100644
--- a/src/lastfm.js
+++ b/src/lastfm.js
@@ -1,11 +1,15 @@
 import path from 'path'
-import as from './common/async'
+import asn from './common/async'
 import dl from './common/download'
 import crypto from 'crypto'
 
+const fs = require('fs').promises
 const values = require(path.join(process.cwd(), 'values.json'))
 
 let externalTracks = {}
+let downloadQueue = []
+let downloading = false
+let dbPromise
 
 function createHash (data) {
   return crypto
@@ -15,6 +19,21 @@ function createHash (data) {
     .substr(0, 8)
 }
 
+async function downloadLocally (id) {
+  let info = await getTrackMetaReal(id)
+  if (!info) throw new Error('No track with this ID in external list.')
+  let file = await dl.fetchVideo(info)
+  let filename = info.artist + ' - ' + info.title + '.mp3'
+  info.file = path.join(values.directory, filename)
+  await asn.promiseExec(`ffmpeg -i "${file.source}" -metadata artist="${info.artist}" -metadata title="${info.title}" -codec copy "${info.file}"`)
+  await fs.unlink(file.source)
+  let db = await dbPromise
+  let ins = await asn.insertDB(db, info)
+  if (!ins) {
+    throw new Error('A track of this description already exists in the database.')
+  }
+}
+
 async function getTrackMetaReal (id) {
   if (!id || !externalTracks[id]) return null
   let trdata = externalTracks[id]
@@ -40,7 +59,7 @@ async function search (track, limit = 30) {
 
   let data
   try {
-    data = await as.GET(`http://ws.audioscrobbler.com/2.0/?method=track.search&track=${track}&api_key=${values.lastfm}&format=json&limit=${limit}`)
+    data = await asn.GET(`http://ws.audioscrobbler.com/2.0/?method=track.search&track=${track}&api_key=${values.lastfm}&format=json&limit=${limit}`)
     data = JSON.parse(data)
 
     if (!data.results || !data.results.trackmatches || !data.results.trackmatches.track) {
@@ -74,4 +93,28 @@ async function search (track, limit = 30) {
   return final
 }
 
-export default {search, getTrackMetaReal}
+// Download thread
+let dltd = null
+function invokeDownload (add) {
+  if (add) downloadQueue.push(add)
+  if (dltd) return
+  dltd = setTimeout(function (argument) {
+    dltd = null
+    if (downloading) return invokeDownload()
+    if (!downloadQueue.length) return
+    downloading = true
+    downloadLocally(downloadQueue.shift()).then(() => {
+      downloading = false
+      if (downloadQueue.length) invokeDownload()
+    }).catch((e) => {
+      console.error(e)
+      downloading = false
+      if (downloadQueue.length) invokeDownload()
+    })
+  }, 2 * 1000)
+}
+
+export default function (db) {
+  dbPromise = db
+  return { search, getTrackMetaReal, invokeDownload }
+}
diff --git a/src/server.js b/src/server.js
index 2c61bd5..55f192f 100644
--- a/src/server.js
+++ b/src/server.js
@@ -6,7 +6,7 @@ import http from 'http'
 import https from 'https'
 import ffmpeg from 'fluent-ffmpeg'
 
-import lastfm from './lastfm'
+import lfmda from './lastfm'
 import remote from './remote-control'
 
 require('express-async-errors')
@@ -24,6 +24,8 @@ const port = process.env.PORT || 3000
 const dev = process.env.NODE_ENV === 'development'
 const server = http.createServer(app)
 
+const lastfm = lfmda(dbPromise)
+
 if (dev) {
   const morgan = require('morgan')
   app.use(morgan('dev'))
@@ -192,6 +194,10 @@ router.get('/serve/by-id/:id', async (req, res, next) => {
   if (!track) {
     track = await lastfm.getTrackMetaReal(id)
     if (!track) return next(new Error('404 file not found'))
+    if (dl) {
+      lastfm.invokeDownload(id)
+      return res.end('<p>OK</p><script>window.close();</script>')
+    }
     return ffmpeg(track.file)
       .audioCodec('libmp3lame')
       .format('mp3')