app.py

from flask import Flask, render_template, request, send_from_directory, abort, redirect
import os
from pytube import YouTube, Playlist
import ffmpeg
import eyed3
from werkzeug.datastructures import FileStorage
from moviepy.editor import VideoFileClip
from pytube.helpers import safe_filename
import shutil

#file pathname separator
sep = os.sep

UPLOAD_FOLDER = '.' + sep + 'upload-files'
app = Flask(__name__)

app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER
app.config['CLIENT_FILES'] = os.getcwd()

#original app route to index page
@app.route('/')
def index():
    return render_template('index.html')


#template page after pressing mp3 option button 
@app.route('/mp3_option_button', methods = ["GET", "POST"])
def mp3_option_button():
    if request.method == "POST":
        return render_template('index.html', option_form_mp3 = "mp3")
    return render_template('index.html')

      
#template page after pressing mp4 option button
@app.route('/mp4_option_button', methods = ["GET", "POST"])
def mp4_option_button():
    if request.method == "POST":
        return render_template('index.html', option_form_mp4 = "mp4")
    return render_template('index.html')


#mp3 download function after link inserted and download mp3 button pressed
@app.route('/mp3_download', methods= ["GET", "POST"])
def mp3_download():
    if request.method == "POST":
        youtube_link = request.form.get("youtube_link")
        
        if "playlist" in youtube_link:
            p = Playlist(youtube_link)
            destination = safe_filename(p.title)
            os.mkdir(destination) # create playlist folder
            os.chdir(destination) # change working directory to inside of playlist folder

            for video in p.videos:
                out_file = video.streams.filter(only_audio=True).first().download() # download audio
                uselesspath, regFileName = os.path.split(out_file) # keep regularized filename because yt title can have illegal characters
                base, ext = os.path.splitext(out_file)
                new_file = base + '.mp3'
                os.system("ffmpeg -i " + '"' + regFileName + '" "' + new_file + '"') # mp4 to mp3
                os.remove(regFileName)
            os.chdir("..") # change working directory back to project folder

            shutil.make_archive(destination, 'zip', destination)       #make a zip folder of all mp3 songs to download it later as one file

            global finalFileNameMp3
            finalFileNameMp3 = destination + ".zip"   #save final playlist folder of mp3s, to download it later
            
            return render_template('index.html', result = "Download Complete", option_form_mp3 = "mp3", player_button_open = "open")
        else: # single video
            yt = YouTube(str(youtube_link))
  
            # extract only audio
            video = yt.streams.filter(only_audio=True).first()
            
            # check for destination to save file
            destination = '.'
            
            # download the file
            out_file = video.download(output_path=destination)

            # save the file
            uselesspath, regFileName = os.path.split(out_file) # keep regularized filename because yt title can have illegal characters
            base, ext = os.path.splitext(out_file)
            new_file = base + '.mp3'
            os.system("ffmpeg -i " + '"' + regFileName + '" "' + new_file + '"') # mp4 to mp3
            print(regFileName,"Hey!")
            os.remove(regFileName)

            global fileNameDownloadPath
            fileNameDownloadPath = new_file

            global songFileNameToTrimmer
            useless, songFileNameToTrimmer = fileNameDownloadPath.split(sep+'.'+sep)
            os.rename(songFileNameToTrimmer, "temp-download.mp3")
            os.system("ffmpeg -i temp-download.mp3 -ab 320k temp.mp3")
            os.rename("temp.mp3", songFileNameToTrimmer)
            os.remove("temp-download.mp3")
            return render_template('index.html', result = "Download Complete", option_form_mp3 = "mp3", trimmer_open = "open")
            

    return render_template('index.html')


#mp4 download function after link inserted
@app.route('/mp4_download', methods= ["GET", "POST"])
def mp4_download():
    youtube_link = request.form.get("youtube_link")
    video_quality = request.form.get("video_quality")

    global videoFileName
    if request.method == "POST":
        if "playlist" in youtube_link:
            p = Playlist(youtube_link)
            destination = safe_filename(p.title)
            os.mkdir(destination) # create playlist folder
            os.chdir(destination) # change working directory to inside of playlist folder
            for video in p.videos:
                # get the highest available quality not exceeding the chosen quality
                v_quality = video.streams.get_highest_resolution().resolution
                if int(v_quality.replace("p","")) > int(video_quality.replace("p","")): # keep the lowest of chosen and max quality
                    v_quality = video_quality
                fileNameDownloadPathVideoOnly = video.streams.filter(res = v_quality).first().download('.'+sep+'temp-video')
                #yt.streams.filter(progressive=True, file_extension='mp4').order_by('resolution').desc().first().download('.')
                
                useless, videoFileName = fileNameDownloadPathVideoOnly.split('.'+sep+'temp-video'+sep)   #keep the video file name for later in order to save it

                out_file = video.streams.filter(only_audio=True).first().download('.'+sep+'temp-audio')  #extract audio only
                
                # save the file
                base, ext = os.path.splitext(out_file)
                print(ext)
                new_file = base + '_audio.mp4'
                os.rename(out_file, new_file)

                fileNameDownloadPathAudioOnly = new_file

                video_stream = ffmpeg.input(fileNameDownloadPathVideoOnly)
                audio_stream = ffmpeg.input(fileNameDownloadPathAudioOnly)
                ffmpeg.output(audio_stream, video_stream, videoFileName).run()

                if os.path.exists(str(fileNameDownloadPathVideoOnly)) and os.path.exists(str(fileNameDownloadPathAudioOnly)):       #delete the temp video and audio files
                    os.remove(str(fileNameDownloadPathAudioOnly))
                    os.remove(str(fileNameDownloadPathVideoOnly))
                else:
                    print("The files do not exist")

            os.rmdir("temp-audio") # remove temp directories
            os.rmdir("temp-video")
            os.chdir("..") # change working directory back to project folder

            shutil.make_archive(destination, 'zip', destination)       #make a zip folder of all mp3 songs to download it later as one file

            videoFileName = destination + ".zip"   #save final playlist folder of mp3s, to download it later

            return render_template('index.html', result = "Download Complete", option_form_mp4 = "mp4", mp4_download_button_open = "open")
        else:
            yt = YouTube(str(youtube_link))
            # get the highest available quality not exceeding the chosen quality
            v_quality = yt.streams.get_highest_resolution().resolution
            if int(v_quality.replace("p","")) > int(video_quality.replace("p","")): # keep the lowest of chosen and max quality
                v_quality = video_quality
            fileNameDownloadPathVideoOnly = yt.streams.filter(res = v_quality).first().download('.'+sep+'temp-video')
            #yt.streams.filter(progressive=True, file_extension='mp4').order_by('resolution').desc().first().download('.')
            
            useless, videoFileName = fileNameDownloadPathVideoOnly.split('.'+sep+'temp-video'+sep)   #keep the video file name for later in order to save it

            out_file = yt.streams.filter(only_audio=True).first().download('.'+sep+'temp-audio')  #extract audio only
            
            # save the file
            base, ext = os.path.splitext(out_file)
            print(ext)
            new_file = base + '_audio.mp4'
            os.rename(out_file, new_file)

            fileNameDownloadPathAudioOnly = new_file

            video_stream = ffmpeg.input(fileNameDownloadPathVideoOnly)
            audio_stream = ffmpeg.input(fileNameDownloadPathAudioOnly)
            ffmpeg.output(audio_stream, video_stream, videoFileName).run()

            if os.path.exists(str(fileNameDownloadPathVideoOnly)) and os.path.exists(str(fileNameDownloadPathAudioOnly)):       #delete the temp video and audio files
                os.remove(str(fileNameDownloadPathAudioOnly))
                os.remove(str(fileNameDownloadPathVideoOnly))
            else:
                print("The files do not exist")

            os.rmdir("temp-audio") # remove temp directories
            os.rmdir("temp-video")

            return render_template('index.html', result = "Download Complete", option_form_mp4 = "mp4", mp4_trimmer_open = "open")
    
    return render_template('index.html')


#mp3 trimmer template after mp3 file download complete
@app.route('/trimmer_editor', methods = ["GET", "POST"])
def trimmer_editor():
    if request.method == "POST":

        start = str(request.form.get("start-time"))
        end = str(request.form.get("end-time"))

        global fileNameDownloadPath

        if start == '' and end == '':       #if no values for trim have been inserted, just default passthrough to trimmer library
            os.system("trimmer " + '"' + songFileNameToTrimmer + '"' + " --title tempTitle --artist tempArtist")
            fileNameDownloadPath = str("tempArtist - tempTitle.mp3")
            return render_template('index.html', result = "Download Complete", option_form_mp3 = "mp3", result_trimmer = "Default trim applied", metadata_editor_open = "open")
        elif start != '' and end == '':     #if only start value for trim has been inserted
            os.system("trimmer " + '"' + songFileNameToTrimmer + '"' + " --trim-start " + start + " --title tempTitle --artist tempArtist")
            fileNameDownloadPath = str("tempArtist - tempTitle.mp3")
            return render_template('index.html', result = "Download Complete", option_form_mp3 = "mp3", result_trimmer = "Trim for Start Done", metadata_editor_open = "open")
        elif start == '' and end != '':     #if only end value for trim has been inserted
            os.system("trimmer " + '"' + songFileNameToTrimmer + '"' + " --trim-end " + end + " --title tempTitle --artist tempArtist")
            fileNameDownloadPath = str("tempArtist - tempTitle.mp3")
            return render_template('index.html', result = "Download Complete", option_form_mp3 = "mp3", result_trimmer = "Trim for End Done", metadata_editor_open = "open")
        else:           #if both values have been inserted
            os.system("trimmer " + '"' + songFileNameToTrimmer + '"' + " --trim-start " + start + " --trim-end " + end + " --title tempTitle --artist tempArtist")
            fileNameDownloadPath = str("tempArtist - tempTitle.mp3")
            return render_template('index.html', result = "Download Complete", option_form_mp3 = "mp3", result_trimmer = "Trim Done", metadata_editor_open = "open")
    return render_template('index.html')


#mp4 trimmer template after mp4 file download complete
@app.route('/mp4_trimmer_editor', methods = ["GET", "POST"])
def mp4_trimmer_editor():
    if request.method == "POST":

        start = str(request.form.get("start-time"))
        end = str(request.form.get("end-time"))

        clip = VideoFileClip(videoFileName)
        duration = clip.duration

        global fileNameDownloadPath
        
        if start == '' and end == '':       #if no values for trim have been inserted, just default passthrough to trimmer library
            return render_template('index.html', result = "Download Complete", option_form_mp4 = "mp4", mp4_trimmer_open = "open", result_trimmer = "Trim not applied", mp4_download_button_open = "open")
        elif start != '' and end == '':     #if only start value for trim has been inserted
            os.system("ffmpeg -i " + '"' + videoFileName + '"' + " -codec copy " + '"' + "temp_vid.mp4" + '"')
            os.system("ffmpeg -y -i " + '"' + "temp_vid.mp4" + '"' + " -ss " + start + " -to " + str(duration) + " -c:v copy -c:a copy " + '"' + videoFileName + '"')
            os.remove("temp_vid.mp4")
            return render_template('index.html', result = "Download Complete", option_form_mp4 = "mp4", mp4_trimmer_open = "open", result_trimmer = "Trim for Start Done", mp4_download_button_open = "open")
        elif start == '' and end != '':     #if only end value for trim has been inserted
            os.system("ffmpeg -i " + '"' + videoFileName + '"' + " -codec copy " + '"' + "temp_vid.mp4" + '"')
            os.system("ffmpeg -y -i " + '"' + "temp_vid.mp4" + '"' + " -ss " + "0" + " -to " + str(duration - int(end)) + " -c:v copy -c:a copy " + '"' + videoFileName + '"')
            os.remove("temp_vid.mp4")
            return render_template('index.html', result = "Download Complete", option_form_mp4 = "mp4", mp4_trimmer_open = "open", result_trimmer = "Trim for End Done", mp4_download_button_open = "open")
        else:           #if both values have been inserted
            os.system("ffmpeg -i " + '"' + videoFileName + '"' + " -codec copy " + '"' + "temp_vid.mp4" + '"')
            os.system("ffmpeg -y -i " + '"' + "temp_vid.mp4" + '"' + " -ss " + start + " -to " + str(duration - int(end)) + " -c:v copy -c:a copy " + '"' + videoFileName + '"')
            os.remove("temp_vid.mp4")

            return render_template('index.html', result = "Download Complete", option_form_mp4 = "mp4", result_trimmer = "Trim Done", mp4_download_button_open = "open")

    return render_template('index.html')


#mp3 metadata editor after mp3 file trimming complete
@app.route('/mp3_metadata_editor', methods= ["GET", "POST"])
def mp3_metadata_editor():
    if request.method == "POST":

        in_artist = str(request.form.get("artist"))
        in_title = str(request.form.get("title"))

        if (in_artist!="tempArtist"):
            artist = in_artist
        else:
            artist = ''
        album = str(request.form.get("album"))
        album_artist = str(request.form.get("album_artist"))
        if (in_title!="tempTitle"):
            title = in_title
        else:
            title=''
        track_number = str(request.form.get("track_number"))
        genre = str(request.form.get("genre"))
        year = str(request.form.get("year"))
        cover_art_file = request.files['cover_art_file']
        
        flag_no_cover_user = False
        if cover_art_file.filename == '':   #here we check if the request includes a cover art file
            flag_no_cover_user = True
            with open('.'+sep+'default-cover.jpeg', "rb") as fp:
                cover_art_file = FileStorage(fp, content_type='image/jpeg')
        else:
            cover_art_file.save(os.path.join(app.config['UPLOAD_FOLDER'], cover_art_file.filename))


        songFileName = fileNameDownloadPath

        os.rename(songFileName, "temp.mp3")
        os.system("ffmpeg -i temp.mp3 -ab 320k temp2.mp3")
        os.rename("temp2.mp3", songFileName)
        os.remove("temp.mp3")

        try:
            audioFile = eyed3.load(songFileName)
            if not audioFile.tag:
                audioFile.initTag()

            if audioFile:
                audioFile.tag.artist = artist
                audioFile.tag.album = album
                audioFile.tag.album_artist = album_artist
                audioFile.tag.title = title
                audioFile.tag.track_number = track_number
                audioFile.tag.genre = genre
                audioFile.tag.year = year

                if(flag_no_cover_user):
                    with open(cover_art_file.filename, "rb") as cover_art:
                        audioFile.tag.images.set(0, cover_art.read(), "image/jpeg")

                    with open(cover_art_file.filename, "rb") as cover_art:
                        audioFile.tag.images.set(3, cover_art.read(), "image/jpeg")
                else:
                    with open(UPLOAD_FOLDER + sep + cover_art_file.filename, "rb") as cover_art:
                        audioFile.tag.images.set(0, cover_art.read(), "image/jpeg")

                    with open(UPLOAD_FOLDER + sep + cover_art_file.filename, "rb") as cover_art:
                        audioFile.tag.images.set(3, cover_art.read(), "image/jpeg")

                audioFile.tag.save()

                global finalFileNameMp3

                if (artist=='' or title==''):
                    finalFileNameMp3 = songFileNameToTrimmer
                else:
                    finalFileNameMp3 = artist + " - " + title + ".mp3"
                os.rename(songFileName, finalFileNameMp3)

                if(flag_no_cover_user == False):
                    os.remove(app.config['UPLOAD_FOLDER']+ sep + cover_art_file.filename)


        except IOError:
            IOError
        
        return render_template('index.html', result = "Download Complete", option_form_mp3 = "mp3", player_button_open = "open")
    return render_template('index.html')

#render mp3 player page in browser
@app.route('/mp3_player', methods= ["GET", "POST"])
def mp3_player():
    return render_template('mp3-player-One.html')

@app.route('/mp4_player', methods=["GET", "POST"])
def mp4_player():
    return render_template('mp4-player.html')

#download the final music file to downloads folder in user's computer
@app.route('/download_file', methods = ["GET", "POST"])
def download_file():
    print(app.config['CLIENT_FILES'])
    print(finalFileNameMp3)
    try:
        return send_from_directory(directory = app.config['CLIENT_FILES'], path = finalFileNameMp3, as_attachment = True)
    except FileNotFoundError:
        abort(404)

#download the final video file to downloads folder in user's computer
@app.route('/download_mp4_file', methods = ["GET", "POST"])
def download_mp4_file():
    print(app.config['CLIENT_FILES'])
    print(videoFileName)
    try:
        return send_from_directory(directory = app.config['CLIENT_FILES'], path = videoFileName, as_attachment = True)
    except FileNotFoundError:
        abort(404)


if __name__ == "__main__":
    app.run(debug=True)