from PySide2 import QtCore, QtGui
from PySide2.QtCore import Signal, Slot
from PIL import Image, ImageDraw, ImageFont
from PIL.ImageQt import ImageQt
import core
import numpy
import subprocess as sp
import sys

class Worker(QtCore.QObject):

  videoCreated = Signal()
  progressBarUpdate = Signal(int)
  progressBarSetText = Signal(str)

  def __init__(self, parent=None):
    QtCore.QObject.__init__(self)
    parent.videoTask.connect(self.createVideo)
    self.core = core.Core()


  @Slot(str, str, QtGui.QFont, int, int, int, int, tuple, tuple, str, str)
  def createVideo(self, backgroundImage, titleText, titleFont, fontSize, alignment,\
                    xOffset, yOffset,  textColor, visColor, inputFile, outputFile):
    # print('worker thread id: {}'.format(QtCore.QThread.currentThreadId()))
    def getBackgroundAtIndex(i):
        return self.core.drawBaseImage(
            backgroundFrames[i],
            titleText,
            titleFont,
            fontSize,
            alignment,
            xOffset,
            yOffset,
            textColor,
            visColor)

    progressBarValue = 0
    self.progressBarUpdate.emit(progressBarValue)
    self.progressBarSetText.emit('Loading background image…')

    backgroundFrames = self.core.parseBaseImage(backgroundImage)
    if len(backgroundFrames) < 2:
        # the base image is not a video so we can draw it now
        imBackground = getBackgroundAtIndex(0)
    else:
        # base images will be drawn while drawing the audio bars
        imBackground = None
        
    self.progressBarSetText.emit('Loading audio file…')
    completeAudioArray = self.core.readAudioFile(inputFile)

    # test if user has libfdk_aac
    encoders = sp.check_output(self.core.FFMPEG_BIN + " -encoders -hide_banner", shell=True)
    if b'libfdk_aac' in encoders:
      acodec = 'libfdk_aac'
    else:
      acodec = 'aac'

    ffmpegCommand = [ self.core.FFMPEG_BIN,
       '-y', # (optional) means overwrite the output file if it already exists.
       '-f', 'rawvideo',
       '-vcodec', 'rawvideo',
       '-s', '1280x720', # size of one frame
       '-pix_fmt', 'rgb24',
       '-r', '30', # frames per second
       '-i', '-', # The input comes from a pipe
       '-i', inputFile,
       '-acodec', acodec, # output audio codec
       '-b:a', "192k",
       '-vcodec', "libx264",
       '-pix_fmt', "yuv420p",
       '-preset', "medium",
       '-f', "mp4"]

    if acodec == 'aac':
      ffmpegCommand.append('-strict')
      ffmpegCommand.append('-2')

    ffmpegCommand.append(outputFile)
    
    out_pipe = sp.Popen(ffmpegCommand,
        stdin=sp.PIPE,stdout=sys.stdout, stderr=sys.stdout)

    smoothConstantDown = 0.08
    smoothConstantUp = 0.8
    lastSpectrum = None
    sampleSize = 1470
    
    numpy.seterr(divide='ignore')
    bgI = 0
    for i in range(0, len(completeAudioArray), sampleSize):
      # create video for output
      lastSpectrum = self.core.transformData(
        i,
        completeAudioArray,
        sampleSize,
        smoothConstantDown,
        smoothConstantUp,
        lastSpectrum)
      if imBackground != None:
        im = self.core.drawBars(lastSpectrum, imBackground, visColor)
      else:
        im = self.core.drawBars(lastSpectrum, getBackgroundAtIndex(bgI), visColor)
        if bgI < len(backgroundFrames)-1:
            bgI += 1

      # write to out_pipe
      try:
        out_pipe.stdin.write(im.tobytes())
      finally:
        True

      # increase progress bar value
      if progressBarValue + 1 <= (i / len(completeAudioArray)) * 100:
        progressBarValue = numpy.floor((i / len(completeAudioArray)) * 100)
        self.progressBarUpdate.emit(progressBarValue)
        self.progressBarSetText.emit('%s%%' % str(int(progressBarValue)))

    numpy.seterr(all='print')

    out_pipe.stdin.close()
    if out_pipe.stderr is not None:
      print(out_pipe.stderr.read())
      out_pipe.stderr.close()
    # out_pipe.terminate() # don't terminate ffmpeg too early
    out_pipe.wait()
    print("Video file created")
    self.core.deleteTempDir()
    self.progressBarUpdate.emit(100)
    self.progressBarSetText.emit('100%')
    self.videoCreated.emit()