import sys
import io
import os
from PyQt4 import QtCore, QtGui, uic
from os.path import expanduser
import subprocess as sp
import numpy
from PIL import Image
from shutil import rmtree
import time
from collections import OrderedDict
import json
from importlib import import_module
from PyQt4.QtGui import QDesktopServices
import string


class Core():

    def __init__(self):
        self.FFMPEG_BIN = self.findFfmpeg()
        self.dataDir = QDesktopServices.storageLocation(
            QDesktopServices.DataLocation)
        self.presetDir = os.path.join(self.dataDir, 'presets')
        self.wd = os.path.dirname(os.path.realpath(__file__))
        self.loadEncoderOptions()
        self.videoFormats = Core.appendUppercase([
            '*.mp4',
            '*.mov',
            '*.mkv',
            '*.avi',
            '*.webm',
            '*.flv',
        ])
        self.audioFormats = Core.appendUppercase([
            '*.mp3',
            '*.wav',
            '*.ogg',
            '*.fla',
            '*.aac',
        ])
        self.imageFormats = Core.appendUppercase([
            '*.png',
            '*.jpg',
            '*.tif',
            '*.tiff',
            '*.gif',
            '*.bmp',
            '*.ico',
            '*.xbm',
            '*.xpm',
        ])

        self.findComponents()
        self.selectedComponents = []
        # copies of named presets to detect modification
        self.savedPresets = {}

    def findComponents(self):
        def findComponents():
            srcPath = os.path.join(self.wd, 'components')
            if os.path.exists(srcPath):
                for f in sorted(os.listdir(srcPath)):
                    name, ext = os.path.splitext(f)
                    if name.startswith("__"):
                        continue
                    elif ext == '.py':
                        yield name
        self.modules = [
            import_module('components.%s' % name)
            for name in findComponents()
        ]
        self.moduleIndexes = [i for i in range(len(self.modules))]

    def componentListChanged(self):
        for i, component in enumerate(self.selectedComponents):
            component.compPos = i

    def insertComponent(self, compPos, moduleIndex):
        if compPos < 0:
            compPos = len(self.selectedComponents) -1
        if len(self.selectedComponents) > 50:
            return None

        component = self.modules[moduleIndex].Component(
            moduleIndex, compPos)
        self.selectedComponents.insert(
            compPos,
            component)

        self.componentListChanged()
        return compPos

    def moveComponent(self, startI, endI):
        comp = self.selectedComponents.pop(startI)
        self.selectedComponents.insert(endI, comp)

        self.componentListChanged()
        return endI

    def removeComponent(self, i):
        self.selectedComponents.pop(i)
        self.componentListChanged()

    def clearComponents(self):
        self.selectedComponents = list()
        self.componentListChanged()

    def updateComponent(self, i):
        # print('updating %s' % self.selectedComponents[i])
        self.selectedComponents[i].update()

    def moduleIndexFor(self, compName):
        compNames = [mod.Component.__doc__ for mod in self.modules]
        index = compNames.index(compName)
        return self.moduleIndexes[index]

    def clearPreset(self, compIndex, loader=None):
        '''Clears a preset from a component'''
        self.selectedComponents[compIndex].currentPreset = None
        if loader:
            loader.updateComponentTitle(compIndex)

    def openPreset(self, filepath, compIndex, presetName):
        '''Applies a preset to a specific component'''
        saveValueStore = self.getPreset(filepath)
        if not saveValueStore:
            return False
        try:
            self.selectedComponents[compIndex].loadPreset(
                saveValueStore,
                presetName
            )
        except KeyError as e:
            print('preset missing value: %s' % e)

        self.savedPresets[presetName] = dict(saveValueStore)
        return True

    def getPreset(self, filepath):
        '''Returns the preset dict stored at this filepath'''
        if not os.path.exists(filepath):
            return False
        with open(filepath, 'r') as f:
            for line in f:
                saveValueStore = Core.presetFromString(line.strip())
                break
        return saveValueStore

    def openProject(self, loader, filepath):
        '''loader is the object calling this method (mainwindow/command)
        which implements an insertComponent method'''
        errcode, data = self.parseAvFile(filepath)
        if errcode == 0:
            try:
                for i, tup in enumerate(data['Components']):
                    name, vers, preset = tup
                    clearThis = False

                    # add loaded named presets to savedPresets dict
                    if 'preset' in preset and preset['preset'] != None:
                        nam = preset['preset']
                        filepath2 = os.path.join(
                            self.presetDir, name, str(vers), nam)
                        origSaveValueStore = self.getPreset(filepath2)
                        if origSaveValueStore:
                            self.savedPresets[nam] = dict(origSaveValueStore)
                        else:
                            # saved preset was renamed or deleted
                            clearThis = True

                    # insert component into the loader
                    i = loader.insertComponent(
                        self.moduleIndexFor(name), -1)
                    if i == None:
                        break

                    try:
                        if 'preset' in preset and preset['preset'] != None:
                            self.selectedComponents[i].loadPreset(
                                preset
                            )
                        else:
                            self.selectedComponents[i].loadPreset(
                                preset,
                                preset['preset']
                            )
                    except KeyError as e:
                        print('%s missing value %s' %
                            (self.selectedComponents[i], e))

                    if clearThis:
                        self.clearPreset(i, loader)
            except:
                errcode = 1
                data = sys.exc_info()


        if errcode == 1:
            typ, value, _ = data
            if typ.__name__ == KeyError:
                # probably just an old version, still loadable
                print('file missing value: %s' % value)
                return
            loader.createNewProject()
            msg = '%s: %s' % (typ.__name__, value)
            loader.showMessage(
                msg="Project file '%s' is corrupted." % filepath,
                showCancel=False,
                icon=QtGui.QMessageBox.Warning,
                detail=msg)

    def parseAvFile(self, filepath):
        '''Parses an avp (project) or avl (preset package) file.
        Returns data usable by another method.'''
        data = {}
        try:
            with open(filepath, 'r') as f:
                def parseLine(line):
                    '''Decides if a given avp or avl line is a section header'''
                    validSections = ('Components')
                    line = line.strip()
                    newSection = ''

                    if line.startswith('[') and line.endswith(']') \
                            and line[1:-1] in validSections:
                        newSection = line[1:-1]

                    return line, newSection

                section = ''
                i = 0
                for line in f:
                    line, newSection = parseLine(line)
                    if newSection:
                        section = str(newSection)
                        data[section] = []
                        continue
                    if line and section == 'Components':
                        if i == 0:
                            lastCompName = str(line)
                            i += 1
                        elif i == 1:
                            lastCompVers = str(line)
                            i += 1
                        elif i == 2:
                            lastCompPreset = Core.presetFromString(line)
                            data[section].append(
                                (lastCompName,
                                lastCompVers,
                                lastCompPreset)
                            )
                            i = 0
            return 0, data
        except:
            return 1, sys.exc_info()

    def importPreset(self, filepath):
        errcode, data = self.parseAvFile(filepath)
        returnList = []
        if errcode == 0:
            name, vers, preset = data['Components'][0]
            presetName = preset['preset'] \
                if preset['preset'] else os.path.basename(filepath)[:-4]
            newPath = os.path.join(
                self.presetDir,
                name,
                vers,
                presetName
            )
            if os.path.exists(newPath):
                return False, newPath
            preset['preset'] = presetName
            self.createPresetFile(
                name, vers, presetName, preset
            )
            return True, presetName
        elif errcode == 1:
            # TODO: an error message
            return False, ''

    def exportPreset(self, exportPath, compName, vers, origName):
        internalPath = os.path.join(self.presetDir, compName, str(vers), origName)
        if not os.path.exists(internalPath):
            return
        if os.path.exists(exportPath):
            os.remove(exportPath)
        with open(internalPath, 'r') as f:
            internalData = [line for line in f]
        try:
            saveValueStore = Core.presetFromString(internalData[0].strip())
            self.createPresetFile(
                compName, vers,
                origName, saveValueStore,
                exportPath
            )
            return True
        except:
            return False

    def createPresetFile(
        self, compName, vers, presetName, saveValueStore, filepath=''):
        '''Create a preset file (.avl) at filepath using args.
           Or if filepath is empty, create an internal preset using
           the args for the filepath.'''
        if not filepath:
            dirname = os.path.join(self.presetDir, compName, str(vers))
            if not os.path.exists(dirname):
                os.makedirs(dirname)
            filepath = os.path.join(dirname, presetName)
            internal = True
        else:
            if not filepath.endswith('.avl'):
                filepath += '.avl'
            internal = False

        with open(filepath, 'w') as f:
            if not internal:
                f.write('[Components]\n')
                f.write('%s\n' % compName)
                f.write('%s\n' % str(vers))
            f.write(Core.presetToString(saveValueStore))

    def createProjectFile(self, filepath):
        '''Create a project file (.avp) using the current program state'''
        try:
            if not filepath.endswith(".avp"):
                filepath += '.avp'
            if os.path.exists(filepath):
                os.remove(filepath)
            with open(filepath, 'w') as f:
                print('creating %s' % filepath)
                f.write('[Components]\n')
                for comp in self.selectedComponents:
                    saveValueStore = comp.savePreset()
                    f.write('%s\n' % str(comp))
                    f.write('%s\n' % str(comp.version()))
                    f.write('%s\n' % Core.presetToString(saveValueStore))
            return True
        except:
            return False

    def loadEncoderOptions(self):
        file_path = os.path.join(self.wd, 'encoder-options.json')
        with open(file_path) as json_file:
            self.encoder_options = json.load(json_file)

    def findFfmpeg(self):
        if sys.platform == "win32":
            return "ffmpeg.exe"
        else:
            try:
                with open(os.devnull, "w") as f:
                    sp.check_call(['ffmpeg', '-version'], stdout=f, stderr=f)
                return "ffmpeg"
            except:
                return "avconv"

    def readAudioFile(self, filename, parent):
        command = [self.FFMPEG_BIN, '-i', filename]

        try:
            fileInfo = sp.check_output(command, stderr=sp.STDOUT, shell=False)
        except sp.CalledProcessError as ex:
            fileInfo = ex.output
            pass

        info = fileInfo.decode("utf-8").split('\n')
        for line in info:
            if 'Duration' in line:
                d = line.split(',')[0]
                d = d.split(' ')[3]
                d = d.split(':')
                duration = float(d[0])*3600 + float(d[1])*60 + float(d[2])

        command = [
            self.FFMPEG_BIN,
            '-i', filename,
            '-f', 's16le',
            '-acodec', 'pcm_s16le',
            '-ar', '44100',  # ouput will have 44100 Hz
            '-ac', '1',  # mono (set to '2' for stereo)
            '-']
        in_pipe = sp.Popen(
            command, stdout=sp.PIPE, stderr=sp.DEVNULL, bufsize=10**8)

        completeAudioArray = numpy.empty(0, dtype="int16")

        progress = 0
        lastPercent = None
        while True:
            if self.canceled:
                break
            # read 2 seconds of audio
            progress = progress + 4
            raw_audio = in_pipe.stdout.read(88200*4)
            if len(raw_audio) == 0:
                break
            audio_array = numpy.fromstring(raw_audio, dtype="int16")
            completeAudioArray = numpy.append(completeAudioArray, audio_array)

            percent = int(100*(progress/duration))
            if percent >= 100:
                percent = 100

            if lastPercent != percent:
                string = 'Loading audio file: '+str(percent)+'%'
                parent.progressBarSetText.emit(string)
                parent.progressBarUpdate.emit(percent)

            lastPercent = percent

        in_pipe.kill()
        in_pipe.wait()

        # add 0s the end
        completeAudioArrayCopy = numpy.zeros(
            len(completeAudioArray) + 44100, dtype="int16")
        completeAudioArrayCopy[:len(completeAudioArray)] = completeAudioArray
        completeAudioArray = completeAudioArrayCopy

        return completeAudioArray

    def cancel(self):
        self.canceled = True

    def reset(self):
        self.canceled = False

    @staticmethod
    def badName(name):
        '''Returns whether a name contains non-alphanumeric chars'''
        return any([letter in string.punctuation for letter in name])

    @staticmethod
    def presetToString(dictionary):
        '''Alphabetizes a dict into OrderedDict & returns string repr'''
        return repr(OrderedDict(sorted(dictionary.items(), key=lambda t: t[0])))

    @staticmethod
    def presetFromString(string):
        '''Turns a string repr of OrderedDict into a regular dict'''
        return dict(eval(string))

    @staticmethod
    def appendUppercase(lst):
        for form, i in zip(lst, range(len(lst))):
            lst.append(form.upper())
        return lst