#!/usr/bin/env python3
"""
"""

__author__ = "Nikola Kotur"
__version__ = "1.0"
__license__ = "Apache License 2.0"

import os
import sys
import argparse
import threading
import tempfile
import subprocess
import time
from multiprocessing import Queue
from pprint import pprint as pp

import pyudev
from logzero import logger


class FakeDev():
    device_node = '/dev/fake'
    device_type = 'dummy'


class USBDetector():
    def __init__(self, handler, config):
        self.usb_plugged_in = handler
        self.config = config

    def run(self):
        thread = threading.Thread(target=self._work)
        thread.daemon = True
        thread.start()
        thread.join()

    def _work(self):
        if self.config.dry_run:
            self.usb_plugged_in(FakeDev(), self.config)
            return
        self.context = pyudev.Context()
        self.monitor = pyudev.Monitor.from_netlink(self.context)
        self.monitor.filter_by(subsystem='block')
        logger.info("Starting to monitor for usb")
        self.monitor.start()
        for device in iter(self.monitor.poll, None):
            logger.debug("Got USB event: %s", device.action)
            if device.action == 'add' and device.device_type == 'partition':
                self.usb_plugged_in(device, self.config)


def execute(shell_command):
    shell_command = shell_command.split(' ')
    try:
        res = subprocess.check_output(shell_command, stderr=subprocess.PIPE)
        return res.decode('utf-8')
    except subprocess.CalledProcessError as e:
        print('exit code: {}'.format(e.returncode))
        print('stdout: {}'.format(e.output.decode(sys.getfilesystemencoding())))
        print('stderr: {}'.format(e.stderr.decode(sys.getfilesystemencoding())))
        return None


def group_name(full_path):
    return os.path.basename(full_path).split('.')[0]


def parse_video_files(usb_dir, base_dir, extension):
    files = {}
    for file in os.listdir(os.path.join(usb_dir, base_dir)):
        if file.endswith(extension):
            full_path = (os.path.join(usb_dir, base_dir, file))
            file_parts = file.split('_')
            part_date = file_parts[0]
            # Detect newer VIOFO
            if len(part_date) == 14:
                # Newer VIOFO, just take the date part
                part_date = part_date[0:8]
            if part_date not in files:
                files[part_date] = []
            files[part_date].append(full_path)
    return files


def join_video_files(dest, sources):
    with tempfile.TemporaryDirectory() as tmpdirname:
        list_file = os.path.join(tmpdirname, 'list')
        with open(list_file, 'w') as lfh:
            for source_line in sources:
                lfh.write("file '%s'\n" % source_line)

        ffmpeg_line = 'ffmpeg -safe 0 -f concat -i %s -c copy %s' % (list_file, dest)
        output = execute(ffmpeg_line)
    if output != None:
        logger.info(f'{group_name(dest)}: removing source files...')
        for s_file in sources:
            os.remove(s_file)
        logger.info(f'{group_name(dest)}: removed source files')
        return True
    return False


def encoder(q, config, file_groups):
    for file_group, files in file_groups:
        logger.info(f"{file_group}: joining...")
        outfile_name = '%s.mp4' % file_group
        outfile_path = os.path.join(config.destination, outfile_name)
        if join_video_files(outfile_path, files):
            logger.info(f"{file_group}: joined")
            q.put(outfile_path)
    q.put(None)


def uploader(q, config):
    while True:
        file_group = q.get()
        if file_group is None:
            break
        logger.info(f"{group_name(file_group)}: uploading...")
        output = execute('ncftpput -u %s -p %s %s %s %s' % (config.ftp_user, config.ftp_password, config.ftp_host, config.ftp_path, file_group))
        if output != None:
            logger.info(f"{group_name(file_group)}: uploaded")
            logger.info(f"{group_name(file_group)}: removing...")
            os.remove(file_group)
            logger.info(f"{group_name(file_group)}: removed")


def plugged_in(dev, config):
    logger.info('Detected %s (%s)', dev.device_node, dev.device_type)
    with tempfile.TemporaryDirectory() as tmpdirname:
        logger.info('Mounting %s on %s', dev.device_node, tmpdirname)
        if not config.dry_run:
            output = execute('mount %s %s' % (dev.device_node, tmpdirname))

        q = Queue()
        t1 = threading.Thread(target=lambda: encoder(q, config, parse_video_files(tmpdirname, config.source, 'MP4').items()))
        t2 = threading.Thread(target=lambda: uploader(q, config))
        t1.start()
        t2.start()
        t1.join()

        logger.info('Umounting %s from %s', dev.device_node, tmpdirname)
        if not config.dry_run:
            output = execute('umount %s' % (dev.device_node))
        t2.join()

    logger.info('Done')


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument("--dry-run", help="fake everything, really do nothing", action="store_true", default=False)
    parser.add_argument("-s", "--source", help="source directory with dashcam videos", action="store", dest="source", default="DCIM/Movie")
    parser.add_argument("-d", "--destination", help="destination directory for joined dashcam videos", action="store", dest="destination", default="/var/dashcam")
    parser.add_argument("--ftp-host", help="ftp host (server)", action="store", default="192.168.88.242")
    parser.add_argument("--ftp-path", help="ftp path", action="store", default="/dashcam")
    parser.add_argument("--ftp-user", help="ftp user", action="store", default="dashcam")
    parser.add_argument("--ftp-password", help="ftp user", action="store", default="")
    parser.add_argument("--version", action="version", version="%(prog)s (version {version})".format(version=__version__))
    parser.add_argument("--test-grouping", help="just test grouping of videos", action="store_true", default=False)
    options = parser.parse_args()
    if options.test_grouping:
        pp(parse_video_files(options.source, '', 'MP4'))
        sys.exit(0)
    monitor = USBDetector(plugged_in, options)
    monitor.run()