#!/usr/bin/env python3
# -*- coding: utf-8 -*-

##############################################################################
# Find gaps between MythTV recordings.
#
# Author: J S Worthington
##############################################################################

from __future__ import print_function

import argparse
import datetime
import dateutil.parser
import sys
from MythTV.services_api import send as api

py_version = '3'
if sys.version_info.major == 2:
    py_version = '2'

try:
    from MythTV import MythBE
except:
    print('Please install the MythTV Python ' + py_version + ' bindings')
    exit(2)

#try:
#    import Utilities as api
#except:
#    print('Please install the MythTV Utilities.py file - suggested location: /usr/local/bin.')
#    print('The Utilities.py file is available as text from here:')
#    print('  https://www.mythtv.org/wiki/Python_API_Examples')
#    print('Please ensure that it is saved in UTF-8 format.')
#    exit(2)

try:
    from enum import IntEnum
except:
    print('Please install the Python ' + py_version + ' enum34 package')
    exit(2)

try:
    import dateutil.parser
except:
    print('Please install the Python ' + py_version + ' dateutil package')
    exit(2)

"""
    Version 1.5:
        - Convert from Python 2 to Python 2 and Python 3 compatible.
        - Handle exception when unable to connect to mythbackend.  This used
          to return an "Error" value from "send", but now in MythTV v31 and
          Python 3 raises an exception.
    Version 1.5.1:

"""
VERSION = '1.5.1'

HOST = 'localhost'
PORT = 6544

class RecStatus(IntEnum):
    Pending = -15
    Failing = -14
    #OtherRecording = -13 (obsolete)
    #OtherTuning = -12 (obsolete)
    MissedFuture = -11
    Tuning = -10
    Failed = -9
    TunerBusy = -8
    LowDiskSpace = -7
    Cancelled = -6
    Missed = -5
    Aborted = -4
    Recorded = -3
    Recording = -2
    WillRecord = -1
    Unknown = 0
    DontRecord = 1
    PreviousRecording = 2
    CurrentRecording = 3
    EarlierShowing = 4
    TooManyRecordings = 5
    NotListed = 6
    Conflict = 7
    LaterShowing = 8
    Repeat = 9
    Inactive = 10
    NeverRecord = 11
    Offline = 12
    #OtherShowing = 13 (obsolete)

HERE = dateutil.tz.tzlocal()
UTC = dateutil.tz.gettz('UTC')


##############################################################################
# Round off the microseconds in a naive datetime and zero the microseconds
# field.
##############################################################################

def round_to_s(dt):
    microseconds = dt.microsecond
    if microseconds >= 500000:
        dt += datetime.timedelta(0, 0, 1000000-microseconds)
    else:
        dt -= datetime.timedelta(0, 0, microseconds)
    return dt


##############################################################################
# Convert an aware UTC datetime to a naive UTC datetime.
##############################################################################

def naive(dt):
    return dt.astimezone(dateutil.tz.tzutc()).replace(tzinfo=None)


##############################################################################
# Convert a naive UTC datetime to an aware local datetime.
##############################################################################

def utc_to_local(dt):
    return dt.replace(tzinfo=UTC).astimezone(HERE)


##############################################################################
# Main
##############################################################################


host = HOST
port = PORT

try:
    mythtv_bindings_ok = True
    import MythTV
except:
    mythtv_bindings_ok = False
    print('Unable to load MythTV Python bindings, and hence unable to read config.xml.  Using default settings.')

if mythtv_bindings_ok:
    try:
        db = MythTV.MythDB()
        dbc = db.cursor()
        rows = dbc.execute("select data,hostname from settings where value='BackendStatusPort'")
        if rows == 0:
            print('MythTV database does not have BackendStatusPort settings, using defaults')
        else:
            row = dbc.fetchone()
            port = int(row[0])
            host = row[1]
    except:
        print('Unable to get BackendStatusPort settings from MythTV database, using defaults')

#print('host='+host, 'port='+str(port))

parser = argparse.ArgumentParser(
    description='Find gaps in the MythTV recording schedule (Version: ' + VERSION + ')',
    formatter_class=lambda prog: argparse.HelpFormatter(prog, max_help_position=15)
    )
parser.add_argument('-V', '--version', dest='version', default=False, action='store_true',
    help='display the version number and exit')
parser.add_argument('-n', '--host', action='store', help='MythTV backend hostname (default: '+host+')')
parser.add_argument('-p', '--port', type=int, action='store', help='MythTV backend API port number (default: '+str(port)+')')
parser.add_argument('hours', type=float, nargs='?', default=0.0, help='Minimum gap duration to search for, in hours (floating point allowed)')
parser.add_argument('minutes', type=float, nargs='?', default=0.0, help='Minimum gap duration to search for, in minutes (floating point allowed)')
args = parser.parse_args()
if args.version:
    print('Version '+VERSION)
    exit(1)
if args.port != None:
    port = args.port
if args.host != None:
    host = args.host
min_duration = datetime.timedelta(0, 0, 0, 0, args.minutes, args.hours)

if min_duration != datetime.timedelta(0):
    print('Searching for a minimum duration of '+str(min_duration))

backend = api.Send(host=host, port=port)
try:
    resp_dict = backend.send(endpoint='Dvr/GetUpcomingList')
except RuntimeError:
    print('Connection to backend failed - is mythbackend running?')
    exit(2)

if list(resp_dict.keys())[0] in ['Abort', 'Warning']:
    print('GetUpcomingList failed')
    exit(2)

pending = resp_dict['ProgramList']['Programs']
# pending is in StartTs order.  The following code relies on this.
pending_count = int(resp_dict['ProgramList']['Count'])

if pending_count == 0:
    print('No recordings scheduled!')
    exit(0)

furthest_end = round_to_s(datetime.datetime.utcnow())
#print('furthest_end='+str(utc_to_local(furthest_end)))

i = 0
recording = pending[i]['Recording']
while int(recording['Status']) == RecStatus.Recording:
    endts = naive(dateutil.parser.parse(recording['EndTs']))
    #print('1 endts='+str(utc_to_local(endts)))
    if endts > furthest_end:
        furthest_end = endts;
        #print('1 furthest_end='+str(utc_to_local(furthest_end)))
    i += 1
    if i >= pending_count:
        break
    recording = pending[i]['Recording']
    #print("1 recording['Status']="+recording['Status'])

while i < pending_count:
    while i < pending_count:
        if int(recording['Status']) == RecStatus.WillRecord:
            willrecord = 'WillRecord'
        else:
            willrecord=''
        startts = naive(dateutil.parser.parse(recording['StartTs']))
        #print("2 startts="+str(utc_to_local(startts)), willrecord)
        if int(recording['Status']) == RecStatus.WillRecord:
            if naive(dateutil.parser.parse(recording['StartTs'])) > furthest_end:
                break
            endts = naive(dateutil.parser.parse(recording['EndTs']))
            #print('  2 endts='+str(utc_to_local(endts)))
            if endts > furthest_end:
                furthest_end = endts
                #print('  2 furthest_end='+str(utc_to_local(furthest_end)))
        i += 1
        if i >= pending_count:
            break
        recording = pending[i]['Recording']
    if i >= pending_count:
        break
    endts = naive(dateutil.parser.parse(recording['EndTs']))
    duration = startts - furthest_end
    if duration >= min_duration:
        local_furthest_end = utc_to_local(furthest_end)
        print('Gap:  start='+local_furthest_end.strftime("%a")+' '+str(local_furthest_end)+'  end='+str(utc_to_local(startts))+'  duration='+str(duration))
    furthest_end = endts

print('End of scheduled recordings                end='+str(utc_to_local(furthest_end)))
exit(0)

# Example of the dictionary data returned by Dvr/GetUpcomingList API call via Utilities.py:
#{u'Category': u'Education/Science/Factual', u'SubProps': u'0', u'CatType': u'series', u'Title': u'24 Hours In A&E', u'LastModified': u'2017-04-18T14:39:29Z', u'Stars': u'0', u'Episode': u'0', u'EndTime': u'2017-04-18T19:25:00Z', u'Channel': {u'Programs': [], u'ChanFilters': u'', u'UseEIT': u'false', u'Visible': u'true', u'IconURL': u'', u'SourceId': u'6', u'FineTune': u'0', u'Format': u'Default', u'ATSCMajorChan': u'0', u'MplexId': u'0', u'ChanNum': u'4074', u'ChanId': u'10074', u'CommFree': u'false', u'CallSign': u'KNOWLGE', u'InputId': u'0', u'DefaultAuth': u'', u'ServiceId': u'1059', u'FrequencyId': u'', u'ChannelName': u'BBC Knowledge', u'ATSCMinorChan': u'0', u'XMLTVID': u'documentary.sky.co.nz'}, u'SeriesId': u'1490837', u'Repeat': u'false', u'Description': u'54-year-old epileptic Mike arrives in minors with a bandage round his jaw after falling face first onto a pavement.', u'Season': u'0', u'HostName': u'mypvr', u'ProgramFlags': u'0', u'SubTitle': u'Always On My Mind', u'VideoProps': u'0', u'TotalEpisodes': u'0', u'Artwork': {u'ArtworkInfos': []}, u'Recording': {u'Status': u'-1', u'RecordedId': u'0', u'EncoderName': u'SAT>IP 1.1 (90)', u'RecGroup': u'CRW and JSW', u'DupMethod': u'8', u'RecordId': u'11099', u'LastModified': u'2017-04-18T14:39:29Z', u'HostName': u'mypvr', u'StartTs': u'2017-04-18T18:35:00Z', u'FileName': u'', u'Priority': u'0', u'EncoderId': u'90', u'Profile': u'Default', u'StorageGroup': u'Default', u'EndTs': u'2017-04-18T19:30:00Z', u'DupInType': u'15', u'RecType': u'4', u'PlayGroup': u'Default', u'FileSize': u'0'}, u'Cast': {u'CastMembers': []}, u'Inetref': u'', u'Airdate': u'', u'AudioProps': u'0', u'FileName': u'', u'ProgramId': u'', u'FileSize': u'0', u'StartTime': u'2017-04-18T18:35:00Z'}