#!/usr/bin/env python3

"""
Enrich videobot’s europarl streamdumps with metadata from europarltv, including
topic, speaker and timestamps.

Expects a config file videobot_enricheuroparl.ini in the working directory.

TODO:
Additional speaker info: http://www.europarl.europa.eu/ep-live/en/speaker/1911?date=27-04-2016
"""


import json, math
from datetime import datetime, timedelta
from pytz import timezone
from dateutil.parser import parse
import requests

brussels = timezone('Europe/Brussels')

def fromTimestamp (ts):
    """
    Convert timestamp to datetime. Dates are local time (i.e. utc+1) and in
    milliseconds.
    """
    return datetime.fromtimestamp (ts/1000, tz=brussels)

def overlap (a, b):
    """
    Do intervals (a0, a1) and (b0, b1) overlap?
    """
    def contains (a, b):
        return a[0] <= b[0] <= a[1] or a[0] <= b[1] <= a[1]
    return contains (a, b) or contains (b, a)

def convertTimestamps (event):
    """
    Convert timestamps to datetime
    """
    chapters = event['chapters']
    for c in chapters:
        c['startTimeCode'] = fromTimestamp (c['startTimeCode'])
        c['endTimeCode'] = fromTimestamp (c['endTimeCode'])

        for s in c['speeches']:
            s['startTimeCode'] = fromTimestamp (s['startTimeCode'])
            s['endTimeCode'] = fromTimestamp (s['endTimeCode'])
    return event

def filterRecording (event, recstart, recend):
    """
    Remove event data not within recording range
    """
    def inRecording (o):
        return overlap ((recstart, recend), (o['startTimeCode'], o['endTimeCode']))
        
    event['chapters'] = sorted (filter (inRecording, event['chapters']), key = lambda x: x['startTimeCode'])
    for c in event['chapters']:
        c['speeches'] = sorted (filter (inRecording, c['speeches']), key = lambda x: x['startTimeCode'])
    return event

def formatTimedelta (d, precision=0, minlen=3):
    """
    Convert timedelta to string
    """
    sec = round (d.total_seconds ()*1000)
    div = [(1000, '{:03d}', ''), (60, '{:02d}', '.'), (60, '{:02d}', ':'), (24, '{:02d}', ':')]
    res = ""
    c = 1
    for factor, fmt, sep in div:
        sec, r = divmod (sec, factor)
        if c > precision:
            # no separator if nothing is there yet
            if not res:
                sep = ''
            res = fmt.format (r) + sep + res
        if sec < 1 and c >= minlen:
            break
        c += 1
    return res

def formatDescription (event, recstart, fd):
    """
    Create IA description
    """
    chapters = ['Recording of European Parliament plenary session on {humandate}.<br><a href="http://www.europarl.europa.eu/sides/getDoc.do?type=AGENDA&reference={date}&secondRef=SIT&language=EN">Agenda</a>, <a href="http://www.europarl.europa.eu/sides/getDoc.do?type=PV&reference={date}&secondRef=TOC&language=EN">Minutes</a>'.format (date=recstart.strftime ('%Y%m%d'), humandate=recstart.strftime ('%Y-%m-%d %H:%M %Z'))]
    for c in event['chapters']:
        start = c['startTimeCode']
        end = c['endTimeCode']
        if start < recstart:
            prefix = '{} (continued)'.format (c['title']['en'])
        else:
            prefix = '{}'.format (c['title']['en'])

        speeches = []
        for s in c['speeches']:
            start = s['startTimeCode']
            end = s['endTimeCode']
            continued = False
            if start < recstart:
                continued = True
                line = '{}'.format (formatTimedelta (timedelta (0), 1))
            else:
                line = '{}'.format (formatTimedelta (start-recstart, 1))
            line += ' <a href="http://www.europarl.europa.eu/meps/en/{}/mep.html">{} {}</a>'.format (s['externalId'], s['firstName'], s['lastName'])
            if continued:
                line += ' (continued)'
            speeches.append (line)
        chapters.append (prefix + '<br>' + '<br>'.join (speeches))
    print ('<br><br>'.join (chapters), file=fd)

def formatWebVTT (event, recstart, fd):
    """
    Create WebVTT subtitles with speaker and topic
    """
    def formatEvent (start, end, data):
        return '{} --> {}\n{}\n\n'.format (formatTimedelta (start), formatTimedelta (end), data)
        
    print ('WEBVTT\n', file=fd)
    for c in event['chapters']:
        # XXX: assuming the player can show multiple subtitles at the same time
        speeches = c['speeches']
        start = c['startTimeCode']
        if start < recstart:
            start = recstart
        relstart = start-recstart
        relend = c['endTimeCode']-recstart
        print (formatEvent (relstart, relend, 'Topic: {}'.format (c['title']['en'])), file=fd)

        for s in c['speeches']:
            start = s['startTimeCode']
            if start < recstart:
                start = recstart
            relstart = start-recstart
            relend = s['endTimeCode']-recstart
            print (formatEvent (relstart, relend, 'Speaker: {} {}'.format (s['firstName'], s['lastName'])), file=fd)

if __name__ == '__main__':
    import argparse, sys, configparser

    config = configparser.ConfigParser()
    config.read ('videobot_enricheuroparl.ini')

    parser = argparse.ArgumentParser(description='Enrich videobot’s europarl items with metadata.')
    parser.add_argument ('identifier', help='Internet Archive identifier')
    args = parser.parse_args()

    iaitem = requests.get ('https://archive.org/metadata/{}'.format (args.identifier)).json ()
    if 'error' in iaitem:
        print (iaitem['error'], file=sys.stderr)
        sys.exit (1)

    recordingtz = timezone (config['recording']['tz'])
    recordingstart = recordingtz.localize (parse (iaitem['metadata']['date'])).astimezone (brussels)
    recordingend = recordingstart+timedelta (seconds = int (config['recording']['length']))

    o = requests.get ('http://www.europarl.europa.eu/ep-live/en/json/plenary/video?date={}'.format (recordingstart.strftime ('%d-%m-%Y'))).json ()
    # save raw data
    with open ('{}.json'.format (args.identifier), 'w') as fd:
        json.dump (o, fd)

    event = filterRecording (convertTimestamps (o['event']), recordingstart, recordingend)
    #event = convertTimestamps (o['event'])
    with open ('{}.html'.format (args.identifier), 'w') as fd:
        formatDescription (event, recordingstart, fd)
    with open ('{}.vtt'.format (args.identifier), 'w') as fd:
        formatWebVTT (event, recordingstart, fd)