dd-re/recommendation_engine.py

'''
Recommendation Engine Example
1 Nov 2017, 0x2620
'''

from collections import defaultdict
import json
import logging
import os
import random
import time
import copy

import ox

from utils import run_async

logger = logging.getLogger(__name__)
verbose = True


class Engine:
    _pandora = None

    def __init__(self, path, **kwargs):
        self.path = path
        self.pandora_args = dict(
            url=kwargs.get('pandora', 'http://pandora.dmp/api/'),
            username=kwargs.get('username', 'dd.re'),
            password=kwargs.get('password', 'dd.re')
        )
        filename = os.path.join(self.path, 'playlists.json')
        if os.path.exists(filename):
            with open(filename) as f:
                self.playlists = json.load(f)
            # ## the following is for testing purpose.
            # for playlist in self.playlists:
            #     for clip in playlist["clips"]:
            #         clip["pass"] = bool(random.getrandbits(1))
        else:
            self.playlists = []

        filename = os.path.join(self.path, 'state.json')
        if os.path.exists(filename):
            with open(filename) as f:
                self.state = json.load(f)
        else:
            self.state = {
                'channels': {
                    'globalKeywords': {'locked': False, 'value': 8},
                    'userKeywords': {'locked': False, 'value': 8}
                },
                'globalKeywords': {},
            }
        if 'gridChange' not in self.state:
            self.state['gridChange'] = {
                'nextClip': {'locked': True, 'value': 4},
                'nextPlaylist': {'locked': False, 'value': 4},
                'staySame': {'locked': False, 'value': 8}
            }
        if 'userKeywordsWeights' not in self.state:
            self.state['userKeywordsWeights'] = {
                'themeTags': {'locked': False, 'value': 0.3},
                'characterTags': {'locked': False, 'value': 0.7}
            }
        self.update_keywords()

    @property
    def pandora(self):
        while not self._pandora:
            try:
                self._pandora = Pandora(**self.pandora_args)
            except:
                logger.error('failed to connect to pandora, retry in 10 seconds')
                time.sleep(10)
        return self._pandora

    def _patch_clips(self, clips):
        inpoints = {}
        for index, clip in enumerate(clips):
            video_id = clip['id'].split('/')[0]
            inpoints[video_id] = inpoints.get(video_id, []) + [{
                'index': index,
                'position': clip['in']
            }]
        for video_id in inpoints:
            for i, inpoint in enumerate(sorted(
                inpoints[video_id], key=lambda inpoint: inpoint['position']
            )):
                if i < len(inpoints[video_id]) - 1:
                    clips[inpoint['index']]['out'] = inpoints[video_id][i + 1]['position']
                else:
                    clips[inpoint['index']]['out'] = self.pandora.get(video_id, ['duration'])['duration']
        return clips


    def get_videos(self, user):
        # Update self_playlists first to reflect changes
        playlists = self.update_user_playlists(user)
        # Get the user keyword scores for debug view
        user_keywords = copy.deepcopy(user.get('keywords', {}))
        theme_tags = {k.lower():v for k,v in user_keywords.items() if not k.isupper()}
        character_tags = {k:v for k,v in user_keywords.items() if k.isupper()}
        top_user_keywords = sorted([(k,v) for (k,v) in theme_tags.items()], key=lambda kv: kv[1])[-5:]
        top_user_characters = sorted([(k,v) for (k,v) in character_tags.items()], key=lambda kv: kv[1])[-5:]

        if user.get('events', [{}])[0].get("event")=="login":
            return {
                'user': {
                    'keywords': user.get('keywords', {})
                },
                'videos': self.get_recommendations(playlists, user),
                "_debug": {
                    "top_user_keywords":top_user_keywords,
                    "top_user_characters":top_user_characters
                }
            }

        channels = {k: v.get('value', 0) for k, v in self.state['channels'].items()}
        sliders = {k: v.get('value', 0) for k, v in self.state['globalKeywords'].items()}
        grid_change = {k: v.get('value', 0) for k, v in self.state['gridChange'].items()}

        # check if there were grid events for all indexes.
        grid_events = {}
        (nc, np, ns) = (grid_change.get("nextClip"), grid_change.get("nextPlaylist"), grid_change.get("staySame"))
        video_num = nc + np + ns

        # # The version where the loop also extract play_index; requires "index" in play event data (previously unavailable):
        play_index = None
        for event in user.get('events', []):
            if event.get('event') == "grid" and event.get('data').get('index') not in grid_events:
                grid_events[event.get('data').get('index')] = event.get('data')
            if event.get('event') == "play" and event["data"].get("type") == "video" and not play_index:
                play_index = event.get('data').get('index')
            if len(grid_events) == video_num and play_index:
                break

        prev_grid_list = sorted([v for v in grid_events.values()], key=lambda k:k['index'])

        # if there were no grid events for all, initialize all grids.
        if len(prev_grid_list) < video_num:
            return {
                'user': {
                    'keywords': user.get('keywords', {})
                },
                'videos': self.get_recommendations(playlists, user),
                "_debug": {
                    "top_user_keywords":top_user_keywords,
                    "top_user_characters":top_user_characters
                }
            }

        else:
            if play_index is None:
                video_indx = list(range(video_num))
                random.shuffle(video_indx)
            else:
            # played index is excluded from the random shuffle and deterministically added to staySame pool.
                video_indx = [*range(play_index)]+[*range(play_index+1,video_num)]
                random.shuffle(video_indx)
                video_indx.append(play_index)

            next_clip_index = video_indx[:nc]
            next_playlist_index = video_indx[nc:nc+np]
            stay_same_index = video_indx[nc+np:]

            rec_list = []

            # Make sure the playlist exists for staySame pool; otherwise add it to nextPlaylist pool.
            for i in stay_same_index:
                if prev_grid_list[i].get("playlist") not in [playlist["name"] for playlist in playlists]:
                    next_playlist_index.append(stay_same_index)

            # select next clip for nextClip pool except when the playlist has only one clip. It skips the clip with "pass":True when selecting the next clip.
            for i in next_clip_index:
                if prev_grid_list[i].get("playlist") not in [playlist["name"] for playlist in playlists]:
                # add this to deal with the absence of "playlist" data in old grid event or the case where the playlist has been eliminated.
                    next_playlist_index.append(next_clip_index)
                    break
                else:
                    for playlist in playlists:
                        if playlist.get('name')== prev_grid_list[i].get('playlist'):
                            unwatched_clips_indx = [j for j in range(len(playlist["clips"])) if playlist["clips"][j].get("pass",False)!=True]
                            if len(playlist["clips"]) == 1:
                                next_playlist_index.append(i)
                                break
                            # Discuss how this behavour should be: should it switch to a new playlist if it is the end of the playlist clip sequence already?
                            elif prev_grid_list[i].get('playlistPosition', 0) + 1 == len(playlist['clips']):
                                if unwatched_clips_indx[0] != prev_grid_list[i]['playlistPosition']:
                                    playlist_pos = unwatched_clips_indx[0]
                                else:
                                    next_playlist_index.append(i)
                            else:
                                if len([j for j in unwatched_clips_indx if j > prev_grid_list[i]['playlistPosition']]) == 0:
                                    if unwatched_clips_indx[0] != prev_grid_list[i]['playlistPosition']:
                                        playlist_pos = unwatched_clips_indx[0]
                                    else:
                                        next_playlist_index.append(i)
                                else:
                                    playlist_pos = [j for j in unwatched_clips_indx if j > prev_grid_list[i]['playlistPosition']][0]


                            rec_list.append((i, {
                                'clips': playlist['clips'],
                                # 'position': random.randrange(len(playlist['clips'])),
                                'position': playlist_pos,
                                'name': playlist['name'],
                                'tags': playlist['tags'],
                            }))

            # randomly select playlists (excluding the playlists from the current grid once "playlist" is recorded for grid events)
            # for nextPlaylist pool.
            vids_exclude = [e.get("playlist") for e in prev_grid_list]
            while None in vids_exclude:
                vids_exclude.remove(None)
            video = self.get_recommendations(playlists, user, vids_exclude)
            rec_list += [(i, video[i]) for i in next_playlist_index]

            #staySame pool
            rec_list += [(i,{}) for i in stay_same_index]

            rec_list = sorted(rec_list, key=lambda k:k[0])
            videos_ = [e[1] for e in rec_list]
            return {
                'user': {
                    'keywords': user.get('keywords', {})
                },
                'videos': videos_,
                "_debug": {
                    "top_user_keywords":top_user_keywords,
                    "top_user_characters":top_user_characters
                }
            }


    def get_recommendations(self, playlists, user, vids_exclude = []):
        channels = {k: v.get('value', 0) for k, v in self.state['channels'].items()}
        sliders = {k: v.get('value', 0) for k, v in self.state['globalKeywords'].items()}
        gridChange = {k: v.get('value', 0) for k, v in self.state['gridChange'].items()}
        userKeywordsWeights = {k: v.get('value', 1) for k, v in self.state['userKeywordsWeights'].items()}

        # Exclude playlists from the most recent grid 
        if len(vids_exclude) > 0:
            for playlist in playlists:
                if playlist["name"] in vids_exclude:
                    playlists.remove(playlist)

        # For each playlist, compute user keyword score by theme and character tags
        user_keywords = copy.deepcopy(user.get('keywords', {}))
        theme_tags = {k.lower():v for k,v in user_keywords.items() if not k.isupper()}
        character_tags = {k:v for k,v in user_keywords.items() if k.isupper()}
        # manually modify some of the user keywords to match the playlist tags
        theme_tags["god"] = theme_tags.get("god - gods",0)
        theme_tags["visionary"] = theme_tags.get("visionary - enlightenment",0)
        theme_tags["enlightenment"] = theme_tags.get("visionary - enlightenment",0)
        character_tags["FEDOR MIKHAILOVICH SOFRONOV"] = character_tags.get("FYODOR MIKHAILOVICH SOFRONOV",0)
        character_tags["SHKABARNYA OLGA SERGEEVNA"] = character_tags.get("OLGA SERGEEVNA SHKABARNYA",0)
        character_tags["VICTORIA OLEGOVNA SKITSKAYA"] = character_tags.get("VIKTORIA OLEGOVNA SKITSKAYA",0)
        score = {}
        for playlist in playlists:
            score[playlist['name']] = random.random() * 0.001
            for tag in playlist['tags']:
                if tag in theme_tags:
                    score[playlist['name']] += theme_tags[tag] * userKeywordsWeights["themeTags"]
                elif tag in character_tags:
                    score[playlist['name']] += character_tags[tag] * userKeywordsWeights["characterTags"]
        # Select highest scoring playlists
        playlists = sorted(
            playlists,
            key=lambda playlist: -score[playlist['name']]
        )
        videos = playlists[:channels['userKeywords']]
        playlists = playlists[channels['userKeywords']:]
        # For each playlist, compute global keyword score
        score = {}
        for playlist in playlists:
            score[playlist['name']] = random.random()
            for tag in [tag for tag in playlist['tags'] if tag in sliders]:
                score[playlist['name']] += sliders[tag]
        # Select highest scoring playlists
        playlists = sorted(
            playlists,
            key=lambda playlist: -score[playlist['name']]
        )
        videos += playlists[:16 - channels['userKeywords']]
        # Shuffle playlists (randomize layout) and shift clips (randomize start)
        random.shuffle(videos)
        return [{
            'clips': video['clips'],
            'position': random.choice([i for i in range(len(video["clips"])) if video["clips"][i].get("pass",False)!=True]),
            'name': video['name'],
            'tags': video['tags'],
        } for video in videos]


    def update_user_playlists(self, user, watch_cutoff = 0.9):
    # Output: playlists with updated in/out time of clips that have been watched as well as "pass" indicators for the clips that has been watched for more than watch_cutoff.
    # Watched is defined as a video being played in full screen.
    # "watch_cutoff" parameter: the portion of the clip duration to be determined as watched the whole clip. should be [0,1]
    # + check (play, pause) pairs and eliminate unusual cases most likely due to a bug.
    # + If (play, pause) pairs exceed XX(80-90?) percent of the clip length, add "pass": True to the clip.
    # + Otherwise, find the last pause position of a clip and record it as "in" position of the clip.
    # + If clips are all marked as "pass" in a playlist, elliminate the playlist from the user playlists.
        playlists = copy.deepcopy(self.playlists)
        play = {}
        clip_max_dur = 10800 # = 3 hours; arbitrary max duration allowed for (pause time - play time) to detect outlier/bugs
        # The current max time of a clip duration is 10379.383333377269 from "DDLaunch: Erik Verlinde, Gravity as an emergent force (1956)"
        # A user could potentially spend more than 3 hours if they keep watching after the clip enters into the subsequent "scene"
        for event in user.get('events', [])[::-1]:
            if event["event"] == "play" and event["data"].get("type") == "video":
                play = event
            elif event["event"] == "pause" and play!={} and event["data"].get("type") == "video":
                if "position" not in play["data"]:
                    play = {}
                    break
                if play["data"].get("playlist") == event["data"].get("playlist"):
                    if event["data"]["position"] - play["data"]["position"] > 0 and event["data"]["position"] - play["data"]["position"] < clip_max_dur and event["data"].get("playlistPosition") == play["data"].get("playlistPosition") and event["data"].get("playlistPosition") is not None:
                        i = event["data"]["playlistPosition"]
                        for playlist in playlists:
                            if playlist["name"] == event["data"]["playlist"] and i < len(playlist["clips"]):
                                if play["data"]["position"] >= max(playlist["clips"][i]["in"] - 15, 0) and event["data"]["position"] <= playlist["clips"][i]["out"] + 15:
                                    # This assumes the (play, pause) fits inside the clip's (in, out) segment with +/- 15secs buffer. There were newer edits of clip positions with 12 seconds difference.
                                    # instances where this might not be the case: clip in/out may be largely edited (before after edit inconsistency); skip may trigger jump to a wrong clip (bug)
                                    if "orig_in" not in playlist["clips"][i]:
                                        cutoff_pos = (playlist["clips"][i]["out"]-playlist["clips"][i]["in"])*watch_cutoff + playlist["clips"][i]["in"]
                                    else:
                                        cutoff_pos = (playlist["clips"][i]["out"]-playlist["clips"][i]["orig_in"])*watch_cutoff + playlist["clips"][i]["orig_in"]

                                    if event["data"]["position"] >= cutoff_pos:
                                        playlist["clips"][i]["pass"] = True

                                    else:
                                        if "orig_in" not in playlist["clips"][i]:
                                            # record the original "in" position to calculate cutoff position in the future
                                            playlist["clips"][i]["orig_in"] = playlist["clips"][i]["in"]
                                        # update "in" position of the clip in the playlist
                                        playlist["clips"][i]["in"] = event["data"]["position"]
                                break
                play = {}

        for playlist in playlists.copy():
            unwatched = [clip for clip in playlist["clips"] if not clip.get("pass")]
            if not unwatched:
                playlists.remove(playlist)
        # If the number of playlists is reduced to 30, reset it to the original.
        if len(playlists) < 30:
            playlists = copy.deepcopy(self.playlists)

        return(playlists)


    def get_next(self, user, position):
        # Update self_playlists first to reflect changes
        playlists = self.update_user_playlists(user)
        
        grid_events = {}
        video_num = 16 

        for event in user.get('events', []):
            if event.get('event') == "grid" and event.get('data').get('index') not in grid_events:
                grid_events[event.get('data').get('index')] = event.get('data')
            if len(grid_events) == video_num:
                break
        prev_grid_list = sorted([v for v in grid_events.values()], key=lambda k:k['index'])
        vids_exclude = [e.get("playlist") for e in prev_grid_list]
        video = self.get_recommendations(playlists, user, vids_exclude)[position]
        return video

    def update_state(self, data):
        for key in data:
            if key in self.state:
                self.state[key].update(data[key])
            else:
                self.state[key] = data[key]
        self.save_state()
        return self.state

    def save_state(self):
        filename = os.path.join(self.path, 'state.json')
        with open(filename, 'w') as f:
            json.dump(self.state, f, indent=4, ensure_ascii=False, sort_keys=True)

    def update(self):
        # Get all storylines with tags
        storylines = [{
            'id': entity['id'],
            'name': entity['name'],
            'nodename': entity['nodename'],
            'tags': [t.strip() for t in entity['tags']]
        } for entity in self.pandora.find_entities({
            'conditions': [
                {'key': 'type', 'operator': '==', 'value': 'storylines'},
            ],
            'operator': '&'
        }, ['id', 'name', 'tags', 'nodename']) if entity.get('tags', []) and entity.get('nodename')]
        # Get list of storyline names
        names = list(set([storyline['name'] for storyline in storylines]))
        # Get list of items to use in DD
        items = [item['id'] for item in self.pandora.find({
            'conditions': [
                {'key': 'list', 'operator': '==', 'value': 'dau:DD'}
            ]
        }, ['id'])]
        # Get all clips annotated with storyline references
        clips = [clip for clip in self.pandora.find_annotations({
            'conditions': [
                {'key': 'layer', 'operator': '==', 'value': 'storylines'}
            ],
            'operator': '&'
        }, ['id', 'in', 'out', 'value']) if clip['value'] in names and clip['id'].split('/')[0] in items]
        # Get list of ids for videos with clips
        ids = list(set([clip['id'].split('/')[0] for clip in clips]))
        # Get and cache video data
        filename = os.path.join(self.path, 'videos.json')
        if os.path.exists(filename):
            with open(filename) as f:
                videos_ = json.loads(f.read())
                ids_ = [video['id'] for video in videos_]
        else:
            videos_, ids_ = [], []
        videos = sorted(videos_ + [
            self.pandora.get(id, ['code', 'id', 'order', 'title'])
            for id in ids if not id in ids_
        ], key=lambda video: int(video['order']))
        with open(filename, 'w') as f:
            f.write(json.dumps(videos, indent=4, sort_keys=True))
        # Get video order
        order = {video['id']: int(video['order']) for video in videos}
        # Sort clips
        clips = sorted(
            clips,
            key=lambda clip: (order[clip['id'].split('/')[0]], clip['in'])
        )
        # Get and cache playlists
        self.playlists = [playlist for playlist in [{
            'id': storyline['id'],
            'name': storyline['nodename'].strip(),
            'tags': storyline['tags'],
            'clips': [{
                'item': clip['id'].split('/')[0],
                'id': clip['id'],
                'in': clip['in'],
                'out': clip['out']
            } for clip in clips if clip['value'] == storyline['name']]
        } for storyline in storylines] if playlist['clips']]
        with open(os.path.join(self.path, 'playlists.json'), 'w') as f:
            f.write(json.dumps(self.playlists, indent=4, sort_keys=True))
        self.update_keywords()

    def update_keywords(self):
        changed = False
        if 'globalKeywords' not in self.state:
            self.state['globalKeywords'] = {}
            changed = True
        existing_tags = set()
        for playlist in self.playlists:
            for tag in playlist.get('tags', []):
                if not tag.isupper() and tag:
                    existing_tags.add(tag)
                if not tag.isupper() and tag not in self.state['globalKeywords']:
                    self.state['globalKeywords'][tag] = {'value': 0}
                    changed = True
        for tag in set(self.state['globalKeywords']) - existing_tags:
            del self.state['globalKeywords'][tag]
            changed = True
        if changed:
            self.save_state()

    @run_async
    def update_async(self):
        self.update()


class Pandora:

    # pan.do/ra API wrapper

    def __init__(self, url, username, password):
        self.api = ox.API(url)
        self.api.signin(username=username, password=password)

    def find(self, query, keys):
        # print('FIND', query, keys)
        return self.api.find({
            'keys': keys,
            'query': query,
            'range': [0, 1000000]
        })['data']['items']

    def find_annotations(self, query, keys):
        # print('FIND ANNOTATIONS', query, keys)
        return self.api.findAnnotations({
            'keys': keys,
            'query': query,
            'range': [0, 1000000]
        })['data']['items']

    def find_entities(self, query, keys):
        # print('FIND ENTITIES', query, keys)
        return self.api.findEntities({
            'keys': keys,
            'query': query,
            'range': [0, 1000000]
        })['data']['items']

    def get(self, id, keys):
        # print('GET', id, keys)
        return self.api.get({
            'id': id,
            'keys': keys
        })['data']


if __name__ == '__main__':
    engine = Engine('json')
    engine.update()