epicyon/reaction.py

__filename__ = "reaction.py"
__author__ = "Bob Mottram"
__license__ = "AGPL3+"
__version__ = "1.2.0"
__maintainer__ = "Bob Mottram"
__email__ = "bob@libreserver.org"
__status__ = "Production"
__module_group__ = "ActivityPub"

import os
import re
import urllib.parse
from pprint import pprint
from utils import hasObjectString
from utils import hasObjectStringObject
from utils import hasObjectStringType
from utils import removeDomainPort
from utils import hasObjectDict
from utils import hasUsersPath
from utils import getFullDomain
from utils import removeIdEnding
from utils import urlPermitted
from utils import getNicknameFromActor
from utils import getDomainFromActor
from utils import locatePost
from utils import undoReactionCollectionEntry
from utils import hasGroupType
from utils import localActorUrl
from utils import loadJson
from utils import saveJson
from utils import removePostFromCache
from utils import getCachedPostFilename
from utils import containsInvalidChars
from posts import sendSignedJson
from session import postJson
from webfinger import webfingerHandle
from auth import createBasicAuthHeader
from posts import getPersonBox

# the maximum number of reactions from individual actors which can be
# added to a post. Hence an adversary can't bombard you with sockpuppet
# generated reactions and make the post infeasibly large
maxActorReactionsPerPost = 64

# regex defining permissable emoji icon range
emojiRegex = re.compile(r'[\u263a-\U0001f645]')


def validEmojiContent(emojiContent: str) -> bool:
    """Is the given emoji content valid?
    """
    if not emojiContent:
        return False
    if len(emojiContent) > 2:
        return False
    if len(emojiRegex.findall(emojiContent)) == 0:
        return False
    if containsInvalidChars(emojiContent):
        return False
    return True


def _reaction(recentPostsCache: {},
              session, base_dir: str, federationList: [],
              nickname: str, domain: str, port: int,
              ccList: [], http_prefix: str,
              objectUrl: str, emojiContent: str,
              actorReaction: str,
              client_to_server: bool,
              send_threads: [], postLog: [],
              person_cache: {}, cachedWebfingers: {},
              debug: bool, project_version: str,
              signingPrivateKeyPem: str) -> {}:
    """Creates an emoji reaction
    actor is the person doing the reacting
    'to' might be a specific person (actor) whose post was reaction
    object is typically the url of the message which was reaction
    """
    if not urlPermitted(objectUrl, federationList):
        return None
    if not validEmojiContent(emojiContent):
        print('_reaction: Invalid emoji reaction: "' + emojiContent + '"')
        return

    fullDomain = getFullDomain(domain, port)

    newReactionJson = {
        "@context": "https://www.w3.org/ns/activitystreams",
        'type': 'EmojiReact',
        'actor': localActorUrl(http_prefix, nickname, fullDomain),
        'object': objectUrl,
        'content': emojiContent
    }
    if ccList:
        if len(ccList) > 0:
            newReactionJson['cc'] = ccList

    # Extract the domain and nickname from a statuses link
    reactionPostNickname = None
    reactionPostDomain = None
    reactionPostPort = None
    groupAccount = False
    if actorReaction:
        reactionPostNickname = getNicknameFromActor(actorReaction)
        reactionPostDomain, reactionPostPort = \
            getDomainFromActor(actorReaction)
        groupAccount = hasGroupType(base_dir, actorReaction, person_cache)
    else:
        if hasUsersPath(objectUrl):
            reactionPostNickname = getNicknameFromActor(objectUrl)
            reactionPostDomain, reactionPostPort = \
                getDomainFromActor(objectUrl)
            if '/' + str(reactionPostNickname) + '/' in objectUrl:
                actorReaction = \
                    objectUrl.split('/' + reactionPostNickname + '/')[0] + \
                    '/' + reactionPostNickname
                groupAccount = \
                    hasGroupType(base_dir, actorReaction, person_cache)

    if reactionPostNickname:
        postFilename = locatePost(base_dir, nickname, domain, objectUrl)
        if not postFilename:
            print('DEBUG: reaction base_dir: ' + base_dir)
            print('DEBUG: reaction nickname: ' + nickname)
            print('DEBUG: reaction domain: ' + domain)
            print('DEBUG: reaction objectUrl: ' + objectUrl)
            return None

        updateReactionCollection(recentPostsCache,
                                 base_dir, postFilename, objectUrl,
                                 newReactionJson['actor'],
                                 nickname, domain, debug, None,
                                 emojiContent)

        sendSignedJson(newReactionJson, session, base_dir,
                       nickname, domain, port,
                       reactionPostNickname,
                       reactionPostDomain, reactionPostPort,
                       'https://www.w3.org/ns/activitystreams#Public',
                       http_prefix, True, client_to_server, federationList,
                       send_threads, postLog, cachedWebfingers, person_cache,
                       debug, project_version, None, groupAccount,
                       signingPrivateKeyPem, 7165392)

    return newReactionJson


def reactionPost(recentPostsCache: {},
                 session, base_dir: str, federationList: [],
                 nickname: str, domain: str, port: int, http_prefix: str,
                 reactionNickname: str, reactionDomain: str, reactionPort: int,
                 ccList: [],
                 reactionStatusNumber: int, emojiContent: str,
                 client_to_server: bool,
                 send_threads: [], postLog: [],
                 person_cache: {}, cachedWebfingers: {},
                 debug: bool, project_version: str,
                 signingPrivateKeyPem: str) -> {}:
    """Adds a reaction to a given status post. This is only used by unit tests
    """
    reactionDomain = getFullDomain(reactionDomain, reactionPort)

    actorReaction = \
        localActorUrl(http_prefix, reactionNickname, reactionDomain)
    objectUrl = actorReaction + '/statuses/' + str(reactionStatusNumber)

    return _reaction(recentPostsCache,
                     session, base_dir, federationList,
                     nickname, domain, port,
                     ccList, http_prefix, objectUrl, emojiContent,
                     actorReaction, client_to_server,
                     send_threads, postLog, person_cache, cachedWebfingers,
                     debug, project_version, signingPrivateKeyPem)


def sendReactionViaServer(base_dir: str, session,
                          fromNickname: str, password: str,
                          fromDomain: str, fromPort: int,
                          http_prefix: str, reactionUrl: str,
                          emojiContent: str,
                          cachedWebfingers: {}, person_cache: {},
                          debug: bool, project_version: str,
                          signingPrivateKeyPem: str) -> {}:
    """Creates a reaction via c2s
    """
    if not session:
        print('WARN: No session for sendReactionViaServer')
        return 6
    if not validEmojiContent(emojiContent):
        print('sendReactionViaServer: Invalid emoji reaction: "' +
              emojiContent + '"')
        return 7

    fromDomainFull = getFullDomain(fromDomain, fromPort)

    actor = localActorUrl(http_prefix, fromNickname, fromDomainFull)

    newReactionJson = {
        "@context": "https://www.w3.org/ns/activitystreams",
        'type': 'EmojiReact',
        'actor': actor,
        'object': reactionUrl,
        'content': emojiContent
    }

    handle = http_prefix + '://' + fromDomainFull + '/@' + fromNickname

    # lookup the inbox for the To handle
    wfRequest = webfingerHandle(session, handle, http_prefix,
                                cachedWebfingers,
                                fromDomain, project_version, debug, False,
                                signingPrivateKeyPem)
    if not wfRequest:
        if debug:
            print('DEBUG: reaction webfinger failed for ' + handle)
        return 1
    if not isinstance(wfRequest, dict):
        print('WARN: reaction webfinger for ' + handle +
              ' did not return a dict. ' + str(wfRequest))
        return 1

    postToBox = 'outbox'

    # get the actor inbox for the To handle
    originDomain = fromDomain
    (inboxUrl, pubKeyId, pubKey, fromPersonId, sharedInbox, avatarUrl,
     displayName, _) = getPersonBox(signingPrivateKeyPem,
                                    originDomain,
                                    base_dir, session, wfRequest,
                                    person_cache,
                                    project_version, http_prefix,
                                    fromNickname, fromDomain,
                                    postToBox, 72873)

    if not inboxUrl:
        if debug:
            print('DEBUG: reaction no ' + postToBox +
                  ' was found for ' + handle)
        return 3
    if not fromPersonId:
        if debug:
            print('DEBUG: reaction no actor was found for ' + handle)
        return 4

    authHeader = createBasicAuthHeader(fromNickname, password)

    headers = {
        'host': fromDomain,
        'Content-type': 'application/json',
        'Authorization': authHeader
    }
    postResult = postJson(http_prefix, fromDomainFull,
                          session, newReactionJson, [], inboxUrl,
                          headers, 3, True)
    if not postResult:
        if debug:
            print('WARN: POST reaction failed for c2s to ' + inboxUrl)
        return 5

    if debug:
        print('DEBUG: c2s POST reaction success')

    return newReactionJson


def sendUndoReactionViaServer(base_dir: str, session,
                              fromNickname: str, password: str,
                              fromDomain: str, fromPort: int,
                              http_prefix: str, reactionUrl: str,
                              emojiContent: str,
                              cachedWebfingers: {}, person_cache: {},
                              debug: bool, project_version: str,
                              signingPrivateKeyPem: str) -> {}:
    """Undo a reaction via c2s
    """
    if not session:
        print('WARN: No session for sendUndoReactionViaServer')
        return 6

    fromDomainFull = getFullDomain(fromDomain, fromPort)

    actor = localActorUrl(http_prefix, fromNickname, fromDomainFull)

    newUndoReactionJson = {
        "@context": "https://www.w3.org/ns/activitystreams",
        'type': 'Undo',
        'actor': actor,
        'object': {
            'type': 'EmojiReact',
            'actor': actor,
            'object': reactionUrl,
            'content': emojiContent
        }
    }

    handle = http_prefix + '://' + fromDomainFull + '/@' + fromNickname

    # lookup the inbox for the To handle
    wfRequest = webfingerHandle(session, handle, http_prefix,
                                cachedWebfingers,
                                fromDomain, project_version, debug, False,
                                signingPrivateKeyPem)
    if not wfRequest:
        if debug:
            print('DEBUG: unreaction webfinger failed for ' + handle)
        return 1
    if not isinstance(wfRequest, dict):
        if debug:
            print('WARN: unreaction webfinger for ' + handle +
                  ' did not return a dict. ' + str(wfRequest))
        return 1

    postToBox = 'outbox'

    # get the actor inbox for the To handle
    originDomain = fromDomain
    (inboxUrl, pubKeyId, pubKey, fromPersonId, sharedInbox, avatarUrl,
     displayName, _) = getPersonBox(signingPrivateKeyPem,
                                    originDomain,
                                    base_dir, session, wfRequest,
                                    person_cache, project_version,
                                    http_prefix, fromNickname,
                                    fromDomain, postToBox,
                                    72625)

    if not inboxUrl:
        if debug:
            print('DEBUG: unreaction no ' + postToBox +
                  ' was found for ' + handle)
        return 3
    if not fromPersonId:
        if debug:
            print('DEBUG: unreaction no actor was found for ' + handle)
        return 4

    authHeader = createBasicAuthHeader(fromNickname, password)

    headers = {
        'host': fromDomain,
        'Content-type': 'application/json',
        'Authorization': authHeader
    }
    postResult = postJson(http_prefix, fromDomainFull,
                          session, newUndoReactionJson, [], inboxUrl,
                          headers, 3, True)
    if not postResult:
        if debug:
            print('WARN: POST unreaction failed for c2s to ' + inboxUrl)
        return 5

    if debug:
        print('DEBUG: c2s POST unreaction success')

    return newUndoReactionJson


def outboxReaction(recentPostsCache: {},
                   base_dir: str, http_prefix: str,
                   nickname: str, domain: str, port: int,
                   messageJson: {}, debug: bool) -> None:
    """ When a reaction request is received by the outbox from c2s
    """
    if not messageJson.get('type'):
        if debug:
            print('DEBUG: reaction - no type')
        return
    if not messageJson['type'] == 'EmojiReact':
        if debug:
            print('DEBUG: not a reaction')
        return
    if not hasObjectString(messageJson, debug):
        return
    if not messageJson.get('content'):
        return
    if not isinstance(messageJson['content'], str):
        return
    if not validEmojiContent(messageJson['content']):
        print('outboxReaction: Invalid emoji reaction: "' +
              messageJson['content'] + '"')
        return
    if debug:
        print('DEBUG: c2s reaction request arrived in outbox')

    messageId = removeIdEnding(messageJson['object'])
    domain = removeDomainPort(domain)
    emojiContent = messageJson['content']
    postFilename = locatePost(base_dir, nickname, domain, messageId)
    if not postFilename:
        if debug:
            print('DEBUG: c2s reaction post not found in inbox or outbox')
            print(messageId)
        return True
    updateReactionCollection(recentPostsCache,
                             base_dir, postFilename, messageId,
                             messageJson['actor'],
                             nickname, domain, debug, None, emojiContent)
    if debug:
        print('DEBUG: post reaction via c2s - ' + postFilename)


def outboxUndoReaction(recentPostsCache: {},
                       base_dir: str, http_prefix: str,
                       nickname: str, domain: str, port: int,
                       messageJson: {}, debug: bool) -> None:
    """ When an undo reaction request is received by the outbox from c2s
    """
    if not messageJson.get('type'):
        return
    if not messageJson['type'] == 'Undo':
        return
    if not hasObjectStringType(messageJson, debug):
        return
    if not messageJson['object']['type'] == 'EmojiReact':
        if debug:
            print('DEBUG: not a undo reaction')
        return
    if not messageJson['object'].get('content'):
        return
    if not isinstance(messageJson['object']['content'], str):
        return
    if not hasObjectStringObject(messageJson, debug):
        return
    if debug:
        print('DEBUG: c2s undo reaction request arrived in outbox')

    messageId = removeIdEnding(messageJson['object']['object'])
    emojiContent = messageJson['object']['content']
    domain = removeDomainPort(domain)
    postFilename = locatePost(base_dir, nickname, domain, messageId)
    if not postFilename:
        if debug:
            print('DEBUG: c2s undo reaction post not found in inbox or outbox')
            print(messageId)
        return True
    undoReactionCollectionEntry(recentPostsCache, base_dir, postFilename,
                                messageId, messageJson['actor'],
                                domain, debug, None, emojiContent)
    if debug:
        print('DEBUG: post undo reaction via c2s - ' + postFilename)


def updateReactionCollection(recentPostsCache: {},
                             base_dir: str, postFilename: str,
                             objectUrl: str, actor: str,
                             nickname: str, domain: str, debug: bool,
                             post_json_object: {},
                             emojiContent: str) -> None:
    """Updates the reactions collection within a post
    """
    if not post_json_object:
        post_json_object = loadJson(postFilename)
    if not post_json_object:
        return

    # remove any cached version of this post so that the
    # reaction icon is changed
    removePostFromCache(post_json_object, recentPostsCache)
    cachedPostFilename = getCachedPostFilename(base_dir, nickname,
                                               domain, post_json_object)
    if cachedPostFilename:
        if os.path.isfile(cachedPostFilename):
            try:
                os.remove(cachedPostFilename)
            except OSError:
                print('EX: updateReactionCollection unable to delete ' +
                      cachedPostFilename)

    obj = post_json_object
    if hasObjectDict(post_json_object):
        obj = post_json_object['object']

    if not objectUrl.endswith('/reactions'):
        objectUrl = objectUrl + '/reactions'
    if not obj.get('reactions'):
        if debug:
            print('DEBUG: Adding initial emoji reaction to ' + objectUrl)
        reactionsJson = {
            "@context": "https://www.w3.org/ns/activitystreams",
            'id': objectUrl,
            'type': 'Collection',
            "totalItems": 1,
            'items': [{
                'type': 'EmojiReact',
                'actor': actor,
                'content': emojiContent
            }]
        }
        obj['reactions'] = reactionsJson
    else:
        if not obj['reactions'].get('items'):
            obj['reactions']['items'] = []
        # upper limit for the number of reactions on a post
        if len(obj['reactions']['items']) >= maxActorReactionsPerPost:
            return
        for reactionItem in obj['reactions']['items']:
            if reactionItem.get('actor') and reactionItem.get('content'):
                if reactionItem['actor'] == actor and \
                   reactionItem['content'] == emojiContent:
                    # already reaction
                    return
        newReaction = {
            'type': 'EmojiReact',
            'actor': actor,
            'content': emojiContent
        }
        obj['reactions']['items'].append(newReaction)
        itlen = len(obj['reactions']['items'])
        obj['reactions']['totalItems'] = itlen

    if debug:
        print('DEBUG: saving post with emoji reaction added')
        pprint(post_json_object)
    saveJson(post_json_object, postFilename)


def htmlEmojiReactions(post_json_object: {}, interactive: bool,
                       actor: str, maxReactionTypes: int,
                       boxName: str, pageNumber: int) -> str:
    """html containing row of emoji reactions
    displayed at the bottom of posts, above the icons
    """
    if not hasObjectDict(post_json_object):
        return ''
    if not post_json_object.get('actor'):
        return ''
    if not post_json_object['object'].get('reactions'):
        return ''
    if not post_json_object['object']['reactions'].get('items'):
        return ''
    reactions = {}
    reactedToByThisActor = []
    for item in post_json_object['object']['reactions']['items']:
        emojiContent = item['content']
        emojiActor = item['actor']
        emojiNickname = getNicknameFromActor(emojiActor)
        emojiDomain, _ = getDomainFromActor(emojiActor)
        emojiHandle = emojiNickname + '@' + emojiDomain
        if emojiActor == actor:
            if emojiContent not in reactedToByThisActor:
                reactedToByThisActor.append(emojiContent)
        if not reactions.get(emojiContent):
            if len(reactions.items()) < maxReactionTypes:
                reactions[emojiContent] = {
                    "handles": [emojiHandle],
                    "count": 1
                }
        else:
            reactions[emojiContent]['count'] += 1
            if len(reactions[emojiContent]['handles']) < 32:
                reactions[emojiContent]['handles'].append(emojiHandle)
    if len(reactions.items()) == 0:
        return ''
    reactBy = removeIdEnding(post_json_object['object']['id'])
    htmlStr = '<div class="emojiReactionBar">\n'
    for emojiContent, item in reactions.items():
        count = item['count']

        # get the handles of actors who reacted
        handlesStr = ''
        item['handles'].sort()
        for handle in item['handles']:
            if handlesStr:
                handlesStr += '&#10;'
            handlesStr += handle

        if emojiContent not in reactedToByThisActor:
            baseUrl = actor + '?react=' + reactBy
        else:
            baseUrl = actor + '?unreact=' + reactBy
        baseUrl += '?actor=' + post_json_object['actor']
        baseUrl += '?tl=' + boxName
        baseUrl += '?page=' + str(pageNumber)
        baseUrl += '?emojreact='

        htmlStr += '  <div class="emojiReactionButton">\n'
        if count < 100:
            countStr = str(count)
        else:
            countStr = '99+'
        emojiContentStr = emojiContent + countStr
        if interactive:
            # urlencode the emoji
            emojiContentEncoded = urllib.parse.quote_plus(emojiContent)
            emojiContentStr = \
                '    <a href="' + baseUrl + emojiContentEncoded + \
                '" title="' + handlesStr + '">' + \
                emojiContentStr + '</a>\n'
        htmlStr += emojiContentStr
        htmlStr += '  </div>\n'
    htmlStr += '</div>\n'
    return htmlStr