__filename__ = "follow.py"
__author__ = "Bob Mottram"
__license__ = "AGPL3+"
__version__ = "0.0.1"
__maintainer__ = "Bob Mottram"
__email__ = "bob@freedombone.net"
__status__ = "Production"

import json
import commentjson
from pprint import pprint
import os
import sys
from person import validNickname
from utils import domainPermitted
from utils import getDomainFromActor
from utils import getNicknameFromActor
from utils import getStatusNumber
from utils import followPerson
from posts import sendSignedJson
from posts import getPersonBox
from acceptreject import createAccept
from webfinger import webfingerHandle
from auth import createBasicAuthHeader
from session import postJson

def getFollowersOfPerson(baseDir: str, \
                         nickname: str,domain: str, \
                         followFile='following.txt') -> []:
    """Returns a list containing the followers of the given person
    Used by the shared inbox to know who to send incoming mail to
    """
    followers=[]
    if ':' in domain:
        domain=domain.split(':')[0]
    handle=nickname.lower()+'@'+domain.lower()
    if not os.path.isdir(baseDir+'/accounts/'+handle):
        return followers
    for subdir, dirs, files in os.walk(baseDir+'/accounts'):
        for account in dirs:
            filename = os.path.join(subdir, account)+'/'+followFile
            if account == handle or account.startswith('inbox@'):
                continue
            if not os.path.isfile(filename):
                continue
            with open(filename, 'r') as followingfile:
                for followingHandle in followingfile:
                    if followingHandle.replace('\n','')==handle:
                        if account not in followers:
                            followers.append(account)
                        break
    return followers

def followerOfPerson(baseDir: str,nickname: str, domain: str, \
                     followerNickname: str, followerDomain: str, \
                     federationList: [],debug :bool) -> bool:
    """Adds a follower of the given person
    """
    return followPerson(baseDir,nickname,domain, \
                        followerNickname,followerDomain, \
                        federationList,debug,'followers.txt')

def unfollowPerson(baseDir: str,nickname: str, domain: str, \
                   followNickname: str, followDomain: str, \
                   followFile='following.txt', \
                   debug=False) -> bool:
    """Removes a person to the follow list
    """
    if ':' in domain:
        domain=domain.split(':')[0]
    handle=nickname.lower()+'@'+domain.lower()
    handleToUnfollow=followNickname.lower()+'@'+followDomain.lower()
    if not os.path.isdir(baseDir+'/accounts'):
        os.mkdir(baseDir+'/accounts')
    if not os.path.isdir(baseDir+'/accounts/'+handle):
        os.mkdir(baseDir+'/accounts/'+handle)
    filename=baseDir+'/accounts/'+handle+'/'+followFile
    if not os.path.isfile(filename):
        if debug:
            print('DEBUG: follow file '+filename+' was not found')
        return False
    if handleToUnfollow not in open(filename).read():
        if debug:
            print('DEBUG: handle to unfollow '+handleToUnfollow+' is not in '+filename)
        return
    with open(filename, "r") as f:
        lines = f.readlines()
    with open(filename, "w") as f:
        for line in lines:
            if line.strip("\n") != handleToUnfollow:
                f.write(line)

def unfollowerOfPerson(baseDir: str,nickname: str,domain: str, \
                       followerNickname: str,followerDomain: str, \
                       debug=False) -> bool:
    """Remove a follower of a person
    """
    return unfollowPerson(baseDir,nickname,domain, \
                          followerNickname,followerDomain, \
                          'followers.txt',debug)

def clearFollows(baseDir: str,nickname: str,domain: str, \
                 followFile='following.txt') -> None:
    """Removes all follows
    """
    handle=nickname.lower()+'@'+domain.lower()
    if not os.path.isdir(baseDir+'/accounts'):
        os.mkdir(baseDir+'/accounts')
    if not os.path.isdir(baseDir+'/accounts/'+handle):
        os.mkdir(baseDir+'/accounts/'+handle)
    filename=baseDir+'/accounts/'+handle+'/'+followFile
    if os.path.isfile(filename):
        os.remove(filename)

def clearFollowers(baseDir: str,nickname: str,domain: str) -> None:
    """Removes all followers
    """
    clearFollows(baseDir,nickname, domain,'followers.txt')

def getNoOfFollows(baseDir: str,nickname: str,domain: str, \
                   authenticated: bool, \
                   followFile='following.txt') -> int:
    """Returns the number of follows or followers
    """
    # only show number of followers to authenticated
    # account holders
    if not authenticated:
        return 9999
    handle=nickname.lower()+'@'+domain.lower()
    filename=baseDir+'/accounts/'+handle+'/'+followFile
    if not os.path.isfile(filename):
        return 0
    ctr = 0
    with open(filename, "r") as f:
        lines = f.readlines()
        for line in lines:
            if '#' not in line:
                if '@' in line and '.' in line and not line.startswith('http'):
                    ctr += 1
                elif line.startswith('http') and '/users/' in line:
                    ctr += 1
    return ctr

def getNoOfFollowers(baseDir: str,nickname: str,domain: str,authenticated: bool) -> int:
    """Returns the number of followers of the given person
    """
    return getNoOfFollows(baseDir,nickname,domain,authenticated,'followers.txt')

def getFollowingFeed(baseDir: str,domain: str,port: int,path: str, \
                     httpPrefix: str, authenticated: bool,
                     followsPerPage=12, \
                     followFile='following') -> {}:
    """Returns the following and followers feeds from GET requests
    """
    # Show a small number of follows to non-authenticated viewers
    if not authenticated:
        followsPerPage=6

    if '/'+followFile not in path:
        return None
    # handle page numbers
    headerOnly=True
    pageNumber=None    
    if '?page=' in path:
        pageNumber=path.split('?page=')[1]
        if pageNumber=='true' or not authenticated:
            pageNumber=1
        else:
            try:
                pageNumber=int(pageNumber)
            except:
                pass
        path=path.split('?page=')[0]
        headerOnly=False
    
    if not path.endswith('/'+followFile):
        return None
    nickname=None
    if path.startswith('/users/'):
        nickname=path.replace('/users/','',1).replace('/'+followFile,'')
    if path.startswith('/@'):
        nickname=path.replace('/@','',1).replace('/'+followFile,'')
    if not nickname:
        return None
    if not validNickname(nickname):
        return None
            
    if port!=80 and port!=443:
        domain=domain+':'+str(port)

    if headerOnly:
        following = {
            '@context': 'https://www.w3.org/ns/activitystreams',
            'first': httpPrefix+'://'+domain+'/users/'+nickname+'/'+followFile+'?page=1',
            'id': httpPrefix+'://'+domain+'/users/'+nickname+'/'+followFile,
            'totalItems': getNoOfFollows(baseDir,nickname,domain,authenticated),
            'type': 'OrderedCollection'}
        return following

    if not pageNumber:
        pageNumber=1

    nextPageNumber=int(pageNumber+1)
    following = {
        '@context': 'https://www.w3.org/ns/activitystreams',
        'id': httpPrefix+'://'+domain+'/users/'+nickname+'/'+followFile+'?page='+str(pageNumber),
        'orderedItems': [],
        'partOf': httpPrefix+'://'+domain+'/users/'+nickname+'/'+followFile,
        'totalItems': 0,
        'type': 'OrderedCollectionPage'}        

    handle=nickname.lower()+'@'+domain.lower()
    filename=baseDir+'/accounts/'+handle+'/'+followFile+'.txt'
    if not os.path.isfile(filename):
        return following
    currPage=1
    pageCtr=0
    totalCtr=0
    with open(filename, "r") as f:
        lines = f.readlines()
        for line in lines:
            if '#' not in line:
                if '@' in line and '.' in line and not line.startswith('http'):
                    pageCtr += 1
                    totalCtr += 1
                    if currPage==pageNumber:
                        url = httpPrefix + '://' + line.lower().replace('\n','').split('@')[1] + \
                            '/users/' + line.lower().replace('\n','').split('@')[0]
                        following['orderedItems'].append(url)
                elif (line.startswith('http') or line.startswith('dat')) and '/users/' in line:
                    pageCtr += 1
                    totalCtr += 1
                    if currPage==pageNumber:
                        following['orderedItems'].append(line.lower().replace('\n',''))
            if pageCtr>=followsPerPage:
                pageCtr=0
                currPage += 1
    following['totalItems']=totalCtr
    lastPage=int(totalCtr/followsPerPage)
    if lastPage<1:
        lastPage=1
    if nextPageNumber>lastPage:
        following['next']=httpPrefix+'://'+domain+'/users/'+nickname+'/'+followFile+'?page='+str(lastPage)
    return following

def receiveFollowRequest(session,baseDir: str,httpPrefix: str, \
                         port: int,sendThreads: [],postLog: [], \
                         cachedWebfingers: {},personCache: {}, \
                         messageJson: {},federationList: [], \
                         debug : bool, \
                         acceptedCaps=["inbox:write","objects:read"]) -> bool:
    """Receives a follow request within the POST section of HTTPServer
    """
    if not messageJson['type'].startswith('Follow'):
        return False
    if not messageJson.get('actor'):
        if debug:
            print('DEBUG: follow request has no actor')
        return False
    if '/users/' not in messageJson['actor']:
        if debug:
            print('DEBUG: "users" missing from actor')            
        return False
    domain,tempPort=getDomainFromActor(messageJson['actor'])
    fromPort=port
    domainFull=domain
    if tempPort:
        fromPort=tempPort
        if tempPort!=80 and tempPort!=443:
            domainFull=domain+':'+str(tempPort)
    if not domainPermitted(domain,federationList):
        if debug:
            print('DEBUG: follower from domain not permitted - '+domain)
        return False
    nickname=getNicknameFromActor(messageJson['actor'])
    if not nickname:
        if debug:
            print('DEBUG: follow request does not contain a nickname')
        return False
    handle=nickname.lower()+'@'+domain.lower()
    if '/users/' not in messageJson['object']:
        if debug:
            print('DEBUG: "users" not found within object')
        return False
    domainToFollow,tempPort=getDomainFromActor(messageJson['object'])
    if not domainPermitted(domainToFollow,federationList):
        if debug:
            print('DEBUG: follow domain not permitted '+domainToFollow)
        return False
    domainToFollowFull=domainToFollow
    if tempPort:
        if tempPort!=80 and tempPort!=443:
            domainToFollowFull=domainToFollow+':'+str(tempPort)            
    nicknameToFollow=getNicknameFromActor(messageJson['object'])
    if not nicknameToFollow:
        if debug:
            print('DEBUG: follow request does not contain a nickname for the account followed')
        return False
    handleToFollow=nicknameToFollow.lower()+'@'+domainToFollow.lower()
    if domainToFollow==domain:
        if not os.path.isdir(baseDir+'/accounts/'+handleToFollow):
            if debug:
                print('DEBUG: followed account not found - '+ \
                      baseDir+'/accounts/'+handleToFollow)
            return False
        
    if not followerOfPerson(baseDir,nicknameToFollow,domainToFollowFull, \
                            nickname,domainFull,federationList,debug):
        if debug:
            print('DEBUG: '+nickname+'@'+domain+ \
                  ' is already a follower of '+ \
                  nicknameToFollow+'@'+domainToFollow)
        return False
    # send accept back
    if debug:
        print('DEBUG: sending Accept for follow request which arrived at '+ \
              nicknameToFollow+'@'+domainToFollow+' back to '+nickname+'@'+domain)
    personUrl=messageJson['actor']
    acceptJson=createAccept(baseDir,federationList, \
                            nicknameToFollow,domainToFollow,port, \
                            personUrl,'',httpPrefix,messageJson,acceptedCaps)
    if debug:
        pprint(acceptJson)
        print('DEBUG: sending follow Accept from '+ \
              nicknameToFollow+'@'+domainToFollow+ \
              ' port '+str(port)+' to '+ \
              nickname+'@'+domain+' port '+ str(fromPort))
    clientToServer=False
    return sendSignedJson(acceptJson,session,baseDir, \
                          nicknameToFollow,domainToFollow,port, \
                          nickname,domain,fromPort, '', \
                          httpPrefix,True,clientToServer, \
                          federationList, \
                          sendThreads,postLog,cachedWebfingers, \
                          personCache,debug)

def sendFollowRequest(session,baseDir: str, \
                      nickname: str,domain: str,port: int,httpPrefix: str, \
                      followNickname: str,followDomain: str, \
                      followPort: bool,followHttpPrefix: str, \
                      clientToServer: bool,federationList: [], \
                      sendThreads: [],postLog: [],cachedWebfingers: {}, \
                      personCache: {},debug : bool) -> {}:
    """Gets the json object for sending a follow request
    """    
    if not domainPermitted(followDomain,federationList):
        return None

    fullDomain=domain
    followActor=httpPrefix+'://'+domain+'/users/'+nickname    
    if port!=80 and port!=443:
        fullDomain=domain+':'+str(port)
        followActor=httpPrefix+'://'+domain+':'+str(port)+'/users/'+nickname

    requestDomain=followDomain
    if followPort!=80 and followPort!=443:
        requestDomain=followDomain+':'+str(followPort)

    statusNumber,published = getStatusNumber()
    
    followedId=followHttpPrefix+'://'+requestDomain+'/users/'+followNickname

    newFollowJson = {
        'type': 'Follow',
        'actor': followActor,
        'object': followedId,
        'to': [followedId],
        'cc': ['https://www.w3.org/ns/activitystreams#Public'],
        'published': published
    }

    sendSignedJson(newFollowJson,session,baseDir,nickname,domain,port, \
                   followNickname,followDomain,followPort, \
                   'https://www.w3.org/ns/activitystreams#Public', \
                   httpPrefix,True,clientToServer, \
                   federationList, \
                   sendThreads,postLog,cachedWebfingers,personCache, debug)

    return newFollowJson

def sendFollowRequestViaServer(session,fromNickname: str,password: str,
                               fromDomain: str,fromPort: int, \
                               followNickname: str,followDomain: str,followPort: int, \
                               httpPrefix: str, \
                               cachedWebfingers: {},personCache: {}, \
                               debug: bool) -> {}:
    """Creates a follow request via c2s
    """
    if not session:
        print('WARN: No session for sendFollowRequestViaServer')
        return 6

    fromDomainFull=fromDomain
    if fromPort!=80 and fromPort!=443:
        fromDomainFull=fromDomain+':'+str(fromPort)

    followDomainFull=followDomain
    if followPort!=80 and followPort!=443:
        followDomainFull=followDomain+':'+str(followPort)

    followActor=httpPrefix+'://'+fromDomainFull+'/users/'+fromNickname    
    followedId=httpPrefix+'://'+followDomainFull+'/users/'+followNickname

    statusNumber,published = getStatusNumber()
    newFollowJson = {
        'type': 'Follow',
        'actor': followActor,
        'object': followedId,
        'to': [followedId],
        'cc': ['https://www.w3.org/ns/activitystreams#Public'],
        'published': published
    }

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

    # lookup the inbox for the To handle
    wfRequest = webfingerHandle(session,handle,httpPrefix,cachedWebfingers)
    if not wfRequest:
        if debug:
            print('DEBUG: announce webfinger failed for '+handle)
        return 1

    postToBox='outbox'

    # get the actor inbox for the To handle
    inboxUrl,pubKeyId,pubKey,fromPersonId,sharedInbox,capabilityAcquisition = \
        getPersonBox(session,wfRequest,personCache,postToBox)
                     
    if not inboxUrl:
        if debug:
            print('DEBUG: No '+postToBox+' was found for '+handle)
        return 3
    if not fromPersonId:
        if debug:
            print('DEBUG: No actor was found for '+handle)
        return 4
    
    authHeader=createBasicAuthHeader(fromNickname,password)
     
    headers = {'host': fromDomain, \
               'Content-type': 'application/json', \
               'Authorization': authHeader}
    postResult = \
        postJson(session,newFollowJson,[],inboxUrl,headers,"inbox:write")
    #if not postResult:
    #    if debug:
    #        print('DEBUG: POST announce failed for c2s to '+inboxUrl)
    #    return 5

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

    return newFollowJson

def sendUnfollowRequestViaServer(session,fromNickname: str,password: str,
                                 fromDomain: str,fromPort: int, \
                                 followNickname: str,followDomain: str,followPort: int, \
                                 httpPrefix: str, \
                                 cachedWebfingers: {},personCache: {}, \
                                 debug: bool) -> {}:
    """Creates a unfollow request via c2s
    """
    if not session:
        print('WARN: No session for sendUnfollowRequestViaServer')
        return 6

    fromDomainFull=fromDomain
    if fromPort!=80 and fromPort!=443:
        fromDomainFull=fromDomain+':'+str(fromPort)
    followDomainFull=followDomain
    if followPort!=80 and followPort!=443:
        followDomainFull=followDomain+':'+str(followPort)

    followActor=httpPrefix+'://'+fromDomainFull+'/users/'+fromNickname    
    followedId=httpPrefix+'://'+followDomainFull+'/users/'+followNickname

    unfollowJson = {
        'type': 'Undo',
        'actor': followActor,
        'object': {
            'type': 'Follow',
            'actor': followActor,
            'object': followedId,
            'to': [followedId],
            'cc': ['https://www.w3.org/ns/activitystreams#Public']
        }
    }

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

    # lookup the inbox for the To handle
    wfRequest = webfingerHandle(session,handle,httpPrefix,cachedWebfingers)
    if not wfRequest:
        if debug:
            print('DEBUG: announce webfinger failed for '+handle)
        return 1

    postToBox='outbox'

    # get the actor inbox for the To handle
    inboxUrl,pubKeyId,pubKey,fromPersonId,sharedInbox,capabilityAcquisition = \
        getPersonBox(session,wfRequest,personCache,postToBox)
                     
    if not inboxUrl:
        if debug:
            print('DEBUG: No '+postToBox+' was found for '+handle)
        return 3
    if not fromPersonId:
        if debug:
            print('DEBUG: No actor was found for '+handle)
        return 4
    
    authHeader=createBasicAuthHeader(fromNickname,password)
     
    headers = {'host': fromDomain, \
               'Content-type': 'application/json', \
               'Authorization': authHeader}
    postResult = \
        postJson(session,unfollowJson,[],inboxUrl,headers,"inbox:write")
    #if not postResult:
    #    if debug:
    #        print('DEBUG: POST announce failed for c2s to '+inboxUrl)
    #    return 5

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

    return unfollowJson

def getFollowersOfActor(baseDir :str,actor :str,debug: bool) -> {}:
    """In a shared inbox if we receive a post we know who it's from
    and if it's addressed to followers then we need to get a list of those.
    This returns a list of account handles which follow the given actor
    and also the corresponding capability id if it exists
    """
    if debug:
        print('DEBUG: getting followers of '+actor)
    recipientsDict={}
    if ':' not in actor:
        return recipientsDict
    httpPrefix=actor.split(':')[0]
    nickname=getNicknameFromActor(actor)
    if not nickname:
        if debug:
            print('DEBUG: no nickname found in '+actor)
        return recipientsDict
    domain,port=getDomainFromActor(actor)
    if not domain:
        if debug:
            print('DEBUG: no domain found in '+actor)
        return recipientsDict
    actorHandle=nickname+'@'+domain
    if debug:
        print('DEBUG: searching for handle '+actorHandle)
    # for each of the accounts
    for subdir, dirs, files in os.walk(baseDir+'/accounts'):
        for account in dirs:
            if '@' in account and not account.startswith('inbox@'):
                followingFilename = os.path.join(subdir, account)+'/following.txt'
                if debug:
                    print('DEBUG: examining follows of '+account)
                    print(followingFilename)
                if os.path.isfile(followingFilename):
                    # does this account follow the given actor?
                    if debug:
                        print('DEBUG: checking if '+actorHandle+' in '+followingFilename)
                    if actorHandle in open(followingFilename).read():
                        if debug:
                            print('DEBUG: '+account+' follows '+actorHandle)
                        ocapFilename=baseDir+'/accounts/'+account+'/ocap/accept/'+httpPrefix+':##'+domain+':'+str(port)+'#users#'+nickname+'.json'
                        if debug:
                            print('DEBUG: checking capabilities of'+account)
                        if os.path.isfile(ocapFilename):                        
                            with open(ocapFilename, 'r') as fp:
                                ocapJson=commentjson.load(fp)
                                if ocapJson.get('id'):
                                    if debug:
                                        print('DEBUG: capabilities id found for '+account)
                
                                    recipientsDict[account]=ocapJson['id']
                                else:
                                    if debug:
                                        print('DEBUG: capabilities has no id attribute')
                                    recipientsDict[account]=None
                        else:
                            if debug:
                                print('DEBUG: No capabilities file found for '+account+' granted by '+actorHandle)
                                print(ocapFilename)
                            recipientsDict[account]=None
    return recipientsDict

def outboxUndoFollow(baseDir: str,messageJson: {},debug: bool) -> None:
    """When an unfollow request is received by the outbox from c2s
    This removes the followed handle from the following.txt file
    of the relevant account
    """
    if not messageJson.get('type'):
        return
    if not messageJson['type']=='Undo':
        return
    if not messageJson.get('object'):
        return
    if not isinstance(messageJson['object'], dict):
        return
    if not messageJson['object'].get('type'):
        return
    if not messageJson['object']['type']=='Follow':
        return
    if not messageJson['object'].get('object'):
        return
    if not messageJson['object'].get('actor'):
        return
    if not isinstance(messageJson['object']['object'], str):
        return
    if debug:
        print('DEBUG: undo follow arrived in outbox')

    nicknameFollower=getNicknameFromActor(messageJson['object']['actor'])
    domainFollower,portFollower=getDomainFromActor(messageJson['object']['actor'])
    domainFollowerFull=domainFollower
    if portFollower:
        if portFollower!=80 and portFollower!=443:
            domainFollowerFull=domainFollower+':'+str(portFollower)
    
    nicknameFollowing=getNicknameFromActor(messageJson['object']['object'])
    domainFollowing,portFollowing=getDomainFromActor(messageJson['object']['object'])
    domainFollowingFull=domainFollowing
    if portFollowing:
        if portFollowing!=80 and portFollowing!=443:
            domainFollowingFull=domainFollowing+':'+str(portFollowing)

    if unfollowPerson(baseDir,nicknameFollower,domainFollowerFull, \
                      nicknameFollowing,domainFollowingFull):
        if debug:
            print('DEBUG: '+nicknameFollower+' unfollowed '+nicknameFollowing+'@'+domainFollowingFull)
    else:
        if debug:
            print('WARN: '+nicknameFollower+' could not unfollow '+nicknameFollowing+'@'+domainFollowingFull)