__filename__="filters.py"
__author__="Bob Mottram"
__license__="AGPL3+"
__version__="1.1.0"
__maintainer__="Bob Mottram"
__email__="bob@freedombone.net"
__status__="Production"

import os

def addFilter(baseDir: str,nickname: str,domain: str,words: str) -> bool:
    """Adds a filter for particular words within the content of a incoming posts
    """
    filtersFilename=baseDir+'/accounts/'+nickname+'@'+domain+'/filters.txt'
    if os.path.isfile(filtersFilename):
        if words in open(filtersFilename).read():
            return False
    filtersFile=open(filtersFilename, "a+")
    filtersFile.write(words+'\n')
    filtersFile.close()
    return True

def removeFilter(baseDir: str,nickname: str,domain: str, \
                 words: str) -> bool:
    """Removes a word filter
    """
    filtersFilename=baseDir+'/accounts/'+nickname+'@'+domain+'/filters.txt'
    if os.path.isfile(filtersFilename):
        if words in open(filtersFilename).read():
            with open(filtersFilename, 'r') as fp:
                with open(filtersFilename+'.new', 'w') as fpnew:
                    for line in fp:
                        line=line.replace('\n','')
                        if line!=words:
                            fpnew.write(line+'\n')
            if os.path.isfile(filtersFilename+'.new'):
                os.rename(filtersFilename+'.new',filtersFilename)
                return True
    return False

def isTwitterPost(content: str) -> bool:
    """Returns true if the given post content is a retweet or twitter crosspost
    """
    if '/twitter.' in content or '@twitter.' in content:
        return True
    elif '>RT <' in content:
        return True
    return False

def isFiltered(baseDir: str,nickname: str,domain: str,content: str) -> bool:
    """Should the given content be filtered out?
    This is a simple type of filter which just matches words, not a regex
    You can add individual words or use word1+word2 to indicate that two
    words must be present although not necessarily adjacent
    """
    # optionally remove retweets
    removeTwitter=baseDir+'/accounts/'+nickname+'@'+domain+'/.removeTwitter'
    if os.path.isfile(removeTwitter):
        if isTwitterPost(content):
            return True

    filtersFilename=baseDir+'/accounts/'+nickname+'@'+domain+'/filters.txt'
    if os.path.isfile(filtersFilename):
        with open(filtersFilename, 'r') as fp:
            for line in fp:
                filterStr=line.replace('\n','')
                if '+' not in filterStr:
                    if filterStr in content:
                        return True
                else:
                    filterWords=filterStr.replace('"','').split('+')
                    for word in filterWords:
                        if not word in content:
                            return False
                    return True
    return False