#! /usr/bin/python 
"""NTriples Parsing Stuff"""

import string, re, urllib
import thing

import notation3    # N3 parsers and generators, and RDF generator
import md5, binascii  # for building md5 URIs

from thing import *

# Magic resources we know about
LITERAL_URI_prefix = "data:application/n3;"
DAML_LISTS = notation3.DAML_LISTS
RDF_type_URI = notation3.RDF_type_URI
DAML_equivalentTo_URI = notation3.DAML_equivalentTo_URI

NTP_NS_URI = "http://infomesh.net/2002/ntp#"

##############################################################################
# 
# N T P   B U I L T - I N s
# 
# This should be in a separate module, imported and called once by the user
# to register the code with the store
# 
#   Light Built-in classes

class BI_findall(LightBuiltIn, Function):
    def evaluateObject(self, store, context, subj, subj_py): 
        import re
        st, reg = subj_py
        res = list(re.compile(reg).findall(st))
        return store._fromPython(context, res)

def termToCWM(store, term): 
   from llyn import LITERAL, RESOURCE
   if term[0] == '"': return store.intern((LITERAL, term[1:-1]))
   elif term[0] == '<': return store.intern((RESOURCE, term[1:-1]))

class BI_strToTriple(LightBuiltIn, Function):
    def evaluateObject(self, store, context, subj, subj_py): 
        import re
        a = r'(<.*?>|_:\S+|\?\S+|"(?:\\"|[^"])*")[ \t]'
        rt = r'[ \t]*%s%s%s*.[ \t]*' % (a, a, a)
        x = list(re.compile(rt).findall(str(subj_py)))
        if len(x) > 0: 
           if 0: print 'triples:::', x
           for t in x: 
              store.storeQuad((context, # Store as P, S, O
                  termToCWM(store, t[1]), 
                  termToCWM(store, t[0]), 
                  termToCWM(store, t[2])))
        return None

#  Register the string built-ins with the store

def isString(x):
    return type(x) is type('') or type(x) is type(u'')

def register(store):
    str = store.internURI(NTP_NS_URI[:-1])
    
    str.internFrag("findall", BI_findall)
    str.internFrag("strToTriple", BI_strToTriple)