import os
from PyQt4.QtCore import *
from PyQt4.QtGui import *

from lxml import etree
from sfa.util.record import SfaRecord, SliceRecord, AuthorityRecord
from sfa.rspecs.rspec_parser import parse_rspec
from sface.config import config

class SfiData:
    def __init__(self):
        pass

    def getAuthorityHrns(self, type=None):
        names = []
        if os.path.exists(config.getAuthorityListFile()):
            xml = open(config.getAuthorityListFile()).read()
            tree = etree.fromstring(xml)
            records = tree.xpath("//recordlist/record")

            for record in records:
                recType = record.attrib.get("type", None)
                recHrn = record.attrib.get("hrn", None)
                if (type==None) or (type==recType):
                    names.append(recHrn)

        return names

    def getSliceRecord(self):
        rec_file = config.getSliceRecordFile()
        if os.path.exists(rec_file):
            xml = open(rec_file).read()
            rec = SliceRecord()
            rec.load_from_string(xml)
            return rec
        return None

    def purgeNonSliceResources(self, rspec):
        networks = rspec.get_networks()
        for network in networks:
            all_nodes = rspec.get_nodes(network)
            sliver_nodes = rspec.get_nodes_with_slivers(network)
            available_nodes = [ node for node in all_nodes if node not in sliver_nodes ]

            for node in available_nodes:
                node_elem = rspec.get_node_element(node, network)
                parent = node_elem.xpath("..")[0]
                parent.remove(node_elem)

    def getSliceRSpec(self):
        rspec_file = config.getSliceRSpecFile()
        if os.path.exists(rspec_file):
            xml = open(rspec_file).read()
            rspec = parse_rspec(xml)

            self.purgeNonSliceResources(rspec)

            return rspec
        return None

    def getResourcesRSpec(self):
        rspec_file = config.getResourcesRSpecFile()
        if os.path.exists(rspec_file):
            xml = open(rspec_file).read()
            return parse_rspec(xml)
        return None