# pylint: disable=c0111, c0103

import sys
import time
import traceback
from copy import copy

from sfa.trust.credential import Credential

from sfa.util.sfalogging import logger
from sfa.util.xrn import Xrn, urn_to_hrn
from sfa.util.version import version_core
from sfa.util.callids import Callids
from sfa.util.cache import Cache

from sfa.client.multiclient import MultiClient

from sfa.rspecs.version_manager import VersionManager
from sfa.rspecs.rspec import RSpec

from sfa.client.return_value import ReturnValue


class SliceManager:

    # the cache instance is a class member so it survives across incoming
    # requests
    cache = None

    def __init__(self, config):
        self.cache = None
        if config.SFA_SM_CACHING:
            if SliceManager.cache is None:
                SliceManager.cache = Cache()
            self.cache = SliceManager.cache

    def GetVersion(self, api, options):
        # peers explicitly in aggregates.xml
        peers = {peername: interface.get_url()
                 for (peername, interface) in api.aggregates.iteritems()
                 if peername != api.hrn}
        version_manager = VersionManager()
        ad_rspec_versions = []
        request_rspec_versions = []
        cred_types = [{'geni_type': 'geni_sfa',
                       'geni_version': str(i)} for i in range(4)[-2:]]
        for rspec_version in version_manager.versions:
            if rspec_version.content_type in ['*', 'ad']:
                ad_rspec_versions.append(rspec_version.to_dict())
            if rspec_version.content_type in ['*', 'request']:
                request_rspec_versions.append(rspec_version.to_dict())
        xrn = Xrn(api.hrn, 'authority+sm')
        version_more = {
            'interface': 'slicemgr',
            'sfa': 2,
            'geni_api': 3,
            'geni_api_versions':
                {'3': 'https://%s:%s'
                      % (api.config.SFA_SM_HOST, api.config.SFA_SM_PORT)},
            'hrn': xrn.get_hrn(),
            'urn': xrn.get_urn(),
            'peers': peers,
            # Accept operations that act on as subset of slivers in a given
            # state.
            'geni_single_allocation': 0,
            # Multiple slivers can exist and be incrementally added, including
            # those which connect or overlap in some way.
            'geni_allocate': 'geni_many',
            'geni_credential_types': cred_types,
        }
        sm_version = version_core(version_more)
        # local aggregate if present needs to have localhost resolved
        if api.hrn in api.aggregates:
            local_am_url = api.aggregates[api.hrn].get_url()
            sm_version['peers'][api.hrn] = local_am_url.replace(
                'localhost', sm_version['hostname'])
        return sm_version

    def drop_slicemgr_stats(self, rspec):
        try:
            stats_elements = rspec.xml.xpath('//statistics')
            for node in stats_elements:
                node.getparent().remove(node)
        except Exception as e:
            logger.warning("drop_slicemgr_stats failed: %s " % (str(e)))

    def add_slicemgr_stat(self, rspec, callname, aggname,
                          elapsed, status, exc_info=None):
        try:
            stats_tags = rspec.xml.xpath('//statistics[@call="%s"]' % callname)
            if stats_tags:
                stats_tag = stats_tags[0]
            else:
                stats_tag = rspec.xml.root.add_element(
                    "statistics", call=callname)

            stat_tag = stats_tag.add_element(
                "aggregate", name=str(aggname),
                elapsed=str(elapsed), status=str(status))

            if exc_info:
                exc_tag = stat_tag.add_element(
                    "exc_info", name=str(exc_info[1]))

                # formats the traceback as a set of xml elements
                tb = traceback.extract_tb(exc_info[2])
                for item in tb:
                    exc_frame = exc_tag.add_element(
                        "tb_frame", filename=str(item[0]),
                        line=str(item[1]), func=str(item[2]), code=str(item[3]))

        except Exception as e:
            logger.warning("add_slicemgr_stat failed on  %s: %s" %
                           (aggname, str(e)))

    def ListResources(self, api, creds, options):
        call_id = options.get('call_id')
        if Callids().already_handled(call_id):
            return ""

        version_manager = VersionManager()

        def _ListResources(aggregate, server, credential, options):
            forward_options = copy(options)
            tStart = time.time()
            try:
                version = api.get_cached_server_version(server)
                # force ProtoGENI aggregates to give us a v2 RSpec
                forward_options['geni_rspec_version'] = options.get(
                    'geni_rspec_version')
                result = server.ListResources(credential, forward_options)
                return {"aggregate": aggregate, "result": result,
                        "elapsed": time.time() - tStart, "status": "success"}
            except Exception as e:
                logger.log_exc("ListResources failed at %s" % (server.url))
                return {"aggregate": aggregate, "elapsed": time.time() - tStart,
                        "status": "exception", "exc_info": sys.exc_info()}

        # get slice's hrn from options
        xrn = options.get('geni_slice_urn', '')
        (hrn, type) = urn_to_hrn(xrn)
        if 'geni_compressed' in options:
            del(options['geni_compressed'])

        # get the rspec's return format from options
        rspec_version = version_manager.get_version(
            options.get('geni_rspec_version'))
        version_string = "rspec_%s" % (rspec_version)

        # look in cache first
        cached_requested = options.get('cached', True)
        if not xrn and self.cache and cached_requested:
            rspec = self.cache.get(version_string)
            if rspec:
                logger.debug(
                    "SliceManager.ListResources returns cached advertisement")
                return rspec

        # get the callers hrn
        valid_cred = api.auth.checkCredentials(creds, 'listnodes', hrn)[0]
        caller_hrn = Credential(cred=valid_cred).get_gid_caller().get_hrn()

        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential()
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            # prevent infinite loop. Dont send request back to caller
            # unless the caller is the aggregate's SM
            if caller_hrn == aggregate and aggregate != api.hrn:
                continue

            # get the rspec from the aggregate
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            multiclient.run(_ListResources, aggregate, server, [cred], options)

        results = multiclient.get_results()
        rspec_version = version_manager.get_version(
            options.get('geni_rspec_version'))
        if xrn:
            result_version = version_manager._get_version(
                rspec_version.type, rspec_version.version, 'manifest')
        else:
            result_version = version_manager._get_version(
                rspec_version.type, rspec_version.version, 'ad')
        rspec = RSpec(version=result_version)
        for result in results:
            self.add_slicemgr_stat(
                rspec, "ListResources", result["aggregate"], result["elapsed"],
                result["status"], result.get("exc_info", None))
            if result["status"] == "success":
                res = result['result']['value']
                try:
                    rspec.version.merge(ReturnValue.get_value(res))
                except Exception:
                    logger.log_exc(
                        "SM.ListResources: Failed to merge aggregate rspec")

        # cache the result
        if self.cache and not xrn:
            logger.debug("SliceManager.ListResources caches advertisement")
            self.cache.add(version_string, rspec.toxml())

        return rspec.toxml()

    def Allocate(self, api, xrn, creds, rspec_str, expiration, options):
        call_id = options.get('call_id')
        if Callids().already_handled(call_id):
            return ""

        version_manager = VersionManager()

        def _Allocate(aggregate, server, xrn, credential, rspec, options):
            tStart = time.time()
            try:
                # Need to call GetVersion at an aggregate to determine the supported
                # rspec type/format beofre calling CreateSliver at an Aggregate.
                #server_version = api.get_cached_server_version(server)
                # if 'sfa' not in server_version and 'geni_api' in server_version:
                    # sfa aggregtes support both sfa and pg rspecs, no need to convert
                    # if aggregate supports sfa rspecs. otherwise convert to pg rspec
                    #rspec = RSpec(RSpecConverter.to_pg_rspec(rspec, 'request'))
                    #filter = {'component_manager_id': server_version['urn']}
                    # rspec.filter(filter)
                    #rspec = rspec.toxml()
                result = server.Allocate(xrn, credential, rspec, options)
                return {"aggregate": aggregate, "result": result,
                        "elapsed": time.time() - tStart, "status": "success"}
            except:
                logger.log_exc(
                    'Something wrong in _Allocate with URL %s' % server.url)
                return {"aggregate": aggregate, "elapsed": time.time() - tStart,
                        "status": "exception", "exc_info": sys.exc_info()}

        # Validate the RSpec against PlanetLab's schema --disabled for now
        # The schema used here needs to aggregate the PL and VINI schemas
        # schema = "/var/www/html/schemas/pl.rng"
        rspec = RSpec(rspec_str)
    #    schema = None
    #    if schema:
    #        rspec.validate(schema)

        # if there is a <statistics> section, the aggregates don't care about it,
        # so delete it.
        self.drop_slicemgr_stats(rspec)

        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential()

        # get the callers hrn
        hrn, type = urn_to_hrn(xrn)
        valid_cred = api.auth.checkCredentials(creds, 'createsliver', hrn)[0]
        caller_hrn = Credential(cred=valid_cred).get_gid_caller().get_hrn()
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            # prevent infinite loop. Dont send request back to caller
            # unless the caller is the aggregate's SM
            if caller_hrn == aggregate and aggregate != api.hrn:
                continue
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            # Just send entire RSpec to each aggregate
            multiclient.run(_Allocate, aggregate, server, xrn,
                            [cred], rspec.toxml(), options)

        results = multiclient.get_results()
        manifest_version = version_manager._get_version(
            rspec.version.type, rspec.version.version, 'manifest')
        result_rspec = RSpec(version=manifest_version)
        geni_urn = None
        geni_slivers = []

        for result in results:
            self.add_slicemgr_stat(
                result_rspec, "Allocate", result["aggregate"], result["elapsed"],
                result["status"], result.get("exc_info", None))
            if result["status"] == "success":
                try:
                    res = result['result']['value']
                    geni_urn = res['geni_urn']
                    result_rspec.version.merge(
                        ReturnValue.get_value(res['geni_rspec']))
                    geni_slivers.extend(res['geni_slivers'])
                except Exception:
                    logger.log_exc(
                        "SM.Allocate: Failed to merge aggregate rspec")
        return {
            'geni_urn': geni_urn,
            'geni_rspec': result_rspec.toxml(),
            'geni_slivers': geni_slivers
        }

    def Provision(self, api, xrn, creds, options):
        call_id = options.get('call_id')
        if Callids().already_handled(call_id):
            return ""

        version_manager = VersionManager()

        def _Provision(aggregate, server, xrn, credential, options):
            tStart = time.time()
            try:
                # Need to call GetVersion at an aggregate to determine the supported
                # rspec type/format before calling CreateSliver at an
                # Aggregate.
                server_version = api.get_cached_server_version(server)
                result = server.Provision(xrn, credential, options)
                return {"aggregate": aggregate, "result": result,
                        "elapsed": time.time() - tStart, "status": "success"}
            except Exception:
                logger.log_exc(
                    'Something wrong in _Allocate with URL %s' % server.url)
                return {"aggregate": aggregate, "elapsed": time.time() - tStart,
                        "status": "exception", "exc_info": sys.exc_info()}

        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential()

        # get the callers hrn
        valid_cred = api.auth.checkCredentials(creds, 'createsliver', xrn)[0]
        caller_hrn = Credential(cred=valid_cred).get_gid_caller().get_hrn()
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            # prevent infinite loop. Dont send request back to caller
            # unless the caller is the aggregate's SM
            if caller_hrn == aggregate and aggregate != api.hrn:
                continue
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            # Just send entire RSpec to each aggregate
            multiclient.run(_Provision, aggregate,
                            server, xrn, [cred], options)

        results = multiclient.get_results()
        manifest_version = version_manager._get_version(
            'GENI', '3', 'manifest')
        result_rspec = RSpec(version=manifest_version)
        geni_slivers = []
        geni_urn = None
        for result in results:
            self.add_slicemgr_stat(
                result_rspec, "Provision", result["aggregate"], result["elapsed"],
                result["status"], result.get("exc_info", None))
            if result["status"] == "success":
                try:
                    res = result['result']['value']
                    geni_urn = res['geni_urn']
                    result_rspec.version.merge(
                        ReturnValue.get_value(res['geni_rspec']))
                    geni_slivers.extend(res['geni_slivers'])
                except:
                    logger.log_exc(
                        "SM.Provision: Failed to merge aggregate rspec")
        return {
            'geni_urn': geni_urn,
            'geni_rspec': result_rspec.toxml(),
            'geni_slivers': geni_slivers
        }

    def Renew(self, api, xrn, creds, expiration_time, options):
        call_id = options.get('call_id')
        if Callids().already_handled(call_id):
            return True

        def _Renew(aggregate, server, xrn, creds, expiration_time, options):
            try:
                result = server.Renew(xrn, creds, expiration_time, options)
                if type(result) != dict:
                    result = {'code': {'geni_code': 0}, 'value': result}
                result['aggregate'] = aggregate
                return result
            except:
                logger.log_exc(
                    'Something wrong in _Renew with URL %s' % server.url)
                return {'aggregate': aggregate, 'exc_info': traceback.format_exc(),
                        'code': {'geni_code': -1},
                        'value': False, 'output': ""}

        # get the callers hrn
        valid_cred = api.auth.checkCredentials(creds, 'renewsliver', xrn)[0]
        caller_hrn = Credential(cred=valid_cred).get_gid_caller().get_hrn()

        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential(minimumExpiration=31 * 86400)
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            # prevent infinite loop. Dont send request back to caller
            # unless the caller is the aggregate's SM
            if caller_hrn == aggregate and aggregate != api.hrn:
                continue
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            multiclient.run(_Renew, aggregate, server, xrn,
                            [cred], expiration_time, options)

        results = multiclient.get_results()

        geni_code = 0
        geni_output = ",".join([x.get('output', "") for x in results])
        geni_value = reduce(lambda x, y: x and y,
                            [result.get('value', False) for result in results],
                            True)
        for agg_result in results:
            agg_geni_code = agg_result['code'].get('geni_code', 0)
            if agg_geni_code:
                geni_code = agg_geni_code

        results = {'aggregates': results, 'code': {
            'geni_code': geni_code}, 'value': geni_value, 'output': geni_output}

        return results

    def Delete(self, api, xrn, creds, options):
        call_id = options.get('call_id')
        if Callids().already_handled(call_id):
            return ""

        def _Delete(server, xrn, creds, options):
            return server.Delete(xrn, creds, options)

        (hrn, type) = urn_to_hrn(xrn[0])
        # get the callers hrn
        valid_cred = api.auth.checkCredentials(creds, 'deletesliver', hrn)[0]
        caller_hrn = Credential(cred=valid_cred).get_gid_caller().get_hrn()

        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential()
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            # prevent infinite loop. Dont send request back to caller
            # unless the caller is the aggregate's SM
            if caller_hrn == aggregate and aggregate != api.hrn:
                continue
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            multiclient.run(_Delete, server, xrn, [cred], options)

        results = []
        for result in multiclient.get_results():
            results += ReturnValue.get_value(result)
        return results

    # first draft at a merging SliverStatus
    def Status(self, api, slice_xrn, creds, options):
        def _Status(server, xrn, creds, options):
            return server.Status(xrn, creds, options)

        call_id = options.get('call_id')
        if Callids().already_handled(call_id):
            return {}
        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential()
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            multiclient.run(_Status, server, slice_xrn, [cred], options)
        results = [ReturnValue.get_value(result)
                   for result in multiclient.get_results()]

        # get rid of any void result - e.g. when call_id was hit, where by
        # convention we return {}
        results = [
            result for result in results if result and result['geni_slivers']]

        # do not try to combine if there's no result
        if not results:
            return {}

        # otherwise let's merge stuff
        geni_slivers = []
        geni_urn = None
        for result in results:
            try:
                geni_urn = result['geni_urn']
                geni_slivers.extend(result['geni_slivers'])
            except Exception:
                logger.log_exc(
                    "SM.Provision: Failed to merge aggregate rspec")
        return {
            'geni_urn': geni_urn,
            'geni_slivers': geni_slivers
        }

    def Describe(self, api, creds, xrns, options):
        def _Describe(server, xrn, creds, options):
            return server.Describe(xrn, creds, options)

        call_id = options.get('call_id')
        if Callids().already_handled(call_id):
            return {}
        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential()
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            multiclient.run(_Describe, server, xrns, [cred], options)
        results = [ReturnValue.get_value(result)
                   for result in multiclient.get_results()]

        # get rid of any void result - e.g. when call_id was hit, where by
        # convention we return {}
        results = [
            result for result in results if result and result.get('geni_urn')]

        # do not try to combine if there's no result
        if not results:
            return {}

        # otherwise let's merge stuff
        version_manager = VersionManager()
        manifest_version = version_manager._get_version(
            'GENI', '3', 'manifest')
        result_rspec = RSpec(version=manifest_version)
        geni_slivers = []
        geni_urn = None
        for result in results:
            try:
                geni_urn = result['geni_urn']
                result_rspec.version.merge(
                    ReturnValue.get_value(result['geni_rspec']))
                geni_slivers.extend(result['geni_slivers'])
            except Exception:
                logger.log_exc(
                    "SM.Provision: Failed to merge aggregate rspec")
        return {
            'geni_urn': geni_urn,
            'geni_rspec': result_rspec.toxml(),
            'geni_slivers': geni_slivers
        }

    def PerformOperationalAction(self, api, xrn, creds, action, options):
        # get the callers hrn
        valid_cred = api.auth.checkCredentials(creds, 'createsliver', xrn)[0]
        caller_hrn = Credential(cred=valid_cred).get_gid_caller().get_hrn()

        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential()
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            # prevent infinite loop. Dont send request back to caller
            # unless the caller is the aggregate's SM
            if caller_hrn == aggregate and aggregate != api.hrn:
                continue
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            multiclient.run(server.PerformOperationalAction,
                            xrn, [cred], action, options)
        multiclient.get_results()
        return 1

    def Shutdown(self, api, xrn, creds, options=None):
        if options is None:
            options = {}
        xrn = Xrn(xrn)
        # get the callers hrn
        valid_cred = api.auth.checkCredentials(creds, 'stopslice', xrn.hrn)[0]
        caller_hrn = Credential(cred=valid_cred).get_gid_caller().get_hrn()

        # attempt to use delegated credential first
        cred = api.getDelegatedCredential(creds)
        if not cred:
            cred = api.getCredential()
        multiclient = MultiClient()
        for aggregate in api.aggregates:
            # prevent infinite loop. Dont send request back to caller
            # unless the caller is the aggregate's SM
            if caller_hrn == aggregate and aggregate != api.hrn:
                continue
            interface = api.aggregates[aggregate]
            server = api.server_proxy(interface, cred)
            multiclient.run(server.Shutdown, xrn.urn, cred)
        multiclient.get_results()
        return 1