"""
Basic protocol and dataplane test cases

It is recommended that these definitions be kept in their own
namespace as different groups of tests will likely define 
similar identifiers.

Current Assumptions:

  The function test_set_init is called with a complete configuration
dictionary prior to the invocation of any tests from this file.

  The switch is actively attempting to contact the controller at the address
indicated oin oft_config

"""

import time
import signal
import sys
import logging

import unittest

import oftest.controller as controller
import oftest.cstruct as ofp
import oftest.message as message
import oftest.dataplane as dataplane
import oftest.action as action

from testutils import *

#@var basic_port_map Local copy of the configuration map from OF port
# numbers to OS interfaces
basic_port_map = None
#@var basic_logger Local logger object
basic_logger = None
#@var basic_config Local copy of global configuration data
basic_config = None

test_prio = {}

def test_set_init(config):
    """
    Set up function for basic test classes

    @param config The configuration dictionary; see oft
    """

    global basic_port_map
    global basic_logger
    global basic_config

    basic_logger = logging.getLogger("basic")
    basic_logger.info("Initializing test set")
    basic_port_map = config["port_map"]
    basic_config = config

class SimpleProtocol(unittest.TestCase):
    """
    Root class for setting up the controller
    """

    def sig_handler(self, v1, v2):
        basic_logger.critical("Received interrupt signal; exiting")
        print "Received interrupt signal; exiting"
        self.clean_shutdown = False
        self.tearDown()
        sys.exit(1)

    def setUp(self):
        self.logger = basic_logger
        self.config = basic_config
        signal.signal(signal.SIGINT, self.sig_handler)
        basic_logger.info("** START TEST CASE " + str(self))
        self.controller = controller.Controller(
            host=basic_config["controller_host"],
            port=basic_config["controller_port"])
        # clean_shutdown should be set to False to force quit app
        self.clean_shutdown = True
        self.controller.start()
        #@todo Add an option to wait for a pkt transaction to ensure version
        # compatibilty?
        self.controller.connect(timeout=20)
        if not self.controller.active:
            print "Controller startup failed; exiting"
            sys.exit(1)
        basic_logger.info("Connected " + str(self.controller.switch_addr))

    def tearDown(self):
        basic_logger.info("** END TEST CASE " + str(self))
        self.controller.shutdown()
        #@todo Review if join should be done on clean_shutdown
        if self.clean_shutdown:
            self.controller.join()

    def runTest(self):
        # Just a simple sanity check as illustration
        basic_logger.info("Running simple proto test")
        self.assertTrue(self.controller.switch_socket is not None,
                        str(self) + 'No connection to switch')

    def assertTrue(self, cond, msg):
        if not cond:
            basic_logger.error("** FAILED ASSERTION: " + msg)
        unittest.TestCase.assertTrue(self, cond, msg)

test_prio["SimpleProtocol"] = 1

class SimpleDataPlane(SimpleProtocol):
    """
    Root class that sets up the controller and dataplane
    """
    def setUp(self):
        SimpleProtocol.setUp(self)
        self.dataplane = dataplane.DataPlane()
        for of_port, ifname in basic_port_map.items():
            self.dataplane.port_add(ifname, of_port)

    def tearDown(self):
        basic_logger.info("Teardown for simple dataplane test")
        SimpleProtocol.tearDown(self)
        self.dataplane.kill(join_threads=self.clean_shutdown)
        basic_logger.info("Teardown done")

    def runTest(self):
        self.assertTrue(self.controller.switch_socket is not None,
                        str(self) + 'No connection to switch')
        # self.dataplane.show()
        # Would like an assert that checks the data plane

class DataPlaneOnly(unittest.TestCase):
    """
    Root class that sets up only the dataplane
    """

    def sig_handler(self, v1, v2):
        basic_logger.critical("Received interrupt signal; exiting")
        print "Received interrupt signal; exiting"
        self.clean_shutdown = False
        self.tearDown()
        sys.exit(1)

    def setUp(self):
        self.clean_shutdown = False
        self.logger = basic_logger
        self.config = basic_config
        signal.signal(signal.SIGINT, self.sig_handler)
        basic_logger.info("** START DataPlaneOnly CASE " + str(self))
        self.dataplane = dataplane.DataPlane()
        for of_port, ifname in basic_port_map.items():
            self.dataplane.port_add(ifname, of_port)

    def tearDown(self):
        basic_logger.info("Teardown for simple dataplane test")
        self.dataplane.kill(join_threads=self.clean_shutdown)
        basic_logger.info("Teardown done")

    def runTest(self):
        basic_logger.info("DataPlaneOnly")
        # self.dataplane.show()
        # Would like an assert that checks the data plane

class Echo(SimpleProtocol):
    """
    Test echo response with no data
    """
    def runTest(self):
        request = message.echo_request()
        response, pkt = self.controller.transact(request)
        self.assertEqual(response.header.type, ofp.OFPT_ECHO_REPLY,
                         'response is not echo_reply')
        self.assertEqual(request.header.xid, response.header.xid,
                         'response xid != request xid')
        self.assertEqual(len(response.data), 0, 'response data non-empty')

class EchoWithData(SimpleProtocol):
    """
    Test echo response with short string data
    """
    def runTest(self):
        request = message.echo_request()
        request.data = 'OpenFlow Will Rule The World'
        response, pkt = self.controller.transact(request)
        self.assertEqual(response.header.type, ofp.OFPT_ECHO_REPLY,
                         'response is not echo_reply')
        self.assertEqual(request.header.xid, response.header.xid,
                         'response xid != request xid')
        self.assertEqual(request.data, response.data,
                         'response data does not match request')

class PacketIn(SimpleDataPlane):
    """
    Test packet in function

    Send a packet to each dataplane port and verify that a packet
    in message is received from the controller for each
    """
    def runTest(self):
        # Construct packet to send to dataplane
        # Send packet to dataplane, once to each port
        # Poll controller with expect message type packet in

        rc = delete_all_flows(self.controller, basic_logger)
        self.assertEqual(rc, 0, "Failed to delete all flows")

        for of_port in basic_port_map.keys():
            basic_logger.info("PKT IN test, port " + str(of_port))
            pkt = simple_tcp_packet()
            self.dataplane.send(of_port, str(pkt))
            #@todo Check for unexpected messages?
            count = 0
            while True:
                (response, raw) = self.controller.poll(ofp.OFPT_PACKET_IN, 2)
                if not response:  # Timeout
                    break
                if str(pkt) == response.data:  # Got match
                    break
                if not basic_config["relax"]:  # Only one attempt to match
                    break
                count += 1
                if count > 10:   # Too many tries
                    break

            self.assertTrue(response is not None, 
                            'Packet in message not received on port ' + 
                            str(of_port))
            if str(pkt) != response.data:
                basic_logger.debug("pkt  len " + str(len(str(pkt))) +
                                   ": " + str(pkt))
                basic_logger.debug("resp len " + 
                                   str(len(str(response.data))) + 
                                   ": " + str(response.data))

            self.assertEqual(str(pkt), response.data,
                             'Response packet does not match send packet' +
                             ' for port ' + str(of_port))

class PacketOut(SimpleDataPlane):
    """
    Test packet out function

    Send packet out message to controller for each dataplane port and
    verify the packet appears on the appropriate dataplane port
    """
    def runTest(self):
        # Construct packet to send to dataplane
        # Send packet to dataplane
        # Poll controller with expect message type packet in

        rc = delete_all_flows(self.controller, basic_logger)
        self.assertEqual(rc, 0, "Failed to delete all flows")

        # These will get put into function
        outpkt = simple_tcp_packet()
        of_ports = basic_port_map.keys()
        of_ports.sort()
        for dp_port in of_ports:
            msg = message.packet_out()
            msg.data = str(outpkt)
            act = action.action_output()
            act.port = dp_port
            self.assertTrue(msg.actions.add(act), 'Could not add action to msg')

            basic_logger.info("PacketOut to: " + str(dp_port))
            rv = self.controller.message_send(msg)
            self.assertTrue(rv == 0, "Error sending out message")

            exp_pkt_arg = None
            exp_port = None
            if basic_config["relax"]:
                exp_pkt_arg = outpkt
                exp_port = dp_port
            (of_port, pkt, pkt_time) = self.dataplane.poll(timeout=1, 
                                                           port_number=exp_port,
                                                           exp_pkt=exp_pkt_arg)

            self.assertTrue(pkt is not None, 'Packet not received')
            basic_logger.info("PacketOut: got pkt from " + str(of_port))
            if of_port is not None:
                self.assertEqual(of_port, dp_port, "Unexpected receive port")
            self.assertEqual(str(outpkt), str(pkt),
                             'Response packet does not match send packet')

class FlowStatsGet(SimpleProtocol):
    """
    Get stats 

    Simply verify stats get transaction
    """
    def runTest(self):
        basic_logger.info("Running StatsGet")
        basic_logger.info("Inserting trial flow")
        request = message.flow_mod()
        request.match.wildcards = ofp.OFPFW_ALL
        request.buffer_id = 0xffffffff
        rv = self.controller.message_send(request)
        self.assertTrue(rv != -1, "Failed to insert test flow")
        
        basic_logger.info("Sending flow request")
        request = message.flow_stats_request()
        request.out_port = ofp.OFPP_NONE
        request.table_id = 0xff
        request.match.wildcards = 0 # ofp.OFPFW_ALL
        response, pkt = self.controller.transact(request, timeout=2)
        self.assertTrue(response is not None, "Did not get response")
        basic_logger.debug(response.show())

class TableStatsGet(SimpleProtocol):
    """
    Get table stats 

    Simply verify table stats get transaction
    """
    def runTest(self):
        basic_logger.info("Running TableStatsGet")
        basic_logger.info("Inserting trial flow")
        request = message.flow_mod()
        request.match.wildcards = ofp.OFPFW_ALL
        request.buffer_id = 0xffffffff
        rv = self.controller.message_send(request)
        self.assertTrue(rv != -1, "Failed to insert test flow")
        
        basic_logger.info("Sending table stats request")
        request = message.table_stats_request()
        response, pkt = self.controller.transact(request, timeout=2)
        self.assertTrue(response is not None, "Did not get response")
        basic_logger.debug(response.show())

class FlowMod(SimpleProtocol):
    """
    Insert a flow

    Simple verification of a flow mod transaction
    """

    def runTest(self):
        basic_logger.info("Running " + str(self))
        request = message.flow_mod()
        request.match.wildcards = ofp.OFPFW_ALL
        request.buffer_id = 0xffffffff
        rv = self.controller.message_send(request)
        self.assertTrue(rv != -1, "Error installing flow mod")

class PortConfigMod(SimpleProtocol):
    """
    Modify a bit in port config and verify changed

    Get the switch configuration, modify the port configuration
    and write it back; get the config again and verify changed.
    Then set it back to the way it was.
    """

    def runTest(self):
        basic_logger.info("Running " + str(self))
        for of_port, ifname in basic_port_map.items(): # Grab first port
            break

        (hw_addr, config, advert) = \
            port_config_get(self.controller, of_port, basic_logger)
        self.assertTrue(config is not None, "Did not get port config")

        basic_logger.debug("No flood bit port " + str(of_port) + " is now " + 
                           str(config & ofp.OFPPC_NO_FLOOD))

        rv = port_config_set(self.controller, of_port,
                             config ^ ofp.OFPPC_NO_FLOOD, ofp.OFPPC_NO_FLOOD,
                             basic_logger)
        self.assertTrue(rv != -1, "Error sending port mod")

        # Verify change took place with same feature request
        (hw_addr, config2, advert) = \
            port_config_get(self.controller, of_port, basic_logger)
        basic_logger.debug("No flood bit port " + str(of_port) + " is now " + 
                           str(config2 & ofp.OFPPC_NO_FLOOD))
        self.assertTrue(config2 is not None, "Did not get port config2")
        self.assertTrue(config2 & ofp.OFPPC_NO_FLOOD !=
                        config & ofp.OFPPC_NO_FLOOD,
                        "Bit change did not take")
        # Set it back
        rv = port_config_set(self.controller, of_port, config, 
                             ofp.OFPPC_NO_FLOOD, basic_logger)
        self.assertTrue(rv != -1, "Error sending port mod")

if __name__ == "__main__":
    print "Please run through oft script:  ./oft --test_spec=basic"