import csv
import time
import Queue
import logging
import threading

from wally import utils
from wally.config import cfg_dict
from wally.sensors.api import (start_listener_thread,
                               deploy_and_start_sensors,
                               SensorConfig,
                               stop_and_remove_sensors)

logger = logging.getLogger("wally.sensors")
DEFAULT_RECEIVER_URL = "udp://{ip}:5699"


def save_sensors_data(data_q, mon_q, fd, data_store, source2roles_map):
    fd.write("\n")

    observed_nodes = set()
    fields_list_for_nodes = {}
    required_keys = set(['time', 'source_id', 'hostname'])

    try:
        csv_fd = csv.writer(fd)
        while True:
            val = data_q.get()
            if val is None:
                break

            addr, data = val
            if addr not in observed_nodes:
                mon_q.put(addr + (data['source_id'],))
                observed_nodes.add(addr)
                keys = set(data)
                assert required_keys.issubset(keys)
                keys -= required_keys

                fields_list_for_nodes[addr] = sorted(keys)
                csv_fd.writerow([addr[0], addr[1],
                                 data['source_id'], data['hostname']] +
                                fields_list_for_nodes[addr])

            csv_fd.writerow([addr[0], addr[1]] +
                            map(data.__getitem__,
                                ['time'] + fields_list_for_nodes[addr]))

            # fd.write(repr((addr, data)) + "\n")
            # source_id = data.pop('source_id')
            # rep_time = data.pop('time')
            # if 'testnode' in source2roles_map.get(source_id, []):
            #     sum_io_q = 0
            #     data_store.update_values(rep_time,
            #                              {"testnodes:io": sum_io_q},
            #                              add=True)
    except Exception:
        logger.exception("Error in sensors thread")
    logger.info("Sensors thread exits")


def get_sensors_config_for_nodes(cfg, nodes):
    monitored_nodes = []
    sensors_configs = []
    source2roles_map = {}

    receiver_url = cfg.get("receiver_url", DEFAULT_RECEIVER_URL)
    assert '{ip}' in receiver_url

    for role, sensors_str in cfg["roles_mapping"].items():
        sensors = [sens.strip() for sens in sensors_str.split(",")]

        collect_cfg = dict((sensor, {}) for sensor in sensors)

        for node in nodes:
            if role in node.roles:

                if node.monitor_ip is not None:
                    monitor_url = receiver_url.format(ip=node.monitor_ip)
                else:
                    ip = node.get_ip()
                    ext_ip = utils.get_ip_for_target(ip)
                    monitor_url = receiver_url.format(ip=ext_ip)

                source2roles_map[node.get_conn_id()] = node.roles
                monitored_nodes.append(node)
                sens_cfg = SensorConfig(node.connection,
                                        node.get_conn_id(),
                                        collect_cfg,
                                        source_id=node.get_conn_id(),
                                        monitor_url=monitor_url)
                sensors_configs.append(sens_cfg)

    return monitored_nodes, sensors_configs, source2roles_map


def start_sensor_process_thread(ctx, cfg, sensors_configs, source2roles_map):
    receiver_url = cfg.get('receiver_url', DEFAULT_RECEIVER_URL)
    sensors_data_q, stop_sensors_loop = \
        start_listener_thread(receiver_url.format(ip='0.0.0.0'))

    mon_q = Queue.Queue()
    fd = open(cfg_dict['sensor_storage'], "w")

    params = sensors_data_q, mon_q, fd, ctx.sensors_data, source2roles_map
    sensor_listen_th = threading.Thread(None, save_sensors_data, None,
                                        params)
    sensor_listen_th.daemon = True
    sensor_listen_th.start()

    def stop_sensors_receiver(cfg, ctx):
        stop_sensors_loop()
        sensors_data_q.put(None)
        sensor_listen_th.join()

    ctx.clear_calls_stack.append(stop_sensors_receiver)
    return mon_q


def deploy_sensors_stage(cfg, ctx, nodes=None, undeploy=True,
                         recv_timeout=10, ignore_nodata=False):
    if 'sensors' not in cfg:
        return

    cfg = cfg.get('sensors')

    if nodes is None:
        nodes = ctx.nodes

    monitored_nodes, sensors_configs, source2roles_map = \
        get_sensors_config_for_nodes(cfg, nodes)

    if len(monitored_nodes) == 0:
        logger.info("Nothing to monitor, no sensors would be installed")
        return

    if ctx.sensors_mon_q is None:
        logger.info("Start sensors data receiving thread")
        ctx.sensors_mon_q = start_sensor_process_thread(ctx, cfg,
                                                        sensors_configs,
                                                        source2roles_map)

    if undeploy:
        def remove_sensors_stage(cfg, ctx):
            _, sensors_configs, _ = \
                get_sensors_config_for_nodes(cfg['sensors'], nodes)
            stop_and_remove_sensors(sensors_configs)

        ctx.clear_calls_stack.append(remove_sensors_stage)

    num_monitoref_nodes = len(sensors_configs)
    logger.info("Deploing new sensors on {0} node(s)".format(
                                num_monitoref_nodes))

    deploy_and_start_sensors(sensors_configs)
    wait_for_new_sensors_data(ctx, monitored_nodes, recv_timeout,
                              ignore_nodata)


def wait_for_new_sensors_data(ctx, monitored_nodes, recv_timeout,
                              ignore_nodata):
    etime = time.time() + recv_timeout

    msg = "Waiting at most {0}s till all {1} nodes starts report sensors data"
    nodes_ids = set(node.get_conn_id() for node in monitored_nodes)
    logger.debug(msg.format(recv_timeout, len(nodes_ids)))

    # wait till all nodes start sending data
    while len(nodes_ids) != 0:
        tleft = etime - time.time()
        try:
            source_id = ctx.sensors_mon_q.get(True, tleft)[2]
        except Queue.Empty:
            if not ignore_nodata:
                msg = "Node(s) {0} not sending any sensor data in {1}s"
                msg = msg.format(", ".join(nodes_ids), recv_timeout)
                raise RuntimeError(msg)
            else:
                return

        if source_id not in nodes_ids:
            msg = "Receive sensors from extra node: {0}".format(source_id)
            logger.warning(msg)

        nodes_ids.remove(source_id)