import agent_util
import os
from agent_util import float
import sys

###################################3
# -*- coding: utf-8 -*-

import logging
import socket

logger = logging.getLogger(__name__)


class TimeoutException(Exception):
    pass


##################################


def get_status_headers(config):

    # branch logic based on socket vs http interface
    if "socket_cfg_file" in config:
        buffer = ""

        client = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
        client.connect(config["socket_cfg_file"])
        client.settimeout(2.0)
        out = "show stat" + "\n"
        client.send(out.encode("utf-8"))

        f = client.makefile()

        output = f.read().split("\n")
        client.close()

    if "stats_http_host" in config and "stats_http_port" in config and "stats_http_path" in config:

        auth_string = ""
        if "stats_http_user" in config and "stats_http_password" in config:
            auth_string = "%s:%s@" % (config["stats_http_user"], config["stats_http_password"])

        stats_endpoint = "http://%s%s:%s/%s?stats;csv;norefresh" % (auth_string,config["stats_http_host"], config["stats_http_port"], config["stats_http_path"].replace("/", ""))
        ret, output = agent_util.execute_command("curl '%s'" % stats_endpoint)

        # extract the values from the output
        output = output.split("\n")

    header_line = output[0].split(",")
    metric_values = []
    for values in output[1:]:
        if len(header_line) == len(values.split(",")):
            metric_values.append(dict(zip(header_line, values.split(","))))

    return metric_values, output


class HAProxyPlugin(agent_util.Plugin):
    textkey = "haproxy"
    label = "HAProxy"

    @classmethod
    def get_metadata(self, config):
        status = agent_util.SUPPORTED
        msg = None

        # check if haproxy is  installed
        installed = agent_util.which("haproxy")
        if not installed:
            msg = "haproxy binary not found"
            self.log.info(msg)
            status = agent_util.UNSUPPORTED
            return {}

        # if http interface is being used, check if curl is present
        if "stats_http_host" in config and not agent_util.which("curl", exc=False):
            self.log.info('curl not found!')
            status = agent_util.UNSUPPORTED
            msg = "Curl is not installed - please install"
            return {}

        # if sock interface is being used, check if we can access the file
        if "socket_cfg_file" in config:
            socket_cfg_file = config["socket_cfg_file"]
            if config.get("debug", False):
                self.log.debug("HAProxy socket file path %s" % socket_cfg_file)

            if not os.access(socket_cfg_file, os.W_OK):
                self.log.error(
                    "Agent does not have permission to access the HAProxy socket file. Please adjust permissions."
                )
                status = agent_util.MISCONFIGURED
                msg = "Agent does not have permission to access the HAProxy socket file. Please adjust permissions."
                return {}

        pxservers = set()
        svnames = set()
        try:
            metric_values = None
            output = None
            metric_values, output = get_status_headers(config)
            if config.get("debug", False):
                self.log.info("#####################################################")
                self.log.info("HAProxy command 'show stat' output:")
                self.log.info(output)
                self.log.info("#####################################################")

            for values in metric_values:
                pxname = values["# pxname"]
                svname = values["svname"]
                if svname == 'BACKEND':
                    # We skip the Backend checks
                    continue
                pxservers.add(pxname + " " + svname)

        except Exception:
            status = agent_util.MISCONFIGURED
            self.log.exception("Couldn't get haproxy status")
            self.log.info("#####################################################")
            self.log.info("HAProxy command 'show stat' output:")
            self.log.info(output)
            self.log.info("#####################################################")
            msg = "Couldn't get haproxy status, make sure haproxy is running, haproxy configuration file is valid and the status module is enabled"

        pxservers = list(pxservers)
        pxservers.sort()
        backend_pxservers = list(filter(lambda x: 'http_back' in x or 'BACKEND' in x, pxservers))
        pxservers += ['Total Backend', 'Total Frontend']

        if status is agent_util.SUPPORTED and not pxservers:
            status = agent_util.MISCONFIGURED
            msg = "No Proxy servers found."

        metadata = {
            "qcur": {
                "label": "Current HAProxy service queued requests ",
                "options": pxservers,
                "status": status,
                "error_message": msg,
            },
            "scur": {
                "label": "Current HAProxy service sessions",
                "options": pxservers,
                "status": status,
                "error_message": msg,
            },
            "stot": {
                "label": "HAProxy service sessions",
                "options": pxservers,
                "status": status,
                "error_message": msg,
            },
            "stot_rate": {
                "label": "HAProxy service session rate",
                "options": pxservers,
                "status": status,
                "error_message": msg,
                "unit": "sessions per second",
            },
            "bin": {
                "label": "Bytes In of HAProxy service",
                "options": pxservers,
                "status": status,
                "error_message": msg,
            },
            "bin_rate": {
                "label": "Rate of Bytes In of HAProxy service",
                "options": pxservers,
                "status": status,
                "error_message": msg,
                "unit": "B/s",
            },
            "bout": {
                "label": "Bytes Out of HAProxy service",
                "options": pxservers,
                "status": status,
                "error_message": msg,
            },
            "bout_rate": {
                "label": "Rate of Bytes Out of HAProxy service",
                "options": pxservers,
                "status": status,
                "error_message": msg,
                "unit": "B/s",
            },
            "ereq": {
                "label": "HAProxy service error requests",
                "options": pxservers,
                "status": status,
                "error_message": msg,
            },
            "eresp": {
                "label": "HAProxy service response errors",
                "options": pxservers,
                "status": status,
                "error_message": msg,
            },
            "econ": {
                "label": "HAProxy service connection errors",
                "options": pxservers,
                "status": status,
                "error_message": msg,
            },
            "rate": {
                    "label": "Sessions created per second",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
            },
            "req_rate": {
                    "label": "HTTP requests per second",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
            },
            "dreq": {
                    "label": "Requests denied due to ACL restrictions",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
            },
            "act": {
                    "label": "Number of HAProxy service active servers",
                    "options": backend_pxservers,
                    "status": status,
                    "error_message": msg,
            },
            "dresp": {
                    "label": "Responses denied due to ACL restrictions",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
            },
            "wredis": {
                    "label": "Redispatched requests",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
            },
            "wretr": {
                    "label": "Connection retries",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
            },
            "bck": {
                    "label": "Number of HAProxy service backup servers",
                    "options": backend_pxservers,
                    "status": status,
                    "error_message": msg,
            },
            "hrsp_1xx": {
                    "label": "http responses with 1xx code",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
                    "unit": "req/min"
            },
            "hrsp_2xx": {
                    "label": "http responses with 2xx code",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
                    "unit": "req/min"
            },
            "hrsp_3xx": {
                    "label": "http responses with 3xx code",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
                    "unit": "req/min"
            },
            "hrsp_4xx": {
                    "label": "http responses with 4xx code",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
                    "unit": "req/min"
            },
            "hrsp_5xx": {
                    "label": "http responses with 5xx code",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
                    "unit": "req/min"
            },
            "hrsp_other": {
                    "label": "http responses with other codes (protocol error)",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
                    "unit": "req/min"
            },
            "status": {
                    "label": "webserver status",
                    "options": pxservers,
                    "status": status,
                    "error_message": msg,
                    "unit": "boolean"
            }
        }
        return metadata

    def check(self, textkey, pxserver, config):
        metric_values, output = get_status_headers(config)

        res = 0
        isRate = False
        cached = 0
        cache = None
        if (textkey.endswith("_rate") and (textkey != "req_rate")) or textkey.startswith('hrsp'):
            isRate = True
            if not textkey.startswith('hrsp'):
                textkey = textkey.split("_")[0]
            self.log.debug('Cache textkey {}'.format(textkey))
            cache = self.get_cache_results(textkey, "haproxy")

        if pxserver.startswith('Total'):
            # Calculate the total of all services
            svname = pxserver.split(' ')[-1].upper()
            res = 0
            for metric in metric_values:
                if metric.get('svname') == svname:
                    self.log.debug('Total Calc SV {} Textkey {} PX {} Val {}'.format(
                        metric.get('svname'), textkey, metric['# pxname'], metric[textkey]
                    ))
                    try:
                        if metric[textkey] == "": continue
                        elif metric[textkey] == "UP" or metric[textkey] == "OPEN":
                            res = 1
                        elif metric[textkey] == "DOWN":
                            res = 0
                        else:
                            res += int(metric[textkey])
                    except Exception:
                        self.log.exception("Unable to parse metric value")
        else:
            # Checking a specific haproxy service metric.
            pxname = pxserver[: pxserver.rfind(" " + pxserver.split(" ")[-1])]
            svname = pxserver.split(" ")[-1]
            for metric in metric_values:
                self.log.debug("Metric value: %s " % metric[textkey])
                if pxname == metric["# pxname"] and svname == metric["svname"]:
                    res = metric[textkey]
                    if metric[textkey] in ('UP', 'OPEN'):
                        res = 1
                    elif 'DOWN' == metric[textkey]:
                        res = 0
                    else:
                        try:
                            res = int(res)
                        except:
                            return None

        if isRate is True:
            self.cache_result(textkey, "haproxy", res)
            if not cache:
                return None
            delta, cached_result = cache[0]
            if res < cached_result:
                return None
            val = (res - cached_result) / float(delta)
            if textkey.startswith('hrsp'):
                # We want actually requests per minute.
                val = val * 60
            return val
        return res