import agent_util
import socket


def get_stats(host, port):
    size = 4096#1024
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect((host,int(port)))
    s.send("stats \n")
    data = s.recv(size)
    data = data.replace("STAT ","").replace("END", "")
    stats = dict(metric.split(" ",1) for metric in data.splitlines() if metric != '')

    s.close()

    return stats

class MemcachePlugin(agent_util.Plugin):
    textkey = "memcache"
    label = "Memcache"

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

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

        if not config:
            msg = "The [memcache] config block is not found in the agent config file."
            self.log.info(msg)
            status = agent_util.MISCONFIGURED

        if status == agent_util.SUPPORTED and (not "hostname" in config or not "port" in config):
            msg = "hostname or port missing from the [memcache] block in the agent config file."
            self.log.info(msg)
            status = agent_util.MISCONFIGURED


        if status == agent_util.SUPPORTED:
            try:
                stats = get_stats(config['hostname'], config['port'])
            except:
                status = agent_util.MISCONFIGURED
                msg = "Unable to get memcache status information, please double check hostname and port on config file."
                self.log.error(msg)

        metadata = {
            "bytes": {
                "label": "Number of bytes",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "B"
            },
            "bytes_read": {
                "label": "Total number of bytes read",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "B"
            },
            "bytes_written": {
                "label": "Total number of bytes sent",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "B"
            },
            "cmd_get": {
                "label": "Total number of retrieval requests (get operations)",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "requests"
            },
            "cmd_set": {
                "label": "Total number of storage requests (set operations)",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "requests"
            },
            "connection_structures": {
                "label": "Number of connection structures",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "structures"
            },
            "curr_connections": {
                "label": "Current number of open connections",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "connections"
            },
            "curr_items": {
                "label": "Current number of items",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "items"
            },
            "evictions": {
                "label": "Number of valid items removed from cache to free memory for new items",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "items"
            },
            "get_hits": {
                "label": "Number of keys that have been requested and found present",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "keys"
            },
            "get_misses": {
                "label": "Number of items that have been requested and not found",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "items"
            },
            "pointer_size": {
                "label": "Size of pointers",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "bits"
            },
            "rusage_system": {
                "label": "Total system time",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "seconds:microseconds"
            },
            "rusage_user": {
                "label": "Total user time",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "seconds:microseconds"
            },
            "threads": {
                "label": "Number of worker threads requested",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "threads"
            },
            "total_connections": {
                "label": "Total number of connections opened",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "connections"
            },
            "total_items": {
                "label": "Total number of items stored",
                "options": None,
                "status": status,
                "error_message": msg,
                "unit": "items"
            }
        }
        return metadata


    def check(self, textkey, data, config):
        stats = get_stats(config['hostname'], config['port'])
        res = 0

        try:
            res = int(stats[textkey])
        except:

            res = 0

        return res