import agent_util
try:
    # Python 2.x
    import httplib
except:
    import http.client as httplib

class CouchPlugin(agent_util.Plugin):
    textkey = 'couch'
    label = 'CouchDB'
    description = 'Monitoring agent for CouchDB'

    @classmethod
    def get_metadata(self, config):
        status = agent_util.SUPPORTED
        msg = None
        response = None
        self.base_url = "/_stats"

        if not config:
            self.log.info("The [couch] config block is not found in the config file")
            return {}

        if "host" not in config or "port" not in config:
            msg = "The host and port settings were not found in the [couch] block of the agent config file."
            self.log.info(msg)
            status = agent_util.MISCONFIGURED

        if "base_url" in config:
            self.base_url = config["base_url"]

        if status == agent_util.SUPPORTED:

            try:
                couch_client = httplib.HTTPConnection(config['host'], config['port'])
                couch_client.request('GET', '/')
                response = couch_client.getresponse()
            except Exception:
                import sys
                _, exception, _ = sys.exc_info()
                status = agent_util.MISCONFIGURED
                msg = "Unable to connect to CouchDB server to request metrics"
                self.log.info('%s' % exception)

            if response and response.status != 200:
                status = agent_util.MISCONFIGURED
                mgs = 'CouchDB Stats not found at %s:%s' % (config['host'], config['port'])
                self.log.info(msg)

        return {
            'couchdb.database_writes': {
                'label': 'Number of times a database was changed',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'times',
            },
            'couchdb.database_reads': {
                'label': 'Number of times a document was read from a database',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'times',
            },
            'couchdb.open_databases': {
                'label': 'Number of open databases',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'databases',
            },
            'couchdb.open_os_files': {
                'label': 'Number of file descriptors CouchDB has open',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'files',
            },
            'couchdb.request_time': {
                'label': 'Length of a request inside CouchDB without MochiWeb',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'ms',
            },
            'httpd.bulk_requests': {
                'label': 'Number of bulk requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd.requests': {
                'label': 'Number of HTTP requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd.temporary_view_reads': {
                'label': 'Number of temporary view reads',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'reads',
            },
            'httpd.view_reads': {
                'label': 'Number of view reads',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'reads',
            },
            'httpd_request_methods.COPY': {
                'label': 'Number of HTTP COPY requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd_request_methods.DELETE': {
                'label': 'Number of HTTP DELETE requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd_request_methods.GET': {
                'label': 'Number of HTTP GET requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd_request_methods.HEAD': {
                'label': 'Number of HTTP HEAD requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd_request_methods.MOVE': {
                'label': 'Number of HTTP MOVE requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd_request_methods.POST': {
                'label': 'Number of HTTP POST requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd_request_methods.PUT': {
                'label': 'Number of HTTP PUT requests',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'requests',
            },
            'httpd_status_codes.200': {
                'label': 'Number of HTTP 200 OK responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.201': {
                'label': 'Number of HTTP 201 Created responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.202': {
                'label': 'Number of HTTP 202 Accepted responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.301': {
                'label': 'Number of HTTP 301 Moved Permanently responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.304': {
                'label': 'Number of HTTP 304 Not Modified responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.400': {
                'label': 'Number of HTTP 400 Bad Request responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.401': {
                'label': 'Number of HTTP 401 Unauthorized responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.403': {
                'label': 'Number of HTTP 403 Forbidden responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.404': {
                'label': 'Number of HTTP 404 Not Found responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.405': {
                'label': 'Number of HTTP 405 Method Not Allowed responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.409': {
                'label': 'Number of HTTP 409 Conflict responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.412': {
                'label': 'Number of HTTP 412 Precondition Failed responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
            'httpd_status_codes.500': {
                'label': 'Number of HTTP 500 Internal Server Error responses',
                'options': None,
                'status': status,
                'error_message': msg,
                'unit': 'responses',
            },
        }

    def check(self, textkey, data, config):
        stat_area, stat_name = textkey.split('.')
        url = '/'.join([self.base_url, stat_area, stat_name]) + '?range=60'
        try:
            couch_client = httplib.HTTPConnection(config["host"], config["port"])
            couch_client.request('GET', url)
        except Exception:
            return None
        response = couch_client.getresponse()
        stat = agent_util.json_loads(response.read())

        return stat[stat_area][stat_name]['current']