from .db_collector import DBCollector
from loguru import logger
import pymysql, json


class MysqlCollector(DBCollector):
    def __init__(self, db_url, user_name, password):
        self.VERSION_SQL = "SELECT @@GLOBAL.version;"
        self.PARAMETERS_SQL = "SHOW VARIABLES;"
        self.METRICS_SQL = "SHOW STATUS;"
        self.METRICS_SQL2 = "SELECT name, count FROM INFORMATION_SCHEMA.INNODB_METRICS where subsystem = 'transaction';"
        self.db_parameters = {}
        self.db_metrics = {}
        self.innodb_metrics = {}

        database = db_url.split("/")[1]
        host = db_url.split("/")[0].split(":")[0]
        port = int(db_url.split("/")[0].split(":")[1])
        db = pymysql.connect(host=host, user=user_name, password=password,
                             port=port, db=database, charset='utf8')
        cursor = db.cursor()
        try:
            # collect mysql version
            cursor.execute(self.VERSION_SQL)
            out = cursor.fetchall()
            self.version = out[0][0]

            # collect mysql parameters
            cursor.execute(self.PARAMETERS_SQL)
            out = cursor.fetchall()
            for row in out:
                self.db_parameters[row[0].lower()] = str(row[1]).lower()

            # collect mysql internal metrics
            cursor.execute(self.METRICS_SQL)
            out = cursor.fetchall()
            for row in out:
                self.db_metrics[row[0].lower()] = str(row[1]).lower()

            cursor.execute(self.METRICS_SQL2)
            out = cursor.fetchall()
            for row in out:
                self.innodb_metrics[row[0].lower()] = str(row[1]).lower()
        except Exception as e:
            logger.error(e)
            db.rollback()
        finally:
            db.close()

    def collect_parameters(self):
        parameters = {"global": {"global": self.db_parameters}, "local": None}
        return json.dumps(parameters)

    def collect_metrics(self):
        metrics = {"global": {"global": self.db_metrics, "innodb_metrics": self.innodb_metrics}, "local": None}
        return json.dumps(metrics)

    def collect_version(self):
        return self.version

    def collect_component_instances(self):
        pass