import os
import sys
import psycopg2
from psycopg2 import sql
from psycopg2.extensions import ISOLATION_LEVEL_AUTOCOMMIT
import uuid
from datetime import datetime
import pytz
import pdb

tz = pytz.timezone('Europe/Madrid')

class Database():

    name = 'fediverse database library'

    def __init__(self, config_file=None, blocker_db=None, blocker_db_user=None, blocker_db_user_password=None):

        self.config_file = "config/db_config.txt"
        self.blocker_db = self.__get_parameter("blocker_db", self.config_file)
        self.blocker_db_user = self.__get_parameter("blocker_db_user", self.config_file)
        self.blocker_db_user_password = self.__get_parameter("blocker_db_user_password", self.config_file)

        db_setup = self.__check_dbsetup(self)

        if not db_setup:

            self.blocker_db = input("\nblocksoft database name: ")
            self.blocker_db_user = input("\nblocksoft database user: ")
            self.blocker_db_user_password = input("\nblocksoft database user password: ")

            self.__createdb(self)  
            self.__create_config(self)
            self.__write_config(self)

    def get_servers(self, software):

        servers_list = []

        try:

            conn = None

            conn = psycopg2.connect(database = self.blocker_db, user = self.blocker_db_user, password = "", host = "/var/run/postgresql", port = "5432")

            cur = conn.cursor()

            cur.execute("select server from servers where software=(%s)", (software,))

            rows = cur.fetchall()

            for row in rows:

                servers_list.append(row[0])

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            sys.exit(error)

        finally:

            if conn is not None:

                conn.close()
        
        return (servers_list)

    def write_server(self, server, api, software):

        now = datetime.now()

        insert_sql = "INSERT INTO servers(server, api, software, created_at) VALUES(%s, %s, %s, %s) ON CONFLICT DO NOTHING"

        conn = None

        try:

            conn = psycopg2.connect(database=self.blocker_db, user=self.blocker_db_user, password = self.blocker_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            cur.execute(insert_sql, (server, api, software, now))

            conn.commit()

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    def update_peer(self, server):

        now = datetime.now()

        update_sql = "UPDATE servers set updated_at=(%s) where server=(%s)"

        conn = None

        try:

            conn = psycopg2.connect(database=self.blocker_db, user=self.blocker_db_user, password = self.blocker_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            cur.execute(update_sql, (now, server))

            conn.commit()

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    def update_server(self, server, api):

        now = datetime.now()

        update_sql = "UPDATE servers set server=(%s), api=(%s), updated_at=(%s) where server=(%s)"

        conn = None

        try:

            conn = psycopg2.connect(database=self.blocker_db, user=self.blocker_db_user, password = self.blocker_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            cur.execute(update_sql, (server, api, now, server))

            conn.commit()

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    @staticmethod
    def __check_dbsetup(self):

        db_setup = False

        try:

            conn = None

            conn = psycopg2.connect(database = self.blocker_db, user = self.blocker_db_user, password = self.blocker_db_user_password, host = "/var/run/postgresql", port = "6432")

            db_setup = True

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        return db_setup

    @staticmethod
    def __createdb(self):

        conn = None

        try:

            conn = psycopg2.connect(dbname='postgres',
                user=self.blocker_db_user, host='',
                password=self.blocker_db_user_password)

            conn.set_isolation_level(ISOLATION_LEVEL_AUTOCOMMIT)

            cur = conn.cursor()

            print(f"Creating database {self.blocker_db}. Please wait...")

            cur.execute(sql.SQL("CREATE DATABASE {}").format(
                sql.Identifier(self.blocker_db))
            )
            print(f"Database {self.blocker_db} created!\n")

            self.__dbtables_schemes(self)

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    @staticmethod
    def __dbtables_schemes(self):

        db = self.blocker_db
        table = "servers"
        sql = "create table "+table+" (server varchar(200) PRIMARY KEY, api varchar(50), software varchar(50), created_at timestamptz, updated_at timestamptz, downs int)"
        self.__create_table(self, table, sql)

    @staticmethod
    def __create_table(self, table, sql):

        conn = None

        try:

            conn = psycopg2.connect(database = self.blocker_db, user = self.blocker_db_user, password = self.blocker_db_user_password, host = "/var/run/postgresql", port = "6432")

            cur = conn.cursor()

            print(f"Creating table {table}")

            cur.execute(sql)

            conn.commit()

            print(f"Table {table} created!\n")

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    def __get_parameter(self, parameter, config_file):

        if not os.path.isfile(config_file):
            print(f"File {config_file} not found..")
            return

        with open( config_file ) as f:
            for line in f:
                if line.startswith( parameter ):
                    return line.replace(parameter + ":", "").strip()

        print(f"{config_file} Missing parameter {parameter}")

        sys.exit(0)

    @staticmethod
    def __create_config(self):

        if not os.path.exists('config'):

            os.makedirs('config')

        if not os.path.exists(self.config_file):

            print(self.config_file + " created!")
            with open(self.config_file, 'w'): pass

    @staticmethod
    def __write_config(self):

        with open(self.config_file, 'a') as the_file:

            the_file.write(f'blocker_db: {self.blocker_db}\nblocker_db_user: {self.blocker_db_user}\nblocker_db_user_password: {self.blocker_db_user_password}')
            print(f"adding parameters to {self.config_file}\n")