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 = 'followers database library'

    def __init__(self, config_file=None, followers_db=None, followers_db_user=None, followers_db_user_password=None):

        self.config_file = "config/db_config.txt"
        self.followers_db = self.__get_parameter("followers_db", self.config_file)
        self.followers_db_user = self.__get_parameter("followers_db_user", self.config_file)
        self.followers_db_user_password = self.__get_parameter("followers_db_user_password", self.config_file)

        db_setup = self.__check_dbsetup(self)

        if not db_setup:

            self.followers_db = input("\nFollowers database name: ")
            self.followers_db_user = input("\nFollowers database user: ")
            self.followers_db_user_password = input("\nFollowers database user password: ")

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

    def find_follower(self, account):

        now = datetime.now()

        found = False

        select_sql = "select from followers where account=(%s)"

        conn = None

        try:

            conn = psycopg2.connect(database=self.followers_db, user=self.followers_db_user, password = self.followers_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            print(f'Searching follower {account}...')

            cur.execute(select_sql, (account,))

            row = cur.fetchone()

            if row != None:

                print(f'follower {account} is already in the database.')

                self.update_follower(account)

                found = True

            else:

                print(f'follower {account} not found! Adding it...')

                self.save_follower(account)

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    def find_unfollowers(self):

        now = datetime.now()

        unfollowers = []

        select_sql = "select account from followers where following='f' and updated_at > (now() + interval '2 hours') - interval '6 hours';"

        conn = None

        try:

            conn = psycopg2.connect(database=self.followers_db, user=self.followers_db_user, password = self.followers_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            print(f'Searching unfollowers...')

            cur.execute(select_sql)

            rows = cur.fetchall()

            if rows != None:

                for row in rows:

                    unfollowers.append(row[0])

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

        return unfollowers

    def save_follower(self, account):

        now = datetime.now()

        insert_sql = "INSERT INTO followers(account, updated_at, following) VALUES(%s,%s,%s) ON CONFLICT DO NOTHING"

        conn = None

        try:

            conn = psycopg2.connect(database=self.followers_db, user=self.followers_db_user, password = self.followers_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            print(f'Writing follower {account}...')

            cur.execute(insert_sql, (account, now, True))

            conn.commit()

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    def update_follower(self, account):

        now = datetime.now()

        update_sql = "UPDATE followers set updated_at=(%s), following=(%s) where account=(%s)"

        conn = None

        try:

            conn = psycopg2.connect(database=self.followers_db, user=self.followers_db_user, password = self.followers_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            print(f'Updating follower {account}...')

            cur.execute(update_sql, (now, True, account))

            conn.commit()

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    def last_total(self):

        now = datetime.now()

        last_local = 0

        last_remote = 0

        select_sql = "select local, remote from total order by updated_at desc limit 1"

        conn = None

        try:

            conn = psycopg2.connect(database=self.followers_db, user=self.followers_db_user, password = self.followers_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            cur.execute(select_sql)

            row = cur.fetchone()

            if row != None:

                last_local = row[0]

                last_remote = row[1]

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

        return last_local, last_remote

    def save_total(self, local, local_incr, remote, remote_incr):

        now = datetime.now()

        insert_sql = "INSERT INTO total(local, local_incr, remote, remote_incr, updated_at) VALUES(%s,%s,%s,%s,%s) ON CONFLICT DO NOTHING"

        conn = None

        try:

            conn = psycopg2.connect(database=self.followers_db, user=self.followers_db_user, password = self.followers_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            print(f'Writing totals {local} & {remote}...')

            cur.execute(insert_sql, (local, local_incr, remote, remote_incr, now))

            conn.commit()

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    def reset(self):

        now = datetime.now()

        update_sql = "UPDATE followers set following='f'"

        conn = None

        try:

            conn = psycopg2.connect(database=self.followers_db, user=self.followers_db_user, password = self.followers_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            cur.execute(update_sql)

            conn.commit()

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

    def totals(self):

        local_followers = 0

        remote_followers = 0

        local_sql = "select count(*) from followers where account not like '%@%' and following"

        remote_sql = "select count(*) from followers where account like '%@%' and following"

        conn = None

        try:

            conn = psycopg2.connect(database=self.followers_db, user=self.followers_db_user, password = self.followers_db_user_password, host="/var/run/postgresql", port="6432")

            cur = conn.cursor()

            cur.execute(local_sql)

            row = cur.fetchone()

            if row != None:

                local_followers = row[0]

            cur.execute(remote_sql)

            row = cur.fetchone()

            if row != None:

                remote_followers = row[0]

            cur.close()

        except (Exception, psycopg2.DatabaseError) as error:

            print(error)

        finally:

            if conn is not None:

                conn.close()

        return local_followers, remote_followers

    @staticmethod
    def __check_dbsetup(self):

        db_setup = False

        try:

            conn = None

            conn = psycopg2.connect(database = self.followers_db, user = self.followers_db_user, password = self.followers_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.followers_db_user, host='',
                password=self.followers_db_user_password)

            conn.set_isolation_level(ISOLATION_LEVEL_AUTOCOMMIT)

            cur = conn.cursor()

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

            cur.execute(sql.SQL("CREATE DATABASE {}").format(
                sql.Identifier(self.followers_db))
            )
            print(f"Database {self.followers_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.followers_db
        table = "followers"
        sql = "create table "+table+" (account varchar(100) PRIMARY KEY, updated_at timestamptz, following boolean)"
        self.__create_table(self, table, sql)

        table = "total"
        sql = "create table "+table+" (local int, local_incr int, remote int, remote_incr int, updated_at timestamptz)"
        self.__create_table(self, table, sql)

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

        conn = None

        try:

            conn = psycopg2.connect(database = self.followers_db, user = self.followers_db_user, password = self.followers_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'followers_db: {self.followers_db}\nfollowers_db_user: {self.followers_db_user}\nfollowers_db_user_password: {self.followers_db_user_password}')
            print(f"adding parameters to {self.config_file}\n")