import logging
import pydapper
import smtplib
import json
import os
from email.message import EmailMessage

from BreCal.schemas import model, defs
from BreCal.local_db import getPoolConnection
from BreCal.database.update_database import evaluate_shipcall_state
from BreCal.database.sql_queries import create_sql_query_shipcall_get
from BreCal.database.sql_queries import SQLQuery
from BreCal.database.sql_utils import get_notification_for_shipcall_and_type
from BreCal.services.email_handling import EmailHandler

import threading
import schedule
import time

options = {'past_days':7}

def UpdateShipcalls(options:dict = {'past_days':2}):
    """
    performs a single update step of every shipcall that matches the criteria.

    1.) opens an SQL connection
    2.) queries every shipcall that fulfills the {options} criteria
    3.) iterates over each shipcall
    4.) closes the SQL connection

    options:
        key: 'past_days'. Is used to execute a filtered query of all available shipcalls. Defaults to 2 (days)
    """
    pooledConnection = None
    try:
        pooledConnection = getPoolConnection()
        commands = pydapper.using(pooledConnection)

        # obtain data from the MYSQL database (uses 'options' to filter the resulting data by the ETA, considering those entries of 'past_days'-range)
        query = create_sql_query_shipcall_get(options)
        data = commands.query(query, model=model.Shipcall)

        data = [s for s in data if not s.canceled] # filter out canceled shipcalls

        # get the shipcall ids, which are of interest
        shipcall_ids = [dat.id for dat in data]

        # iterate over each shipcall id and (re-) evaluate it
        for shipcall_id in shipcall_ids:
            # apply 'Traffic Light' evaluation to obtain 'GREEN', 'YELLOW' or 'RED' evaluation state. The function internally updates the mysql database
            evaluate_shipcall_state(mysql_connector_instance=pooledConnection, shipcall_id=shipcall_id) # new_id (last insert id) refers to the shipcall id

    except Exception as ex:
        logging.error(ex)
    finally:
        if pooledConnection is not None:
            pooledConnection.close()
    return

def UpdateNotifications(cooldown_in_mins:int=10):
    """
    This function evaluates all notifications in state ("level") 0 which have been recently created. If a specified amount of time has passed the
    notification is updated to state 1 and a notification is received by the user
    """

    pooledConnection = None
    try:
        pooledConnection = getPoolConnection()
        commands = pydapper.using(pooledConnection)

        query = f"SELECT * FROM notification WHERE level = 0 AND created < TIMESTAMP(NOW() - INTERVAL {cooldown_in_mins} MINUTE)"
        data = commands.query(query, model=model.Notification)
        for notification in data:
            commands.execute("UPDATE notification SET level = 1 WHERE id = ?id?", param={"id":notification.id})

    except Exception as ex:
        logging.error(ex)
    finally:
        if pooledConnection is not None:
            pooledConnection.close()

def ClearNotifications(max_age_in_days:int=3):
    """
    This function clears all notifications in state ("level") 2 that are older than x days
    """

    pooledConnection = None
    try:
        pooledConnection = getPoolConnection()
        commands = pydapper.using(pooledConnection)

        query = f"DELETE FROM notification WHERE level = 2 and created < TIMESTAMP(NOW() - INTERVAL {max_age_in_days} DAY)"
        result = commands.execute(query)
        if(result > 0):
            logging.info(f"Deleted {result} notifications")

    except Exception as ex:
        logging.error(ex)
    finally:
        if pooledConnection is not None:
            pooledConnection.close()

def SendEmails(email_dict):
    """
    This function sends emails to all users in the emaildict
    """
    pooledConnection = None
    conn = None
    try:
        pooledConnection = getPoolConnection()
        commands = pydapper.using(pooledConnection)

        conn = smtplib.SMTP(defs.email_credentials["server"], defs.email_credentials["port"])
        conn.set_debuglevel(1) # set this to 0 to disable debug output to log
        conn.ehlo()
        conn.starttls()
        conn.ehlo()
        conn.login(defs.email_credentials["sender"], defs.email_credentials["password_send"])

        current_path = os.path.dirname(os.path.abspath(__file__))

        if not defs.message_types:
            f = open(os.path.join(current_path,"../msg/msg_types.json"), encoding='utf-8');
            defs.message_types = json.load(f)
            f.close()

        for user, notifications in email_dict.items():
            msg = EmailMessage()
            msg["Subject"] = '[Bremen calling] Notification'
            msg["From"] = defs.email_credentials["sender"]
            msg["To"] = user.user_email

            with open(os.path.join(current_path,'../msg/notification_template.html'), mode="r", encoding="utf-8") as file:
                body = file.read()

            replacement = ""

            for notification in notifications:

                message_type = next((x for x in defs.message_types if x["type"] == notification.type), None)
                if message_type is None:
                    logging.error(f"Message type {notification.type} not found")
                    continue

                with open(os.path.join(current_path,'../msg/notification_element.html'), mode="r", encoding="utf-8") as file:
                    element = file.read()
                element = element.replace("[[color]]", message_type["color"])
                element = element.replace("[[link]]", message_type["link"])

                # We want to show the following information for each notification:
                # Ship-name, Arr/Dep/Shift, ETA/ETD, berth
                sentinel = object()
                shipcall = commands.query_single_or_default("SELECT * FROM shipcall WHERE id = ?id?", sentinel, model=model.Shipcall, param={"id":notification.shipcall_id})
                if shipcall is sentinel:
                    logging.error(f"Shipcall with id {notification.shipcall_id} not found")
                    continue
                shipcall_type = defs.shipcall_types[shipcall.type]
                eta_text = shipcall.eta.strftime("%d.%m.%Y %H:%M") if shipcall.type == 1 else shipcall.etd.strftime("%d.%m.%Y %H:%M")

                ship = commands.query_single_or_default("SELECT * FROM ship WHERE id = ?id?", sentinel, model=model.Ship, param={"id":shipcall.ship_id})
                if ship is sentinel:
                    logging.error(f"Ship with id {shipcall.ship_id} not found")
                    continue
                berth_id = shipcall.arrival_berth_id if shipcall.type == 1 else shipcall.departure_berth_id
                berth = commands.query_single_or_default("SELECT * FROM berth WHERE id = ?id?", sentinel, model=model.Berth, param={"id":berth_id})
                berth_text = ""
                if berth is not sentinel:
                    berth_text = berth.name
                times = commands.query_single_or_default("SELECT * FROM times WHERE shipcall_id = ?id? and participant_type = 8", sentinel, model=model.Times, param={"id":notification.shipcall_id})
                if times is not sentinel:
                    eta_text = times.eta_berth.strftime("%d.%m.%Y %H:%M") if shipcall.type == 1 else times.etd_berth.strftime("%d.%m.%Y %H:%M")

                text = f"{ship.name} ({shipcall_type}) - {eta_text} - {berth_text}"

                element = element.replace("[[text]]", text)
                element = element.replace("[[notification_text]]", message_type["msg_text"])

                replacement += element

            body = body.replace("[[NOTIFICATION_ELEMENTS]]", replacement)
            msg.set_content(body, subtype='html', charset='utf-8', cte='8bit')

            conn.sendmail(defs.email_credentials["sender"], user.user_email, msg.as_string())

    except Exception as ex:
        logging.error(ex)
    finally:
        if conn is not None:
            conn.quit()
        if pooledConnection is not None:
            pooledConnection.close()


def SendNotifications():
    # perhaps this will be moved somewhere else later
    pooledConnection = None
    try:
        # find all notifications in level 1
        pooledConnection = getPoolConnection()
        query = "SELECT * from notification WHERE level = 1"
        commands = pydapper.using(pooledConnection)
        data = commands.query(query, model=model.Notification)
        if len(data) == 0:
            return

        # cache participants and users for performance beforehand
        query = "SELECT * from participant";
        participants = commands.query(query, model=model.Participant)

        email_dict = dict()
        users_dict = dict()
        user_query = "SELECT * from user"
        users = commands.query(user_query, model=model.User)
        for participant in participants:
            for user in users:
                if user.participant_id == participant.id:
                    if not participant.id in users_dict:
                        users_dict[participant.id] = []
                    users_dict[participant.id].append(user)
                    # break


        for notification in data:
            if not notification.participant_id: # no participant defined, this update goes to all participants of this shipcall
                p_query = "SELECT * from shipcall_participant_map where shipcall_id = ?id?"
                assigned_participants = commands.query(p_query, model=model.ShipcallParticipantMap, param={"id":notification.shipcall_id})
                for assigned_participant in assigned_participants:
                    users = users_dict[assigned_participant.participant_id]
                    for user in users:
                        # send notification to user
                        if user.notify_email:
                            if user not in email_dict:
                                email_dict[user] = []
                            email_dict[user].append(notification)
                        if user.notify_whatsapp:
                            # TBD
                            pass
                        if user.notify_signal:
                            # TBD
                            pass
            else:
                users = users_dict[notification.participant_id]
                for user in users:
                    # send notification to user
                    if user.notify_email and user.wants_notifications(notification.type):
                        if user not in email_dict:
                            email_dict[user] = []
                        email_dict[user].append(notification)
                    if user.notify_whatsapp and user.wants_notifications(notification.type):
                        # TBD
                        pass
                    if user.notify_signal and user.wants_notifications(notification.type):
                        # TBD
                        pass

            # mark as sent
            commands.execute("UPDATE notification SET level = 2 WHERE id = ?id?", param={"id":notification.id})

        # send emails (if any)
        if len(email_dict) > 0:
            SendEmails(email_dict)

    except Exception as ex:
        logging.error(ex)
    finally:
        if pooledConnection is not None:
            pooledConnection.close()

def add_function_to_schedule__update_shipcalls(interval_in_minutes:int, options:dict={'past_days':2}):
    kwargs_ = {"options":options}
    schedule.every(interval_in_minutes).minutes.do(UpdateShipcalls, **kwargs_)
    return

def add_function_to_evaluate_notifications(interval_in_minutes:int=1):
    schedule.every(1).minutes.do(UpdateNotifications, interval_in_minutes)
    return

def add_function_to_clear_notifications(interval_in_days:int=3):
    schedule.every(30).minutes.do(ClearNotifications, interval_in_days)
    return

def add_function_to_schedule_send_notifications(interval_in_minutes:int=1):
    schedule.every(interval_in_minutes).minutes.do(SendNotifications)
    return

def eval_next_24_hrs():
    pooledConnection = None
    try:
        pooledConnection = getPoolConnection()
        commands = pydapper.using(pooledConnection)
        query = SQLQuery.get_next24hrs_shipcalls()
        data = commands.query(query)
        nquery = "INSERT INTO notification (shipcall_id, participant_id, level, type, message) VALUES (?shipcall_id?, ?participant_id?, 0, 2, ?message?)"
        for shipcall in data:
            existing_notifications = get_notification_for_shipcall_and_type(shipcall["id"], 2)
            query = SQLQuery.get_shipcall_participant_map_by_shipcall_id()
            participants = commands.query(query, model=dict, param={"id":shipcall["id"]})
            for participant in participants:
                if participant["type"] == 1: # BSMD
                    continue
                # if participant["type"] == 32: # PORT AUTHORITY # Christin: Brake möchte sie vielleicht doch haben
                #    continue
                # check if "open" notification already exists
                found_notification = False
                for existing_notification in existing_notifications:
                    if existing_notification["participant_id"] == participant["id"] and existing_notification["level"] == 0:
                        found_notification = True
                        break
                if not found_notification:
                    commands.execute(nquery, param={"shipcall_id":shipcall["id"], "participant_id": participant["participant_id"], "message":shipcall["name"]})

    except Exception as ex:
        logging.error(ex)

    finally:
        if pooledConnection is not None:
            pooledConnection.close()

    return

def setup_schedule(update_shipcalls_interval_in_minutes:int=60):

    logging.getLogger('schedule').setLevel(logging.INFO); # set the logging level of the schedule module to INFO

    schedule.clear() # clear all routine jobs. This prevents jobs from being created multiple times

    # update the evaluation state in every recent shipcall
    add_function_to_schedule__update_shipcalls(update_shipcalls_interval_in_minutes)

    add_function_to_evaluate_notifications(defs.NOTIFICATION_COOLDOWN_MINS)

    add_function_to_clear_notifications(defs.NOTIFICATION_MAX_AGE_DAYS)

    schedule.every().day.at("09:00").do(eval_next_24_hrs)

    add_function_to_schedule_send_notifications(1)

    return


def run_schedule_permanently(latency:int=30):
    """permanently runs the scheduler. Any time a routine task is 'due', it will be executed. There is an interval between each iteration to reduce workload"""
    while True:
        schedule.run_pending()
        time.sleep(latency)
    return

def run_schedule_permanently_in_background(latency:int=30, thread_name:str="run_schedule_in_background"):
    """create a (daemon) thread in the background, which permanently executes the scheduled functions"""
    thread_names = [thread_.name for thread_ in threading.enumerate()]
    if not thread_name in thread_names:
        bg_thread = threading.Thread(target=run_schedule_permanently, name=thread_name, kwargs={"latency":latency})
        bg_thread.daemon = True # 'daemon': stops, when Python's main thread stops.
        bg_thread.start()
    return