#!/bin/python3
#########################
#
# timeTrack.py
# by 4nima
# v.2.0.0
#
#########################
# simple time tracking with database 
#########################

import datetime
import sqlite3
import json
import os
import logging

# Main class
class TimeTrack:
    def __init__(self, DATABASE='timetrack.db', CONFIG='timetrack.conf'):
        self.DATABASE   = DATABASE
        self.CONFIG     = CONFIG
        self.USERID     = 0
        self.USERNAME   = ''
        self.OLDEVENT   = 2
        self.LOGFILE    = 'timetrack.log'
        logging.basicConfig(
            filename=self.LOGFILE,
            level=logging.DEBUG, 
            format='%(asctime)s - %(process)d-%(levelname)s: %(message)s',
            datefmt='%Y-%m-%d %H:%M:%S'
        )
        self.db_setup()
        self.load_config()

    ## Prepartation
    ### Check OS and clear screen
    def clear_screen(self):
        if os.name == 'posix':
            logging.debug('Unix/Linux system detected')
            _ = os.system('clear')
        else:
            logging.debug('Winwos System detected')
            _ = os.system('cls')
            
    ### Creates a database if none is found
    def db_setup(self):
        if os.path.isfile(self.DATABASE):
            logging.info('Database file was found')
        else:
            logging.info('Database file was not found, will create ')
        
        sql = []
        sql.append("""
            CREATE TABLE IF NOT EXISTS time_entries (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                starttime TIMESTAMP NOT NULL,
                endtime TIMESTAMP NOT NULL,
                user_id INTEGER NOT NULL,
                activity TEXT,
                catrgory_id INTEGER,
                client_id INTEGER,
                lock BOOLEAN
            )
        """)

        sql.append("""
            CREATE TABLE IF NOT EXISTS active_events (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                starttime TIMESTAMP NOT NULL,
                user_id INT NOT NULL
            )
        """)

        sql.append("""
            CREATE TABLE IF NOT EXISTS users (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                name TEXT NOT NULL,
                worktime INT,
                worktime_span INT
            )
        """)

        sql.append("""
            CREATE TABLE IF NOT EXISTS clients (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                name TEXT NOT NULL
            )
        """)

        sql.append("""
            CREATE TABLE IF NOT EXISTS categories (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                name TEXT NOT NULL
            )
        """)

        connect = sqlite3.connect(self.DATABASE)
        cursor = connect.cursor()
        logging.debug('Create initial database tables')
        for SQL in sql:
            try:
                cursor.execute(SQL)
            except:
                logging.error('Table could not be created')
                logging.debug(SQL)
                print('TimeTrack wird beendet: Fehler bei Datanbank Setup')
                quit()
            else:
                logging.debug('Table was created successfully or already exists')
        
        connect.commit()
        connect.close()

    ### Loads or creates a config file
    def load_config(self):
        if os.path.isfile(self.CONFIG):
            logging.info('Config file was found')
            try:
                with open(self.CONFIG) as config_data:
                    data = json.load(config_data)
            except ValueError:
                logging.error('Config file has no valid JSON syntax')
                print('TimeTrack wird beendet: Fehler in der JSON-Konfig ({})'.format(self.CONFIG))
                quit()
            else:
                logging.info('Config file was loaded successfully')
                self.USERID = data['user']
                self.OLDEVENT = data['oldevent']
                logging.debug('UserID {} was used'.format(data['user']))
                self.set_user()

        else:
            logging.warning('Config file not found')
            config = {
                'default' : 'interactive',
                'user' : 1,
                'oldevent' : 2
            }
            with open(self.CONFIG, "w") as outfile:
                json.dump(config, outfile, indent=4, sort_keys=True)
                logging.info('Config file created successfully')

            #> wenn man keine datei erstellen darf/kann, fällt das skript in einen loop ?
            self.load_config()

    ## user handling
    ### Creates a user who does not yet exist
    def create_user(self, USER=''):
        if USER == '':
            username = input('Benutzername eingaben: ')
            logging.debug('Selected username: {}'.format(username))
        else:
            username = USER

        while self.get_users(NAME=username):
            print('Der gewünsche Benutzername ({}) ist schon vergeben'.format(username))
            username = input('Wähle einen anderen Benutzernamen: ')
            logging.debug('Try again: Selected username: {}'.format(username))

        logging.debug('Accepted username: {}'.format(username))

        connect = sqlite3.connect(self.DATABASE)
        cursor = connect.cursor()

        sql = "INSERT INTO users ( name ) values ( ? )"

        try:
            cursor.execute(sql, [username])
        except:
            logging.error('User could not be saved in database')
            logging.debug(sql)
        else:
            logging.info('User was saved successfully')
            connect.commit()
        
        connect.close()

    ### Outputs existing users from the DB
    def get_users(self, UID=0, NAME=''):
        if not UID == 0:
            logging.debug('Get user by ID: {}'.format(UID))
            data = UID
            sql = "SELECT * FROM users WHERE id = ?"
        elif not NAME == '':
            logging.debug('Get user by username: {}'.format(NAME))
            data = NAME
            sql = "SELECT * FROM users WHERE name LIKE ?"
        else:
            logging.debug('Get all users')
            data = ''
            sql = "SELECT * FROM users"
        
        connect = sqlite3.connect(self.DATABASE)
        cursor = connect.cursor()

        try:
            if data:
                cursor.execute(sql, [data])
            else:
                cursor.execute(sql)
        except:
            logging.error('Could not get user')
            logging.debug(sql)
            print('Fehler beim Zugriff auf die Benutzer Datenbank')
            return 1
        else:
            logging.debug('User database read out successfully')
            connect.commit()

        data = cursor.fetchall()
        connect.close()
        return data

    ### Defines a user for the session
    def set_user(self):
        data = self.get_users()
        if not data: 
            logging.info("No user was found")
            print("Es wurde kein Benutzer gefunden, bitte legen sie einen neuen an.")
            self.create_user()
        
        data = self.get_users(UID=self.USERID)
        if data == []:
            logging.error('User ID was not found')
        else: 
            self.USERNAME = data[0][1]

    ## Time handling
    ### Creates an active event if none exists for the user
    def save_event(self, TIME=datetime.datetime.now()):
        if not self.get_event(USERID=self.USERID):
            logging.debug('No active events found for the user: {}'.format(self.USERID))
            connect = sqlite3.connect(self.DATABASE)
            cursor = connect.cursor()
            sql = "INSERT INTO active_events ( starttime, user_id ) VALUES ( ?, ? )"

            try:
                cursor.execute(sql, [TIME, self.USERID])
            except:
                logging.error('Event could not be created')
                logging.debug(sql)
                print('Event konnte nicht gespeichert werden.')
                return False
            else:
                logging.info('Event was created successfully')
                connect.commit()
            
            connect.close()
            return True
        else:
            logging.warning('Active events found for the user, new event could not be created')
            return False

    ### Deletes an active event based on a user or event ID
    def delete_event(self, ENTRYID='', USERID=''):
        if not ENTRYID == '':
            logging.info('Deletes event based on eventid: {}'.format(ENTRYID))
            sql = "DELETE FROM active_events WHERE id = ?"
            data = ENTRYID
        elif not USERID == '':
            logging.info('Deletes events based on userid: {}'.format(USERID))
            sql = "DELETE FROM active_events WHERE user_id = ?"
            data = USERID
        else:
            logging.warning('No indication of what should be deleted')
            print('Keine angabe was gelöscht werden soll')
            return 0

        connect = sqlite3.connect(self.DATABASE, detect_types=sqlite3.PARSE_DECLTYPES | sqlite3.PARSE_COLNAMES)
        cursor = connect.cursor()

        try:
            cursor.execute(sql, [data])
        except:
            logging.error('Event could not be deleted')
            logging.debug(sql)
            print('Fehler beim löschen des Events.')
        else:
            logging.debug('Event was successfully deleted')
            connect.commit()
        
        connect.close()

    ### Get an active event based on a user or event ID
    def get_event(self, ENTRYID='', USERID=''):
        if not ENTRYID == '':
            logging.debug('Search event based on eventid: {}'.format(ENTRYID))
            sql = "SELECT * FROM active_events WHERE id = ?"
            data = ENTRYID
        elif not USERID == '':
            logging.debug('Search events based on userid: {}'.format(USERID))
            sql = "SELECT * FROM active_events WHERE user_id = ?"
            data = USERID
        else:
            sql = "SELECT * FROM active_events"
            data = ''
            
        connect = sqlite3.connect(self.DATABASE, detect_types=sqlite3.PARSE_DECLTYPES | sqlite3.PARSE_COLNAMES)
        cursor = connect.cursor()
        try:
            if data:
                logging.debug('Search event')
                cursor.execute(sql, [data])
            else:
                logging.debug('Get all Events')
                cursor.execute(sql)
        except:
            logging.error('Events could not be read')
            logging.debug(sql)
            print('Fehler beim auslesen der aktiven Events')
        else:
            logging.debug('Events could be read out successfully')
            data = cursor.fetchall()
            connect.close()
            if data == []:
                logging.debug('No active events found')
                return 0
            else:
                logging.debug('{} events found'.format(len(data)))
                return data[0]

    def time_start(self, AUTOFORWARD=True):
        self.clear_screen()
        starttime = datetime.datetime.now()
        logging.debug('New Event process started at {}'.format(starttime))
        if self.save_event(starttime):
            print('Neues Event gestartet um {}'.format(starttime.strftime("%H:%M")))
            if AUTOFORWARD:
                self.time_stop()
        else:
            data = self.get_event(USERID=self.USERID)
            print('Es existiert bereits ein aktives Event.')
            if (data[1] + datetime.timedelta(hours=self.OLDEVENT)) <= datetime.datetime.now():
                logging.info('Event exceeds allowed duration')
                print('Zeiteintrag ist zu alt laut den Einstellungen (älter {} Stunden)'.format(self.OLDEVENT))

                if datetime.date.today() == data[1].date():
                    print('Start um: {}'.format(data[1].strftime("%H:%M")))
                else:
                    print('Start am: {}'.format(data[1].strftime("%d.%m.%Y um %H:%M")))
                
                elapsed = datetime.datetime.now() - data[1]
                if elapsed.days:
                    logging.debug('Event older than 1 day ({} days)'.format(elapsed.days))
                    print('Vergangene Zeit: >{} Tage'.format(elapsed.days))
                else:
                    logging.debug('Event younger than 1 day')
                    print('Vergangene Zeit: >{} Stunden'.format(int(elapsed.seconds/3600)))

                userinput = ''
                while True:
                    if userinput == "F" or userinput == "f" or userinput == "1" \
                        or userinput == "L" or userinput == "l" or userinput == "2" \
                        or userinput == "A" or userinput == "a" or userinput == "3":
                        break
                    print('Soll das Event fortgesetzt oder gelöscht werden?')
                    print('[1/F/f] für fortsetzen')
                    print('[2/L/l] für löschen')
                    print('[3/A/a] für abbrechen')
                    userinput = input('Aktion: ')
                    logging.debug('User input: {}'.format(userinput))
                    self.clear_screen()

                if userinput == "F" or userinput == "f" or userinput == "1":
                    logging.debug('Event should be continued')
                    self.time_stop()
                elif userinput == "L" or userinput == "l" or userinput == "2":
                    logging.info('Event should be deleted (eventid: {})'.format(data[0]))
                    self.delete_event(data[0])
                    self.time_start()
                else:
                    logging.debug('Terminated by the user')
                    exit()
            
            else:
                logging.debug('Event continues (eventid{})'.format(data[0]))
                print('Event von {} Uhr geladen'.format(data[1].strftime("%H:%M")))
                self.time_stop()

    def time_stop(self):
        data = self.get_event(USERID=self.USERID)
        logging.debug('Event stop progess is started')
        if data:
            self.clear_screen()
            userinput = ''
            while True:
                if userinput == "B" or userinput == "b" or userinput == "1" \
                    or userinput == "L" or userinput == "l" or userinput == "2" \
                    or userinput == "A" or userinput == "a" or userinput == "3":
                    break
                print('Event von {} Uhr beenden?'.format(data[1].strftime("%H:%M")))
                print('[1/B/b] für beenden')
                print('[2/L/l] für löschen')
                print('[3/A/a] für abbrechen')
                userinput = input('Aktion: ')
                logging.debug('User input: {}'.format(userinput))
                self.clear_screen()

            if userinput == "B" or userinput == "b" or userinput == "1":
                logging.debug('Event is ended')
                print('Eingabe beenden mittels doppelter Leerzeile.')
                print('Durchgeführte Tätigkeiten:')
                userinput = []
                while True:
                    try:
                        if userinput[-1] == '' and userinput[-2] == '':
                            break
                    except IndexError:
                        pass
                    userinput.append(input())
                
                logging.debug('User input: {}'.format(userinput))
                del userinput[-1]
                del userinput[-1]
                action = ''
                for i in userinput:
                    if not action == '':
                        action += "\n"
                    action += i

                endtime = datetime.datetime.now()
                logging.debug('Event end process start at {}'.format(endtime))
                connect = sqlite3.connect(self.DATABASE)
                cursor = connect.cursor()
                sql = "INSERT INTO time_entries ( starttime, endtime, user_id, activity ) VALUES ( ?, ?, ?, ? )"

                try:
                    cursor.execute(sql, [data[1], endtime, self.USERID, action])
                except:
                    logging.error('Time entry could not be created')
                    logging.debug(sql)
                    print('Zeiteintrag konnte nicht gespeichert werden.')
                    return False
                else:
                    logging.info('Time entry was created successfully')
                    connect.commit()
                    self.delete_event(data[0])
                    self.print_time_entry(STARTTIME=data[1], ENDTIME=endtime, ACTIVITY=action)
                    print('Zeiteintrag wurde gespeichert.')
                    while True:
                        if userinput == "J" or userinput == "j" or userinput == "1" \
                            or userinput == "N" or userinput == "n" or userinput == "2":
                            break
                        print('Nächsten Zeiteintrag begrinnen ?')
                        print('[1/J/j] Ja')
                        print('[2/N/n] Nein')
                        userinput = input('Aktion: ')
                        logging.debug('User input: {}'.format(userinput))
                        self.clear_screen()

                    if userinput == "J" or userinput == "j" or userinput == "1":
                        self.time_start()
                    else:
                        logging.debug('Terminated by the user')
                        exit()
                    
                
                connect.close()

            elif userinput == "L" or userinput == "l" or userinput == "2":
                logging.info('Event should be deleted (eventid: {})'.format(data[0]))
                self.delete_event(data[0])
            else:
                logging.debug('Terminated by the user')
                exit()

    def get_time(self):
        pass

    def print_time_entry(self, STARTTIME='', ENDTIME='', ACTIVITY=''):
        s = (ENDTIME - STARTTIME).seconds
        hours, remainder = divmod(s, 3600)
        minutes, seconds = divmod(remainder, 60)
        
        print(50*"-")
        print('Start: {} Uhr'.format(STARTTIME.strftime('%H:%M')))
        print('Ende: {} Uhr'.format(ENDTIME.strftime('%H:%M')))
        print('Dauer: {:02}:{:02}:{:02}'.format(int(hours), int(minutes), int(seconds)))
        if not ACTIVITY == '':
            print('Aktivität:')
            print(ACTIVITY)
        print(50*"-")

test = TimeTrack()
test.time_start()