#!/bin/python3
#########################
#
# timeTrack.py
# by 4nima
# v.0.2
#
#########################
# 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.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
    ### 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 DATETIME NOT NULL,
                endtime DATETIME 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 DATETIME 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']
                logging.debug('UserID {} was used'.format(data['user']))
                self.set_user()

        else:
            logging.warning('Config file not found')
            config = {
                'user' : 1,
                'default' : 'interactive'
            }
            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()

        row = cursor.fetchall()
        output = []
        for data in row:
            output.append(data)
        connect.close()
        return output

    ### 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)
        try:
            self.USERNAME = data[0][1]
        except IndexError:
            logging.error('User ID was not found')

test = TimeTrack()