import sqlite3

class Session:

    def __init__(self, db_agent):
        self.user = -1
        self.db_agent = db_agent
        self.resultstring = 'no results yet'
        self.commands = {'a': (self.set_user, 'Set an active user\n   Usage: a number_of_user'),
                         'c': (self.show_composers, 'Shows composers'),
                         'h': (self.show_help, 'Displays this help document'),
                         'm': (self.mark_work_as_mastered, 'Marks work or movement as mastered for the active user\n   Usage: m number_of_work, m number_of_work number_of_movement'),
                         'n': (self.create_new_user, 'Creates new user\n   Usage: n firstname name'),
                         's': (self.show_works, 'Show the works stored in the database\n   Usage: s, s number_of_composer'),
                         'sw': (self.show_movements, 'Show movements of a work\n   Usage: sw work_number'),
                         'su': (self.show_users, 'Show all users'),
                         'q': (self.quit, 'Quits the program')
                        }

    def set_user(self, arguments):
        db_index = arguments[0]
        self.user = db_index
        return 'User set'

    def get_active_user(self):
        sql_command = f'''
                      SELECT first_name, sec_name
                      FROM pianist
                      WHERE id = {self.user}
                      '''
        active_user = ''
        try:
            first_name, name = self.db_agent.execute(sql_command).fetchone()
            active_user = f'{first_name} {name}'
        except:
            active_user = 'No active user'
        return active_user

    def invoke_command(self, command, arguments):
        self.resultstring = ''
        if command in self.commands.keys():
            self.resultstring += self.commands[command][0](arguments)
        else:
            self.resultstring += 'Could not understand command.'

    def result(self):
        return self.resultstring
    
    def create_new_user(self, arguments):
        first_name, name = arguments[0], arguments[1]
        sql_command = f'''
                      INSERT INTO pianist (first_name, sec_name)
                      VALUES ("{first_name}", "{name}");
                      '''
        self.db_agent.execute(sql_command)
        return f'Created new user {first_name} {name}.'

    def show_composers(self, _):
        sql_command = '''
                      SELECT id, first_name, name
                      FROM composer
                      ORDER BY name
                      '''
        result_list = self.db_agent.execute(sql_command).fetchall()
        fun_resultstring = ''
        for item in result_list:
            fun_resultstring += f'{item[0]}: {item[2]}, {item[1]}\n'
        return fun_resultstring

    def show_help(self, arguments):
        fun_resultstring = ''
        if len(arguments) > 0:
            qu_com = arguments[0]
            if qu_com in self.commands:
                fun_resultstring += f'{qu_com}: {self.commands[qu_com][1]}'
            else:
                fun_resultstring += f'Command {qu_com} not known, for help press h'
        else:
            for key, value in self.commands.items():
                fun_resultstring += f'{key}: {value[1]}\n'
        return fun_resultstring

    def show_movements(self, arguments):
        work_id = arguments[0]
        work = work_under_id(work_id, self.db_agent)
        fun_resultstring = ''
        for mov_number in work.values['movements'].keys():
            fun_resultstring += f'{mov_number}. {work.pretty_mov(mov_number)}\n'
        return fun_resultstring

    def show_users(self, _):
        sql_command = '''
                      SELECT * FROM pianist;
                      '''
        result_list = self.db_agent.execute(sql_command).fetchall()
        fun_resultstring = ''
        for item in result_list:
            fun_resultstring += f'{item[0]}: {item[1]} {item[2]}\n'
        return fun_resultstring

    def show_works(self, arguments):
        if len(arguments) > 0: 
            restraint = f'comp_id = {arguments[0]}'
        else:
            restraint = '1 = 1'
        sql_command = f'''
                      SELECT id
                      FROM work
                      WHERE {restraint} 
                      '''
        list_of_work_ids = self.db_agent.execute(sql_command).fetchall()
        # GET WORKS OUT!
        list_of_works = list()
        for item in list_of_work_ids:
            list_of_works.append(work_under_id(item[0], self.db_agent))
        fun_resultstring = ''
        for work in list_of_works:
            fun_resultstring += f'{work.id()}: {work.pretty_string()}\n'
        return fun_resultstring

    def mark_work_as_mastered(self, arguments):
        work_id = arguments[0]
        resultstring = 'adding:\n'
        work = work_under_id(work_id, self.db_agent)
        if len(arguments) > 1:
            mov_number = int(arguments[1])
            sql_command = f'''
                          INSERT INTO is_able_to_play (work_id, mov_id, pianist_id)
                          VALUES ({work_id}, {mov_number}, {self.user})
                          '''
            self.db_agent.execute(sql_command)
            resultstring += f'{work.pretty_mov(mov_number)}\n'
        else:
            for mov_number in work.values['movements'].keys():
                sql_command = f'''
                              INSERT INTO is_able_to_play (work_id, mov_id, pianist_id)
                              VALUES ({work_id}, {mov_number}, {self.user})
                              '''
                self.db_agent.execute(sql_command)
                resultstring += f'{work.pretty_mov(mov_number)}\n'
        return resultstring

    def quit(self, _):
        return 'Bye bye!'

# End session

class work_under_id:
    # con = sqlite3.connect('repertoire.db')
    # reader = con.cursor()

    def __init__(self, werk_id, db_agent):
        self.values = dict()
        self.reader = db_agent
        
        sql_wui = f"""
                  SELECT *
                  FROM work
                  WHERE id = {werk_id}
                  """
        werk_list_val = self.reader.execute(sql_wui).fetchone()
        werk_list_att = ('id', 'comp_id', 'year', 'opus', 'collection', 'main_key', 'title', 'mov_title', 'alias', 'work_directory', 'wd_number')                         
        for tup in zip(werk_list_att, werk_list_val):
            self.values[tup[0]] = tup[1]

        sql_comp = f"""
                   SELECT first_name, name
                   FROM composer
                   WHERE id = {self.values['comp_id']}
                   """
        werk_comp = self.reader.execute(sql_comp).fetchone()
        self.values['first_name'] = werk_comp[0]
        self.values['name'] = werk_comp[1]

        sql_suw = f"""
                  SELECT *
                  FROM movement
                  WHERE work_id = {werk_id}
                  """
        saetze = dict()
        nummern = set()
        suw_liste = self.reader.execute(sql_suw).fetchall()
        # 0 work_id, 1 mov_number, 2 numb, 3 designation, 4 mus_key, 5 recording
        for satz in suw_liste:
            saetze[satz[1]] = satz[2], satz[3], satz[4]
            if not satz[2] is None:
                nummern.add(satz[2])
        self.values['movements'] = saetze
        if len(nummern) == 1:
            self.sätze_unter_nummer = True
            self.values['numb'] = nummern.pop()
        else:
            self.sätze_unter_nummer = False

    def sammlung(self):
        sammlung = self.values['collection']
        if not sammlung:
            return 'ohne'
        else:
            return sammlung

    def id(self):
        return self.values['id']

    def pretty_string(self):
        ret_str = ''
        for key in ['first_name', 'name',
                    'title', 'opus',
                    'main_key', 'alias',
                    'work_directory','wd_number']:
            if not self.values[key] is None:
                if key == 'opus':
                    ret_str += f'op. {self.values[key]} '
                else:
                    ret_str += f'{self.values[key]} '
        return ret_str

    def pretty_mov(self, mov_number):
        ret_str = ''
        for key in ['first_name', 'name',
                    'title', 'mov_title', 'opus', 'numb',
                    'main_key', 'alias',
                    'movements',
                    'work_directory','wd_number']:
            if key in self.values.keys() and not self.values[key] is None:
                if key == 'opus':
                    ret_str += f'op. {self.values[key]} '
                elif key == 'name':
                    ret_str += f'{self.values[key]}, '
                elif key == 'numb':
                    ret_str += f'Nr. {self.values[key]} '
                elif key == 'movements':
                    if self.values[key][mov_number][1] is None:
                        ret_str += ''
                    else:
                        if len(self.values[key]) > 1:
                            ret_str += f'{mov_number}. {self.values[key][mov_number][1]} '
                        else:
                            ret_str += f'{self.values[key][mov_number][1]} '
                elif key == 'title':
                    if self.values['mov_title'] is None:
                        ret_str += f'{self.values[key]} '
                else:
                    ret_str += f'{self.values[key]} '
        return ret_str

    def __str__(self):
        ret_str = ''
        for key, value in self.values.items():
            if not value is None:
                ret_str += f'{key}: {value}\n'
        return ret_str

# End work_under_id

def parse_user_input(user_in, session):
    split_user_in = user_in.split()
    command = split_user_in[0]
    if command in session.commands.keys():
        arguments = split_user_in[1:]
        return (command, arguments)
    else:
        return (None, None)

def command_line_loop(session):
    user_in = ''
    while not user_in == 'q':
        user_in = input(f'Piano-Repertoire: {session.get_active_user()} >>> ')
        command, arguments = parse_user_input(user_in, session)
        session.invoke_command(command, arguments)
        print(session.result())

def main():
    con = sqlite3.connect('repertoire.db')
    db_agent = con.cursor()
    session = Session(db_agent)
    command_line_loop(session)
    con.commit()
    print('changes committed.')
    con.close()
    print('db-connection closed. Bye-bye!')

if __name__ == '__main__':
    main()