import sqlite3
import os

class DataStore:
    def __init__(self, timedbfile):
        if not os.path.exists(timedbfile):
            self.createdb(timedbfile)
        self.conn = sqlite3.connect(dbfile)

    def __del__(self):
        self.conn.close()

    def createdb(self, dbfile):
        conn = sqlite3.connect(dbfile)
        c = conn.cursor()
        c.execute('''
CREATE TABLE tasks (
    id INTEGER PRIMARY KEY,
    name TEXT,
    longname TEXT,
    parentid INTEGER,
    FOREIGN KEY (parentid) REFERENCES tasks(id)
)''')
        c.execute('''
CREATE TABLE entries (
    date INTEGER PRIMARY KEY,
    taskid INTEGER,
    hours REAL,
    FOREIGN KEY (taskid) REFERENCES tasks(id)
)''')
        c.execute('''
CREATE TABLE history (
    id INTEGER PRIMARY KEY,
    taskid INTEGER,
    FOREIGN KEY (taskid) REFERENCES tasks(id)
)''')
        conn.commit()
        c.close()
        conn.close()