from datetime import datetime
from flask import Flask
from flask import render_template
from flask import request, redirect, g
from flask import url_for
import os.path
import time

import db


#from db import Db
app = Flask(__name__)
DATABASE = '/data/rollerverbrauch.db'
DEBUG = True
SECRET_KEY = 'development key'
USERNAME = 'admin'
PASSWORD = 'default'
app.config.from_object(__name__)

@app.before_request
def before_request():
    g.db2 = db.Db(app.config['DATABASE'])
    g.data = {}
    add_service_warning(g.data)

@app.teardown_request
def teardown_request(exception):
    pass

@app.route('/')
def index():
    return redirect(url_for('get_pit_stops'))

@app.route('/services')
def get_services():
    data = g.db2.getAllServices()
    data.reverse()
    g.data['services'] = data
    return render_template('services.html', data=g.data)

@app.route('/pitstops', methods=['POST'])
def create_pit_stop():
    last_pitstop = g.db2.getLastPitStop()
    errorMsg = {}
    
    date = request.form['date']
    try:
        date = datetime.strptime(date, '%Y-%m-%d').strftime('%Y-%m-%d')
    except ValueError:
        errorMsg['date'] = 'invalid date, only YYYY-MM-DD is allowed'
        date = request.form['date']
    
    odometer = request.form['odometer']
    try:
        odometer = int(odometer)
    except ValueError:
        errorMsg['odometer'] = 'Illegal Value, only Integers allowed'
        odometer = None
    if odometer is not None and odometer <= last_pitstop['odometer']:
        errorMsg['odometer'] = 'Illegal Value, new Value must be bigger as given value'
        odometer = request.form['odometer']
    if odometer is None:
        odometer = request.form['odometer']
    
    litres = request.form['litres']
    try:
        litres = float(litres)
    except ValueError:
        errorMsg['litres'] = 'Illegal Value, only floating point allowed'
        litres = None
    if litres is not None and litres <= 0:
        errorMsg['litres'] = 'Litres must not be 0'
        litres = request.form['litres']
    if litres is None:
        litres = request.form['litres']
        
    # error checking here
    if len(errorMsg) > 0:
        data = {'last': {'date': date, 'odometer': odometer, 'litres': litres}, 'error': errorMsg}
        return render_template('newPitStopForm.html', data=data)

    g.db2.addPitStop(date, odometer, litres)

    return redirect(url_for('get_pit_stops'))

@app.route('/pitstops/createForm', methods=['GET'])
def create_pit_stop_form():
    values = g.db2.getLastPitStop()
    values['date'] = time.strftime("%Y-%m-%d")
    g.data['last'] = values
    g.data['error'] = None
    return render_template('newPitStopForm.html', data=g.data)

def add_service_warning(data):
    service_info = g.db2.get_service_warning_info()
    data['service_info'] = service_info

@app.route('/pitstops', methods=['GET'])
def get_pit_stops():
    data = prepare_pit_stops(g.db2.getAllPitStops())
    g.data['pitstops'] = data
    return render_template('pitstops.html', data=g.data)

@app.route('/statistics', methods=['GET'])
def get_statistics():
    pitstops = g.db2.getAllPitStops()
    count = len(pitstops)
    distance = 0
    sumLitres = 0
    averageDistance = 0
    averageLitresFuelled = 0
    averageLitresUsed = 0
    
    if count > 0:
        sumLitres = 0
        for pitstop in pitstops:
            sumLitres += pitstop['litres']
        averageLitresFuelled = sumLitres/count
    if count > 1:
        distance = pitstops[-1]['odometer'] - pitstops[0]['odometer']
        averageDistance =  distance/(count - 1)
        averageLitresUsed = 100 * (sumLitres-pitstops[0]['litres'])/distance
    g.data['distance'] = distance
    g.data['count'] = count
    g.data['litres'] = sumLitres
    g.data['averageDistance'] = averageDistance
    g.data['averageListresFuelled'] = averageLitresFuelled
    g.data['averageListresUsed'] = averageLitresUsed
    return render_template('statistics.html', data=g.data)

def prepare_pit_stops(pitstops):
    for index in range(1, len(pitstops)):
        last = pitstops[index - 1]
        curr = pitstops[index]
        curr['distance'] = curr['odometer'] - last['odometer']
        curr['average'] = 100 * curr['litres']/curr['distance']
        last_date = datetime.strptime(last['date'], '%Y-%m-%d')
        curr_date = datetime.strptime(curr['date'], '%Y-%m-%d')
        curr['days'] = (curr_date - last_date).days
    pitstops.reverse()
    return pitstops

if __name__ == '__main__':
    if not os.path.isfile(DATABASE) or os.stat(DATABASE).st_size == 0:
        db = db.Db(app.config['DATABASE'])
        db.init_db(app.open_resource('schema.sql', mode='r'))
    app.run(debug=True, host='0.0.0.0')