#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import datetime, os, sys, smtplib, subprocess, time, tempfile, email.utils
from email.mime.multipart import MIMEMultipart
from email.mime.application import MIMEApplication
from email.mime.text import MIMEText
from email.header import Header
from dbhelper import DB
from mailhelper import MAIL

from config import *

db = DB()
mail = MAIL(SMTPSERVERNAME, SMTPSERVERPORT, SMTPSERVERUSER, SMTPSERVERPASS)

if sys.hexversion < 0x03000000:
	print("Please use Python 3.0 or newer!")
	sys.exit()

def get_timespan(type, timestamp = time.time()):
	requested = datetime.datetime.fromtimestamp(timestamp)

	if type == "previous day":
		# previous day, day from 08:00 - 7:59
		stop  = requested.replace(hour = 8, minute = 0, second = 0) - datetime.timedelta(seconds = 1)
		start = requested.replace(hour = 8, minute = 0, second = 0) - datetime.timedelta(days = 1)
		if stop > requested:
			stop  -= datetime.timedelta(days = 1)
			start -= datetime.timedelta(days = 1)
		return (start, stop)
	elif type == "previous month":
		# previous month, day from 00:00 - 23:59
		stop  = requested.replace(hour = 0, minute = 0, second = 0, day = 1) - datetime.timedelta(seconds = 1)
		start = stop.replace(day = 1, hour = 0, minute = 0, second = 0)
		return (start, stop)
	elif type == "current month":
		# current month, day from 00:00 - 23:59
		if requested.month == 12:
			stop = requested.replace(month = 0, year = requested.year + 1)
		else:
			stop = requested.replace(month = requested.month + 1)
		stop  = stop.replace(day = 1, hour = 0, minute = 0, second = 0) - datetime.timedelta(seconds = 1)
		start = requested.replace(day = 1, hour = 0, minute = 0, second = 0)
		return (start, stop)
	else:
		return None

def generate_pdf(data):
	rubber = subprocess.Popen("rubber-pipe -d", shell=True, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
	pdf, stderr = rubber.communicate(input=data.encode('utf-8'))
	return pdf

def generate_invoice_tex(user, title, subject, start=0, stop=0, temporary=False):
	userinfo = db.get_user_info(user)

	result = "\\documentclass[ktt-template,12pt,pagesize=auto,enlargefirstpage=on,paper=a4]{scrlttr2}\n\n"
	result+= "\\title{%s}\n" % title
	result+= "\\author{Kreativität trifft Technik}\n"
	result+= "\\date{\\today}\n\n"

	result+= "\\setkomavar{subject}{%s}\n" % subject
	result+= "\\setkomavar{toname}{%s %s}\n" % (userinfo["firstname"], userinfo["lastname"])
	result+= "\\setkomavar{toaddress}{%s\\newline\\newline\\textbf{%d %s}}\n\n" % (userinfo["street"], userinfo["plz"], userinfo["city"])

	result+= "\\begin{document}\n"
	result+= "\t\\begin{letter}{}\n"

	if userinfo["gender"] == "masculinum":
		result+= "\t\t\\opening{Sehr geehrter Herr %s,}\n\n" % userinfo["lastname"]
	elif userinfo["gender"] == "femininum":
		result+= "\t\t\\opening{Sehr geehrte Frau %s,}\n\n" % userinfo["lastname"]
	else:
		result+= "\t\t\\opening{Sehr geehrte/r Frau/Herr %s,}\n\n" % userinfo["lastname"]

	result+= "\t\twir erlauben uns, Ihnen für den Verzehr von Speisen und Getränken wie folgt zu berechnen:\n\n"

	result += "\t\t\\begin{footnotesize}\n"
	result += "\t\t\t\\begin{longtable}{|p{2cm}|p{1.8cm}|p{5cm}|p{2cm}|}\n"
	result += "\t\t\t\t\\hline\n"
	result += "\t\t\t\t\\textbf{Datum} & \\textbf{Uhrzeit}	& \\textbf{Artikel} & \\textbf{Preis}\\\\\n"
	result += "\t\t\t\t\\hline\n"
	result += "\\endhead\n"
	result += "\t\t\t\t\\hline\n"
	result += "\\endfoot\n"

	lastdate = ""
	total = 0
	for row in db.get_invoice_data(user, start, stop):
		total += row["price"]

		row["product"] = row["product"].replace("&", "\\&")

		if lastdate != row["date"]:
			result += "\t\t\t\t%s\t& %s\t& %s\t& \\EUR{%d,%02d}\\\\\n" % (row["date"], row["time"], row["product"], row["price"] / 100, row["price"] % 100)
			lastdate = row["date"]
		else:
			result += "\t\t\t\t%s\t& %s\t& %s\t& \\EUR{%d,%02d}\\\\\n" % ("           ", row["time"], row["product"], row["price"] / 100, row["price"] % 100)

	result += "\t\t\t\t\\hline\n"
	result += "\t\t\t\t\\multicolumn{3}{|l|}{Summe:} & \\EUR{%d,%02d}\\\\\n" % (total / 100, total % 100)
	result += "\t\t\t\\end{longtable}\n"
	result += "\t\t\\end{footnotesize}\n\n"

	result += "\t\tUmsatzsteuer wird nicht erhoben, da Kreativität trifft Technik e.V. als Kleinunternehmen\n"
	result += "\t\tder Regelung des § 19 Abs. 1 UStG unterfällt.\n\n"

	if temporary is True:
		result += "\t\tBei dieser Abrechnung handelt es sich lediglich um einen Zwischenstand. Die\n"
		result += "\t\tHauptrechnung wird einmal monatlich getrennt zugestellt und der Gesamtbetrag\n"
		result += "\t\twird dann vom angegebenen Bankkonto eingezogen.\n\n"
	else:
		result += "\t\tDer Gesamtbetrag wird in 10 Tagen von dem angegebenen Bankkonto\n"
		result += "\t\teingezogen.\n\n"

	result += "\t\t\\closing{Mit freundlichen Grüßen}\n\n"

	result += "\t\\end{letter}\n"
	result += "\\end{document}"

	return result

def generate_invoice_text(user, title, subject, start=0, stop=0, temporary=False):
	userinfo = db.get_user_info(user)
	result = ""

	if userinfo["gender"] == "masculinum":
		result+= "Sehr geehrter Herr %s,\n\n" % userinfo["lastname"]
	elif userinfo["gender"] == "femininum":
		result+= "Sehr geehrte Frau %s,\n\n" % userinfo["lastname"]
	else:
		result+= "Sehr geehrte/r Frau/Herr %s,\n\n" % userinfo["lastname"]

	result+= "wir erlauben uns, Ihnen für den Verzehr von Speisen und Getränken wie folgt zu berechnen:\n\n"

	lastdate = ""
	total = 0
	namelength = 0
	for row in db.get_invoice_data(user, start, stop):
		if len(row["product"]) > namelength:
			namelength = len(row["product"])

	result += " +------------+----------+-" + namelength * "-" + "-+----------+\n"
	result += " | Datum      | Uhrzeit  | Artikel" + (namelength - len("Artikel")) * " " + " | Preis    |\n"
	result += " +------------+----------+-" + namelength * "-" + "-+----------+\n"
	for row in db.get_invoice_data(user, start, stop):
		total += row["price"]

		if lastdate != row["date"]:
			result += " | %s | %s | %s | %3d,%02d € |\n" % (row["date"], row["time"], row["product"] + (namelength - len(row["product"])) * " ", row["price"] / 100, row["price"] % 100)
			lastdate = row["date"]
		else:
			result += " | %s | %s | %s | %3d,%02d € |\n" % ("          ", row["time"], row["product"] + (namelength - len(row["product"])) * " ", row["price"] / 100, row["price"] % 100)
	result += " +------------+----------+-" + namelength * "-" + "-+----------+\n"
	result += " | Summe:                  " + namelength * " " + " | %3d,%02d € |\n" % (total / 100, total % 100)
	result += " +-------------------------" + namelength * "-" + "-+----------+\n\n"

	result += "Umsatzsteuer wird nicht erhoben, da Kreativität trifft Technik e.V. als Kleinunternehmen\n"
	result += "der Regelung des § 19 Abs. 1 UStG unterfällt.\n\n"

	if temporary is True:
		result += "Bei dieser Abrechnung handelt es sich lediglich um einen Zwischenstand. Die\n"
		result += "Hauptrechnung wird einmal monatlich getrennt zugestellt und der Gesamtbetrag\n"
		result += "wird dann vom angegebenen Bankkonto eingezogen.\n\n"
	else:
		result += "Der Gesamtbetrag wird in 10 Tagen von dem angegebenen Bankkonto\n"
		result += "eingezogen.\n\n"

	return result

def daily(timestamp = time.time()):
	# timestamps for previous day
	dstart, dstop = get_timespan("previous day", timestamp)
	stop  = int(dstop.strftime("%s"))
	start = int(dstart.strftime("%s"))

	title = "Getränkerechnung %04d-%02d-%02d" % (dstart.year, dstart.month, dstart.day)
	subject = "Getränke-Zwischenstand %02d.%02d.%04d %02d:%02d Uhr bis %02d.%02d.%04d %02d:%02d Uhr" % (dstart.day, dstart.month, dstart.year, dstart.hour, dstart.minute, dstop.day, dstop.month, dstop.year, dstop.hour, dstop.minute)

	for user in db.get_users_with_purchases(start, stop):
		userinfo = db.get_user_info(user)
		if userinfo is not None:
			receiver = "%s %s <%s>" % (userinfo["firstname"], userinfo["lastname"], userinfo["email"])
			msg  = generate_invoice_text(user, title, subject, start, stop, True)
			mail = mail.generate_mail(receiver, title, msg, None, timestamp)
			mail.send_mail(mail, userinfo["email"])
		else:
			print("Can't send invoice for missing user with the following id:", user)

def monthly(timestamp = time.time()):
	# timestamps for previous month
	dstart, dstop = get_timespan("previous month", timestamp)
	stop   = int(dstop.strftime("%s"))
	start  = int(dstart.strftime("%s"))

	title = "Getränkerechnung %04d/%02d" % (dstart.year, dstart.month)
	number = 0

	invoices = {}
	invoicedata = []

	for user in db.get_users_with_purchases(start, stop):
		number += 1
		subject = "Rechnung Nr. %04d%02d5%03d" % (dstart.year, dstart.month, number)
		userinfo = db.get_user_info(user)
		if userinfo is not None:
			receiver = "%s %s <%s>" % (userinfo["firstname"], userinfo["lastname"], userinfo["email"])
			tex  = generate_invoice_tex(user, title, subject, start, stop, False)
			msg  = generate_invoice_text(user, title, subject, start, stop, False)
			pdf  = generate_pdf(tex)
			invoices["%04d%02d5%03d_%s_%s.pdf" % (dstart.year, dstart.month, number, userinfo["firstname"], userinfo["lastname"])] = pdf
			amount = db.get_invoice_amount(user, start, stop)
			invoicedata.append({"userid": user, "lastname": userinfo["lastname"], "firstname": userinfo["firstname"], "invoiceid": "%04d%02d5%03d" % (dstart.year, dstart.month, number), "amount": amount})
			mail = mail.generate_mail(receiver, title, msg, pdf, timestamp)
			mail.send_mail(mail, userinfo["email"])
			print("Sent invoice to", userinfo["firstname"], userinfo["lastname"])
		else:
			print("Can't send invoice for missing user with the following id:", user)

	csvinvoicedata = ""
	for entry in invoicedata:
		csvinvoicedata += "%d,%s,%s,%s,%d.%02d\n" % (entry["userid"], entry["lastname"], entry["firstname"], entry["invoiceid"], entry["amount"] / 100, entry["amount"] % 100)
	invoices["invoicedata.csv"] = csvinvoicedata

	mail = mail.generate_mail("Schatzmeister <schatzmeister@kreativitaet-trifft-technik.de>",
		"Rechnungen %04d%02d" % (dstart.year, dstart.month),
		None, invoices, timestamp)
	mail.send_mail(mail, "schatzmeister@kreativitaet-trifft-technik.de")

def backup():
	timestamp = time.time()
	dt = datetime.datetime.fromtimestamp(timestamp)

	msg = MIMEMultipart()
	msg["From"] = "KtT-Shopsystem <shop@kreativitaet-trifft-technik.de>"
	msg["Date"] = email.utils.formatdate(timestamp, True)
	msg["To"]   = "KtT-Shopsystem Backups <shop-backup@kreativitaet-trifft-technik.de>"
	msg["Subject"] = "Backup KtT-Shopsystem %04d-%02d-%02d %02d:%02d" % (dt.year, dt.month, dt.day, dt.hour, dt.minute)
	msg.preamble = "Please use a MIME aware email client!"

	msg.attach(MIMEText("You can find a backup of 'shop.db' attached to this mail.", 'plain', 'utf-8'))

	dbfile = open('shop.db', 'rb')
	attachment = MIMEApplication(dbfile.read())
	attachment.add_header('Content-Disposition', 'attachment', filename = 'shop.db')
	msg.attach(attachment)
	dbfile.close()

	mail.send_mail(msg, "shop-backup@kreativitaet-trifft-technik.de")

if sys.argv[1] == "daily":
	daily()
	backup()
elif sys.argv[1] == "monthly":
	monthly()
else:
	print("not supported!")