#!/usr/bin/env python3

from pathlib import Path
from datetime import date, timedelta, datetime
from urllib.request import urlopen
from fints.client import FinTS3PinTanClient
import csv
import json
import sys

# --------------------------------------------------
# Konfiguration laden
# --------------------------------------------------

config = {}

config_file = Path.home() / ".ing.conf"

if not config_file.exists():
    config_file = Path(__file__).parent / ".ing.conf"

with open(config_file, encoding="utf-8") as f:
    for line in f:
        line = line.strip()

        if not line or line.startswith("#"):
            continue

        if "=" not in line:
            continue

        key, value = line.split("=", 1)
        config[key] = value

# --------------------------------------------------
# ING-Konfiguration
# --------------------------------------------------

USER = config["ING_USER"]
PIN = config["ING_PIN"]
TARGET_IBAN = config["ING_IBAN"]

# --------------------------------------------------
# ioBroker-Konfiguration
# --------------------------------------------------

IOBROKER_HOST = config["IOBROKER_HOST"]
IOBROKER_PORT = config["IOBROKER_PORT"]

IOBROKER_DP_TRANSACTIONS = config["IOBROKER_DP_TRANSACTIONS"]
IOBROKER_DP_WEEKSUM = config["IOBROKER_DP_WEEKSUM"]
IOBROKER_DP_WEEKEXPENSES = config["IOBROKER_DP_WEEKEXPENSES"]

# --------------------------------------------------
# Bank
# --------------------------------------------------

BLZ = "50010517"

# --------------------------------------------------
# Exportverzeichnis bestimmen
# --------------------------------------------------

base_dir = Path.home() / "Transaktionen"

if not base_dir.exists():
    base_dir = Path(__file__).parent / "Transaktionen"

# --------------------------------------------------
# Kalenderwoche bestimmen
# --------------------------------------------------

if len(sys.argv) == 3:

    year = int(sys.argv[1])
    week = int(sys.argv[2])

else:

    year, week, _ = datetime.now().isocalendar()

# Montag der Kalenderwoche

start_date = datetime.strptime(
    f"{year}-W{week:02d}-1",
    "%G-W%V-%u"
).date()

# Sonntag der Kalenderwoche

end_date = start_date + timedelta(days=6)
today = date.today()

if end_date > today:
    end_date = today

if start_date > today:

    print(
        "Die angeforderte Kalenderwoche liegt "
        "vollständig in der Zukunft."
    )

    sys.exit(1)

year_dir = base_dir / str(year)
csv_dir = year_dir / "csv"
json_dir = year_dir / "json"

csv_dir.mkdir(parents=True, exist_ok=True)
json_dir.mkdir(parents=True, exist_ok=True)

CSV_FILE = csv_dir / f"transactions_{year}_KW{week:02d}.csv"
JSON_FILE = json_dir / f"transactions_{year}_KW{week:02d}.json"

# --------------------------------------------------
# ING-Verbindung
# --------------------------------------------------

client = FinTS3PinTanClient(
    BLZ,
    USER,
    PIN,
    "https://fints.ing.de/fints/",
    product_id="PythonFinTS"
)

export_data = []
transactions = []

# --------------------------------------------------
# Transaktionen abrufen
# --------------------------------------------------

with client:
    account_found = False

    for account in client.get_sepa_accounts():

        if account.iban != TARGET_IBAN:
            continue

        account_found = True

        transactions = client.get_transactions(
            account,
            start_date=start_date,
            end_date=end_date
        )

        print(
            f"Lade Transaktionen für KW{week:02d}/{year}"
        )

        print(
            f"Zeitraum: {start_date} bis {end_date}"
        )

        for transaction in transactions:

            data = transaction.data
            amount = data.get("amount")

            row = {
                "date": str(data.get("date", "")),
                "amount": round(float(amount.amount), 2) if amount else 0.0,
                "posting_text": data.get("posting_text", ""),
                "applicant_name": data.get("applicant_name", ""),
                "purpose": data.get("purpose", "")
            }

            export_data.append(row)

        break

    if not account_found:
        raise RuntimeError(
            f"IBAN nicht gefunden: {TARGET_IBAN}"
        )

# --------------------------------------------------
# CSV schreiben
# --------------------------------------------------

with open(CSV_FILE, "w", newline="", encoding="utf-8") as csvfile:

    writer = csv.DictWriter(
        csvfile,
        fieldnames=[
            "date",
            "amount",
            "posting_text",
            "applicant_name",
            "purpose"
        ],
        delimiter=";"
    )

    writer.writeheader()
    writer.writerows(export_data)

# --------------------------------------------------
# JSON schreiben
# --------------------------------------------------

with open(JSON_FILE, "w", encoding="utf-8") as jsonfile:

    json.dump(
        export_data,
        jsonfile,
        ensure_ascii=False,
        indent=2
    )

# --------------------------------------------------
# Statistiken berechnen
# --------------------------------------------------

transaction_count = len(export_data)

week_sum = 0.0
week_expenses = 0.0

for transaction in transactions:

    amount = float(transaction.data["amount"].amount)

    week_sum += amount

    if amount < 0:
        week_expenses += abs(amount)

week_sum = round(week_sum, 2)
week_expenses = round(week_expenses, 2)

# --------------------------------------------------
# An ioBroker senden
# --------------------------------------------------

base_url = f"http://{IOBROKER_HOST}:{IOBROKER_PORT}/set"

urlopen(
    f"{base_url}/{IOBROKER_DP_TRANSACTIONS}"
    f"?value={transaction_count}"
).read()

urlopen(
    f"{base_url}/{IOBROKER_DP_WEEKSUM}"
    f"?value={week_sum}"
).read()

urlopen(
    f"{base_url}/{IOBROKER_DP_WEEKEXPENSES}"
    f"?value={week_expenses}"
).read()

# --------------------------------------------------
# Erfolgsmeldung
# --------------------------------------------------

print(f"CSV erstellt : {CSV_FILE}")
print(f"JSON erstellt: {JSON_FILE}")
print(f"Transaktionen: {transaction_count}")
print(f"Wochensumme : {week_sum:.2f} EUR")
print(f"Ausgaben    : {week_expenses:.2f} EUR")