#!/usr/bin/env python3
# -*- coding: utf-8 -*-

"""
FIO MULTI–ACCOUNT IMPORTER — FULLY COMMENTED VERSION
====================================================

This script downloads transactions for **multiple Fio bank accounts**
(using their API tokens) and imports them into a MySQL database
(`fio.transactions` table).

It also saves the raw JSON responses into a folder structure
for backup / debugging / later use.

Main features:
    • Reads all accounts from accounts.json
    • Downloads last N days (default 90)
    • Saves JSON files to disk
    • Extracts all transactions with safe parsing
    • Inserts into MySQL with ON DUPLICATE KEY UPDATE
    • Efficient batch insertion (executemany)
"""

import os
import json
import time
from datetime import date, timedelta
from pathlib import Path

import requests      # used to call Fio REST API
import pymysql       # MySQL driver


# =========================================
# CONFIGURATION
# =========================================

# JSON file containing multiple account configs:
# [
#   { "name": "CZK rodina", "account_number": "2100046291", "token": "xxx" },
#   ...
# ]
ACCOUNTS_FILE = r"c:\users\vlado\PycharmProjects\FIO\accounts.json"

# Directory where raw JSON files from Fio API will be stored.
JSON_BASE_DIR = r"z:\Dropbox\!!!Days\Downloads Z230\Fio"

# MySQL connection parameters
DB = {
    "host": "192.168.1.76",
    "port": 3307,
    "user": "root",
    "password": "Vlado9674+",
    "database": "fio",
    "charset": "utf8mb4",
}

# How many transactions insert per batch (performance tuning)
BATCH_SIZE = 500

# How many days back we load from Fio (default = last 90 days)
DAYS_BACK = 90


# =========================================
# HELPERS
# =========================================

def load_accounts(path: str):
    """
    Reads accounts.json and does simple validation to ensure
    each entry contains: name, account_number, token.
    """
    with open(path, "r", encoding="utf-8") as f:
        accounts = json.load(f)

    for acc in accounts:
        for key in ("name", "account_number", "token"):
            if key not in acc:
                raise ValueError(f"Missing '{key}' in account config: {acc}")

    return accounts


def fio_url_for_period(token: str, d_from: date, d_to: date) -> str:
    """
    Constructs the exact URL for Fio REST API "periods" endpoint.
    Example:
        https://fioapi.fio.cz/v1/rest/periods/<token>/2025-01-01/2025-01-31/transactions.json
    """
    from_str = d_from.strftime("%Y-%m-%d")
    to_str = d_to.strftime("%Y-%m-%d")
    return f"https://fioapi.fio.cz/v1/rest/periods/{token}/{from_str}/{to_str}/transactions.json"


def fetch_fio_json(token: str, d_from: date, d_to: date):
    """
    Calls Fio API and fetches JSON.
    Handles HTTP errors and JSON decoding errors.
    """
    url = fio_url_for_period(token, d_from, d_to)
    resp = requests.get(url, timeout=30)

    if resp.status_code != 200:
        print(f"  ❌ HTTP {resp.status_code} from Fio: {url}")
        return None

    try:
        return resp.json()
    except json.JSONDecodeError:
        print("  ❌ Cannot decode JSON from Fio response")
        return None


def safe_col(t: dict, n: int):
    """
    SAFE ACCESSOR for Fio transaction column numbers.

    Fio JSON schema example:
        "column5": { "name": "VS", "value": "123456" }

    But the structure is NOT guaranteed to exist.
    So this function prevents KeyError or NoneType errors.

    Returns:
        t["columnN"]["value"] or None
    """
    key = f"column{n}"
    val = t.get(key)
    if not val:
        return None
    return val.get("value")


def clean_date(dt_str: str):
    """
    Fio returns dates like: "2025-02-14+0100"
    We strip timezone → "2025-02-14"
    """
    if not dt_str:
        return None
    return dt_str[:10]


def ensure_dir(path: Path):
    """Creates directory if it doesn’t exist."""
    path.mkdir(parents=True, exist_ok=True)


def save_json_for_account(base_dir: str, account_cfg: dict, data: dict, d_from: date, d_to: date):
    """
    Saves raw JSON to:
        <base_dir>/<account_number>/YYYY-MM-DD_to_YYYY-MM-DD.json

    Useful for debugging, backups, or re-imports.
    """
    acc_num_raw = account_cfg["account_number"]
    acc_folder_name = acc_num_raw.replace("/", "_")  # sanitize dir name for filesystem

    out_dir = Path(base_dir) / acc_folder_name
    ensure_dir(out_dir)

    filename = f"{d_from.strftime('%Y-%m-%d')}_to_{d_to.strftime('%Y-%m-%d')}.json"
    out_path = out_dir / filename

    with open(out_path, "w", encoding="utf-8") as f:
        json.dump(data, f, ensure_ascii=False, indent=2)

    return out_path


# =========================================
# MAIN IMPORT LOGIC
# =========================================

def main():
    start_all = time.time()

    # Calculate time range (last N days)
    today = date.today()
    d_from = today - timedelta(days=DAYS_BACK)
    d_to = today

    print("=== Fio multi-account import ===")
    print(f"Období: {d_from} až {d_to}")
    print("Načítám účty z JSON konfigurace...")

    # Load all accounts from accounts.json
    accounts = load_accounts(ACCOUNTS_FILE)
    print(f"  Účtů v konfiguraci: {len(accounts)}\n")

    # Connect to database
    conn = pymysql.connect(**DB)
    cur = conn.cursor()

    # SQL INSERT with ON DUPLICATE KEY UPDATE
    # This means: if transaction already exists (same unique key), update it.
    sql = """
    INSERT INTO transactions
    (
        datum, objem, mena, cislo_uctu, protiucet, kod_banky,
        ks, vs, ss, zprava_pro_prijemce, poznamka,
        id_operace, id_pokynu, ks_1, nazev_banky, nazev_protiuctu,
        ss_1, typ, upresneni_objem, upresneni_mena, vs_1, zadal
    )
    VALUES
    (
        %(datum)s, %(objem)s, %(mena)s, %(cislo_uctu)s, %(protiucet)s, %(kod_banky)s,
        %(ks)s, %(vs)s, %(ss)s, %(zprava)s, %(poznamka)s,
        %(id_operace)s, %(id_pokynu)s, %(ks1)s, %(nazev_banky)s, %(nazev_protiuctu)s,
        %(ss1)s, %(typ)s, %(upr_objem)s, %(upr_mena)s, %(vs1)s, %(zadal)s
    )
    ON DUPLICATE KEY UPDATE
        datum = VALUES(datum),
        objem = VALUES(objem),
        mena = VALUES(mena),
        protiucet = VALUES(protiucet),
        kod_banky = VALUES(kod_banky),
        ks = VALUES(ks),
        vs = VALUES(vs),
        ss = VALUES(ss),
        zprava_pro_prijemce = VALUES(zprava_pro_prijemce),
        poznamka = VALUES(poznamka),
        ks_1 = VALUES(ks_1),
        nazev_banky = VALUES(nazev_banky),
        nazev_protiuctu = VALUES(nazev_protiuctu),
        ss_1 = VALUES(ss_1),
        typ = VALUES(typ),
        upresneni_objem = VALUES(upresneni_objem),
        upresneni_mena = VALUES(upresneni_mena),
        vs_1 = VALUES(vs_1),
        zadal = VALUES(zadal)
    """

    total_inserted = 0

    # ======================================================
    # PROCESS EACH ACCOUNT IN accounts.json
    # ======================================================
    for acc in accounts:
        name = acc["name"]
        cfg_acc_num = acc["account_number"]
        token = acc["token"]

        print(f"--- Účet: {name} ({cfg_acc_num}) ---")
        t0 = time.time()

        # --- 1) Download JSON from Fio API
        data = fetch_fio_json(token, d_from, d_to)
        if data is None:
            print("  Přeskakuji, žádná data / chyba API.\n")
            continue

        # --- 2) Save raw JSON file to disk
        json_path = save_json_for_account(JSON_BASE_DIR, acc, data, d_from, d_to)
        print(f"  JSON uložen do: {json_path}")

        # --- 3) Extract transactions from JSON tree
        tlist = data["accountStatement"]["transactionList"].get("transaction", [])

        # FIO can return single transaction as an object (not list)
        if isinstance(tlist, dict):
            tlist = [tlist]

        print(f"  Počet transakcí v období: {len(tlist)}")

        if not tlist:
            print("  Žádné transakce, jdu dál.\n")
            continue

        # FIO returns account ID under accountStatement.info.accountId
        fio_acc_id = data["accountStatement"]["info"]["accountId"]

        # Warn if account ID in JSON doesn't match config (informational only)
        if cfg_acc_num and cfg_acc_num.split("/")[0] not in fio_acc_id:
            print(f"  ⚠ Upozornění: accountId z Fio ({fio_acc_id}) "
                  f"se neshoduje s account_number v konfiguraci ({cfg_acc_num})")

        # --- 4) Build list of MySQL rows
        rows = []
        for t in tlist:
            row = {
                "datum": clean_date(safe_col(t, 0)),
                "objem": safe_col(t, 1),
                "mena": safe_col(t, 14),

                "cislo_uctu": fio_acc_id,
                "protiucet": safe_col(t, 2),
                "kod_banky": safe_col(t, 3),

                "ks": safe_col(t, 4),
                "vs": safe_col(t, 5),
                "ss": safe_col(t, 6),

                "zprava": safe_col(t, 16),
                "poznamka": safe_col(t, 25),

                "id_operace": safe_col(t, 22),
                "id_pokynu": safe_col(t, 24),

                "ks1": safe_col(t, 18),
                "nazev_banky": safe_col(t, 15),
                "nazev_protiuctu": safe_col(t, 10),

                "ss1": safe_col(t, 19),
                "typ": safe_col(t, 8),

                "upr_objem": safe_col(t, 20),
                "upr_mena": safe_col(t, 21),
                "vs1": safe_col(t, 17),

                "zadal": safe_col(t, 12),
            }
            rows.append(row)

        # --- 5) INSERT rows into MySQL in batches
        inserted = 0

        for i in range(0, len(rows), BATCH_SIZE):
            chunk = rows[i : i + BATCH_SIZE]
            cur.executemany(sql, chunk)      # fast multi-row insert/update
            conn.commit()
            inserted += len(chunk)

        elapsed = time.time() - t0
        total_inserted += inserted

        print(f"  ✓ Zapsáno (insert/update): {inserted} řádků do DB za {elapsed:.2f} s\n")

    # Close DB
    cur.close()
    conn.close()

    total_elapsed = time.time() - start_all

    print(f"=== Hotovo. Celkem zapsáno {total_inserted} transakcí. "
          f"Celkový čas: {total_elapsed:.2f} s ===")


# ======================================================
# ENTRY POINT
# ======================================================

if __name__ == "__main__":
    main()