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

import hashlib
import json
from pathlib import Path
import time

# === ZDE JEN PŘIDÁVEJ ADRESÁŘE ===
DIRECTORIES = [
    Path(r"U:\Dropbox\Ordinace\Dokumentace_zpracovaná"),
    Path(r"U:\Dropbox\Ordinace\LAB-PDF"),
]

CHUNK = 65536


def md5_file(path: Path) -> str:
    h = hashlib.md5()
    with path.open("rb") as f:
        for chunk in iter(lambda: f.read(CHUNK), b""):
            h.update(chunk)
    return h.hexdigest()


def load_db(db_path: Path) -> dict:
    if db_path.exists():
        with db_path.open("r", encoding="utf-8") as f:
            return json.load(f)
    return {}


def save_db(db: dict, db_path: Path):
    with db_path.open("w", encoding="utf-8") as f:
        json.dump(db, f, ensure_ascii=False, indent=2)


def process_directory(root: Path):
    print("\n===========================================")
    print(f"📁 ZPRACOVÁVÁM ADRESÁŘ: {root}")
    print("===========================================\n")

    db_path = root / "processed_files.json"

    # Načíst databázi
    db = load_db(db_path)
    print(f"Načteno z DB: {len(db)} záznamů")

    # Projít souborový systém
    files_in_fs = {}
    start_scan = time.time()

    for f in root.rglob("*"):
        if f.is_file() and f.suffix.lower() != ".json":
            stat = f.stat()
            files_in_fs[f.name] = {
                "size": stat.st_size,
                "mtime": int(stat.st_mtime),
                "path": str(f)
            }

    print(f"Nalezeno v FS: {len(files_in_fs)} souborů")
    print(f"Čas skenu: {time.time() - start_scan:.2f} s\n")

    new_files = 0
    changed_files = 0

    for fname, info in files_in_fs.items():

        size = info["size"]
        mtime = info["mtime"]

        # nový soubor?
        if fname not in db:
            print(f"Nový soubor → MD5: {fname}")
            new_files += 1
            db[fname] = {
                "size": size,
                "mtime": mtime,
                "md5": md5_file(Path(info["path"]))
            }
            continue

        # změněný soubor?
        if db[fname]["size"] != size or db[fname]["mtime"] != mtime:
            print(f"Změněný soubor → MD5: {fname}")
            changed_files += 1
            db[fname] = {
                "size": size,
                "mtime": mtime,
                "md5": md5_file(Path(info["path"]))
            }

    # uložit databázi
    save_db(db, db_path)

    print("\n=== Výsledky ===")
    print(f" Nové soubory:     {new_files}")
    print(f" Změněné soubory:  {changed_files}")
    print(f" Celkem v DB:      {len(db)}")
    print(f" Databáze:         {db_path}")
    print("=============================\n")


def main():
    for directory in DIRECTORIES:
        process_directory(directory)


if __name__ == "__main__":
    main()