import json
import os
from typing import List
from models import Event

DATA_FILE = "calendar_data.json"

def load_events() -> List[Event]:
    """Загружает события из JSON файла"""
    if not os.path.exists(DATA_FILE):
        return []
    
    try:
        with open(DATA_FILE, 'r', encoding='utf-8') as f:
            data = json.load(f)
            return [Event.from_dict(item) for item in data]
    except (json.JSONDecodeError, FileNotFoundError):
        return []

def save_events(events: List[Event]) -> None:
    """Сохраняет события в JSON файл"""
    with open(DATA_FILE, 'w', encoding='utf-8') as f:
        data = [event.to_dict() for event in events]
        json.dump(data, f, ensure_ascii=False, indent=2)

def add_event(event: Event) -> None:
    """Добавляет новое событие"""
    events = load_events()
    events.append(event)
    save_events(events)

def remove_event(index: int) -> bool:
    """Удаляет событие по индексу (начиная с 0)"""
    events = load_events()
    if 0 <= index < len(events):
        del events[index]
        save_events(events)
        return True
    return False

def get_events_by_date(date: str) -> List[Event]:
    """Возвращает события на конкретную дату"""
    events = load_events()
    return [e for e in events if e.date == date]