app.py

import asyncio
from aiogram import Bot, Dispatcher, F
from aiogram.client.default import DefaultBotProperties
from aiogram.enums import ParseMode
from aiogram.types import Message, CallbackQuery, FSInputFile, BufferedInputFile
from aiogram.filters import CommandStart
from pathlib import Path

from settings import BOT_TOKEN, DATA_DIR, PRODUCT_A_DIR, PRODUCT_B_DIR, PRODUCT_C_DIR, log
from db import DB
from inventory import Inventory
from keyboards import main_menu, product_actions

from bank import build_qr_for_user
from aiogram.filters import Command


bot = Bot(BOT_TOKEN, default=DefaultBotProperties(parse_mode=ParseMode.HTML))
dp = Dispatcher()

db = DB(DATA_DIR / 'shop.sqlite')

inv = Inventory({
    'A': Path(PRODUCT_A_DIR),
    'B': Path(PRODUCT_B_DIR),
    'C': Path(PRODUCT_C_DIR),
})

@dp.message(CommandStart())
async def start(m: Message):
    db.upsert_user(m.from_user.id, m.from_user.username or '', m.from_user.first_name or '')
    text = (f"CHÀO MỪNG {m.from_user.first_name or 'bạn'}\n"
            f"ID: <code>{m.from_user.id}</code>\n\n"
            f"Kho: A={inv.count_items('A')} | B={inv.count_items('B')} | C={inv.count_items('C')}\n"
            f"Chọn mặt hàng:")
    await m.answer(text, reply_markup=main_menu())

@dp.message(Command('nap'))
async def nap(m: Message):
    parts = (m.text or '').split()
    if len(parts) < 2:
        await m.reply("Dùng: /nap <sotien>")
        return
    try:
        amount = int(parts[1])
        if amount <= 0:
            raise ValueError
    except Exception:
        await m.reply("Số tiền không hợp lệ.")
        return

    path, caption = build_qr_for_user(m.from_user.id, amount)
    # Caption may include HTML (e.g., bold VND)
    await m.reply_photo(photo=FSInputFile(path), caption=caption, parse_mode='HTML')

@dp.callback_query(F.data.startswith('back:'))
async def back_main(cq: CallbackQuery):
    await cq.message.edit_text(
        f"Kho: A={inv.count_items('A')} | B={inv.count_items('B')} | C={inv.count_items('C')}\nChọn mặt hàng:",
        reply_markup=main_menu()
    )
    await cq.answer()

@dp.callback_query(F.data.startswith('prod:'))
async def product_menu(cq: CallbackQuery):
    product = cq.data.split(':')[1]
    stock = inv.count_items(product)
    await cq.message.edit_text(f"Mặt hàng {product} — tồn: {stock}\nChọn số lượng:", reply_markup=product_actions(product))
    await cq.answer()

@dp.callback_query(F.data.startswith('qty:'))
async def ask_qty(cq: CallbackQuery):
    product = cq.data.split(':')[1]
    await cq.message.edit_text(f"Nhập số lượng muốn mua cho mặt hàng {product} (trả lời tin nhắn này bằng số)." )
    # save state by pinning product to message via caption entities? use simple approach: store in message
    cq.message.conf = {'await_qty_for': product}
    await cq.answer()

# Fallback: parse user reply to quantity after prompt
@dp.message()
async def any_msg(m: Message):
    # crude state check: if user replied to bot message containing 'Nhập số lượng'
    if m.reply_to_message and 'Nhập số lượng muốn mua' in (m.reply_to_message.text or ''):
        product = next((ch for ch in ['A','B','C'] if f'mặt hàng {ch}' in (m.reply_to_message.text or '')), 'A')
        try:
            qty = int(m.text.strip())
            if qty <= 0:
                raise ValueError
        except Exception:
            await m.reply('Số lượng không hợp lệ. Vui lòng nhập số nguyên > 0.')
            return
        await process_purchase(m, product, qty)
    else:
        await m.reply("Dùng /start để mở menu.")

@dp.callback_query(F.data.startswith('buy:'))
async def quick_buy(cq: CallbackQuery):
    _, product, qty = cq.data.split(':')
    qty = int(qty)
    # Respond immediately to remove Telegram's loading state
    try:
        await cq.answer('Đang xử lý...')
    except Exception:
        pass
    await process_purchase(cq.message, product, qty, from_callback=cq)

async def process_purchase(target_msg_or_cq_message, product: str, qty: int, from_callback: CallbackQuery|None=None):
    chat_id = target_msg_or_cq_message.chat.id
    user = target_msg_or_cq_message.from_user
    try:
        _filename, data = await inv.allocate(product, qty)
    except ValueError as e:
        if from_callback:
            await from_callback.answer(str(e), show_alert=True)
        else:
            await bot.send_message(chat_id, str(e))
        return

    send_name = f"{product}-{qty}-{user.id}.txt"
    # Send from memory buffer for speed (avoid disk I/O)
    await bot.send_document(
        chat_id,
        document=BufferedInputFile(data, filename=send_name),
        caption=f"Đã giao {qty} mục hàng {product}"
    )

    # Log to DB in background to reduce latency
    try:
        await asyncio.to_thread(db.add_order, user.id, product, qty, send_name)
    except Exception:
        # fallback synchronous
        db.add_order(user.id, product, qty, send_name)
    log.info(f"Order user={user.id} product={product} qty={qty}")

if __name__ == '__main__':
    asyncio.run(dp.start_polling(bot))