Implement buy flow and migrate DTOs to schemas

Move DTO definitions from dto/ to schemas/ and update imports.
Add buy handler with FSM state management for device selection,
whitelist toggling, and duration choice. Include pricing logic,
inline keyboards, and new configuration fields.

handlers/buy.py

@@ -1,10 +1,153 @@
-from aiogram import Router
+from typing import Optional
+from aiogram import Router, F
 from aiogram.types import CallbackQuery
 from aiogram.fsm.context import FSMContext
 
-from dto.di import DependenciesDTO
-
+from keyboards.client import devices_selector, duration_selector
+from misc.utils import calculate_price, convert_int_to_duration
+from schemas.subscriptions import SubscriptionPlan
+from states.buy import SubscriptionStorage
+from texts import (
+    CALLBACK_FALLBACK,
+    CONTEXT_REINITIATED,
+    NOTHING_PLACEHOLDER,
+    SUBSCRIPTION_DEVICE_SELECTOR,
+    SUBSCRIPTION_DURATION_SELECTOR,
+)
+from config import settings
 
 router = Router()
 
-# @router.callback_query()
+
+@router.callback_query(F.data == "buy")
+async def buy_init(cb: CallbackQuery, state: FSMContext):
+    await state.clear()
+
+    ctx = SubscriptionPlan()
+    await cb.message.edit_text(
+        SUBSCRIPTION_DEVICE_SELECTOR.format(price=calculate_price(ctx)),
+        reply_markup=devices_selector(settings.min_devices),
+    )
+
+    await state.set_state(SubscriptionStorage.devices)
+    await state.set_data({"ctx": ctx})
+
+
+@router.callback_query(F.data.startswith("devices:"))
+async def device_count_select(cb: CallbackQuery, state: FSMContext):
+    data = await state.get_data()
+    await state.clear()
+
+    ctx: Optional[SubscriptionPlan] = data.get("ctx", SubscriptionPlan())
+
+    cb_data = cb.data.split(":")
+    devices = int(cb_data[1]) if cb_data[1].isdigit() else settings.min_devices
+    ctx.devices = devices
+    ctx.whitelists = ctx.whitelists or devices >= settings.whitelist_device_threshold
+
+    await cb.message.edit_text(
+        SUBSCRIPTION_DEVICE_SELECTOR.format(price=calculate_price(ctx)),
+        reply_markup=devices_selector(current=ctx.devices, whitelists=ctx.whitelists),
+    )
+    await state.set_state(SubscriptionStorage.devices)
+    await state.set_data({"ctx": ctx})
+
+
+@router.callback_query(SubscriptionStorage.devices, F.data == "whitelist:toggle")
+async def toggle_whitelists(cb: CallbackQuery, state: FSMContext):
+    data = await state.get_data()
+    await state.clear()
+
+    ctx: Optional[SubscriptionPlan] = data.get("ctx")
+    if not ctx:
+        await state.set_state(SubscriptionPlan())
+        await state.set_data({"ctx": ctx})
+        await cb.answer(CALLBACK_FALLBACK)
+        return
+    ctx.whitelists = (
+        not ctx.whitelists or ctx.devices >= settings.whitelist_device_threshold
+    )
+
+    try:
+        await cb.message.edit_reply_markup(
+            SUBSCRIPTION_DEVICE_SELECTOR.format(price=calculate_price(ctx)),
+            reply_markup=devices_selector(
+                current=ctx.devices, whitelists=ctx.whitelists
+            ),
+        )
+    except Exception as exc:
+        if "message is not modified:" in str(exc):
+            await cb.answer(NOTHING_PLACEHOLDER)
+        else:
+            await cb.answer(CALLBACK_FALLBACK)
+    await state.set_state(SubscriptionStorage.devices)
+    await state.set_data({"ctx": ctx})
+
+
+@router.callback_query(SubscriptionStorage.devices, F.data == "confirm")
+async def select_duration_init(cb: CallbackQuery, state: FSMContext):
+    data = await state.get_data()
+    await state.clear()
+
+    ctx: Optional[SubscriptionPlan] = data.get("ctx")
+    if not ctx:
+        await state.set_state(SubscriptionPlan())
+        await state.set_data({"ctx": ctx})
+        await cb.answer(CALLBACK_FALLBACK)
+        return
+
+    try:
+        await cb.message.edit_text(
+            SUBSCRIPTION_DURATION_SELECTOR.format(price=calculate_price(ctx)),
+            reply_markup=duration_selector(
+                current=ctx.duration, back_cb=f"devices:{ctx.devices}"
+            ),
+        )
+    except Exception as exc:
+        if "message is not modified:" in str(exc):
+            await cb.answer(NOTHING_PLACEHOLDER)
+        else:
+            await cb.answer(CALLBACK_FALLBACK)
+            raise
+
+    await state.set_state(SubscriptionStorage.duration)
+    await state.set_data({"ctx": ctx})
+
+
+@router.callback_query(F.data.startswith("duration:"))
+async def select_duration(cb: CallbackQuery, state: FSMContext):
+    data = await state.get_data()
+    await state.clear()
+
+    ctx: Optional[SubscriptionPlan] = data.get("ctx")
+    if not ctx:
+        await state.set_state()
+        await state.set_data({"ctx": ctx})
+        await cb.answer(CONTEXT_REINITIATED)
+        ctx = SubscriptionPlan()
+
+    cb_data = cb.data.split(":")
+    duration = int(cb_data[1]) if cb_data[1].isdigit() else 1
+    ctx.duration = convert_int_to_duration(duration)
+    try:
+        await cb.message.edit_text(
+            SUBSCRIPTION_DURATION_SELECTOR.format(price=calculate_price(ctx)),
+            reply_markup=duration_selector(
+                current=ctx.duration, back_cb=f"devices:{ctx.devices}"
+            ),
+        )
+    except Exception as exc:
+        if "message is not modified:" in str(exc):
+            await cb.answer(NOTHING_PLACEHOLDER)
+        else:
+            await cb.answer(CALLBACK_FALLBACK)
+            raise
+
+    await state.set_state(SubscriptionStorage.duration)
+    await state.set_data({"ctx": ctx})
+
+
+@router.callback_query(SubscriptionStorage.duration, F.data == "confirm")
+async def proceed_to_checkout(cb: CallbackQuery, state: FSMContext):
+    await cb.answer("yay!!!! fuck off.")
+    ...