from uuid import UUID

import asyncpg

from app.exceptions import NotFoundError, OutOfStockError
from app.models.orders import OrderCreate


async def create_order(db: asyncpg.Connection, user_id: str, data: OrderCreate) -> dict:
    async with db.transaction():
        total = 0.0
        line_items = []

        for item in data.items:
            product = await db.fetchrow(
                "SELECT id, name, price, stock_quantity FROM products WHERE id = $1 AND is_hidden = false",
                str(item.product_id),
            )
            if not product:
                raise NotFoundError("product")
            if product["stock_quantity"] < item.quantity:
                raise OutOfStockError(product["name"])

            line_items.append({
                "product_id": str(item.product_id),
                "product_name": product["name"],
                "quantity": item.quantity,
                "unit_price": float(product["price"]),
            })
            total += float(product["price"]) * item.quantity

            await db.execute(
                "UPDATE products SET stock_quantity = stock_quantity - $2 WHERE id = $1",
                str(item.product_id), item.quantity,
            )

        total = round(total, 2)
        order = await db.fetchrow(
            """
            INSERT INTO orders (user_id, status, total_amount, shipping_address, notes)
            VALUES ($1, 'pending', $2, $3, $4)
            RETURNING *
            """,
            user_id, total,
            data.shipping_address, data.notes,
        )
        order_id = str(order["id"])

        for li in line_items:
            await db.execute(
                """
                INSERT INTO order_items (order_id, product_id, quantity, unit_price)
                VALUES ($1, $2, $3, $4)
                """,
                order_id, li["product_id"], li["quantity"], li["unit_price"],
            )

    return {"order_id": order_id, "amount": total}


async def get_order(db: asyncpg.Connection, order_id: UUID, user_id: str | None = None) -> dict:
    query = "SELECT o.* FROM orders o WHERE o.id = $1"
    params: list = [str(order_id)]

    if user_id:
        query += " AND o.user_id = $2"
        params.append(user_id)

    row = await db.fetchrow(query, *params)
    if not row:
        raise NotFoundError("order")

    items = await db.fetch(
        """
        SELECT oi.id, oi.product_id, p.name as product_name, oi.quantity, oi.unit_price
        FROM order_items oi
        JOIN products p ON p.id = oi.product_id
        WHERE oi.order_id = $1
        """,
        str(order_id),
    )

    result = dict(row)
    result["items"] = [dict(i) for i in items]
    return result


async def list_orders(
    db: asyncpg.Connection,
    page: int,
    per_page: int,
    offset: int,
    user_id: str | None = None,
    status: str | None = None,
) -> tuple[list[dict], int]:
    conditions: list[str] = []
    params: list = []

    if user_id:
        params.append(user_id)
        conditions.append(f"o.user_id = ${len(params)}")
    if status:
        params.append(status)
        conditions.append(f"o.status = ${len(params)}")

    where = f"WHERE {' AND '.join(conditions)}" if conditions else ""
    total = await db.fetchval(f"SELECT COUNT(*) FROM orders o {where}", *params)

    params.extend([per_page, offset])
    rows = await db.fetch(
        f"""
        SELECT o.id, o.user_id, o.status, o.total_amount,
               o.shipping_address, o.notes, o.created_at, o.updated_at,
               p.full_name AS client_name, p.email AS client_email, p.phone AS client_phone
        FROM orders o
        LEFT JOIN profiles p ON p.id = o.user_id
        {where}
        ORDER BY o.created_at DESC
        LIMIT ${len(params) - 1} OFFSET ${len(params)}
        """,
        *params,
    )
    return [dict(r) for r in rows], total


async def update_order_status(db: asyncpg.Connection, order_id: UUID, status: str, actor_id: str) -> dict:
    row = await db.fetchrow(
        "UPDATE orders SET status = $2, updated_at = now() WHERE id = $1 RETURNING *",
        str(order_id), status,
    )
    if not row:
        raise NotFoundError("order")
    await _log(db, actor_id, "order.status_updated", "order", str(order_id), {"status": status})
    return dict(row)


async def refund_order(db: asyncpg.Connection, order_id: UUID, actor_id: str, amount: float | None, reason: str | None) -> dict:
    order = await db.fetchrow("SELECT * FROM orders WHERE id = $1", str(order_id))
    if not order:
        raise NotFoundError("order")
    if not order["stripe_payment_intent_id"]:
        from app.exceptions import AppError
        raise AppError("NO_PAYMENT", "No payment found for this order", 400)

    refund = await stripe_service.create_refund(
        order["stripe_payment_intent_id"],
        amount=amount,
        reason=reason,
    )

    new_status = "refunded"
    row = await db.fetchrow(
        "UPDATE orders SET status = $2, stripe_refund_id = $3, updated_at = now() WHERE id = $1 RETURNING *",
        str(order_id), new_status, refund.id,
    )
    await _log(db, actor_id, "order.refunded", "order", str(order_id), {"refund_id": refund.id})
    return dict(row)


async def handle_payment_succeeded(db: asyncpg.Connection, payment_intent_id: str, entity_id: str):
    row = await db.fetchrow(
        "UPDATE orders SET status = 'paid', updated_at = now() WHERE id = $1 AND stripe_payment_intent_id = $2 RETURNING *",
        entity_id, payment_intent_id,
    )
    if row:
        user = await db.fetchrow("SELECT email FROM profiles WHERE id = $1", str(row["user_id"]))
        if user:
            from app.services.email_service import send_order_confirmed
            await send_order_confirmed(user["email"], entity_id, float(row["total_amount"]))


async def handle_payment_failed(db: asyncpg.Connection, payment_intent_id: str, entity_id: str):
    order = await db.fetchrow("SELECT * FROM orders WHERE id = $1", entity_id)
    if not order or order["status"] != "pending":
        return

    await db.execute(
        "UPDATE orders SET status = 'cancelled', updated_at = now() WHERE id = $1",
        entity_id,
    )
    # Restore stock
    items = await db.fetch("SELECT product_id, quantity FROM order_items WHERE order_id = $1", entity_id)
    for item in items:
        await db.execute(
            "UPDATE products SET stock_quantity = stock_quantity + $2 WHERE id = $1",
            str(item["product_id"]), item["quantity"],
        )


async def _log(db, actor_id, action, entity_type, entity_id, metadata=None):
    await db.execute(
        "INSERT INTO activity_log (actor_id, action, entity_type, entity_id, metadata) VALUES ($1, $2, $3, $4, $5)",
        actor_id, action, entity_type, entity_id, metadata,
    )