"""
Packet model for LoRa route simulation.

Defines packet types and structure for HELLO, DATA, and ACK packets.
"""

from dataclasses import dataclass
from enum import IntEnum
from typing import Optional


class PacketType(IntEnum):
    """Packet type enumeration."""

    HELLO = 1
    DATA = 2
    ACK = 3


@dataclass
class Packet:
    """
    LoRa packet structure.

    Attributes:
        type: Packet type (HELLO, DATA, or ACK)
        src: Source node ID
        dst: Destination node ID (-1 for broadcast)
        seq: Sequence number
        hop: Current hop count
        payload: Optional payload data
        rssi: Received signal strength indicator (set on receive)
    """

    type: PacketType
    src: int
    dst: int
    seq: int
    hop: int = 0
    payload: Optional[str] = None
    rssi: Optional[float] = None  # Set by receiver

    def __repr__(self) -> str:
        return (
            f"Packet({self.type.name}, src={self.src}, dst={self.dst}, "
            f"seq={self.seq}, hop={self.hop})"
        )

    @property
    def is_broadcast(self) -> bool:
        """Check if packet is broadcast (dst = -1)."""
        return self.dst == -1

    @property
    def is_hello(self) -> bool:
        """Check if packet is a HELLO packet."""
        return self.type == PacketType.HELLO

    @property
    def is_data(self) -> bool:
        """Check if packet is a DATA packet."""
        return self.type == PacketType.DATA

    @property
    def is_ack(self) -> bool:
        """Check if packet is an ACK packet."""
        return self.type == PacketType.ACK

    def to_dict(self) -> dict:
        """Convert packet to dictionary for serialization."""
        return {
            "type": self.type.name,
            "src": self.src,
            "dst": self.dst,
            "seq": self.seq,
            "hop": self.hop,
            "payload": self.payload,
            "rssi": self.rssi,
        }