mirror of
https://github.com/dcs-liberation/dcs_liberation.git
synced 2025-11-10 14:22:26 +00:00
08abe36443
The dataclass contructor will not automatically convert the int in the JSON file to the enum type, so our enum equivalence check was not actually working, and could result in us re-allocating a TACAN channel that was used by the map. Fixing this problem surfaces a latent bug, where we can't actually treat duplicate map TACAN channels as a bug because some channels are used by multiple airports in PG.
114 lines
3.4 KiB
Python
114 lines
3.4 KiB
Python
"""TACAN channel handling."""
|
|
from __future__ import annotations
|
|
|
|
import re
|
|
from dataclasses import dataclass
|
|
from enum import Enum
|
|
from typing import Dict, Iterator, Set
|
|
|
|
|
|
class TacanUsage(Enum):
|
|
TransmitReceive = "transmit receive"
|
|
AirToAir = "air to air"
|
|
|
|
|
|
class TacanBand(Enum):
|
|
X = "X"
|
|
Y = "Y"
|
|
|
|
def range(self) -> Iterator["TacanChannel"]:
|
|
"""Returns an iterator over the channels in this band."""
|
|
return (TacanChannel(x, self) for x in range(1, 126 + 1))
|
|
|
|
def valid_channels(self, usage: TacanUsage) -> Iterator["TacanChannel"]:
|
|
for x in self.range():
|
|
if x.number not in UNAVAILABLE[usage][self]:
|
|
yield x
|
|
|
|
|
|
# Avoid certain TACAN channels for various reasons
|
|
# https://forums.eagle.ru/topic/276390-datalink-issue/
|
|
UNAVAILABLE = {
|
|
TacanUsage.TransmitReceive: {
|
|
TacanBand.X: set(range(2, 30 + 1)) | set(range(47, 63 + 1)),
|
|
TacanBand.Y: set(range(2, 30 + 1)) | set(range(64, 92 + 1)),
|
|
},
|
|
TacanUsage.AirToAir: {
|
|
TacanBand.X: set(range(1, 36 + 1)) | set(range(64, 99 + 1)),
|
|
TacanBand.Y: set(range(1, 36 + 1)) | set(range(64, 99 + 1)),
|
|
},
|
|
}
|
|
|
|
|
|
@dataclass(frozen=True)
|
|
class TacanChannel:
|
|
number: int
|
|
band: TacanBand
|
|
|
|
def __str__(self) -> str:
|
|
return f"{self.number}{self.band.value}"
|
|
|
|
@classmethod
|
|
def parse(cls, text: str) -> TacanChannel:
|
|
match = re.match(r"""^(\d{1,3})([XY])$""", text)
|
|
if match is None:
|
|
raise ValueError(f"Could not parse TACAN from {text}")
|
|
number = int(match.group(1))
|
|
if not number:
|
|
raise ValueError("TACAN channel cannot be 0")
|
|
return TacanChannel(number, TacanBand(match.group(2)))
|
|
|
|
|
|
class OutOfTacanChannelsError(RuntimeError):
|
|
"""Raised when all channels in this band have been allocated."""
|
|
|
|
def __init__(self, band: TacanBand) -> None:
|
|
super().__init__(f"No available channels in TACAN {band.value} band")
|
|
|
|
|
|
class TacanRegistry:
|
|
"""Manages allocation of TACAN channels."""
|
|
|
|
def __init__(self) -> None:
|
|
self.allocated_channels: Set[TacanChannel] = set()
|
|
self.allocators: Dict[TacanBand, Dict[TacanUsage, Iterator[TacanChannel]]] = {}
|
|
|
|
for band in TacanBand:
|
|
self.allocators[band] = {}
|
|
for usage in TacanUsage:
|
|
self.allocators[band][usage] = band.valid_channels(usage)
|
|
|
|
def alloc_for_band(
|
|
self, band: TacanBand, intended_usage: TacanUsage
|
|
) -> TacanChannel:
|
|
"""Allocates a TACAN channel in the given band.
|
|
|
|
Args:
|
|
band: The TACAN band to allocate a channel for.
|
|
intended_usage: What the caller intends to use the tacan channel for.
|
|
|
|
Returns:
|
|
A TACAN channel in the given band.
|
|
|
|
Raises:
|
|
OutOfTacanChannelsError: All channels compatible with the given radio are
|
|
already allocated.
|
|
"""
|
|
allocator = self.allocators[band][intended_usage]
|
|
try:
|
|
while (channel := next(allocator)) in self.allocated_channels:
|
|
pass
|
|
return channel
|
|
except StopIteration:
|
|
raise OutOfTacanChannelsError(band)
|
|
|
|
def mark_unavailable(self, channel: TacanChannel) -> None:
|
|
"""Reserves the given channel.
|
|
|
|
Reserving a channel ensures that it will not be allocated in the future.
|
|
|
|
Args:
|
|
channel: The channel to reserve.
|
|
"""
|
|
self.allocated_channels.add(channel)
|