lots more refactoring

inire/seeds.py

@@ -0,0 +1,48 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import Literal
+
+
+BendDirection = Literal["CW", "CCW"]
+
+
+@dataclass(frozen=True, slots=True)
+class StraightSeed:
+    length: float
+
+    def __post_init__(self) -> None:
+        object.__setattr__(self, "length", float(self.length))
+
+
+@dataclass(frozen=True, slots=True)
+class Bend90Seed:
+    radius: float
+    direction: BendDirection
+
+    def __post_init__(self) -> None:
+        object.__setattr__(self, "radius", float(self.radius))
+
+
+@dataclass(frozen=True, slots=True)
+class SBendSeed:
+    offset: float
+    radius: float
+
+    def __post_init__(self) -> None:
+        object.__setattr__(self, "offset", float(self.offset))
+        object.__setattr__(self, "radius", float(self.radius))
+
+
+PathSegmentSeed = StraightSeed | Bend90Seed | SBendSeed
+
+
+@dataclass(frozen=True, slots=True)
+class PathSeed:
+    segments: tuple[PathSegmentSeed, ...]
+
+    def __post_init__(self) -> None:
+        segments = tuple(self.segments)
+        if any(not isinstance(segment, StraightSeed | Bend90Seed | SBendSeed) for segment in segments):
+            raise TypeError("PathSeed segments must be StraightSeed, Bend90Seed, or SBendSeed instances")
+        object.__setattr__(self, "segments", segments)