1 files changed, 26 insertions, 0 deletions
diff --git a/src/types.ts b/src/types.ts
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+/**
+ * Type definitions for the tire size data used throughout the app.
+ * Each size entry has a human-readable label and a diameter in millimeters.
+ */
+
+/** A single rim or tire size option from our reference data. */
+export interface SizeOption {
+  label: string;
+  diameter_mm: number;
+}
+
+/** The shape of the imported tire_sizes.json file. */
+export interface TireSizeData {
+  wheel_sizes: SizeOption[];
+  tire_sizes: SizeOption[];
+}
+
+/**
+ * Results from the circumference calculation.
+ * All values derived from: circumference = 3.13772 * (2 * tire + rim)
+ */
+export interface CircumferenceResult {
+  mm: number;
+  cm: number;
+  inches: number;
+}