update point tier rule

src/utils/pointRule.ts

@@ -0,0 +1,29 @@
+import type { PointRuleTierForm } from "@/types/Point";
+
+export function resolveNonNegativeInteger(value: string): number | undefined {
+	if (!value.trim()) {
+		return undefined;
+	}
+	const numberValue = Number(value);
+	return Number.isSafeInteger(numberValue) && !(numberValue < 0) ? numberValue : undefined;
+}
+
+export function getTierMinValue(tierList: PointRuleTierForm[], index: number): number | undefined {
+	if (index === 0) {
+		return 0;
+	}
+	const previousMax = resolveNonNegativeInteger(tierList[index - 1]?.maxText || "");
+	if (previousMax === undefined || !Number.isSafeInteger(previousMax + 1)) {
+		return undefined;
+	}
+	return previousMax + 1;
+}
+
+export function getTierMinText(tierList: PointRuleTierForm[], index: number): string {
+	const min = getTierMinValue(tierList, index);
+	return min === undefined ? "待填写" : String(min);
+}
+
+export function isLastTier(tierList: PointRuleTierForm[], index: number): boolean {
+	return index === tierList.length - 1;
+}