[#498] useFunnel 작성 (#501)

* feat: assert 유틸 함수 작성

* feat: useFunnel 커스텀 훅 작성

* feat: Funnel 컴포넌트 작성

* refactor: useFunnel 개선

src/hooks/useFunnel.tsx

@@ -0,0 +1,88 @@
+'use client';
+
+import { useEffect, useMemo, useRef } from 'react';
+
+import type { FunnelProps, StepProps } from '@/v1/base/Funnel/Funnel';
+import { assert } from '@/utils/assert';
+
+import { Funnel, Step } from '@/v1/base/Funnel/Funnel';
+import { usePathname, useRouter, useSearchParams } from 'next/navigation';
+
+export type NonEmptyArray<T> = readonly [T, ...T[]];
+
+type RouteFunnelProps<Steps extends NonEmptyArray<string>> = Omit<
+  FunnelProps<Steps>,
+  'steps' | 'step'
+>;
+
+type FunnelComponent<Steps extends NonEmptyArray<string>> = ((
+  props: RouteFunnelProps<Steps>
+) => JSX.Element) & {
+  Step: (props: StepProps<Steps>) => JSX.Element;
+};
+
+const DEFAULT_STEP_QUERY_KEY = 'funnel-step';
+
+/**
+ * 사용자에게 초기 step을 강제하고 싶을 땐
+ * option의 initialStep을 작성해 주세요.
+ */
+export const useFunnel = <Steps extends NonEmptyArray<string>>(
+  steps: Steps,
+  options?: {
+    stepQueryKey?: string;
+    initialStep?: Steps[number];
+    onStepChange?: (name: Steps[number]) => void;
+  }
+): readonly [FunnelComponent<Steps>, (step: Steps[number]) => void] => {
+  const router = useRouter();
+  const searchParams = useSearchParams();
+  const pathname = usePathname();
+
+  const hasRunOnce = useRef(false);
+
+  const step = searchParams.get('funnel-step') as string;
+  const stepQueryKey = options?.stepQueryKey ?? DEFAULT_STEP_QUERY_KEY;
+
+  useEffect(() => {
+    if (options?.initialStep && !hasRunOnce.current) {
+      hasRunOnce.current = true;
+      router.replace(pathname);
+    }
+  }, [options?.initialStep, router, pathname]);
+
+  assert(steps.length > 0, 'steps가 비어있습니다.');
+
+  const FunnelComponent = useMemo(
+    () =>
+      Object.assign(
+        function RouteFunnel(props: RouteFunnelProps<Steps>) {
+          const currentStep = step ?? options?.initialStep;
+
+          assert(
+            currentStep != null,
+            `표시할 스텝을 ${stepQueryKey} 쿼리 파라미터에 지정해주세요. 쿼리 파라미터가 없을 때 초기 스텝을 렌더하려면 useFunnel의 두 번째 파라미터 options에 initialStep을 지정해주세요.`
+          );
+
+          return <Funnel<Steps> steps={steps} step={currentStep} {...props} />;
+        },
+        {
+          Step,
+        }
+      ),
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+    [step]
+  );
+
+  const setStep = (step: Steps[number]) => {
+    const params = new URLSearchParams(searchParams.toString());
+    params.set('funnel-step', `${step}`);
+
+    return router.replace(`?${params.toString()}`);
+  };
+
+  return [FunnelComponent, setStep] as unknown as readonly [
+    FunnelComponent<Steps>,
+    (step: Steps[number]) => Promise<void>
+  ];
+};

src/utils/assert.ts

@@ -0,0 +1,9 @@
+export const assert = (condition: unknown, error: Error | string) => {
+  if (!condition) {
+    if (typeof error === 'string') {
+      throw new Error(error);
+    } else {
+      throw error;
+    }
+  }
+};

src/v1/base/Funnel/Funnel.tsx

@@ -0,0 +1,42 @@
+import { Children, ReactElement, ReactNode, isValidElement } from 'react';
+
+import type { NonEmptyArray } from '@/hooks/useFunnel';
+
+import { assert } from '@/utils/assert';
+
+export interface FunnelProps<Steps extends NonEmptyArray<string>> {
+  steps: Steps;
+  step: Steps[number];
+  children:
+    | Array<ReactElement<StepProps<Steps>>>
+    | ReactElement<StepProps<Steps>>;
+}
+
+export const Funnel = <Steps extends NonEmptyArray<string>>({
+  steps,
+  step,
+  children,
+}: FunnelProps<Steps>) => {
+  const validChildren = Children.toArray(children)
+    .filter(isValidElement)
+    .filter(i =>
+      steps.includes((i.props as Partial<StepProps<Steps>>).name ?? '')
+    ) as Array<ReactElement<StepProps<Steps>>>;
+
+  const targetStep = validChildren.find(child => child.props.name === step);
+
+  assert(targetStep != null, `${step} 스텝 컴포넌트를 찾지 못했습니다.`);
+
+  return <>{targetStep}</>;
+};
+
+export interface StepProps<Steps extends NonEmptyArray<string>> {
+  name: Steps[number];
+  children: ReactNode;
+}
+
+export const Step = <T extends NonEmptyArray<string>>({
+  children,
+}: StepProps<T>) => {
+  return <>{children}</>;
+};