import useBodyScrollLock from "./use-body-scroll-lock";

import { cleanup, renderHook } from "@testing-library/react";

describe("useBodyScrollLock", () => {
  beforeEach(() => {
    cleanup();
    document.body.style.overflow = "";
    document.body.style.marginRight = "";
  });

  afterEach(() => {
    cleanup();
    document.body.style.overflow = "";
    document.body.style.marginRight = "";
  });

  describe("Scroll locking (isOpen=true)", () => {
    it("sets body overflow to hidden when isOpen is true", () => {
      renderHook(() => useBodyScrollLock(true, false));
      expect(document.body.style.overflow).toBe("hidden");
    });

    it("sets marginRight based on scrollbar width when isOpen is true", () => {
      renderHook(() => useBodyScrollLock(true, false));
      const scrollbarWidth =
        window.innerWidth - document.documentElement.clientWidth;
      expect(document.body.style.marginRight).toBe(`${scrollbarWidth}px`);
    });
  });

  describe("Scroll unlocking (isOpen=false)", () => {
    it("resets overflow to unset when isOpen=false and hideScrollOnIsOpenFalse=true", () => {
      renderHook(() => useBodyScrollLock(false, true));
      expect(document.body.style.overflow).toBe("unset");
    });

    it("preserves existing overflow when isOpen=false and hideScrollOnIsOpenFalse=false", () => {
      document.body.style.overflow = "auto";
      renderHook(() => useBodyScrollLock(false, false));
      expect(document.body.style.overflow).toBe("auto");
    });

    it("attempts to set marginRight to unset when isOpen is false", () => {
      const calls: string[] = [];
      const original = Object.getOwnPropertyDescriptor(
        CSSStyleDeclaration.prototype,
        "marginRight"
      );
      Object.defineProperty(document.body.style, "marginRight", {
        set(val: string) {
          calls.push(val);
        },
        get() {
          return "";
        },
        configurable: true,
      });
      renderHook(() => useBodyScrollLock(false, false));
      expect(calls).toContain("unset");
      // Restore
      if (original) {
        Object.defineProperty(
          CSSStyleDeclaration.prototype,
          "marginRight",
          original
        );
      }
    });

    it("attempts to set marginRight to unset for isOpen false regardless of hideScroll", () => {
      const calls: string[] = [];
      Object.defineProperty(document.body.style, "marginRight", {
        set(val: string) {
          calls.push(val);
        },
        get() {
          return "";
        },
        configurable: true,
      });
      renderHook(() => useBodyScrollLock(false, true));
      expect(calls).toContain("unset");
    });
  });

  describe("Cleanup on unmount", () => {
    it("resets body overflow to unset on unmount", () => {
      const { unmount } = renderHook(() => useBodyScrollLock(true, false));
      expect(document.body.style.overflow).toBe("hidden");
      unmount();
      expect(document.body.style.overflow).toBe("unset");
    });

    it("resets overflow on unmount even when isOpen was false", () => {
      const { unmount } = renderHook(() => useBodyScrollLock(false, true));
      unmount();
      expect(document.body.style.overflow).toBe("unset");
    });
  });

  describe("Dependency changes", () => {
    it("locks scroll when isOpen changes from false to true", () => {
      const { rerender } = renderHook(
        ({ isOpen, hide }) => useBodyScrollLock(isOpen, hide),
        { initialProps: { isOpen: false, hide: false } }
      );
      expect(document.body.style.overflow).not.toBe("hidden");
      rerender({ isOpen: true, hide: false });
      expect(document.body.style.overflow).toBe("hidden");
    });

    it("unlocks scroll when isOpen changes from true to false with hideScroll=true", () => {
      const { rerender } = renderHook(
        ({ isOpen, hide }) => useBodyScrollLock(isOpen, hide),
        { initialProps: { isOpen: true, hide: true } }
      );
      expect(document.body.style.overflow).toBe("hidden");
      rerender({ isOpen: false, hide: true });
      expect(document.body.style.overflow).toBe("unset");
    });

    it("runs cleanup then effect when dependencies change", () => {
      const { rerender } = renderHook(
        ({ isOpen, hide }) => useBodyScrollLock(isOpen, hide),
        { initialProps: { isOpen: true, hide: false } }
      );
      expect(document.body.style.overflow).toBe("hidden");
      // Change hideScrollOnIsOpenFalse - triggers cleanup + re-run
      rerender({ isOpen: true, hide: true });
      expect(document.body.style.overflow).toBe("hidden");
    });
  });
});