import { describe, expect, it, vi } from "vitest";
import { dispatch } from "../src/vue-helper";

/**
 * 创建模拟的 Vue ComponentPublicInstance
 */
function createMockInstance(
  componentName?: string,
  parent?: any,
  root?: any,
) {
  const instance = {
    $parent: parent ?? null,
    $root: root ?? null,
    $options: { componentName: componentName ?? null },
    $emit: vi.fn(),
  };
  return instance;
}

describe("dispatch", () => {
  it("应在祖先组件中找到匹配的 componentName 并触发事件", () => {
    const targetComponentName = "FormComponent";
    const grandParent = createMockInstance(targetComponentName);
    const parent = createMockInstance(undefined, grandParent, grandParent);
    const thisArg = createMockInstance(undefined, parent, grandParent);

    // thisArg.$parent → parent, parent.$parent → grandParent
    parent.$parent = grandParent;

    dispatch(thisArg, targetComponentName as any, "validate", { field: "name" });

    expect(grandParent.$emit).toHaveBeenCalledWith("validate", { field: "name" });
  });

  it("应从直接父组件开始查找", () => {
    const targetComponentName = "DirectParent";
    const parent = createMockInstance(targetComponentName);
    const thisArg = createMockInstance(undefined, parent, parent);

    dispatch(thisArg, targetComponentName as any, "change", null);

    expect(parent.$emit).toHaveBeenCalledWith("change", null);
  });

  it("当没有父组件且有根组件时，应从根组件开始查找", () => {
    const targetComponentName = "RootComponent";
    const root = createMockInstance(targetComponentName);
    const thisArg = createMockInstance(undefined, null, root);

    dispatch(thisArg, targetComponentName as any, "init", undefined);

    expect(root.$emit).toHaveBeenCalledWith("init", undefined);
  });

  it("当 thisArg.$parent 和 thisArg.$root 都为 null 时，应直接返回", () => {
    const thisArg = createMockInstance(undefined, null, null);
    const targetComponentName = "FormComponent" as any;

    // 不应抛出错误
    expect(() => dispatch(thisArg, targetComponentName, "validate", {})).not.toThrow();
  });

  it("当找不到匹配的祖先组件时，不应触发任何事件", () => {
    const grandParent = createMockInstance("OtherComponent");
    const parent = createMockInstance("AnotherComponent", grandParent, grandParent);
    const thisArg = createMockInstance(undefined, parent, grandParent);

    dispatch(thisArg, "NonExistentComponent" as any, "validate", {});

    expect(grandParent.$emit).not.toHaveBeenCalled();
    expect(parent.$emit).not.toHaveBeenCalled();
  });

  it("应在多级父组件链中找到匹配的祖先", () => {
    const targetComponentName = "GrandGrandParent";
    const grandGrandParent = createMockInstance(targetComponentName);
    const grandParent = createMockInstance("GrandParent", grandGrandParent, grandGrandParent);
    const parent = createMockInstance("Parent", grandParent, grandGrandParent);
    const thisArg = createMockInstance(undefined, parent, grandGrandParent);

    dispatch(thisArg, targetComponentName as any, "submit", { data: "test" });

    expect(grandGrandParent.$emit).toHaveBeenCalledWith("submit", { data: "test" });
    expect(grandParent.$emit).not.toHaveBeenCalled();
    expect(parent.$emit).not.toHaveBeenCalled();
  });

  it("找到的第一个匹配组件后，不应继续向上查找", () => {
    const targetComponentName = "Parent";
    const grandParent = createMockInstance(targetComponentName); // 更上层也有同名组件
    const parent = createMockInstance(targetComponentName, grandParent, grandParent);
    const thisArg = createMockInstance(undefined, parent, grandParent);

    dispatch(thisArg, targetComponentName as any, "click", true);

    // 应该触发 parent 的事件，而非 grandParent 的
    expect(parent.$emit).toHaveBeenCalledWith("click", true);
    expect(grandParent.$emit).not.toHaveBeenCalled();
  });

  it("应支持传递各种类型的参数", () => {
    const parent = createMockInstance("Target");
    const thisArg = createMockInstance(undefined, parent, parent);

    // 字符串
    dispatch(thisArg, "Target" as any, "event1", "hello");
    expect(parent.$emit).toHaveBeenCalledWith("event1", "hello");

    // 数字
    dispatch(thisArg, "Target" as any, "event2", 42);
    expect(parent.$emit).toHaveBeenCalledWith("event2", 42);

    // 数组
    dispatch(thisArg, "Target" as any, "event3", [1, 2, 3]);
    expect(parent.$emit).toHaveBeenCalledWith("event3", [1, 2, 3]);

    // undefined
    dispatch(thisArg, "Target" as any, "event4", undefined);
    expect(parent.$emit).toHaveBeenCalledWith("event4", undefined);
  });

  it("当祖先组件的 componentName 为 undefined 时，应跳过继续查找", () => {
    const targetComponentName = "TargetComponent";
    const grandParent = createMockInstance(targetComponentName);
    // parent 没有 componentName
    const parent = createMockInstance(undefined, grandParent, grandParent);
    const thisArg = createMockInstance(undefined, parent, grandParent);

    dispatch(thisArg, targetComponentName as any, "save", {});

    expect(grandParent.$emit).toHaveBeenCalledWith("save", {});
  });
});