import { lstat, readlink } from "node:fs/promises";
import { fileURLToPath } from "node:url";
import { describe, it, expect } from "vitest";
import { createFixture } from "../test-utils/index.ts";
import { copySkills, findProjectRoot } from "./sync.ts";

describe("copySkills", () => {
  it("symlinks each skill into the destination", async () => {
    const fixture = await createFixture({
      "source-skills": {
        build: {
          "SKILL.md": "---\nname: build\ndescription: Build the project.\n---\nbody",
        },
      },
    });

    const source = new URL("source-skills/", fixture.root);
    const dest = new URL("project/skills/", fixture.root);

    const skills = await copySkills({ source, dest });

    expect(skills).toEqual([{ name: "build", description: "Build the project." }]);

    // The destination entry must be a symlink, not a copy.
    const linkPath = fileURLToPath(new URL("build", dest));
    expect((await lstat(linkPath)).isSymbolicLink()).toBe(true);

    // And it must resolve back to the source skill.
    expect(await readlink(linkPath)).toBe("../../source-skills/build");

    // Reading through the link reaches the real file.
    expect(await fixture.text("project/skills/build/SKILL.md")).toContain("name: build");
  });

  it("is idempotent and never touches the source on re-sync", async () => {
    const fixture = await createFixture({
      "source-skills": {
        build: {
          "SKILL.md": "---\nname: build\ndescription: Build the project.\n---\nbody",
        },
      },
    });

    const source = new URL("source-skills/", fixture.root);
    const dest = new URL("project/skills/", fixture.root);

    const first = await copySkills({ source, dest });
    // Re-running must not throw and must yield the same result.
    const second = await copySkills({ source, dest });

    expect(second).toEqual(first);
    // The source skill files must survive a re-sync.
    expect(await fixture.text("source-skills/build/SKILL.md")).toContain("name: build");
    expect(await fixture.text("project/skills/build/SKILL.md")).toContain("name: build");
  });
});

describe("findProjectRoot", () => {
  it("finds the nearest package.json walking up from the start directory", async () => {
    const fixture = await createFixture({
      "package.json": { name: "my-app", version: "1.0.0" },
      src: { nested: { "index.ts": "export const x = 1" } },
    });

    const result = await findProjectRoot(fileURLToPath(new URL("src/nested", fixture.root)));

    expect(result).toEqual({ kind: "found", root: fixture.root });
  });

  it("reports self when the nearest package is @bomb.sh/tools", async () => {
    const fixture = await createFixture({
      "package.json": { name: "@bomb.sh/tools", version: "1.0.0" },
    });

    const result = await findProjectRoot(fileURLToPath(fixture.root));

    expect(result).toEqual({ kind: "self" });
  });

  it("reports not-found when no package.json exists in any parent", async () => {
    const fixture = await createFixture({
      src: { "index.ts": "export const x = 1" },
    });

    // A nested directory in a fixture that has no package.json anywhere up to /tmp.
    const result = await findProjectRoot(fileURLToPath(new URL("src", fixture.root)));

    expect(result).toEqual({ kind: "not-found" });
  });
});