import assert from "node:assert/strict";
import { mkdtemp, mkdir, writeFile, rm, lstat, symlink } from "node:fs/promises";
import { tmpdir } from "node:os";
import path from "node:path";
import test from "node:test";

import { removeTarget } from "../lib/skill-manager-core.mjs";

// ── Happy path: remove existing directory ─────────────────────────────────

test("removeTarget removes an installed skill directory", async () => {
  const dir = await mkdtemp(path.join(tmpdir(), "smc-remove-dir-"));
  try {
    const skillsRoot = path.join(dir, "skills");
    const target = path.join(skillsRoot, "create-plan");
    await mkdir(target, { recursive: true });
    await writeFile(path.join(target, "SKILL.md"), "---\nname: create-plan\n---\n");

    const op = { kind: "skill", action: "remove", target, skillsRoot };
    const result = await removeTarget(op);

    assert.equal(result.status, "ok");
    let exists = true;
    try {
      await lstat(target);
    } catch {
      exists = false;
    }
    assert.equal(exists, false, "target directory should be gone");
  } finally {
    await rm(dir, { recursive: true, force: true });
  }
});

// ── Happy path: remove symbolic link ─────────────────────────────────────

test("removeTarget removes a symlink without following it", async () => {
  const dir = await mkdtemp(path.join(tmpdir(), "smc-remove-sym-"));
  try {
    const skillsRoot = path.join(dir, "skills");
    const realDir = path.join(dir, "real-skill");
    const target = path.join(skillsRoot, "create-plan");

    await mkdir(skillsRoot, { recursive: true });
    await mkdir(realDir, { recursive: true });
    await writeFile(path.join(realDir, "SKILL.md"), "---\nname: create-plan\n---\n");
    await symlink(realDir, target, "dir");

    const op = { kind: "skill", action: "remove", target, skillsRoot };
    const result = await removeTarget(op);

    assert.equal(result.status, "ok");

    // symlink itself should be gone
    let symlinkExists = true;
    try {
      await lstat(target);
    } catch {
      symlinkExists = false;
    }
    assert.equal(symlinkExists, false, "symlink should be removed");

    // real directory should still exist
    const realStat = await lstat(realDir);
    assert.ok(realStat.isDirectory(), "real directory must not be touched");
  } finally {
    await rm(dir, { recursive: true, force: true });
  }
});

// ── Missing skill (partial state): target does not exist ─────────────────

test("removeTarget succeeds when target does not exist (idempotent)", async () => {
  const dir = await mkdtemp(path.join(tmpdir(), "smc-remove-missing-"));
  try {
    const skillsRoot = path.join(dir, "skills");
    const target = path.join(skillsRoot, "create-plan");
    await mkdir(skillsRoot, { recursive: true });
    // target intentionally NOT created

    const op = { kind: "skill", action: "remove", target, skillsRoot };
    const result = await removeTarget(op);

    assert.equal(result.status, "ok");
  } finally {
    await rm(dir, { recursive: true, force: true });
  }
});

// ── Partial state: directory exists but is empty ─────────────────────────

test("removeTarget removes an empty skill directory", async () => {
  const dir = await mkdtemp(path.join(tmpdir(), "smc-remove-empty-"));
  try {
    const skillsRoot = path.join(dir, "skills");
    const target = path.join(skillsRoot, "create-plan");
    await mkdir(target, { recursive: true });
    // directory exists but has no SKILL.md (partial install state)

    const op = { kind: "skill", action: "remove", target, skillsRoot };
    const result = await removeTarget(op);

    assert.equal(result.status, "ok");
    let exists = true;
    try {
      await lstat(target);
    } catch {
      exists = false;
    }
    assert.equal(exists, false);
  } finally {
    await rm(dir, { recursive: true, force: true });
  }
});

// ── Safety: refuses to remove path outside skills root ────────────────────

test("removeTarget refuses to remove a path outside the skills root", async () => {
  const dir = await mkdtemp(path.join(tmpdir(), "smc-remove-outside-"));
  try {
    const skillsRoot = path.join(dir, "skills");
    const outsideTarget = path.join(dir, "outside");
    await mkdir(skillsRoot, { recursive: true });
    await mkdir(outsideTarget, { recursive: true });

    const op = {
      kind: "skill",
      action: "remove",
      target: outsideTarget,
      skillsRoot,
    };

    await assert.rejects(() => removeTarget(op), /outside skills root/);
  } finally {
    await rm(dir, { recursive: true, force: true });
  }
});