import assert from "node:assert/strict"
import { mkdtempSync, mkdirSync, readFileSync, rmSync, writeFileSync } from "node:fs"
import { tmpdir } from "node:os"
import path from "node:path"
import { test } from "node:test"
import { diffSnapshots, hashDir, listSkillDirs, recordNewSkills } from "../scripts/sync-upstream.ts"

function fixture() {
  const dir = mkdtempSync(path.join(tmpdir(), "sync-test-"))
  const skill = (root: string, bucket: string, name: string, body: string, extra?: string) => {
    mkdirSync(path.join(root, bucket, name), { recursive: true })
    writeFileSync(path.join(root, bucket, name, "SKILL.md"), body)
    if (extra) writeFileSync(path.join(root, bucket, name, "EXTRA.md"), extra)
  }
  return { dir, skill }
}

test("listSkillDirs finds only dirs containing SKILL.md", () => {
  const { dir, skill } = fixture()
  try {
    skill(dir, "engineering", "tdd", "---\nname: tdd\n---\n")
    skill(dir, "misc", "wizard", "---\nname: wizard\n---\n")
    mkdirSync(path.join(dir, "deprecated"), { recursive: true })
    writeFileSync(path.join(dir, "deprecated", "README.md"), "empty bucket")
    mkdirSync(path.join(dir, "engineering", "not-a-skill"), { recursive: true })
    assert.deepEqual(listSkillDirs(dir), ["engineering/tdd", "misc/wizard"])
    assert.deepEqual(listSkillDirs(path.join(dir, "missing")), [])
  } finally {
    rmSync(dir, { recursive: true, force: true })
  }
})

test("diffSnapshots reports added, removed and changed skill dirs", () => {
  const { dir, skill } = fixture()
  const before = path.join(dir, "before")
  const after = path.join(dir, "after")
  try {
    skill(before, "engineering", "tdd", "v1")
    skill(before, "engineering", "gone", "v1")
    skill(after, "engineering", "tdd", "v2")
    skill(after, "productivity", "fresh", "v1")
    assert.deepEqual(diffSnapshots(before, after), {
      added: ["productivity/fresh"],
      removed: ["engineering/gone"],
      changed: ["engineering/tdd"],
    })
  } finally {
    rmSync(dir, { recursive: true, force: true })
  }
})

test("hashDir ignores file mtime and is order-independent", () => {
  const { dir, skill } = fixture()
  const a = path.join(dir, "a")
  const b = path.join(dir, "b")
  try {
    skill(a, "x", "s", "same", "extra")
    skill(b, "x", "s", "same", "extra")
    assert.equal(hashDir(path.join(a, "x", "s")), hashDir(path.join(b, "x", "s")))
    writeFileSync(path.join(b, "x", "s", "EXTRA.md"), "different")
    assert.notEqual(hashDir(path.join(a, "x", "s")), hashDir(path.join(b, "x", "s")))
  } finally {
    rmSync(dir, { recursive: true, force: true })
  }
})

test("recordNewSkills appends needs-review entries once and leaves known skills alone", () => {
  const { dir } = fixture()
  const file = path.join(dir, "classification.json")
  try {
    writeFileSync(
      file,
      JSON.stringify({ skills: [{ name: "tdd", bucket: "engineering", status: "analyzed" }] }),
    )
    const fresh = recordNewSkills(file, ["engineering/tdd", "misc/newcomer"])
    assert.deepEqual(fresh, ["newcomer"])
    const doc = JSON.parse(readFileSync(file, "utf8"))
    assert.equal(doc.skills.length, 2)
    assert.equal(doc.skills[1].status, "needs-review")
    assert.equal(doc.skills[1].classification, "skill")
    // idempotent: second run adds nothing
    assert.deepEqual(recordNewSkills(file, ["misc/newcomer"]), [])
  } finally {
    rmSync(dir, { recursive: true, force: true })
  }
})