import assert from "node:assert/strict";
import { chmod, copyFile, mkdir, mkdtemp, readFile, readdir, rm, stat, writeFile } from "node:fs/promises";
import { spawnSync } from "node:child_process";
import { tmpdir } from "node:os";
import { dirname, join, resolve } from "node:path";
import test from "node:test";
import { fileURLToPath } from "node:url";

import {
  CURRENT_TOOL_SEARCH_DEFAULTS,
  LEGACY_TOOL_SEARCH_DEFAULTS,
  migrateToolSearchSettings,
} from "../scripts/migrate-tool-search-settings.mjs";

const repositoryRoot = resolve(dirname(fileURLToPath(import.meta.url)), "..");

async function fixture(t: test.TestContext): Promise<{ root: string; settingsPath: string }> {
  const root = await mkdtemp(join(tmpdir(), "my-pi-tool-search-migration-"));
  t.after(() => rm(root, { recursive: true, force: true }));
  return { root, settingsPath: join(root, "settings.json") };
}

test("migrates only the complete legacy default snapshot with a private backup", async (t) => {
  const { root, settingsPath } = await fixture(t);
  const original = {
    theme: "dark",
    toolSearch: LEGACY_TOOL_SEARCH_DEFAULTS,
    unrelated: { keep: true },
  };
  await writeFile(settingsPath, `${JSON.stringify(original, null, 2)}\n`, "utf8");
  await chmod(settingsPath, 0o644);

  const result = await migrateToolSearchSettings(settingsPath, { now: new Date("2026-08-28T12:34:56.789Z") });
  assert.equal(result.status, "migrated");
  assert.equal(result.backupPath, `${settingsPath}.bak.2026-08-28T12-34-56-789Z`);
  assert.deepEqual(JSON.parse(await readFile(settingsPath, "utf8")), {
    ...original,
    toolSearch: CURRENT_TOOL_SEARCH_DEFAULTS,
  });
  assert.deepEqual(JSON.parse(await readFile(result.backupPath!, "utf8")), original);
  assert.equal((await stat(settingsPath)).mode & 0o777, 0o600);
  assert.equal((await stat(result.backupPath!)).mode & 0o777, 0o600);
  assert.deepEqual((await readdir(root)).sort(), [
    "settings.json",
    "settings.json.bak.2026-08-28T12-34-56-789Z",
  ]);
});

test("does not remove a pre-existing backup when the timestamp collides", async (t) => {
  const { settingsPath } = await fixture(t);
  const now = new Date("2026-08-28T12:34:56.789Z");
  const backupPath = `${settingsPath}.bak.2026-08-28T12-34-56-789Z`;
  const original = JSON.stringify({ toolSearch: LEGACY_TOOL_SEARCH_DEFAULTS });
  await writeFile(settingsPath, original, "utf8");
  await writeFile(backupPath, "existing backup\n", "utf8");
  await assert.rejects(migrateToolSearchSettings(settingsPath, { now }), { code: "EEXIST" });
  assert.equal(await readFile(backupPath, "utf8"), "existing backup\n");
  assert.equal(await readFile(settingsPath, "utf8"), original);
});

test("preserves custom Tool Search settings even when they retain the old capacities", async (t) => {
  const { root, settingsPath } = await fixture(t);
  const custom = {
    toolSearch: {
      ...LEGACY_TOOL_SEARCH_DEFAULTS,
      alwaysEnabled: [...LEGACY_TOOL_SEARCH_DEFAULTS.alwaysEnabled, "custom_tool"],
    },
  };
  const original = `${JSON.stringify(custom, null, 2)}\n`;
  await writeFile(settingsPath, original, "utf8");

  assert.deepEqual(await migrateToolSearchSettings(settingsPath), { status: "custom" });
  assert.equal(await readFile(settingsPath, "utf8"), original);
  assert.deepEqual(await readdir(root), ["settings.json"]);
});

test("recognizes current defaults and skips files without a Tool Search section", async (t) => {
  const current = await fixture(t);
  await writeFile(current.settingsPath, JSON.stringify({ toolSearch: CURRENT_TOOL_SEARCH_DEFAULTS }), "utf8");
  assert.deepEqual(await migrateToolSearchSettings(current.settingsPath), { status: "current" });

  const unversioned = await fixture(t);
  const { bundleDefaultsVersion: _version, ...runtimeDefaults } = CURRENT_TOOL_SEARCH_DEFAULTS;
  await writeFile(unversioned.settingsPath, JSON.stringify({ toolSearch: runtimeDefaults }), "utf8");
  assert.deepEqual(await migrateToolSearchSettings(unversioned.settingsPath), { status: "current" });

  const absent = await fixture(t);
  await writeFile(absent.settingsPath, JSON.stringify({ theme: "dark" }), "utf8");
  assert.deepEqual(await migrateToolSearchSettings(absent.settingsPath), { status: "missing-section" });
});

test("fails safely for invalid JSON and reports a missing settings file", async (t) => {
  const invalid = await fixture(t);
  await writeFile(invalid.settingsPath, "{ invalid\n", "utf8");
  await assert.rejects(migrateToolSearchSettings(invalid.settingsPath), /invalid JSON/);
  assert.equal(await readFile(invalid.settingsPath, "utf8"), "{ invalid\n");

  const missing = await fixture(t);
  assert.deepEqual(await migrateToolSearchSettings(missing.settingsPath), { status: "missing" });
});

test("aborts when settings change before the atomic replacement", async (t) => {
  const { root, settingsPath } = await fixture(t);
  await writeFile(settingsPath, JSON.stringify({ toolSearch: LEGACY_TOOL_SEARCH_DEFAULTS }), "utf8");
  const competing = `${JSON.stringify({ toolSearch: { ...LEGACY_TOOL_SEARCH_DEFAULTS, maxActiveGroups: 4 } })}\n`;
  await assert.rejects(
    migrateToolSearchSettings(settingsPath, {
      beforeCommit: () => writeFile(settingsPath, competing, "utf8"),
    }),
    /changed during migration/,
  );
  assert.equal(await readFile(settingsPath, "utf8"), competing);
  const files = await readdir(root);
  assert.equal(files.filter((name) => name.includes(".bak.")).length, 1);
  assert.equal(files.some((name) => name.endsWith(".tmp")), false);
});

async function updateFixture(t: test.TestContext, piExitStatus = 0) {
  const root = await mkdtemp(join(tmpdir(), "my-pi-tool-search-update-"));
  t.after(() => rm(root, { recursive: true, force: true }));
  const home = join(root, "home");
  const bin = join(root, "bin");
  const agentDir = join(home, ".pi", "agent");
  const settingsPath = join(agentDir, "settings.json");
  const log = join(root, "pi.log");
  const updatedBundle = join(root, "updated-bundle");
  await mkdir(bin, { recursive: true });
  await mkdir(agentDir, { recursive: true });
  await mkdir(join(updatedBundle, "config"), { recursive: true });
  await mkdir(join(updatedBundle, "scripts"), { recursive: true });
  await copyFile(join(repositoryRoot, "config", "p10k.zsh"), join(updatedBundle, "config", "p10k.zsh"));
  await copyFile(
    join(repositoryRoot, "config", "hippo-memory-version"),
    join(updatedBundle, "config", "hippo-memory-version"),
  );
  await copyFile(
    join(repositoryRoot, "scripts", "migrate-tool-search-settings.mjs"),
    join(updatedBundle, "scripts", "migrate-tool-search-settings.mjs"),
  );
  await writeFile(
    join(bin, "pi"),
    `#!/bin/sh\nprintf 'pi %s\\n' "$*" >> "$MOCK_PI_LOG"\nexit ${piExitStatus}\n`,
    "utf8",
  );
  await chmod(join(bin, "pi"), 0o755);
  await writeFile(settingsPath, JSON.stringify({ toolSearch: LEGACY_TOOL_SEARCH_DEFAULTS }), "utf8");
  return {
    settingsPath,
    log,
    env: {
      ...process.env,
      HOME: home,
      XDG_CONFIG_HOME: join(home, ".config"),
      PI_CODING_AGENT_DIR: agentDir,
      PI_PACKAGE_SOURCE: updatedBundle,
      MOCK_PI_LOG: log,
      PATH: `${bin}:${dirname(process.execPath)}:/usr/bin:/bin`,
      ZSH: "",
      ZSH_CUSTOM: "",
      ZDOTDIR: home,
    },
  };
}

test("update.sh migrates the exact legacy snapshot after a successful package update", async (t) => {
  const fixture = await updateFixture(t);
  const result = spawnSync("sh", [join(repositoryRoot, "update.sh")], {
    cwd: repositoryRoot,
    env: fixture.env,
    encoding: "utf8",
    timeout: 30_000,
  });
  assert.equal(result.status, 0, result.stderr || result.stdout);
  assert.match(await readFile(fixture.log, "utf8"), /pi update .*updated-bundle/);
  assert.match(result.stdout, /旧版默认配置已迁移/);
  assert.deepEqual(JSON.parse(await readFile(fixture.settingsPath, "utf8")).toolSearch, CURRENT_TOOL_SEARCH_DEFAULTS);
  assert.equal((await stat(fixture.settingsPath)).mode & 0o777, 0o600);
});

test("update.sh does not migrate settings when pi update fails", async (t) => {
  const fixture = await updateFixture(t, 1);
  const before = await readFile(fixture.settingsPath, "utf8");
  const result = spawnSync("sh", [join(repositoryRoot, "update.sh")], {
    cwd: repositoryRoot,
    env: fixture.env,
    encoding: "utf8",
    timeout: 30_000,
  });
  assert.equal(result.status, 1);
  assert.equal(await readFile(fixture.settingsPath, "utf8"), before);
  assert.doesNotMatch(result.stdout, /旧版默认配置已迁移/);
});

test("update.sh preserves settings when the updated bundle helper cannot be located", async (t) => {
  const fixture = await updateFixture(t);
  const before = await readFile(fixture.settingsPath, "utf8");
  const result = spawnSync("sh", [join(repositoryRoot, "update.sh")], {
    cwd: repositoryRoot,
    env: { ...fixture.env, PI_PACKAGE_SOURCE: "unsupported:my-pi" },
    encoding: "utf8",
    timeout: 30_000,
  });
  assert.equal(result.status, 1);
  assert.equal(await readFile(fixture.settingsPath, "utf8"), before);
  assert.match(result.stderr, /无法定位升级后组合包中的 Tool Search/);
});