import { strict as assert } from 'node:assert';
import { readFile, rm, writeFile } from 'node:fs/promises';
import path from 'node:path';
import { afterEach, beforeEach, describe, it } from 'node:test';
import { SectionError, SectionStore, slugify } from '../src/storage/sections.ts';
import { tempDir } from './support/harness.ts';

const SEED = [
  { slug: 'food', label: 'Food', shortLabel: 'Food', note: null, order: 1 },
  { slug: 'bar', label: 'Bar', shortLabel: 'Bar', note: null, order: 2 },
];

let dataDir: string;

beforeEach(async () => {
  dataDir = await tempDir('sections');
});

afterEach(async () => {
  await rm(dataDir, { recursive: true, force: true });
});

async function loaded(seed = SEED) {
  const store = new SectionStore({ dataDir, seed });
  await store.load();
  return store;
}

describe('slugify', () => {
  it('turns the labels people type into stable web addresses', () => {
    assert.equal(slugify('Straight Drinks'), 'straight-drinks');
    assert.equal(slugify("What's On"), 'whats-on');
    assert.equal(slugify('Desserts & Coffee'), 'desserts-coffee');
    assert.equal(slugify('  Bar  '), 'bar');
    assert.equal(slugify('Wine / Beer'), 'wine-beer');
    assert.equal(slugify('----'), '');
  });
});

describe('SectionStore', () => {
  it('seeds from the config the first time and writes the file', async () => {
    const store = await loaded();
    assert.deepEqual(
      store.list().map((section) => section.slug),
      ['food', 'bar'],
    );

    const file = JSON.parse(await readFile(path.join(dataDir, 'sections.json'), 'utf8'));
    assert.equal(file.sections.length, 2);
  });

  it('keeps the file as the source of truth afterwards, ignoring the seed', async () => {
    await loaded();
    const second = new SectionStore({ dataDir, seed: [] });
    await second.load();
    assert.deepEqual(
      second.list().map((section) => section.slug),
      ['food', 'bar'],
    );
  });

  it('refuses to serve an unreadable file rather than silently reseeding', async () => {
    await writeFile(path.join(dataDir, 'sections.json'), '{ not json');
    const store = new SectionStore({ dataDir, seed: SEED });
    await assert.rejects(() => store.load(), SectionError);
  });

  it('complains if it is read before loading', () => {
    const store = new SectionStore({ dataDir, seed: SEED });
    assert.throws(() => store.list(), /load\(\)/);
  });

  it('adds a category at the end, with a slug from the name', async () => {
    const store = await loaded();
    const created = await store.create({ label: 'Straight Drinks' });
    assert.equal(created.slug, 'straight-drinks');
    assert.equal(created.order, 3);
    assert.deepEqual(
      store.list().map((section) => section.label),
      ['Food', 'Bar', 'Straight Drinks'],
    );
  });

  it('makes a slug unique, and steers around the names the app reserves', async () => {
    const store = await loaded();
    await store.create({ label: 'Desserts' });
    assert.equal((await store.create({ label: 'Desserts' })).slug, 'desserts-2');
    assert.equal((await store.create({ label: 'Admin' })).slug, 'admin-2');
    assert.equal((await store.create({ label: 'Media' })).slug, 'media-2');
  });

  it('rejects an empty name and a name that makes no web address', async () => {
    const store = await loaded();
    await assert.rejects(() => store.create({ label: '   ' }), SectionError);
    await assert.rejects(() => store.create({ label: '!!!' }), SectionError);
  });

  it('renames without moving the web address customers already have', async () => {
    const store = await loaded();
    const renamed = await store.rename('bar', { label: 'Bar & Cocktails' });
    assert.equal(renamed.label, 'Bar & Cocktails');
    assert.equal(renamed.slug, 'bar');
    assert.equal(store.bySlug('bar')?.label, 'Bar & Cocktails');
  });

  it('moves a category and renumbers the rest', async () => {
    const store = await loaded();
    await store.move('bar', 'up');
    assert.deepEqual(
      store.list().map((section) => section.slug),
      ['bar', 'food'],
    );
    assert.deepEqual(
      store.list().map((section) => section.order),
      [1, 2],
    );

    // Past either end is a no-op, not an error.
    await store.move('bar', 'up');
    assert.deepEqual(
      store.list().map((section) => section.slug),
      ['bar', 'food'],
    );
  });

  it('removes a category and closes the gap in the order', async () => {
    const store = await loaded();
    await store.create({ label: 'Wine' });
    await store.remove('bar');
    assert.deepEqual(
      store.list().map((section) => [section.slug, section.order]),
      [
        ['food', 1],
        ['wine', 2],
      ],
    );
  });

  it('reports an unknown slug rather than inventing one', async () => {
    const store = await loaded();
    await assert.rejects(() => store.rename('pizza', { label: 'Pizza' }), SectionError);
    await assert.rejects(() => store.remove('pizza'), SectionError);
  });

  it('survives add, rename, move and remove being read by a second instance', async () => {
    const store = await loaded();
    const created = await store.create({ label: 'Desserts' });
    await store.rename(created.slug, { label: 'Puddings' });
    await store.move(created.slug, 'up');

    const reopened = new SectionStore({ dataDir, seed: [] });
    await reopened.load();
    assert.deepEqual(
      reopened.list().map((section) => section.label),
      ['Food', 'Puddings', 'Bar'],
    );
  });
});