'use strict';

const test = require('node:test');
const assert = require('node:assert/strict');
const fs = require('node:fs');
const os = require('node:os');
const path = require('node:path');
const { run } = require('../src/cli');

class Sink {
  constructor() { this.chunks = []; }
  write(s) { this.chunks.push(s); }
  get text() { return this.chunks.join(''); }
}

const FIX_ATLAS = path.join(__dirname, 'fixtures', 'atlases');
const FIX_DSL = path.join(__dirname, 'fixtures', 'dsl');

function tmpOut(name) {
  return path.join(os.tmpdir(), `${name}.json`);
}

test('build: minimal DSL → valid v2 JSON file', () => {
  const out = new Sink(); const err = new Sink();
  const outPath = tmpOut('minimal');
  try {
    const code = run(['build', path.join(FIX_DSL, 'minimal.txt'), outPath, '--atlas-dir', FIX_ATLAS], { out, err });
    assert.equal(code, 0, err.text);
    const json = JSON.parse(fs.readFileSync(outPath, 'utf8'));
    assert.equal(json.schema_version, 2);
    assert.equal(json.id, 'minimal');           // derived from out filename
    assert.deepEqual(json.size, { w: 4, h: 4 });
    assert.deepEqual(json.atlases, ['atlas_a']);
    assert.equal(json.layers.surface.tiles.length, 16);
  } finally {
    if (fs.existsSync(outPath)) fs.unlinkSync(outPath);
  }
});

test('build: full DSL with id directive overrides filename-derived id', () => {
  const out = new Sink(); const err = new Sink();
  const outPath = tmpOut('full');
  try {
    const code = run(['build', path.join(FIX_DSL, 'full.txt'), outPath, '--atlas-dir', FIX_ATLAS], { out, err });
    assert.equal(code, 0, err.text);
    const json = JSON.parse(fs.readFileSync(outPath, 'utf8'));
    assert.equal(json.id, 'full_demo');
    assert.deepEqual(Object.keys(json.layers).sort(), ['surface', 'wall']);
    assert.equal(json.roof.length, 16);
  } finally {
    if (fs.existsSync(outPath)) fs.unlinkSync(outPath);
  }
});

test('build: out-of-bounds DSL reports file:line on stderr, exit 1', () => {
  const out = new Sink(); const err = new Sink();
  const outPath = tmpOut('err');
  const inPath = path.join(FIX_DSL, 'error_oob.txt');
  const code = run(['build', inPath, outPath, '--atlas-dir', FIX_ATLAS], { out, err });
  assert.equal(code, 1);
  assert.match(err.text, /error_oob\.txt:4:/);
  assert.match(err.text, /out of bounds/);
  // Output file must NOT exist
  assert.equal(fs.existsSync(outPath), false);
});

test('build: missing --atlas-dir for DSL that needs atlases → error', () => {
  const out = new Sink(); const err = new Sink();
  const outPath = tmpOut('noatlas');
  const code = run(['build', path.join(FIX_DSL, 'minimal.txt'), outPath, '--atlas-dir', '/no/such/dir'], { out, err });
  assert.equal(code, 1);
  assert.match(err.text, /error/i);
  if (fs.existsSync(outPath)) fs.unlinkSync(outPath);
});

test('build: insufficient positional args prints usage, exit 1', () => {
  const out = new Sink(); const err = new Sink();
  const code = run(['build', 'only_one_arg.txt'], { out, err });
  assert.equal(code, 1);
  assert.match(err.text, /usage: sporel-mapper build/);
});

test('build: duplicate atlas across --atlas-dir paths warns on stderr but exits 0', () => {
  // Use both fixture dirs (atlases + atlases-dup)
  const FIX_DUP = path.join(__dirname, 'fixtures', 'atlases-dup');
  const out = new Sink(); const err = new Sink();
  const outPath = tmpOut('dup');
  try {
    const code = run(
      ['build', path.join(FIX_DSL, 'minimal.txt'), outPath, '--atlas-dir', FIX_ATLAS, '--atlas-dir', FIX_DUP],
      { out, err }
    );
    assert.equal(code, 0, err.text);
    assert.match(err.text, /warning.*atlas_a.*duplicate/i);
  } finally {
    if (fs.existsSync(outPath)) fs.unlinkSync(outPath);
  }
});