/**
 * Module-split scenarios for the Statum client.
 *
 * Each scenario runs in a FRESH QuickJS context (run.sh invokes this script
 * once per scenario) and loads a specific subset of the module files in a
 * specific order, proving:
 *
 *   1  core-alone        - window.statum, seam, overrides, driver-less render
 *   2  core+document     - render driver installed, handler order pinned
 *   3  core+doc+markdown - full order, statum.markdown API, test hatch
 *   4  core+markdown     - cherry-pick without the walk (crash-free)
 *   5  document alone    - guarded IIFE: console.error, nothing attached
 *   6  double register   - warns, order unchanged
 *   7  unknown after     - warns, registration position kept
 *
 * Usage: qjs tests/split/scenarios.js <1|2|3|4|5|6|7>
 */
import * as std from 'std';
import { installShim } from './shim.js';

// Repo root, as a CWD-relative path. run.sh (like tests/markdown/run.sh)
// always `cd`s to the repo root before invoking qjs, and QuickJS'
// std.loadFile resolves relative paths against the process CWD — the
// established in-repo idiom (see tests/markdown/spec-test.js).
var ROOT = '.';
var scenario = scriptArgs.length > 1 ? scriptArgs[1] : '';

function fail(msg) {
  std.err.puts('FAIL [' + scenario + '] ' + msg + '\n');
  std.exit(1);
}

function check(cond, msg) {
  if (!cond) fail(msg);
}

function load(name) {
  (0, eval)(std.loadFile(ROOT + '/js/' + name));
}

function handlerNames() {
  return globalThis.statum._bridge.attributeHandlers.map(function (h) { return h.name; });
}

installShim();
var log = globalThis.__shim.log;

if (scenario === '1') {
  load('statum-core.js');
  var s = globalThis.statum;
  check(s, 'window.statum is not defined');
  check(s.version === '0.1.0', 'version missing');
  check(typeof s.config === 'object' && s.config.entrypointUrl === '/_statum/entrypoint',
    'config missing');
  check(typeof s.registerAttribute === 'function', 'registerAttribute is not a function');
  check(s._bridge, '_bridge is not present');
  check(typeof s.Error === 'function', 'statum.Error missing');
  check(log.errors.length === 0, 'unexpected console.error at load: ' + JSON.stringify(log.errors));
  check(log.warns.length === 0, 'unexpected console.warn at load: ' + JSON.stringify(log.warns));

  // The three override pairs round-trip a function and null out non-functions.
  var fn = function () {};
  var pairs = ['onConfirmHandler', 'onNotifyHandler', 'onErrorHandler'];
  pairs.forEach(function (p) {
    s[p] = fn;
    check(s[p] === fn, p + ' did not round-trip the function');
    s[p] = 42;
    check(s[p] === null, p + ' did not null out a non-function');
    s[p] = 'nope';
    check(s[p] === null, p + ' did not null out a non-function (string)');
  });

  // No render driver installed: a render cycle must not crash.
  check(s._bridge.attributeHandlers.length === 0, 'handlers registered without modules');
  s._bridge.renderAll();
  check(log.errors.length === 0, 'renderAll without a driver errored: ' + JSON.stringify(log.errors));

} else if (scenario === '2') {
  load('statum-core.js');
  load('statum-document.js');
  var s = globalThis.statum;
  var names = handlerNames();
  check(JSON.stringify(names) === JSON.stringify(
    ['stm-class.', 'stm-attribute.', 'stm-disabled', 'stm-text', 'stm-html']),
    'handler order is ' + JSON.stringify(names));

  // The driver is installed: renderAll walks document.body and applies a
  // binding. Scope comes from the (empty) store, so use a literal expression.
  var el = globalThis.__shim.makeElement('p');
  el.setAttribute('stm-text', "'driven'");
  globalThis.__shim.body.appendChild(el);
  s._bridge.renderAll();
  check(el.textContent === 'driven',
    'render driver did not apply stm-text (got ' + JSON.stringify(el.textContent) + ')');
  check(log.errors.length === 0, 'unexpected console.error: ' + JSON.stringify(log.errors));

} else if (scenario === '3') {
  load('statum-core.js');
  load('statum-document.js');
  load('statum-markdown.js');
  var s = globalThis.statum;
  var names = handlerNames();
  check(JSON.stringify(names) === JSON.stringify(
    ['stm-class.', 'stm-attribute.', 'stm-disabled', 'stm-text', 'stm-html',
     'stm-markdown', 'stm-h-demotion']),
    'full handler order is ' + JSON.stringify(names));
  // "directly after" from the ordered list above.
  check(names.indexOf('stm-markdown') === names.indexOf('stm-html') + 1,
    'stm-markdown is not directly after stm-html');
  check(names.indexOf('stm-h-demotion') === names.indexOf('stm-markdown') + 1,
    'stm-h-demotion is not directly after stm-markdown');

  // Programmatic API shares the binding's engine. The engine renders blocks
  // with a trailing newline (CommonMark serialisation), so '# x' -> '<h1>x</h1>\n'.
  check(s.markdown, 'statum.markdown is not defined');
  check(s.markdown.render('# x') === '<h1>x</h1>\n',
    'markdown.render("# x") = ' + JSON.stringify(s.markdown.render('# x')));
  check(typeof s.markdown.renderTo === 'function', 'markdown.renderTo is not a function');
  var el = globalThis.__shim.makeElement('div');
  s.markdown.renderTo(el, '# y');
  check(el.innerHTML === '<h1>y</h1>\n',
    'renderTo innerHTML = ' + JSON.stringify(el.innerHTML));
  // The binding path and the programmatic path agree. (Attribute values are
  // expressions, hence the quoted string; an unparseable value yields
  // undefined and leaves the element untouched by design.)
  el.innerHTML = '';
  el.setAttribute('stm-markdown', "'# y'");
  globalThis.__shim.body.appendChild(el);
  // Drive the walk through the driver via a fresh render cycle.
  var bridge = s._bridge;
  bridge.renderAll();
  check(el.innerHTML === '<h1>y</h1>\n',
    'stm-markdown binding innerHTML = ' + JSON.stringify(el.innerHTML));

  // Test hatch (the shim sets __STATUM_TEST__).
  check(typeof s._testMarkdown === 'function', '_testMarkdown is not exposed');
  check(log.errors.length === 0, 'unexpected console.error: ' + JSON.stringify(log.errors));

} else if (scenario === '4') {
  // Cherry-pick: markdown without the walk module. 'after: stm-html' cannot
  // resolve (document is absent) so it warns and keeps registration order —
  // that is the designed degradation, not a failure.
  load('statum-core.js');
  load('statum-markdown.js');
  var s = globalThis.statum;
  check(s.markdown.render('# x') === '<h1>x</h1>\n', 'markdown.render failed without statum-document.js');
  var names = handlerNames();
  check(names.indexOf('stm-markdown') !== -1 && names.indexOf('stm-h-demotion') !== -1,
    'handlers not registered: ' + JSON.stringify(names));
  check(names.indexOf('stm-h-demotion') === names.indexOf('stm-markdown') + 1,
    'demotion constraint broke without the walk: ' + JSON.stringify(names));
  check(log.errors.length === 0, 'unexpected console.error: ' + JSON.stringify(log.errors));
  check(log.warns.length === 1 && log.warns[0].indexOf('stm-html') !== -1,
    'expected one unresolvable-constraint warning, got ' + JSON.stringify(log.warns));
  // A render cycle with no driver still runs.
  s._bridge.renderAll();
  check(log.errors.length === 0, 'renderAll errored without a driver: ' + JSON.stringify(log.errors));

} else if (scenario === '5') {
  // document without core: the guarded IIFE must record one console.error,
  // not throw, and attach nothing.
  load('statum-document.js');
  check(log.errors.length === 1, 'expected exactly one console.error, got ' + JSON.stringify(log.errors));
  check(log.errors[0].indexOf('statum-document.js requires statum-core.js') !== -1,
    'error message: ' + JSON.stringify(log.errors[0]));
  check(!globalThis.statum, 'document attached window.statum without core');
  // Same for markdown.
  log.errors.length = 0;
  load('statum-markdown.js');
  check(log.errors.length === 1, 'expected one console.error from markdown, got ' + JSON.stringify(log.errors));
  check(log.errors[0].indexOf('statum-markdown.js requires statum-core.js') !== -1,
    'error message: ' + JSON.stringify(log.errors[0]));
  check(!globalThis.statum, 'markdown attached window.statum without core');

} else if (scenario === '6') {
  load('statum-core.js');
  load('statum-document.js');
  var before = handlerNames();
  globalThis.statum.registerAttribute('stm-text', function () {});
  check(log.warns.length === 1, 'double registration did not warn: ' + JSON.stringify(log.warns));
  check(log.warns[0].indexOf('already registered') !== -1, 'warn text: ' + JSON.stringify(log.warns[0]));
  var after = handlerNames();
  check(JSON.stringify(before) === JSON.stringify(after),
    'order changed on double registration: ' + JSON.stringify(after));

} else if (scenario === '7') {
  load('statum-core.js');
  load('statum-document.js');
  var before = handlerNames();
  globalThis.statum.registerAttribute('stm-prefill', function () {}, { after: 'stm-nope' });
  check(log.warns.length === 1, 'unresolvable constraint did not warn: ' + JSON.stringify(log.warns));
  check(log.warns[0].indexOf('stm-nope') !== -1, 'warn names the missing anchor: ' + JSON.stringify(log.warns[0]));
  var after = handlerNames();
  check(after.length === before.length + 1, 'handler was not registered');
  check(after[after.length - 1] === 'stm-prefill',
    'handler did not keep registration position: ' + JSON.stringify(after));

} else {
  fail('unknown scenario: ' + scenario);
}

print('scenario ' + scenario + ': OK');