local createLibTest = require('/apis/libtest');
local createAi = require('/apis/libai');

local testlib = createLibTest({ ... });

local function fakeSettings(initial)
  local values = initial or {};
  local getCounts = {};
  local saveCount = 0;
  return {
    get = function(key)
      getCounts[key] = (getCounts[key] or 0) + 1;
      return values[key];
    end,
    set = function(key, value) values[key] = value; end,
    unset = function(key) values[key] = nil; end,
    save = function() saveCount = saveCount + 1; end,
    values = values,
    getCount = function(key) return getCounts[key] or 0; end,
    saveCount = function() return saveCount; end,
  };
end

local function fakeOs(computerId, computerLabel)
  return {
    getComputerID = function() return computerId; end,
    getComputerLabel = function() return computerLabel; end,
  };
end

local function response(code, body)
  return {
    getResponseCode = function() return code; end,
    readAll = function() return body; end,
    close = function() end,
  };
end

-- postResults: list of responses returned in order for each POST call.
-- getResults: list of responses returned in order for each GET call.
local function fakeHttp(postResults, getResults)
  postResults = postResults or {};
  getResults = getResults or {};
  local postCalls = {};
  local getCalls = {};
  local postIdx = 0;
  local getIdx = 0;
  return {
    post = function(req)
      local url, body, headers, timeout = req.url, req.body, req.headers, req.timeout;
      postCalls[#postCalls + 1] = { url = url, body = body, headers = headers, timeout = timeout };
      postIdx = postIdx + 1;
      local r = postResults[postIdx];
      if type(r) == 'function' then return r(url, body, headers); end
      return r;
    end,
    get = function(req)
      local url, headers, timeout = req.url, req.headers, req.timeout;
      getCalls[#getCalls + 1] = { url = url, headers = headers, timeout = timeout };
      getIdx = getIdx + 1;
      local r = getResults[getIdx];
      if type(r) == 'function' then return r(url, headers); end
      return r;
    end,
    postCalls = postCalls,
    getCalls = getCalls,
  };
end

local function httpError(code, body)
  return function()
    return nil, 'HTTP response code ' .. tostring(code), response(code, body);
  end;
end

local function sessionResp(id)
  return response(200, textutils.serializeJSON({ id = id, title = 'cc-ai' }));
end

local function messageResp(reply)
  return response(200, textutils.serializeJSON({
    info = { time = { completed = 1 } },
    parts = { { type = 'text', text = reply } },
  }));
end

local function postedText(call)
  local body = textutils.unserializeJSON(call.body);
  return body.parts[1].text;
end

-- base64 --

testlib.test('base64encode encodes simple ascii', function()
  -- "Man" -> "TWFu" is the canonical base64 test vector; tested indirectly via Authorization header
  local httpStub = fakeHttp(
    { sessionResp('ses_1'), messageResp('ok') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  settingsStub.values['opencc.password'] = 'pass';
  settingsStub.values['opencc.username'] = 'user';
  createAi({ http = httpStub, settings = settingsStub }).ask('hello');
  local auth = httpStub.postCalls[1].headers['Authorization'];
  -- base64('user:pass') = 'dXNlcjpwYXNz'
  testlib.assertEquals(auth, 'Basic dXNlcjpwYXNz');
end);

testlib.test('base64encode handles padding with one remainder byte', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_1'), messageResp('ok') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  settingsStub.values['opencc.password'] = 'x';
  settingsStub.values['opencc.username'] = 'a';
  createAi({ http = httpStub, settings = settingsStub }).ask('hello');
  -- base64('a:x') = 'YTp4'
  testlib.assertEquals(httpStub.postCalls[1].headers['Authorization'], 'Basic YTp4');
end);

-- listSessions --

testlib.test('listSessions returns newest sessions first', function()
  local sessions = {
    { id = 'ses_old', title = 'old', time = { updated = 10 } },
    { id = 'ses_created', title = 'created', time = { created = 20 } },
    { id = 'ses_new', title = 'new', time = { updated = 30 } },
    { id = 'ses_missing', title = 'missing' },
  };
  local httpStub = fakeHttp({}, { response(200, textutils.serializeJSON(sessions)) });
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.listSessions();

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(#result, 4);
  testlib.assertEquals(result[1].id, 'ses_new');
  testlib.assertEquals(result[2].id, 'ses_created');
  testlib.assertEquals(result[3].id, 'ses_old');
  testlib.assertEquals(result[4].id, 'ses_missing');
end);

testlib.test('listSessions logs session count when verbose', function()
  local sessions = {
    { id = 'ses_1', title = 'one', time = { updated = 10 } },
    { id = 'ses_2', title = 'two', time = { updated = 20 } },
  };
  local httpStub = fakeHttp({}, { response(200, textutils.serializeJSON(sessions)) });
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local logs = {};
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok = ai.listSessions({
    log = function(message) logs[#logs + 1] = message; end,
  });

  testlib.assertTrue(ok);
  testlib.assertTrue(string.find(logs[1], 'http://host', 1, true) ~= nil);
  testlib.assertEquals(logs[2], 'sessions returned: 2');
end);

testlib.test('listSessions sends configured directory query', function()
  local sessions = {
    { id = 'ses_1', title = 'one', time = { updated = 10 } },
  };
  local httpStub = fakeHttp({}, { response(200, textutils.serializeJSON(sessions)) });
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.directory'] = '/Users/garm/trap/cc-libs',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.listSessions();

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(#result, 1);
  testlib.assertEquals(httpStub.getCalls[1].url,
    'http://host/session?directory=%2FUsers%2Fgarm%2Ftrap%2Fcc-libs');
end);

testlib.test('listSessions caps HTTP timeout at one minute', function()
  local httpStub = fakeHttp({}, { response(200, '[]') });
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.timeout_seconds'] = 120,
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok = ai.listSessions();

  testlib.assertTrue(ok);
  testlib.assertEquals(httpStub.getCalls[1].timeout, 60);
end);

testlib.test('listSessions retries with persisted session directory when list is empty', function()
  local scopedSessions = {
    { id = 'ses_existing', title = 'existing', time = { updated = 20 } },
  };
  local session = {
    id = 'ses_existing',
    title = 'existing',
    directory = '/Users/garm/trap/cc-libs',
  };
  local httpStub = fakeHttp({}, {
    response(200, '[]'),
    response(200, textutils.serializeJSON(session)),
    response(200, textutils.serializeJSON(scopedSessions)),
  });
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_existing',
  });
  local logs = {};
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.listSessions({
    log = function(message) logs[#logs + 1] = message; end,
  });

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(#result, 1);
  testlib.assertEquals(result[1].id, 'ses_existing');
  testlib.assertEquals(httpStub.getCalls[1].url, 'http://host/session');
  testlib.assertEquals(httpStub.getCalls[2].url, 'http://host/session/ses_existing');
  testlib.assertEquals(httpStub.getCalls[3].url,
    'http://host/session?directory=%2FUsers%2Fgarm%2Ftrap%2Fcc-libs');
  testlib.assertTrue(string.find(logs[2], 'resolving directory', 1, true) ~= nil);
end);

testlib.test('listSessions fails when server_url missing', function()
  local httpStub = fakeHttp({}, {});
  local ai = createAi({ http = httpStub, settings = fakeSettings() });

  local ok, err = ai.listSessions();

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'opencc.server_url', 1, true) ~= nil);
  testlib.assertTrue(string.find(err, 'set opencc.server_url', 1, true) ~= nil);
  testlib.assertTrue(string.find(err, 'settings set', 1, true) == nil);
  testlib.assertEquals(#httpStub.getCalls, 0);
end);

testlib.test('listSessions fails when server unreachable', function()
  local httpStub = fakeHttp({}, { nil });
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.listSessions();

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'injoignable', 1, true) ~= nil);
end);

testlib.test('listSessions maps HTTP error response codes', function()
  local httpStub = fakeHttp({}, { httpError(401, '{}') });
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.listSessions();

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'HTTP 401', 1, true) ~= nil);
end);

-- ask --

testlib.test('ask creates session then sends message when no session_id', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_new'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host:4096' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.ask('hello');

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(result.reply, 'reply');
  testlib.assertEquals(result.sessionId, 'ses_new');
  testlib.assertEquals(#httpStub.postCalls, 2);
  testlib.assertTrue(string.find(httpStub.postCalls[1].url, '/session', 1, true) ~= nil);
  testlib.assertTrue(string.find(httpStub.postCalls[2].url, '/session/ses_new/message', 1, true) ~= nil);
end);

testlib.test('ask creates cc-ai titled sessions', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_new'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.title, 'cc-ai');
end);

testlib.test('ask saves new session_id to settings', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_abc'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  testlib.assertEquals(settingsStub.values['opencc.session_id'], 'ses_abc');
  testlib.assertEquals(settingsStub.saveCount(), 1);
end);

testlib.test('ask saves custom sessionSettingKey to settings', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_trapgpt'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello', { sessionSettingKey = 'trapgpt.opencc.session_id' });

  testlib.assertEquals(settingsStub.values['trapgpt.opencc.session_id'], 'ses_trapgpt');
  testlib.assertEquals(settingsStub.values['opencc.session_id'], nil);
  testlib.assertEquals(settingsStub.saveCount(), 1);
end);

testlib.test('ask reuses existing session_id without creating a new session', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_existing',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok = ai.ask('hello');

  testlib.assertTrue(ok);
  testlib.assertEquals(#httpStub.postCalls, 1);
  testlib.assertTrue(string.find(httpStub.postCalls[1].url, '/session/ses_existing/message', 1, true) ~= nil);
end);

testlib.test('ask reuses custom sessionSettingKey without creating a new session', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_other',
    ['trapgpt.opencc.session_id'] = 'ses_trapgpt',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok = ai.ask('hello', { sessionSettingKey = 'trapgpt.opencc.session_id' });

  testlib.assertTrue(ok);
  testlib.assertEquals(#httpStub.postCalls, 1);
  testlib.assertTrue(string.find(httpStub.postCalls[1].url, '/session/ses_trapgpt/message', 1, true) ~= nil);
end);

testlib.test('ask uses synchronous message endpoint by default', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_sync'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.ask('hello');

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(result.reply, 'reply');
  testlib.assertEquals(#httpStub.postCalls, 2);
  testlib.assertTrue(string.find(httpStub.postCalls[2].url, '/session/ses_sync/message', 1, true) ~= nil);
  testlib.assertTrue(string.find(httpStub.postCalls[2].url, 'prompt_async', 1, true) == nil);
  testlib.assertEquals(#httpStub.getCalls, 0);
end);

testlib.test('ask wraps prompt with caller context', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
  });
  local ai = createAi({
    http = httpStub,
    settings = settingsStub,
    os = fakeOs(42, 'storage-main'),
  });

  ai.ask('my prompt');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(#body.parts, 1);
  testlib.assertEquals(body.parts[1].type, 'text');
  testlib.assertTrue(string.find(body.parts[1].text, '<caller-context hidden="true">', 1, true) ~= nil);
  testlib.assertTrue(string.find(body.parts[1].text, 'computer id: 42', 1, true) ~= nil);
  testlib.assertTrue(string.find(body.parts[1].text, 'computer label: storage-main', 1, true) ~= nil);
  testlib.assertTrue(string.find(body.parts[1].text, 'User prompt:\nmy prompt', 1, true) ~= nil);
end);

testlib.test('ask omits blank caller label', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
  });
  local ai = createAi({
    http = httpStub,
    settings = settingsStub,
    os = fakeOs(7, ''),
  });

  ai.ask('my prompt');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertTrue(string.find(body.parts[1].text, 'computer id: 7', 1, true) ~= nil);
  testlib.assertEquals(string.find(body.parts[1].text, 'computer label:', 1, true), nil);
end);

testlib.test('ask includes agent from settings', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.agent'] = 'atm10-expert',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.agent, 'atm10-expert');
end);

testlib.test('ask option agent overrides settings', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.agent'] = 'build',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello', { agent = 'atm10-expert' });

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.agent, 'atm10-expert');
end);

testlib.test('ask omits blank agent setting', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.agent'] = '   ',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.agent, nil);
end);

testlib.test('ask includes variant when setting is set', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.variant'] = 'low',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.variant, 'low');
end);

testlib.test('ask omits blank variant setting', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.variant'] = '   ',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.variant, nil);
end);

testlib.test('ask includes model when provider_id and model_id are set', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.provider_id'] = 'anthropic',
    ['opencc.model_id'] = 'claude-opus-4-7',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.model.providerID, 'anthropic');
  testlib.assertEquals(body.model.modelID, 'claude-opus-4-7');
end);

testlib.test('ask omits model when provider_id is missing', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.model_id'] = 'claude-opus-4-7',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.model, nil);
end);

testlib.test('ask omits model when model_id is missing', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.provider_id'] = 'anthropic',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.model, nil);
end);

testlib.test('ask omits model when neither provider_id nor model_id is set', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.model, nil);
end);

testlib.test('ask options providerID/modelID override settings', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.provider_id'] = 'anthropic',
    ['opencc.model_id'] = 'claude-opus-4-7',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello', { providerID = 'openai', modelID = 'gpt-5' });

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.model.providerID, 'openai');
  testlib.assertEquals(body.model.modelID, 'gpt-5');
end);

testlib.test('ask options variant overrides setting', function()
  local httpStub = fakeHttp(
    { messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
    ['opencc.variant'] = 'high',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello', { variant = 'low' });

  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.variant, 'low');
end);

testlib.test('ask uses one minute HTTP timeout by default', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_1'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok = ai.ask('hello');

  testlib.assertTrue(ok);
  testlib.assertEquals(httpStub.postCalls[1].timeout, 60);
  testlib.assertEquals(httpStub.postCalls[2].timeout, 60);
end);

testlib.test('ask caps per-call HTTP timeout at one minute', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_1'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.timeout_seconds'] = 500,
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok = ai.ask('hello');

  testlib.assertTrue(ok);
  testlib.assertEquals(httpStub.postCalls[1].timeout, 60);
  testlib.assertEquals(httpStub.postCalls[2].timeout, 60);
end);

testlib.test('ask rejects missing prompt without HTTP calls', function()
  local httpStub = fakeHttp({}, {});
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask();

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'missing prompt', 1, true) ~= nil);
  testlib.assertEquals(#httpStub.postCalls, 0);
  testlib.assertEquals(#httpStub.getCalls, 0);
end);

testlib.test('ask rejects blank prompt without HTTP calls', function()
  local httpStub = fakeHttp({}, {});
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask('   ');

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'missing prompt', 1, true) ~= nil);
  testlib.assertEquals(#httpStub.postCalls, 0);
  testlib.assertEquals(#httpStub.getCalls, 0);
end);

testlib.test('ask concatenates multiple text parts', function()
  local httpStub = fakeHttp(
    { response(200, textutils.serializeJSON({
        info = {},
        parts = {
          { type = 'step-start' },
          { type = 'text', text = 'hello ' },
          { type = 'tool-call' },
          { type = 'text', text = 'world' },
        },
      })) },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.ask('hello');

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(result.reply, 'hello world');
end);

testlib.test('ask fails with missing server_url', function()
  local httpStub = fakeHttp({}, {});
  local ai = createAi({ http = httpStub, settings = fakeSettings() });

  local ok, err = ai.ask('hello');

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'opencc.server_url', 1, true) ~= nil);
  testlib.assertTrue(string.find(err, 'set opencc.server_url', 1, true) ~= nil);
  testlib.assertTrue(string.find(err, 'settings set', 1, true) == nil);
  testlib.assertEquals(#httpStub.postCalls, 0);
end);

testlib.test('ask fails when server unreachable on session create', function()
  local httpStub = fakeHttp({ nil }, {});
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask('hello');

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'injoignable', 1, true) ~= nil);
end);

testlib.test('ask fails when server unreachable on message send', function()
  local httpStub = fakeHttp({ sessionResp('ses_1'), nil }, {});
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask('hello');

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'injoignable', 1, true) ~= nil);
end);

testlib.test('ask maps 401 on message send', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_1'), response(401, '{}') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask('hello');

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'HTTP 401', 1, true) ~= nil);
end);

testlib.test('ask maps HTTP error response on message send', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_1'), httpError(401, '{}') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask('hello');

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'HTTP 401', 1, true) ~= nil);
end);

testlib.test('ask on 404 clears session_id and suggests ai new', function()
  local httpStub = fakeHttp(
    { response(404, '{}') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_stale',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask('hello');

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'ai new', 1, true) ~= nil);
  testlib.assertEquals(settingsStub.values['opencc.session_id'], nil);
end);

testlib.test('ask on HTTP error 404 clears session_id', function()
  local httpStub = fakeHttp(
    { httpError(404, '{}') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_stale',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask('hello');

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'ai new', 1, true) ~= nil);
  testlib.assertEquals(settingsStub.values['opencc.session_id'], nil);
end);

testlib.test('ask persist=false creates a session without saving session_id', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_ephemeral'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_persisted',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.ask('hello', { persist = false });

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(result.sessionId, 'ses_ephemeral');
  testlib.assertEquals(settingsStub.values['opencc.session_id'], 'ses_persisted');
  testlib.assertEquals(settingsStub.getCount('opencc.session_id'), 0);
  testlib.assertEquals(settingsStub.saveCount(), 0);
  testlib.assertEquals(#httpStub.postCalls, 2);
  testlib.assertTrue(string.find(httpStub.postCalls[1].url, '/session', 1, true) ~= nil);
end);

testlib.test('ask persist=false does not clear session_id on 404', function()
  local httpStub = fakeHttp(
    { response(404, '{}') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_persisted',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, err = ai.ask('hello', { persist = false, sessionId = 'ses_missing' });

  testlib.assertTrue(not ok);
  testlib.assertTrue(string.find(err, 'session introuvable', 1, true) ~= nil);
  testlib.assertEquals(settingsStub.values['opencc.session_id'], 'ses_persisted');
  testlib.assertEquals(settingsStub.getCount('opencc.session_id'), 0);
  testlib.assertEquals(settingsStub.saveCount(), 0);
end);

testlib.test('ask omits Authorization header when no password', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_1'), messageResp('reply') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  ai.ask('hello');

  testlib.assertEquals(httpStub.postCalls[1].headers['Authorization'], nil);
end);

-- lua executor --

testlib.test('lua executor captures print write and returned values', function()
  local ai = createAi({ http = fakeHttp({}, {}), settings = fakeSettings() });
  local executor = ai.createLuaExecutor({ live = false, luaTimeoutSeconds = false });

  local ok, output, kind = executor('print("hello", "world")\nwrite("x")\nreturn 7, "z"');

  testlib.assertTrue(ok, tostring(output));
  testlib.assertEquals(kind, nil);
  testlib.assertEquals(output, 'hello\tworld\nx\n7\tz\n');
end);

testlib.test('lua executor classifies syntax and identifier errors', function()
  local ai = createAi({ http = fakeHttp({}, {}), settings = fakeSettings() });
  local executor = ai.createLuaExecutor({ live = false, luaTimeoutSeconds = false });

  local syntaxOk, _, syntaxKind = executor('if true then');
  local identifierOk, identifierErr, identifierKind = executor('definitely_missing()');

  testlib.assertTrue(not syntaxOk);
  testlib.assertEquals(syntaxKind, 'syntax');
  testlib.assertTrue(not identifierOk);
  testlib.assertEquals(identifierKind, 'identifier');
  testlib.assertTrue(string.find(identifierErr, 'nil', 1, true) ~= nil);
end);

testlib.test('lua executor classifies non-identifier runtime errors as other', function()
  local ai = createAi({ http = fakeHttp({}, {}), settings = fakeSettings() });
  local executor = ai.createLuaExecutor({ live = false, luaTimeoutSeconds = false });

  local ok, err, kind = executor('error("boom")');

  testlib.assertTrue(not ok);
  testlib.assertEquals(kind, 'other');
  testlib.assertTrue(string.find(err, 'boom', 1, true) ~= nil);
end);

-- luaExec --

testlib.test('luaExec succeeds on first attempt and sends output for final reply', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_lua'), messageResp('print("hello")'), messageResp('final reply') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_persisted',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });
  local execCalls = {};

  local ok, result = ai.luaExec('say hello', {
    executor = function(code)
      execCalls[#execCalls + 1] = code;
      return true, 'hello\n', nil;
    end,
  });

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(result.reply, 'final reply');
  testlib.assertEquals(result.output, 'hello\n');
  testlib.assertEquals(result.attempts, 1);
  testlib.assertEquals(#execCalls, 1);
  testlib.assertEquals(settingsStub.values['opencc.session_id'], 'ses_persisted');
  testlib.assertEquals(settingsStub.getCount('opencc.session_id'), 0);
  testlib.assertEquals(settingsStub.saveCount(), 0);
  testlib.assertEquals(#httpStub.postCalls, 3);

  local sessionBody = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(sessionBody.title, 'cc-ai lua-exec');
  testlib.assertTrue(string.find(postedText(httpStub.postCalls[2]), 'raw Lua code only', 1, true) ~= nil);
  testlib.assertTrue(string.find(postedText(httpStub.postCalls[2]), 'say hello', 1, true) ~= nil);
  testlib.assertTrue(string.find(postedText(httpStub.postCalls[3]), 'Lua output:', 1, true) ~= nil);
  testlib.assertTrue(string.find(postedText(httpStub.postCalls[3]), 'natural language', 1, true) ~= nil);
  testlib.assertTrue(string.find(postedText(httpStub.postCalls[3]), 'hello', 1, true) ~= nil);
end);

testlib.test('luaExec retries on identifier error and succeeds', function()
  local httpStub = fakeHttp(
    {
      sessionResp('ses_lua'),
      messageResp('fo0()'),
      messageResp('print("fixed")'),
      messageResp('fixed reply'),
    },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });
  local execCalls = 0;

  local ok, result = ai.luaExec('fix name', {
    executor = function()
      execCalls = execCalls + 1;
      if execCalls == 1 then
        return false, 'attempt to call a nil value (global "fo0")', 'identifier';
      end
      return true, 'fixed\n', nil;
    end,
  });

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(result.reply, 'fixed reply');
  testlib.assertEquals(result.attempts, 2);
  testlib.assertEquals(execCalls, 2);
  testlib.assertEquals(#httpStub.postCalls, 4);
  testlib.assertTrue(string.find(postedText(httpStub.postCalls[3]), 'Error kind: identifier', 1, true) ~= nil);
  testlib.assertTrue(string.find(postedText(httpStub.postCalls[3]), 'fo0()', 1, true) ~= nil);
end);

testlib.test('luaExec retries on syntax error and succeeds', function()
  local httpStub = fakeHttp(
    {
      sessionResp('ses_lua'),
      messageResp('if true then'),
      messageResp('print("ok")'),
      messageResp('ok reply'),
    },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });
  local execCalls = 0;

  local ok, result = ai.luaExec('write code', {
    executor = function()
      execCalls = execCalls + 1;
      if execCalls == 1 then
        return false, "'end' expected", 'syntax';
      end
      return true, 'ok\n', nil;
    end,
    maxRetries = 1,
  });

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(result.reply, 'ok reply');
  testlib.assertEquals(result.attempts, 2);
  testlib.assertEquals(execCalls, 2);
  testlib.assertEquals(#httpStub.postCalls, 4);
  testlib.assertTrue(string.find(postedText(httpStub.postCalls[3]), 'Error kind: syntax', 1, true) ~= nil);
end);

testlib.test('luaExec aborts on non-identifier runtime error', function()
  local httpStub = fakeHttp(
    { sessionResp('ses_lua'), messageResp('peripheral.wrap("left").call()') },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.luaExec('use peripheral', {
    executor = function()
      return false, 'peripheral not present', 'other';
    end,
  });

  testlib.assertTrue(not ok);
  testlib.assertEquals(result.error, 'peripheral not present');
  testlib.assertEquals(result.errorKind, 'other');
  testlib.assertEquals(result.attempts, 1);
  testlib.assertEquals(#httpStub.postCalls, 2);
end);

testlib.test('luaExec exhausts retry budget', function()
  local httpStub = fakeHttp(
    {
      sessionResp('ses_lua'),
      messageResp('bad1()'),
      messageResp('bad2()'),
      messageResp('bad3()'),
    },
    {}
  );
  local settingsStub = fakeSettings({ ['opencc.server_url'] = 'http://host' });
  local ai = createAi({ http = httpStub, settings = settingsStub });
  local execCalls = 0;

  local ok, result = ai.luaExec('keep failing', {
    executor = function()
      execCalls = execCalls + 1;
      return false, 'attempt to call a nil value (global "bad")', 'identifier';
    end,
    maxRetries = 2,
  });

  testlib.assertTrue(not ok);
  testlib.assertEquals(result.errorKind, 'identifier');
  testlib.assertEquals(result.attempts, 3);
  testlib.assertTrue(result.retryExhausted);
  testlib.assertEquals(execCalls, 3);
  testlib.assertEquals(#httpStub.postCalls, 4);
end);

-- ping --

testlib.test('ping sends pong prompt', function()
  local httpStub = fakeHttp(
    { messageResp('pong') },
    {}
  );
  local settingsStub = fakeSettings({
    ['opencc.server_url'] = 'http://host',
    ['opencc.session_id'] = 'ses_1',
  });
  local ai = createAi({ http = httpStub, settings = settingsStub });

  local ok, result = ai.ping();

  testlib.assertTrue(ok, tostring(result));
  testlib.assertEquals(result.reply, 'pong');
  local body = textutils.unserializeJSON(httpStub.postCalls[1].body);
  testlib.assertEquals(body.parts[1].text, 'reply with exactly: pong');
end);

-- clearSession --

testlib.test('clearSession unsets persisted session id', function()
  local settingsStub = fakeSettings({ ['opencc.session_id'] = 'ses_old' });
  local ai = createAi({ http = fakeHttp({}, {}), settings = settingsStub });

  ai.clearSession();

  testlib.assertEquals(settingsStub.values['opencc.session_id'], nil);
  testlib.assertEquals(settingsStub.saveCount(), 1);
end);

testlib.test('clearSession unsets custom sessionSettingKey', function()
  local settingsStub = fakeSettings({
    ['opencc.session_id'] = 'ses_old',
    ['trapgpt.opencc.session_id'] = 'ses_trapgpt',
  });
  local ai = createAi({ http = fakeHttp({}, {}), settings = settingsStub });

  ai.clearSession({ sessionSettingKey = 'trapgpt.opencc.session_id' });

  testlib.assertEquals(settingsStub.values['opencc.session_id'], 'ses_old');
  testlib.assertEquals(settingsStub.values['trapgpt.opencc.session_id'], nil);
  testlib.assertEquals(settingsStub.saveCount(), 1);
end);

testlib.run();
