'use strict';

const test = require('node:test');
const assert = require('node:assert/strict');
const { buildDeviceTree, flattenVisibleRows } = require('../device-tree');
const { createInitialState, reduceSidebar, createSidebarController } = require('../sidebar-controller');

function fixture() {
  const model = buildDeviceTree({
    sites: [{ id: 's', name: 'Site' }],
    groups: [{ id: 'g', name: 'Group', parentId: 's' }],
    devices: [
      { id: 'a', name: 'Alpha', siteId: 's', deviceGroupId: 'g' },
      { id: 'b', name: 'Beta', siteId: 's', deviceGroupId: 'g' },
    ],
  });
  return model;
}

function visible(model, state) {
  return flattenVisibleRows(model, state);
}

function fixtureKeys(model) {
  const site = model.sites[0];
  const group = site.groups[0];
  const cameras = Object.fromEntries(group.cameras.map((camera) => [camera.canonicalId, camera.key]));
  return { site: site.key, group: group.key, cameras };
}

test('reducer expands, navigates, selects, collapses, and preserves hidden selection', () => {
  const model = fixture();
  const keys = fixtureKeys(model);
  let state = createInitialState();
  let rows = visible(model, state);
  state = reduceSidebar(state, { type: 'KEY', key: 'Home' }, rows);
  assert.equal(state.activeKey, keys.site);
  state = reduceSidebar(state, { type: 'KEY', key: 'ArrowRight' }, rows);
  assert.ok(state.expandedKeys.has(keys.site));

  rows = visible(model, state);
  state = reduceSidebar(state, { type: 'KEY', key: 'ArrowDown' }, rows);
  assert.equal(state.activeKey, keys.group);
  state = reduceSidebar(state, { type: 'KEY', key: 'ArrowRight' }, rows);
  rows = visible(model, state);
  state = reduceSidebar(state, { type: 'KEY', key: 'ArrowDown' }, rows);
  state = reduceSidebar(state, { type: 'KEY', key: 'Enter' }, rows);
  assert.equal(state.selectedKey, keys.cameras.a);

  state = reduceSidebar(state, { type: 'ACTIVATE', rowKey: keys.site }, rows);
  assert.equal(state.selectedKey, keys.cameras.a);
  assert.equal(visible(model, state).hiddenSelected, true);
});

test('keyboard Left/Right parent behavior, bounds, Space and Escape', () => {
  const model = fixture();
  const keys = fixtureKeys(model);
  let state = createInitialState({
    expandedKeys: new Set([keys.site, keys.group]),
    activeKey: keys.cameras.a,
    searchQuery: 'alpha',
  });
  let rows = visible(model, state);
  state = reduceSidebar(state, { type: 'KEY', key: 'ArrowLeft' }, rows);
  assert.equal(state.activeKey, keys.group);
  state = reduceSidebar(state, { type: 'KEY', key: 'ArrowLeft' }, rows);
  assert.equal(state.expandedKeys.has(keys.group), false);
  state = reduceSidebar(state, { type: 'KEY', key: 'End' }, visible(model, state));
  assert.equal(state.activeKey, keys.group);
  state = reduceSidebar(state, { type: 'KEY', key: ' ' }, visible(model, state));
  assert.equal(state.expandedKeys.has(keys.group), true);
  state = reduceSidebar(state, { type: 'KEY', key: 'Escape' }, visible(model, state));
  assert.equal(state.searchQuery, '');
});

test('malformed and unknown delegated row keys are no-ops', () => {
  const model = fixture();
  const state = createInitialState({ activeKey: fixtureKeys(model).site });
  const rows = visible(model, state);
  assert.equal(reduceSidebar(state, { type: 'ACTIVATE', rowKey: '__proto__' }, rows), state);
  assert.equal(reduceSidebar(state, { type: 'CLICK', rowKey: 'camera:not-there' }, rows), state);
});

test('controller commits exactly once per dispatch through view adapter', () => {
  const model = fixture();
  const keys = fixtureKeys(model);
  const commits = [];
  const view = { commit: (snapshot) => commits.push(snapshot) };
  const controller = createSidebarController({ model, view, rowHeight: 28, overscan: 3 });
  assert.equal(commits.length, 1);
  controller.dispatch({ type: 'ACTIVATE', rowKey: keys.site });
  assert.equal(commits.length, 2);
  assert.equal(commits[1].state.expandedKeys.has(keys.site), true);
  assert.ok(Array.isArray(commits[1].window.rows));
  const modelReference = controller.getSnapshot().rows;
  controller.refresh();
  assert.equal(commits.length, 3);
  assert.notEqual(controller.getSnapshot().rows, modelReference);
  assert.equal(controller.getSnapshot().rows.length, modelReference.length);
});

test('active and selected state survive virtualization and selection is indicated when hidden', () => {
  const model = fixture();
  const keys = fixtureKeys(model);
  const commits = [];
  const controller = createSidebarController({ model, view: { commit: (value) => commits.push(value) } });
  controller.dispatch({ type: 'SET_SELECTION', rowKey: keys.cameras.b });
  controller.dispatch({ type: 'SET_VIEWPORT', scrollTop: 9999, viewportHeight: 20 });
  const snapshot = commits.at(-1);
  assert.equal(snapshot.state.selectedKey, keys.cameras.b);
  assert.equal(snapshot.rows.hiddenSelected, true);
});

test('controller search temporarily expands matches with one completion commit', async () => {
  const model = fixture();
  const keys = fixtureKeys(model);
  const commits = [];
  const scheduled = [];
  const controller = createSidebarController({
    model,
    view: { commit: (value) => commits.push(value) },
    scheduler: (work) => scheduled.push(work),
    chunkSize: 1,
  });
  const pending = controller.search('beta group');
  while (scheduled.length) scheduled.shift()();
  const result = await pending;
  assert.equal(result.count, 1);
  assert.equal(commits.length, 2);
  assert.deepEqual(commits.at(-1).rows.map((row) => row.key), [keys.site, keys.group, keys.cameras.b]);
  assert.equal(controller.getState().expandedKeys.size, 0);
});

test('first arrow press chooses the directional edge when no row is active', () => {
  const model = buildDeviceTree({
    sites: [{ id: 'b', name: 'B' }, { id: 'a', name: 'A' }, { id: 'c', name: 'C' }],
  });
  const rows = visible(model, createInitialState());
  assert.equal(reduceSidebar(createInitialState(), { type: 'KEY', key: 'ArrowDown' }, rows).activeKey, rows[0].key);
  assert.equal(reduceSidebar(createInitialState(), { type: 'KEY', key: 'ArrowUp' }, rows).activeKey, rows.at(-1).key);
});

test('manual viewport scrolling may virtualize selection until keyboard navigation restores the active row', () => {
  const model = buildDeviceTree({
    sites: [{ id: 'large', name: 'Large' }],
    groups: [],
    devices: Array.from({ length: 1500 }, (_, index) => ({
      id: `c${String(index).padStart(4, '0')}`,
      name: `Camera ${String(index).padStart(4, '0')}`,
      siteId: 'large',
    })),
  });
  const site = model.sites[0];
  const group = site.groups[0];
  const firstCamera = group.cameras[0];
  const controller = createSidebarController({
    model,
    view: { commit() {} },
    rowHeight: 20,
    overscan: 0,
    initialState: { expandedKeys: new Set([site.key, group.key]), viewportHeight: 100 },
  });

  controller.dispatch({ type: 'SET_SELECTION', rowKey: firstCamera.key });
  controller.dispatch({ type: 'SET_VIEWPORT', scrollTop: 30000, viewportHeight: 100 });
  let snapshot = controller.getSnapshot();
  assert.equal(snapshot.state.selectedKey, firstCamera.key);
  assert.equal(snapshot.state.activeKey, firstCamera.key);
  assert.equal(snapshot.state.scrollTop, 29940);
  assert.equal(snapshot.window.rows.some((row) => row.key === firstCamera.key), false);
  assert.equal(snapshot.rows.hiddenSelected, false);

  controller.dispatch({ type: 'KEY', key: 'Home' });
  snapshot = controller.getSnapshot();
  assert.equal(snapshot.state.activeKey, site.key);
  assert.equal(snapshot.state.scrollTop, 0);
  assert.equal(snapshot.window.rows.some((row) => row.key === site.key), true);
});

test('collapse clamps stale scroll and keyboard navigation scrolls active rows into the virtual window', () => {
  const model = buildDeviceTree({
    sites: [{ id: 'large', name: 'Large' }],
    groups: [],
    devices: Array.from({ length: 500 }, (_, index) => ({ id: `c${index}`, name: `Camera ${index}`, siteId: 'large' })),
  });
  const site = model.sites[0];
  const group = site.groups[0];
  const controller = createSidebarController({
    model,
    view: { commit() {} },
    rowHeight: 20,
    overscan: 0,
    initialState: { expandedKeys: new Set([site.key, group.key]), scrollTop: 10000, viewportHeight: 100 },
  });

  controller.dispatch({ type: 'ACTIVATE', rowKey: site.key });
  let snapshot = controller.getSnapshot();
  assert.deepEqual(snapshot.window.rows.map((row) => row.key), [site.key]);
  assert.equal(snapshot.state.scrollTop, 0);

  controller.dispatch({ type: 'ACTIVATE', rowKey: site.key });
  controller.dispatch({ type: 'SET_ACTIVE', rowKey: site.key });
  controller.dispatch({ type: 'KEY', key: 'End' });
  snapshot = controller.getSnapshot();
  assert.equal(snapshot.window.rows.some((row) => row.key === snapshot.state.activeKey), true);
  assert.ok(snapshot.state.scrollTop > 0);
});

test('search expansion controls rendered temporary state and restores saved expansion', async () => {
  const model = fixture();
  const scheduled = [];
  const site = model.sites[0];
  const group = site.groups[0];
  const controller = createSidebarController({
    model,
    view: { commit() {} },
    scheduler: (work) => scheduled.push(work),
    initialState: { expandedKeys: new Set([site.key]) },
  });
  const pending = controller.search('alpha');
  while (scheduled.length) scheduled.shift()();
  await pending;

  controller.dispatch({ type: 'SET_ACTIVE', rowKey: group.key });
  controller.dispatch({ type: 'KEY', key: 'ArrowLeft' });
  assert.equal(controller.getState().searchExpandedKeys.has(group.key), false);
  assert.equal(controller.getSnapshot().rows.some((row) => row.kind === 'camera'), false);
  assert.deepEqual(controller.getState().expandedKeys, new Set([site.key]));

  controller.dispatch({ type: 'KEY', key: 'ArrowRight' });
  assert.equal(controller.getState().searchExpandedKeys.has(group.key), true);
  assert.equal(controller.getSnapshot().rows.some((row) => row.kind === 'camera'), true);
  assert.deepEqual(controller.getState().expandedKeys, new Set([site.key]));

  await controller.search('');
  assert.deepEqual(controller.getState().expandedKeys, new Set([site.key]));
  assert.equal(controller.getState().searchExpandedKeys, null);
});