/** @fileoverview COD-358 resizable vertical session rail policy and wiring. */

import { readFileSync } from 'node:fs';
import { resolve } from 'node:path';
import vm from 'node:vm';
import { afterEach, describe, expect, it, vi } from 'vitest';

const publicDir = resolve(import.meta.dirname, '../src/web/public');
const readPublic = (name: string) => readFileSync(resolve(publicDir, name), 'utf8');
const indexHtml = readPublic('index.html');
const stylesCss = readPublic('styles.css');
const settingsJs = readPublic('settings-ui.js');
const appJs = readPublic('app.js');
const terminalUiJs = readPublic('terminal-ui.js');
const buildJs = readFileSync(resolve(import.meta.dirname, '../scripts/build.mjs'), 'utf8');

type RailPolicy = {
  DEFAULT_WIDTH: number;
  MIN_WIDTH: number;
  MAX_WIDTH: number;
  resolveWidth: (input?: Record<string, unknown>) => number;
  resolveKeyboardWidth: (input: Record<string, unknown>) => number | null;
};

function loadRailPolicy(): RailPolicy {
  const context = vm.createContext({ window: {}, globalThis: {} });
  vm.runInContext(readPublic('constants.js'), context, { filename: 'constants.js' });
  return (context.window as { CodemanTabRail: RailPolicy }).CodemanTabRail;
}

afterEach(() => vi.useRealTimers());

describe('tab rail width policy', () => {
  it('uses fixed storage bounds and separate viewport/terminal clamps', () => {
    const policy = loadRailPolicy();
    expect(policy.DEFAULT_WIDTH).toBe(256);
    expect(policy.MIN_WIDTH).toBe(208);
    expect(policy.MAX_WIDTH).toBe(360);
    expect(policy.resolveWidth()).toBe(256);
    expect(policy.resolveWidth({ width: 120 })).toBe(208);
    expect(policy.resolveWidth({ width: 900 })).toBe(360);
    expect(policy.resolveWidth({ width: 360, viewportWidth: 700 })).toBe(280);
    expect(policy.resolveWidth({ width: 360 })).toBe(360);
    expect(policy.resolveWidth({ width: 360, mainWidth: 700, minTerminalWidth: 400 })).toBe(300);
  });

  it('supports accessible keyboard steps and reset keys', () => {
    const policy = loadRailPolicy();
    const base = { currentWidth: 256, viewportWidth: 1600, mainWidth: 1200, minTerminalWidth: 400 };
    expect(policy.resolveKeyboardWidth({ ...base, key: 'ArrowLeft' })).toBe(248);
    expect(policy.resolveKeyboardWidth({ ...base, key: 'ArrowRight' })).toBe(264);
    expect(policy.resolveKeyboardWidth({ ...base, key: 'ArrowRight', shiftKey: true })).toBe(288);
    expect(policy.resolveKeyboardWidth({ ...base, key: 'Home' })).toBe(208);
    expect(policy.resolveKeyboardWidth({ ...base, key: 'End' })).toBe(360);
    expect(policy.resolveKeyboardWidth({ ...base, key: 'Enter' })).toBe(256);
    // Enter resets to the CALLER's effective default: a rich rail passes 320
    // (its unsized rendering width), so the reset cannot land it below the
    // 288px tight threshold the way a hardcoded 256 did.
    expect(policy.resolveKeyboardWidth({ ...base, key: 'Enter', defaultWidth: 320 })).toBe(320);
    expect(policy.resolveKeyboardWidth({ ...base, key: 'Escape' })).toBeNull();
  });
});

describe('tab rail resize wiring', () => {
  it('ships an accessible handle and width presets', () => {
    expect(indexHtml).toContain('id="tabRailResizeHandle"');
    expect(indexHtml).toContain('role="separator"');
    expect(indexHtml).toContain('aria-orientation="vertical"');
    expect(indexHtml).toContain('aria-valuemin="208"');
    expect(indexHtml).toContain('aria-valuemax="360"');
    expect(indexHtml).toContain('id="appSettingsTabRailWidth"');
    expect(indexHtml).toContain('<option value="208">Compact');
    expect(indexHtml).toContain('<option value="256">Default');
    expect(indexHtml).toContain('<option value="320">Wide');
    expect(indexHtml).toContain('<option value="360">Maximum');
  });

  it('keeps preferred width device-local and distinct from effective width', () => {
    expect(settingsJs).toMatch(/tabRailWidth:\s*256/);
    expect(settingsJs).toMatch(/tabRailWidth:\s*this\.readTabRailWidthSetting/);
    const displayKeys = settingsJs.slice(settingsJs.indexOf('const displayKeys = new Set(['));
    expect(displayKeys.slice(0, 1900)).toContain("'tabRailWidth'");
    const controller = readPublic('tab-rail-resize.js');
    expect(controller).toContain('_scheduleTabRailSettle(resolved, preferred)');
    expect(controller).toContain('_scheduleTabRailSettle(effective, preferred)');
    expect(controller).toContain('applyTabOrientation?.()');
    expect(controller).toContain('applyTabRailWidth({ persist: false })');
  });

  it('installs the controller before terminal creation and owns generic observer churn', () => {
    const controller = readPublic('tab-rail-resize.js');
    expect(indexHtml).toContain('<script defer src="tab-rail-resize.js"></script>');
    expect(appJs).toContain('this.initTabRailResize?.()');
    expect(controller).toContain('setPointerCapture');
    expect(controller).toContain("addEventListener('lostpointercapture'");
    expect(controller).toContain('_tabRailResizeWatchdog');
    expect(terminalUiJs).toMatch(/if \(this\._tabRailResizeOwnsObserver\) return/);
    expect(buildJs).toContain("run('minify tab-rail-resize.js'");
    expect(buildJs).toMatch(/HASHABLE[\s\S]{0,1000}'tab-rail-resize\.js'/);
  });

  it('coalesces effective changes while persisting the preferred width', async () => {
    vi.useFakeTimers();
    const controller = readPublic('tab-rail-resize.js');
    class FakeCodemanApp {}
    const context = vm.createContext({
      CodemanApp: FakeCodemanApp,
      window: {},
      document: { querySelector: () => null },
      console,
      clearTimeout,
      setTimeout,
    });
    vm.runInContext(controller, context, { filename: 'tab-rail-resize.js' });
    const app = new FakeCodemanApp() as FakeCodemanApp & Record<string, any>;
    app.activeSessionId = 'session-1';
    app.sendResize = vi.fn(async () => true);
    app._persistTabRailWidth = vi.fn();
    app._tabRailResizeOwnsObserver = true;

    app._scheduleTabRailSettle(280, 360);
    app._scheduleTabRailSettle(300, 360);
    await vi.advanceTimersByTimeAsync(150);
    expect(app._persistTabRailWidth).toHaveBeenCalledOnce();
    expect(app._persistTabRailWidth).toHaveBeenCalledWith(360);
    expect(app.sendResize).toHaveBeenCalledOnce();
    expect(app._tabRailResizeOwnsObserver).toBe(false);
  });

  it('re-runs the wrap pass when the compact threshold flips, without double-rendering', () => {
    const controller = readPublic('tab-rail-resize.js');
    class FakeCodemanApp {}
    const classes = new Set<string>();
    const context = vm.createContext({
      CodemanApp: FakeCodemanApp,
      window: { CodemanTabRail: loadRailPolicy() },
      document: {
        documentElement: {
          style: { setProperty: () => {} },
          classList: {
            contains: (c: string) => classes.has(c),
            toggle: (c: string, force: boolean) => {
              if (force) classes.add(c);
              else classes.delete(c);
              return force;
            },
          },
        },
        getElementById: () => null,
        querySelector: () => null,
      },
      console,
      clearTimeout,
      setTimeout,
    });
    vm.runInContext(controller, context, { filename: 'tab-rail-resize.js' });
    const app = new FakeCodemanApp() as FakeCodemanApp & Record<string, any>;
    app._getTabRailBounds = () => ({});
    app.syncTabRailWidthSetting = vi.fn();
    app._fullRenderSessionTabs = vi.fn();

    // Rich rail dragged below 240px: applyTabWrapSettings() owns the folder
    // line and reads the compact class this call just toggled, so it must be
    // re-consulted on the flip — and when its own conditional render fires
    // (the folder flag changed), the explicit render must not double it.
    app._tallTabsEnabled = true;
    app.applyTabWrapSettings = vi.fn(() => {
      app._tallTabsEnabled = false;
      app._fullRenderSessionTabs();
    });
    app._setTabRailWidth(210);
    expect(app.applyTabWrapSettings).toHaveBeenCalledOnce();
    expect(app._fullRenderSessionTabs).toHaveBeenCalledOnce();

    // Flip back up with an unchanged folder flag (simple-detail rail): the
    // explicit render must still fire — the compact row-action affordance
    // changed even though the wrap pass rendered nothing.
    app.applyTabWrapSettings = vi.fn();
    app._fullRenderSessionTabs = vi.fn();
    app._setTabRailWidth(300);
    expect(app.applyTabWrapSettings).toHaveBeenCalledOnce();
    expect(app._fullRenderSessionTabs).toHaveBeenCalledOnce();
  });

  it('keeps resize-observer ownership for pointer drags longer than the watchdog', async () => {
    vi.useFakeTimers();
    const controller = readPublic('tab-rail-resize.js');
    class FakeCodemanApp {}
    let resizing = true;
    const context = vm.createContext({
      CodemanApp: FakeCodemanApp,
      window: {},
      document: {
        body: { classList: { contains: (name: string) => name === 'tab-rail-resizing' && resizing } },
        querySelector: () => null,
      },
      console,
      clearTimeout,
      setTimeout,
    });
    vm.runInContext(controller, context, { filename: 'tab-rail-resize.js' });
    const app = new FakeCodemanApp() as FakeCodemanApp & Record<string, any>;

    app._claimTabRailResize();
    await vi.advanceTimersByTimeAsync(1100);
    expect(app._tabRailResizeOwnsObserver).toBe(true);

    resizing = false;
    await vi.advanceTimersByTimeAsync(1000);
    expect(app._tabRailResizeOwnsObserver).toBe(false);
  });

  it('keeps a viewport-clamped effective width out of the preferred-width control', () => {
    const controller = readPublic('tab-rail-resize.js');
    class FakeCodemanApp {}
    const values = new Map<string, string>();
    const rootClasses = new Set<string>();
    const custom = { textContent: 'Custom' };
    const select = {
      value: '360',
      dataset: { currentWidth: '360' },
      querySelector(selector: string) {
        if (selector === 'option[value="360"]') return {};
        if (selector === 'option[value="custom"]') return custom;
        return null;
      },
    };
    const handle = { setAttribute: vi.fn() };
    const document = {
      documentElement: {
        style: {
          getPropertyValue: (name: string) => values.get(name) ?? '',
          setProperty: (name: string, value: string) => values.set(name, value),
        },
        classList: {
          contains: (name: string) => rootClasses.has(name),
          toggle: (name: string, force: boolean) => (force ? rootClasses.add(name) : rootClasses.delete(name)),
        },
      },
      querySelector: (selector: string) => (selector === '.main' ? { clientWidth: 700 } : null),
      getElementById: (id: string) => {
        if (id === 'appSettingsTabRailWidth') return select;
        if (id === 'tabRailResizeHandle') return handle;
        return null;
      },
    };
    const context = vm.createContext({
      CodemanApp: FakeCodemanApp,
      window: { innerWidth: 700 },
      document,
      console,
      clearTimeout,
      setTimeout,
    });
    vm.runInContext(readPublic('constants.js'), context, { filename: 'constants.js' });
    vm.runInContext(controller, context, { filename: 'tab-rail-resize.js' });
    const app = new FakeCodemanApp() as FakeCodemanApp & Record<string, any>;
    app.loadAppSettingsFromStorage = () => ({ tabRailWidth: 360 });
    app.saveAppSettingsToStorage = vi.fn();

    expect(app.applyTabRailWidth({ persist: false })).toBe(280);
    expect(values.get('--tab-rail-width')).toBe('280px');
    expect(select.value).toBe('360');
    expect(select.dataset.currentWidth).toBe('360');
    expect(app.readTabRailWidthSetting()).toBe(360);
  });

  it('retains complete labels and clamps only the settled vertical presentation', () => {
    expect(appJs).toContain('class="tab-name-prefix"');
    const start = stylesCss.indexOf("html[data-tab-orientation='vertical'] .tab-rail .session-tab .tab-name");
    const rule = stylesCss.slice(start, start + 800);
    expect(rule).toContain('-webkit-line-clamp: 2');
    expect(rule).toContain('overflow-wrap: anywhere');
    expect(rule).toContain('white-space: normal');
  });

  it('closes detached rail menus before tab rebuilds and session cleanup', () => {
    const fullRenderStart = appJs.indexOf('  _fullRenderSessionTabs() {');
    const fullRender = appJs.slice(fullRenderStart, fullRenderStart + 250);
    const cleanupStart = appJs.indexOf('  _cleanupSessionData(sessionId) {');
    const cleanup = appJs.slice(cleanupStart, cleanupStart + 250);
    expect(fullRender).toContain('this.closeTabRailActionMenu?.()');
    expect(cleanup).toContain('this.closeTabRailActionMenu?.()');
  });
});