import { app } from 'electron';
import * as fs from 'fs';
import * as path from 'path';

export interface DesktopSettings {
  hardwareAcceleration: boolean;
  vaapiVideoEncode: boolean;
}

export interface DesktopSettingsSnapshot extends DesktopSettings {
  runtimeHardwareAcceleration: boolean;
  restartRequired: boolean;
}

const DEFAULT_DESKTOP_SETTINGS: DesktopSettings = {
  hardwareAcceleration: true,
  vaapiVideoEncode: false
};

export function getDesktopSettingsSnapshot(): DesktopSettingsSnapshot {
  const storedSettings = readDesktopSettings();
  const runtimeHardwareAcceleration = app.isHardwareAccelerationEnabled();

  return {
    ...storedSettings,
    runtimeHardwareAcceleration,
    restartRequired: storedSettings.hardwareAcceleration !== runtimeHardwareAcceleration
  };
}

export function readDesktopSettings(): DesktopSettings {
  const filePath = getDesktopSettingsPath();

  try {
    if (!fs.existsSync(filePath)) {
      return { ...DEFAULT_DESKTOP_SETTINGS };
    }

    const raw = fs.readFileSync(filePath, 'utf8');
    const parsed = JSON.parse(raw) as Partial<DesktopSettings>;

    return {
      vaapiVideoEncode: typeof parsed.vaapiVideoEncode === 'boolean'
        ? parsed.vaapiVideoEncode
        : DEFAULT_DESKTOP_SETTINGS.vaapiVideoEncode,
      hardwareAcceleration: typeof parsed.hardwareAcceleration === 'boolean'
        ? parsed.hardwareAcceleration
        : DEFAULT_DESKTOP_SETTINGS.hardwareAcceleration
    };
  } catch {
    return { ...DEFAULT_DESKTOP_SETTINGS };
  }
}

export function updateDesktopSettings(patch: Partial<DesktopSettings>): DesktopSettingsSnapshot {
  const nextSettings: DesktopSettings = {
    ...readDesktopSettings(),
    ...patch
  };
  const filePath = getDesktopSettingsPath();

  fs.mkdirSync(path.dirname(filePath), { recursive: true });
  fs.writeFileSync(filePath, JSON.stringify(nextSettings, null, 2), 'utf8');

  return getDesktopSettingsSnapshot();
}

function getDesktopSettingsPath(): string {
  return path.join(app.getPath('userData'), 'desktop-settings.json');
}