DMG Building

/**
 * Main DMG target class for building DMG files
 * Extends Target from app-builder-lib
 */
class DmgTarget extends Target {
  /** DMG configuration options from packager config */
  readonly options: DmgOptions;
  /** Indicates this target does not support async operations during build */
  readonly isAsyncSupported: boolean;
  
  /**
   * Create a new DMG target instance
   * @param packager - MacPackager instance for the build
   * @param outDir - Output directory for the generated DMG
   */
  constructor(packager: MacPackager, outDir: string);
  
  /**
   * Build the DMG file for the specified app and architecture
   * @param appPath - Path to the .app bundle to package
   * @param arch - Target architecture (x64, arm64, universal)
   * @returns Promise that resolves when DMG creation is complete
   */
  build(appPath: string, arch: Arch): Promise<void>;
  
  /**
   * Compute the volume name for the DMG
   * @param arch - Target architecture
   * @param custom - Optional custom volume name template with variable substitution
   * @returns Computed volume name string
   */
  computeVolumeName(arch: Arch, custom?: string | null): string;
  
  /**
   * Compute and validate DMG options from configuration
   * @param appPath - Path to the app bundle
   * @returns Promise resolving to validated DmgOptions
   */
  computeDmgOptions(appPath: string): Promise<DmgOptions>;
}

import { DmgTarget } from "dmg-builder";
import { MacPackager, Arch } from "app-builder-lib";

// Create packager and DMG target
const packager = new MacPackager(info, platform, cleanupTasks);
const dmgTarget = new DmgTarget(packager, "/output/directory");

// Build DMG for x64 architecture
await dmgTarget.build("/path/to/MyApp.app", Arch.x64);

// Custom volume name with variables
const volumeName = dmgTarget.computeVolumeName(
  Arch.x64, 
  "${productName} ${version} ${arch}"
);
// Result: "MyApp 1.0.0 x64"

/**
 * Compute the volume name for the DMG with variable substitution
 * @param arch - Target architecture for arch suffix
 * @param custom - Custom template with variables: ${arch}, ${shortVersion}, ${version}, ${name}, ${productName}
 * @returns Computed volume name
 */
computeVolumeName(arch: Arch, custom?: string | null): string;

/**
 * Compute and validate DMG options from packager configuration
 * Applies defaults for icon, background, format, and contents
 * @param appPath - Path to the app bundle for content configuration
 * @returns Promise resolving to complete DmgOptions configuration
 * @throws InvalidConfigurationError for invalid configuration combinations
 */
computeDmgOptions(appPath: string): Promise<DmgOptions>;

const dmgTarget = new DmgTarget(packager, outDir);
const options = await dmgTarget.computeDmgOptions("/path/to/MyApp.app");

// Options will include validated configuration with defaults applied
console.log(options.format); // "UDZO" (default compressed)
console.log(options.contents); // Default app + Applications link layout

enum Arch {
  x64 = "x64",
  arm64 = "arm64", 
  universal = "universal"
}

/**
 * Complete DMG configuration options interface
 * Extended from app-builder-lib DmgOptions
 */
interface DmgOptions {
  /** Background image path or null to use backgroundColor */
  background?: string | null;
  /** Background color (hex) when no background image */
  backgroundColor?: string | null;
  /** DMG icon path */
  icon?: string | null;
  /** Icon size in pixels (default: platform default) */
  iconSize?: number;
  /** Icon text size (10-16, default: 12) */
  iconTextSize?: number;
  /** Window configuration for DMG appearance */
  window?: {
    x?: number;
    y?: number; 
    width?: number;
    height?: number;
  };
  /** DMG compression format (UDZO, UDRO, UDBZ) */
  format?: string;
  /** Enable internet-enabled DMG (deprecated) */
  internetEnabled?: boolean;
  /** Code sign the DMG file */
  sign?: boolean;
  /** Custom DMG title template */
  title?: string;
  /** Write update info for auto-updater */
  writeUpdateInfo?: boolean;
  /** Contents layout configuration */
  contents?: Array<{
    /** Path to file/directory or special paths like /Applications */
    path?: string;
    /** X position in DMG window */
    x: number;
    /** Y position in DMG window */
    y: number;
    /** Display name (optional) */
    name?: string;
    /** Type of content item */
    type?: "file" | "link" | "dir";
  }>;
}

// Enable DMG signing in configuration
const dmgOptions = {
  sign: true, // Enable code signing
  // Other options...
};