Skeleton CLI utility 'dpk'

.gitignore

@@ -6,3 +6,4 @@ DerivedData/
 .swiftpm/configuration/registries.json
 .swiftpm/xcode/package.xcworkspace/contents.xcworkspacedata
 .netrc
+Package.resolved

Package.swift

@@ -3,8 +3,16 @@ import PackageDescription
 
 let package = Package(
   name: "darwin-apk",
+  dependencies: [
+    .package(url: "https://github.com/apple/swift-argument-parser", from: "1.5.0"),
+  ],
   targets: [
     .executableTarget(
-            name: "darwin-apk"),
+      name: "dpk",
+      dependencies: [
+        .product(name: "ArgumentParser", package: "swift-argument-parser"),
+      ],
+      path: "Sources/dpk-cli"
+    ),
   ]
 )

Sources/dpk-cli/CommandLine.swift

@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: Apache-2.0
+
+import ArgumentParser
+
+@main
+struct DarwinApkCLI: ParsableCommand {
+  static let configuration = CommandConfiguration(
+    commandName: "dpk",
+    abstract: "Command-line interface for managing packages installed via darwin-apk.",
+    subcommands: [
+      Install.self,
+      Remove.self,
+      Update.self,
+      Upgrade.self
+    ])
+}
+
+extension DarwinApkCLI {
+  struct Install: ParsableCommand {
+    static let configuration = CommandConfiguration(
+      commandName: "add",
+      abstract: "Install package(s) to the system.",
+      aliases: [ "install", "i", "a" ])
+
+    @Argument(help: "One or more package names to install to the system.")
+    var packages: [String]
+
+    func run() throws {
+      print("installing \"\(packages.joined(separator: "\", \""))\"")
+    }
+  }
+
+  struct Remove: ParsableCommand {
+    static let configuration = CommandConfiguration(
+      commandName: "remove",
+      abstract: "Remove specified package(s) from the system.",
+      aliases: [ "uninstall", "del", "rem", "r" ])
+
+    @Argument(help: "One or more package names to uninstall from the system.")
+    var packages: [String]
+
+    func run() throws {
+      print("uninstalling \"\(packages.joined(separator: "\", \""))\"")
+    }
+  }
+
+  struct Update: ParsableCommand {
+    static let configuration = CommandConfiguration(
+      commandName: "update",
+      abstract: "Update the system package repositories.",
+      aliases: [ "u" ])
+
+    func run() throws {
+      print("updating package repositories")
+    }
+  }
+
+  struct Upgrade: ParsableCommand {
+    static let configuration = CommandConfiguration(
+      commandName: "upgrade",
+      abstract: "Upgrade installed packages.",
+      aliases: [ "U" ])
+
+    @Argument(help: "Optionally specify packages to upgrade. Otherwise upgrade all packages installed on the system.")
+    var packages: [String] = []
+
+    func run() throws {
+      if packages.isEmpty {
+        print("upgrading system")
+      } else {
+        print("upgrading invidual packages: \"\(packages.joined(separator: "\", \""))\"")
+      }
+    }
+  }
+}

Sources/main.swift

@@ -1,4 +0,0 @@
-// The Swift Programming Language
-// https://docs.swift.org/swift-book
-
-print("Hello, world!")