Add headless flag for unattended execution

build/windows/finalize-install-package.sh

@@ -1,5 +1,7 @@
 #!/usr/bin/env bash
 
+set -ex
+
 ##########
 ## Read config
 ##########

docs/technical/smapi.md

@@ -32,6 +32,7 @@ argument | purpose
 `--install` | Preselects the install action, skipping the prompt asking what the user wants to do.
 `--uninstall` | Preselects the uninstall action, skipping the prompt asking what the user wants to do.
 `--game-path "path"` | Specifies the full path to the folder containing the Stardew Valley executable, skipping automatic detection and any prompt to choose a path. If the path is not valid, the installer displays an error.
+`--headless` | Installs or Uninstalls SMAPI without any user interaction. Should only be used in scripts, tools or if you know what you're doing.
 
 SMAPI itself recognises five arguments, but these are meant for internal use or testing, and might
 change without warning. **On Linux/macOS**, command-line arguments won't work; see _environment
@@ -96,7 +97,7 @@ Windows](#on-windows)_ section below to create a build that retains the icon.**
    2. Run `sudo apt update` in WSL to update the package list.
    3. The rest of the instructions below should be run in WSL.
 2. Install the required software:
-   1. Install the [.NET 5 SDK](https://docs.microsoft.com/en-us/dotnet/core/install/linux-ubuntu).  
+   1. Install the [.NET 5 SDK](https://docs.microsoft.com/en-us/dotnet/core/install/linux-ubuntu).
       _For Ubuntu-based systems, you can run `lsb_release -a` to get the Ubuntu version number._
    2. [Install Steam](https://linuxconfig.org/how-to-install-steam-on-ubuntu-20-04-focal-fossa-linux).
    3. Launch `steam` and install the game like usual.

src/SMAPI.Installer/InteractiveInstaller.cs

@@ -33,6 +33,9 @@ namespace StardewModdingApi.Installer
             "SMAPI.ErrorHandler"
         };
 
+        /// <summary>If the installer should run headless, does not ask the user for any input when true.</summary>
+        private readonly bool Headless;
+
         /// <summary>Get the absolute file or folder paths to remove when uninstalling SMAPI.</summary>
         /// <param name="installDir">The folder for Stardew Valley and SMAPI.</param>
         /// <param name="modsDir">The folder for SMAPI mods.</param>
@@ -97,10 +100,11 @@ namespace StardewModdingApi.Installer
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="bundlePath">The absolute path to the directory containing the files to copy into the game folder.</param>
-        public InteractiveInstaller(string bundlePath)
+        public InteractiveInstaller(string bundlePath, bool headless)
         {
             this.BundlePath = bundlePath;
             this.ConsoleWriter = new ColorfulConsoleWriter(EnvironmentUtility.DetectPlatform());
+            this.Headless = headless;
         }
 
         /// <summary>Run the install or uninstall script.</summary>
@@ -142,14 +146,14 @@ namespace StardewModdingApi.Installer
             if (context.IsUnix)
             {
                 this.PrintError($"This is the installer for Windows. Run the 'install on {context.Platform}.{(context.Platform == Platform.Mac ? "command" : "sh")}' file instead.");
-                Console.ReadLine();
+                this.AwaitConfirmation();
                 return;
             }
 #else
             if (context.IsWindows)
             {
                 this.PrintError($"This is the installer for Linux/macOS. Run the 'install on Windows.exe' file instead.");
-                Console.ReadLine();
+                this.AwaitConfirmation();
                 return;
             }
 #endif
@@ -163,7 +167,12 @@ namespace StardewModdingApi.Installer
             if (installArg && uninstallArg)
             {
                 this.PrintError("You can't specify both --install and --uninstall command-line flags.");
-                Console.ReadLine();
+                this.AwaitConfirmation();
+                return;
+            }
+            if (!installArg && !uninstallArg && Headless)
+            {
+                this.PrintError("Either --install or --uninstall is required when running with --headless.");
                 return;
             }
 
@@ -180,7 +189,7 @@ namespace StardewModdingApi.Installer
             ** Step 2: choose a theme (can't auto-detect on Linux/macOS)
             *********/
             MonitorColorScheme scheme = MonitorColorScheme.AutoDetect;
-            if (context.IsUnix)
+            if (context.IsUnix && !Headless)
             {
                 /****
                 ** print header
@@ -245,7 +254,7 @@ namespace StardewModdingApi.Installer
                 if (installDir == null)
                 {
                     this.PrintError("Failed finding your game path.");
-                    Console.ReadLine();
+                    this.AwaitConfirmation();
                     return;
                 }
 
@@ -262,7 +271,7 @@ namespace StardewModdingApi.Installer
             if (!File.Exists(paths.GameDllPath))
             {
                 this.PrintError("The detected game install path doesn't contain a Stardew Valley executable.");
-                Console.ReadLine();
+                this.AwaitConfirmation();
                 return;
             }
             Console.Clear();
@@ -513,7 +522,7 @@ namespace StardewModdingApi.Installer
                 );
             }
 
-            Console.ReadKey();
+            this.AwaitConfirmation();
         }
 
 
@@ -594,7 +603,7 @@ namespace StardewModdingApi.Installer
                 {
                     this.PrintError($"Oops! The installer couldn't delete {path}: [{ex.GetType().Name}] {ex.Message}.");
                     this.PrintError("Try rebooting your computer and then run the installer again. If that doesn't work, try deleting it yourself then press any key to retry.");
-                    Console.ReadKey();
+                    this.AwaitConfirmation();
                 }
             }
         }
@@ -906,5 +915,14 @@ namespace StardewModdingApi.Installer
                 _ => true
             };
         }
+
+        /// <summary>Await confirmation (pressing enter) from the User.</summary>
+        private void AwaitConfirmation()
+        {
+            if (!this.Headless)
+            {
+                Console.ReadLine();
+            }
+        }
     }
 }

src/SMAPI.Installer/Program.cs

@@ -4,6 +4,7 @@ using System.IO;
 using System.IO.Compression;
 using System.Reflection;
 using System.Threading;
+using System.Linq;
 
 namespace StardewModdingApi.Installer
 {
@@ -47,8 +48,9 @@ namespace StardewModdingApi.Installer
             // set up assembly resolution
             AppDomain.CurrentDomain.AssemblyResolve += Program.CurrentDomain_AssemblyResolve;
 
+            var headless = args.Contains("--headless");
             // launch installer
-            var installer = new InteractiveInstaller(bundleDir.FullName);
+            var installer = new InteractiveInstaller(bundleDir.FullName, headless);
 
             try
             {