Add scripts for changing aliae config

scripts/Common/Software/aliae/Constants.ps1

@@ -0,0 +1,15 @@
+<#
+    .SYNOPSIS
+    Gets a powershell expression which points to the global `aliae` configuration.
+#>
+function Get-GlobalConfigExpression {
+    return "`"$($IsWindows ? "`$env:ProgramData" : "/etc")/aliae/aliae.yml`"";
+}
+
+<#
+    .SYNOPSIS
+    Gets the path to the global `aliae` configuration.
+#>
+function Get-GlobalConfigPath {
+    return & ([scriptblock]::Create((Get-GlobalConfigExpression)));
+}

scripts/Common/Software/aliae/Main.ps1

@@ -3,13 +3,15 @@ param(
     [hashtable] $Arguments
 )
 
+. "$PSScriptRoot/Constants.ps1";
 . "$PSScriptRoot/../PowerShell/Profile.ps1";
 . "$PSScriptRoot/../../Scripts/Software.ps1";
 
 Start-SoftwareInstaller @PSBoundParameters `
     -Configurator {
-        $pathExpression = "`"$($IsWindows ? "`$env:ProgramData" : "/etc")/aliae/aliae.yml`"";
+        . "$PSScriptRoot/Constants.ps1";
-        $path = & ([scriptblock]::Create($pathExpression));
+        $pathExpression = Get-GlobalConfigExpression;
+        $path = Get-GlobalConfigPath;
         $null = New-Item -Force -ItemType Directory (Split-Path -Parent $path);
         Copy-Item -Force "$PSScriptRoot/aliae.yml" $path;
 

scripts/Common/Software/aliae/Manage.ps1

@@ -0,0 +1,98 @@
+$null = New-Module {
+    . "$PSScriptRoot/Constants.ps1";
+
+    <#
+        .SYNOPSIS
+        Adds an alias to an existing `aliae` configuration.
+
+        .PARAMETER Name
+        The name of the alias to add.
+
+        .PARAMETER Value
+        The script the alias should point to.
+
+        .PARAMETER User
+        The user to add the alias to.
+    #>
+    function Add-Alias {
+        param(
+            [string] $Name,
+            [string] $Value,
+            [string] $User
+        )
+
+        Edit-Config `
+            -Variables @{
+                Name = "$Name";
+                Value = "$Value";
+            } `
+            ".alias |= . + [{ name: env.Name, value: env.Value }]" `
+            -User $User;
+    }
+
+    <#
+        .SYNOPSIS
+        Adds an environment variable to an existing `aliae` configuration.
+
+        .PARAMETER Name
+        The name of the variable to add.
+
+        .PARAMETER Value
+        The value of the variable.
+    #>
+    function Add-EnvironmentVariable {
+        param(
+            [string] $Name,
+            [string] $Value,
+            [string] $User
+        )
+
+        Edit-Config `
+            -Variables @{
+                Name = "$Name";
+                Value = "$Value";
+            } `
+            ".env |= . + [{ name: env.Name, value: env.Value }]" `
+            -User $User;
+    }
+
+    <#
+        .SYNOPSIS
+        Edits the underlying `aliae` configuration.
+
+        .PARAMETER Script
+        The yq script to run over the configuration.
+
+        .PARAMETER User
+        The user to edit the configuration for.
+    #>
+    function Edit-Config {
+        param(
+            [string] $Script,
+            [hashtable] $Variables,
+            [string] $User
+        )
+
+        if ($User) {
+            $path = "$($IsWindows ? "~" : "$(sudo -u $User bash -c "realpath ~")")/.aliae.yaml";
+        } else {
+            $path = Get-GlobalConfigPath;
+        }
+
+        Start-Job {
+            $file = New-TemporaryFile;
+            $variables = $using:Variables;
+
+            foreach ($key in $variables.Keys) {
+                Set-Item "Env:\$key" $variables[$key];
+            }
+
+            sudo -u $using:User cp $using:path $file;
+            yq -yi $using:Script $file;
+            sudo -u $using:User cp $file $using:path;
+            Remove-Item $file;
+        } | Receive-Job -Wait;
+    }
+
+    Export-ModuleMember -Function Add-Alias;
+};