Created a multiselect prompt

PoshPrompt/PoshPrompt.psd1

@@ -68,6 +68,7 @@
         'Invoke-Text'
         'Invoke-Confirm'
         'Invoke-Select'
+        'Invoke-MultiSelect'
         'Invoke-Spinner'
     )
 

PoshPrompt/functions/Invoke-MultiSelect.ps1

@@ -0,0 +1,19 @@
+function Invoke-MultiSelect {
+    [CmdletBinding()]
+    param(
+        [Parameter(Mandatory)][string]$Message,
+        [Parameter(Mandatory)][string[]]$Options,
+        [scriptblock]$Validate = $null
+    )
+
+    $initialState = New-PromptState
+    $initialState.HoveredIndex = 0
+    $initialState.SelectedIndices = [System.Collections.Generic.HashSet[int]]::new()
+
+    $renderFn = { param($s) Render-MultiSelectPrompt -State $s -Message $Message -Options $Options }
+    $updateFn = { param($s, $k) Update-MultiSelectStateFromKey -State $s -Key $k -Options $Options -Validate $Validate }
+
+    $finalState = Invoke-RenderLoop -InitialState $initialState -RenderFunction $renderFn -UpdateFunction $updateFn
+    if ($finalState.Status -eq [PromptStatus]::Cancelled) { throw "Operation cancelled by user" }
+    return $finalState.Value
+}

PoshPrompt/internal/functions/prompts/multiselect/Render-MultiSelectPrompt.ps1

@@ -0,0 +1,53 @@
+function Render-MultiSelectPrompt {
+    param([hashtable]$State, [string]$Message, [string[]]$Options)
+
+    $symbol = Get-Symbol -State $State
+    $symbolBar = Get-SymbolColored -Symbol "│" -State $State
+    $symbolEnd = Get-SymbolColored -Symbol "└" -State $State
+
+    $prompt = "$symbol  $Message"
+
+    $renderOptions = {
+        param($state)
+        $out = ""
+        for ($i = 0; $i -lt $Options.Count; $i++) {
+            $out += "`n$symbolBar  "
+
+            $params = @{ Style = 'Dim' }
+            $box = '◻'
+            if ($state.SelectedIndices.Contains($i)) {
+                $params = @{ Foreground = 'Green' }
+                $box = '◼'
+            }
+            elseif ($i -eq $state.HoveredIndex) {
+                $params = @{ Foreground = 'Cyan' }
+            }
+            $out += "$(Format-AnsiText $box @params) "
+
+            $params = if ($i -eq $state.HoveredIndex) { @{} } else { @{ Style = 'Dim' } }
+            $out += "$(Format-AnsiText $Options[$i] @params)"
+        }
+        return $out
+    }
+
+    switch ($State.Status) {
+        Submitted {
+            $prompt += "`n$symbolBar  $(Format-AnsiText $($State.Value -join ", ") -Style 'Dim')"
+            $prompt += "`n$symbolBar"
+        }
+        Cancelled {
+            $prompt += "`n$symbolBar"
+            $prompt += "`n$symbolEnd"
+        }
+        Error {
+            $prompt += & $renderOptions $State
+            $prompt += "`n$symbolEnd  $(Format-AnsiText $State.Feedback -Foreground 'Yellow')"
+        }
+        Default {
+            $prompt += & $renderOptions $State
+            $prompt += "`n$symbolEnd"
+        }
+    }
+
+    return $prompt
+}

PoshPrompt/internal/functions/prompts/multiselect/Update-MultiSelectStateFromKey.ps1

@@ -0,0 +1,45 @@
+function Update-MultiSelectStateFromKey {
+    param(
+        [hashtable]$State,
+        [System.ConsoleKeyInfo]$Key,
+        [string[]]$Options,
+        [scriptblock]$Validate = $null
+    )
+
+    $newState = $State.Clone()
+    if (-not $newState.ContainsKey('HoveredIndex')) { $newState.HoveredIndex = 0 }
+    if (-not $newState.ContainsKey('SelectedIndices')) { $newState.SelectedIndices = [System.Collections.Generic.HashSet[int]]::new() }
+
+    switch ($Key.Key) {
+        'UpArrow' { $newState.HoveredIndex = if ($newState.HoveredIndex -gt 0) { $newState.HoveredIndex - 1 } else { $Options.Count - 1 } }
+        'DownArrow' { $newState.HoveredIndex = if ($newState.HoveredIndex -lt ($Options.Count - 1)) { $newState.HoveredIndex + 1 } else { 0 } }
+        'Spacebar' { 
+            if ($newState.SelectedIndices.Contains($newState.HoveredIndex)) { 
+                [void]$newState.SelectedIndices.Remove($newState.HoveredIndex) 
+            }
+            else { 
+                [void]$newState.SelectedIndices.Add($newState.HoveredIndex) 
+            }
+        }
+        'Enter' { 
+            $newState.Value = $Options[$newState.SelectedIndices] 
+            if ($Validate) {
+                $err = & $Validate $newState.Value
+                if ($err) {
+                    $newState.Status = [PromptStatus]::Error
+                    $newState.Feedback = $err 
+                }
+                else { $newState.Status = [PromptStatus]::Submitted }
+            }
+            else { $newState.Status = [PromptStatus]::Submitted }
+        }
+        'Escape' { $newState.Status = [PromptStatus]::Cancelled }
+        'C' { 
+            if ($Key.Modifiers -band [ConsoleModifiers]::Control) {
+                $newState.Status = [PromptStatus]::Cancelled
+            }
+        }
+    }
+
+    return $newState
+}

readme.md

@@ -14,7 +14,7 @@ PowerShell CLI input prompt library heavily inspired by [github.com/bombshell-de
 
 **New prompts/macros:**
 
-- [ ] Multiselect prompt
+- [x] Multiselect prompt
 - [ ] Password prompt
 - [ ] Logs (simple, styled text); Variants = info, success, step, warn, error, default
 - [ ] Tasks (execute multiple tasks with spinners)