powershell peco

poco.psm1

# Load
Split-Path $MyInvocation.MyCommand.Path -Parent | Push-Location
Get-ChildItem poco_*.ps1 | %{. $_}
Pop-Location

function Select-Poco
{
  Param
  (
    [Object[]]$Property = $null,

    [string]$Query = '',

    [ValidateSet('match', 'like', 'eq')]
    [string]$Filter = 'match',

    [switch]$CaseSensitive = $false,

    [switch]$InvertFilter = $false,

    [string]$Prompt = 'Query',

    [ValidateSet('TopDown', 'BottomUp')]
    [string]$Layout = 'TopDown',

    [HashTable]$Keymaps = (New-PocoKeymaps)
  )

  $Items = $input | %{,$_}

  $config = New-Config $Items $Property $Prompt $Layout $Keymaps # immutable
  $state  = New-State $Query $Filter $CaseSensitive $InvertFilter $config # mutable

  Backup-ScrBuf
  Clear-Host

  $action = 'None'
  while ($action -ne 'Cancel' -and $action -ne 'Finish')
  {
    Write-Screen $state $config
    $key, $keystr = Get-PocoKey
    $action = Get-Action $config $keystr
    $state = Update-State $state $config $action $key
  }
  
  Restore-ScrBuf
  if ($action -eq 'Finish') {$state.Entry}

  trap
  {
    Restore-ScrBuf
    break
  }  
}

Set-Alias poco Select-Poco

Export-ModuleMember -Function "*-Poco*" -Alias "poco"

poco_init.ps1

function New-Config ($Items, $Property, $Prompt, $Layout, $Keymaps)
{
  @{
    'Input' = $Items
    'Property' = $Property
    'Prompt' = $Prompt
    'Layout' = $Layout
    'Keymaps' = $Keymaps
  }
}

function New-State ($Query, $Filter, $CaseSensitive, $InvertFilter, $Config)
{
  $state = @{
    'Query' = $Query
    'Filter' = $Filter
    'CaseSensitive' = $CaseSensitive
    'InvertFilter' = $InvertFilter
    'Acrion' = 'Identity'
    'Entry' = @()
    'PrevLength' = 0
    'Screen' = @{
      'Prompt' = ''
      'FilterType' = ''
      'QueryX' = 0
      'X' = 0
      # 'Y' = 1 # 選択機能があれば...
    }
  }
  
  $state.Screen.Prompt = Get-Prompt $state $config
  $state.Screen.FilterType = Get-FilterType $state 
  $state.Screen.QueryX = $Query.Length
  $state.Screen.X = $state.Screen.Prompt.Length

  $state.Entry = Get-Entry $state $config
  
  $state  
}

poco_key.ps1

function New-PocoKeymaps
{
  @{
     'Escape' = 'Cancel'
     'Control+C' = 'Cancel'
     'Enter' = 'Finish'
     'Alt+B' = 'BackwardChar'
     'Alt+F' = 'ForwardChar'
     'Alt+A' = 'BeginningOfLine'
     'Alt+E' = 'EndOfLine'
     'Alt+D8' = 'DeleteBackwardChar'
     'Backspace' = 'DeleteBackwardChar'
     'Alt+D' = 'DeleteForwardChar'
     'Delete' = 'DeleteForwardChar'
     'Alt+U' = 'KillBeginningOfLine'
     'Alt+K' = 'KillEndOfLine'
     'Alt+R' = 'RotateMatcher'
     'Alt+C' = 'ToggleCaseSensitive'
     'Alt+I' = 'ToggleInvertFilter'

     'Alt+W' = 'DeleteBackwardWord'
     'Alt+N' = 'SelectUp'
     'Alt+P' = 'SelectDown'
     'Control+Spacebar' = 'ToggleSelectionAndSelectNext'
     'UpArrow' = 'SelectUp'
     'DownArrow' = 'SelectDown'
     'RightArrow' = 'ScrollPageUp'
     'LeftArrow' = 'ScrollPageDown'
     'Tab' = 'TabExpansion'
  }
}

function Get-PocoKey
{
  $flag = [console]::TreatControlCAsInput
  [console]::TreatControlCAsInput = $true

  $Key = [console]::ReadKey($true)

  [console]::TreatControlCAsInput = $flag

  $KeyString = $Key.Key.ToString()
  if ($Key.Modifiers -ne 0)
  {
    $m = $Key.Modifiers.ToString() -replace ', ', '+'
    $KeyString = "${m}+${KeyString}"
  }

  return $Key, $KeyString
}

function Get-Action ($config, $keystr)
{
  if ($config.Keymaps.Contains($keystr))
  {
    return $config.Keymaps[$keystr]
  }

  if ($keystr -notmatch 'Alt|Control')
  {
    'AddChar'
  }
}

poco_query.ps1

function Where-Query
{
  Param
  (
    $state,

    [Parameter(ValueFromPipeline=$True)]
    $obj
  )

  begin {$hash = Convert-QueryHash $state}

  process
  {
    if ($hash.Contains(''))
    {
      foreach ($value in $hash[''])
      {
        $test = Test-Matching $state.Screen.FilterType $obj $value
        if ($test -eq $false) {return}
      }
    }
    
    foreach ($property in $hash.Keys)
    {
      if ($property -eq '') {continue}
    
      $l = ($obj | Get-Member $property).length
      if ($l -eq 0) {continue}
      
      foreach ($value in $hash[$property])
      {
        $test = Test-Matching $state.Screen.FilterType $obj.$property $value
        if ($test -eq $false) {return}
      }
    }
    
    ,$obj
  }
}

function Convert-QueryHash ($state)
{
  $property = ''
  $hash = @{$property = @()}

  $state.Query -split ' ' | ?{$_ -ne ''} | %{
    $token = $_
    
    if ($token.StartsWith(':'))
    {
      $property = $token.Remove(0, 1)
      if (-not $hash.Contains($property))
      {
        $hash[$property] = @()
      }
    }
    else
    {
      $hash[$property] += $token
    }
  }

  $hash
}

function Test-Matching
{
  Param
  (
    [string] $FilterType,
    [string] $p,    
    [string] $value
  )

  try
  {
    switch ($FilterType)
    {
      'match'     {$p -match $value}
      'like'      {$p -like  $value}
      'eq'        {$p -eq    $value}

      'notmatch'  {$p -notmatch $value}
      'notlike'   {$p -notlike  $value}
      'neq'       {$p -ne       $value}

      'cmatch'    {$p -cmatch $value}
      'clike'     {$p -clike  $value}
      'ceq'       {$p -ceq    $value}

      'cnotmatch' {$p -cnotmatch $value}
      'cnotlike'  {$p -cnotlike  $value}
      'cneq'      {$p -cne       $value}
    }
  }
  catch
  {
    $true
  }
}

poco_scrbuf.ps1

# http://d.hatena.ne.jp/newpops/20080514
# スクリーンバッファのバックアップ
function Backup-ScrBuf
{
    $rui = Get-RawUI

    $rect = New-Object System.Management.Automation.Host.Rectangle
    $rect.Left   = 0
    $rect.Top    = 0
    $rect.Right  = $rui.WindowSize.Width
    $rect.Bottom = $rui.CursorPosition.Y
    $script:screen = $rui.GetBufferContents($rect)
}

# http://d.hatena.ne.jp/newpops/20080515
# スクリーンバッファのリストア
function Restore-ScrBuf
{
    Clear-Host
    $rui = Get-RawUI
   
    if (-not (Test-Path 'variable:screen')) {return}
   
    $origin = New-Object System.Management.Automation.Host.Coordinates(0, 0)
    $rui.SetBufferContents($origin, $script:screen)
    $pos = New-Object System.Management.Automation.Host.Coordinates(0, $script:screen.GetUpperBound(0))
    $rui.CursorPosition = $pos
}

poco_screen.ps1

function Write-Screen ($state, $config)
{
  switch ($config.Layout)
  {
    'TopDown'  {Write-TopDown  $state $config}
    'BottomUp' {Write-BottomUp $state $config}
  }
}

function Write-TopDown ($state, $config)
{
    Write-ScreenLine 0 $state.Screen.Prompt
    Write-RightInfo 0 $state
    
    if ($state.Entry.length -ne $state.PrevLength)
    {
      $h = (Get-RawUI).WindowSize.Height
      $entries = $state.Entry | Format-Table | Out-String -Stream | Select-Object -First ($h - 1)
      if ($entries -is [string]) {$entries = ,@($entries)}
      foreach ($i in 0..($h - 2))
      {
        $line = if ($i -lt $entries.length) {$entries[$i]} else {''}
        Write-ScreenLine ($i + 1) $line
      }

      $state.PrevLength = $state.Entry.length
    }

    $x = Convert-CursorPositionX $state
    Set-CursorPosition $x 0
}

function Write-BottomUp ($state, $config, $entries)
{
  if ($state.Entry.length -ne $state.PrevLength)
  {
    if ($state.Screen.Page -gt $m) {$state.Screen.Page = $m}

    $h = (Get-RawUI).WindowSize.Height
    $entries = $state.Entry | Format-Table | Out-String -Stream | Select-Object -First ($h - 1)
    if ($entries -is [string]) {$entries = ,@($entries)}
    foreach ($i in 0..($h - 2))
    {
      $line = if ($i -lt $entries.length) {$entries[$i]} else {''}
      Write-ScreenLine $i $line
    }
    
    $state.PrevLength = $state.Entry.length
  }

  Write-ScreenLine ($h - 1) $state.Screen.Prompt
  Write-RightInfo ($h - 1) $state

  $x = Convert-CursorPositionX $state
  $y = (Get-RawUI).CursorPosition.Y
  Set-CursorPosition $x $y
}

function Write-ScreenLine ($i, $line)
{
  $w = (Get-RawUI).BufferSize.Width
  Set-CursorPosition 0 $i
  ([string]$line).PadRight($w) | Write-Host -NoNewline
}

function Write-RightInfo ($i, $state)
{
  $f = $state.Screen.FilterType
  $n = $state.Entry.Length

  $h = (Get-RawUI).WindowSize.Height
  
  $info = "${f} [${n}]"
  $w = (Get-RawUI).WindowSize.Width
  Set-CursorPosition ($w - $info.length) $i
  $info | Write-Host -NoNewline

}

function Convert-CursorPositionX ($state)
{
  $str = $state.Screen.Prompt.Substring(0, $state.Screen.X)
  (Get-RawUI).LengthInBufferCells($str)
}

function Set-CursorPosition ($x, $y)
{
  $pos = New-Object System.Management.Automation.Host.Coordinates($x, $y)
  (Get-RawUI).CursorPosition = $pos
}

poco_update_state.ps1

function Update-State ($state, $config, $action, $key)
{
  switch ($action)
  {
    'AddChar'             {Add-Char $state $config $key.KeyChar}
    'ForwardChar'         {Move-ForwardChar $state}
    'BackwardChar'        {Move-BackwardChar $state}
    'BeginningOfLine'     {Move-BeginningOfLine $state}
    'EndOfLine'           {Move-EndOfLine $state}
    'DeleteBackwardChar'  {Remove-BackwardChar $state}
    'DeleteForwardChar'   {Remove-ForwardChar $state}
    'KillBeginningOfLine' {Remove-HeadLine $state}
    'KillEndOfLine'       {Remove-TailLine $state}
    'RotateMatcher'       {Select-Matcher $state}
    'ToggleCaseSensitive' {Switch-CaseSensitive $state}
    'ToggleInvertFilter'  {Switch-InvertFilter $state}
    
    default {} # None, Cancel, Finish = identity
  }
  
  $state
}

function Add-Char ($state, $config, $char)
{
  $x = $state.Screen.QueryX
  $q = $state.Query

  $state.Query = $q.Insert($x, $char)
  $state.Screen.QueryX++
  $state.Screen.X++

  $state.Screen.Prompt = Get-Prompt $state $config
  $state.Entry = Get-Entry $state $config
}

function Move-BackwardChar ($state)
{
  $x = $state.Screen.QueryX
  if ($x - 1 -ge 0)
  {
    $state.Screen.QueryX--
    $state.Screen.X--
  }
}

function Move-ForwardChar ($state)
{
  $x = $state.Screen.X
  $l = $state.Screen.Prompt.length

  if ($x + 1 -le $l)
  {
    $state.Screen.QueryX++
    $state.Screen.X++
  }
}

function Move-BeginningOfLine ($state)
{
  $state.Screen.X -= $state.Screen.QueryX
  $state.Screen.QueryX = 0
}

function Move-EndOfLine ($state)
{
  $state.Screen.QueryX = $state.Query.length
  $state.Screen.X = $state.Screen.Prompt.length
}

function Remove-BackwardChar ($state)
{
  $x = $state.Screen.QueryX
  $q = $state.Query
  
  if ($x - 1 -ge 0) {
    $state.Query = $q.Remove($x - 1, 1)
    $state.Screen.QueryX--
    $state.Screen.X--

    $state.Screen.Prompt = Get-Prompt $state $config
    $state.Entry = Get-Entry $state $config
  }
}

function Remove-ForwardChar ($state)
{
  $x = $state.Screen.X
  $l = $state.Screen.Prompt.length

  $qx = $state.Screen.QueryX
  $q = $state.Query

  if ($x + 1 -le $l)
  {
    $state.Query = $q.Remove($qx, 1)
    $state.Screen.Prompt = Get-Prompt $state $config
    $state.Entry = Get-Entry $state $config
  }
}

function Remove-HeadLine ($state)
{
  while ($state.Screen.QueryX -gt 0)
  {
    Remove-BackwardChar ($state)
  }
}

function Remove-TailLine ($state)
{
  while ($state.Screen.QueryX -lt $state.Query.length)
  {
    Remove-ForwardChar ($state)
  }
}

function Select-Matcher ($state)
{
  $arr = @('match', 'like', 'eq')

  $n = $arr.length
  $i = $arr.IndexOf($state.Filter) + 1

  $state.Filter = $arr[$i % $n]

  $state.Screen.FilterType = Get-FilterType $state
  $state.Entry = Get-Entry $state $config
}

function Switch-CaseSensitive ($state)
{
  $state.CaseSensitive = -not $state.CaseSensitive
  $state.Screen.FilterType = Get-FilterType $state
  $state.Entry = Get-Entry $state $config
}

function Switch-InvertFilter ($state)
{
  $state.InvertFilter = -not $state.InvertFilter
  $state.Screen.FilterType = Get-FilterType $state
  $state.Entry = Get-Entry $state $config
}

poco_util.ps1

function Get-RawUI {(Get-Host).UI.RawUI}

function Get-Prompt ($state, $config)
{
  $config.Prompt + '> ' + $state.Query
}

function Get-FilterType ($state)
{
  $type = ''
  if ($state.CaseSensitive) {$type += 'c'}
  if ($state.InvertFilter) {$type += 'not'}
  $type += $state.Filter
  
  $type -replace 'noteq', 'neq'
}

function Get-Entry ($state, $config)
{
  $config.Input |
    Select-Object -Property $config.Property |
    Where-Query $state
}

Hi Yamura. Thank-you for sharing this code. Could you give me a bit of guidance on how to run this code locally please? I am new to powershell module development but not new to programming in general. I am really impressed with the way I can interactively filter in powershell with this module, so I was hoping to understand more and possibly extend in some other scenarios like command history search.

Hi Yamura. Thank-you for sharing this code. Could you give me a bit of guidance on how to run this code locally please? I am new to powershell module development but not new to programming in general. I am really impressed with the way I can interactively filter in powershell with this module, so I was hoping to understand more and possibly extend in some other scenarios like command history search.

You have clone this repository:
git clone https://gist.github.com/yumura/8df37c22ae1b7942dec7
cd 8df37c22ae1b7942dec7

with Admin privileges
create folder Poco at modules for PowerShell
mkdir $PSHome/Modules/Poco
cd $PSHome/Modules/Poco

copy all content to modules folder:
copy * $PSHome/Modules/Poco