param([string]$Mode = "element")
$ErrorActionPreference = "Continue"
Add-Type -AssemblyName UIAutomationClient, UIAutomationTypes
Add-Type -AssemblyName System.Windows.Forms
Add-Type -MemberDefinition "[DllImport(`"user32.dll`")] public static extern short GetAsyncKeyState(int key); [DllImport(`"user32.dll`", CharSet = CharSet.Unicode)] public static extern int GetWindowTextW(IntPtr h, System.Text.StringBuilder sb, int max);" -Name PickW32 -Namespace RpaPick | Out-Null

if ($Mode -eq "windows") {
  $wins = @()
  foreach ($p in Get-Process) {
    if ($p.MainWindowHandle -ne [IntPtr]::Zero -and $p.MainWindowTitle) {
      $wins += @{ title = $p.MainWindowTitle; process = $p.ProcessName }
    }
  }
  Write-Output (ConvertTo-Json $wins -Compress -AsArray)
  exit 0
}

function Get-DeepestAtPoint([double]$px, [double]$py) {
  $point = New-Object System.Windows.Automation.Point($px, $py)
  $cur = [System.Windows.Automation.AutomationElement]::FromPoint($point)
  if (-not $cur) { return $null }
  for ($depth = 0; $depth -lt 30; $depth++) {
    $children = $cur.FindAll([System.Windows.Automation.TreeScope]::Children, [System.Windows.Automation.Condition]::TrueCondition)
    $next = $null
    $nextArea = [double]::MaxValue
    foreach ($c in $children) {
      try {
        $r = $c.Current.BoundingRectangle
        if ($r.Width -gt 0 -and $r.Height -gt 0 -and $px -ge $r.X -and $px -le ($r.X + $r.Width) -and $py -ge $r.Y -and $py -le ($r.Y + $r.Height)) {
          $area = $r.Width * $r.Height
          if ($area -lt $nextArea) { $next = $c; $nextArea = $area }
        }
      } catch {}
    }
    if (-not $next) { break }
    $cur = $next
  }
  return $cur
}

$form = New-Object System.Windows.Forms.Form
$form.FormBorderStyle = [System.Windows.Forms.FormBorderStyle]::None
$form.TopMost = $true
$form.StartPosition = [System.Windows.Forms.FormStartPosition]::Manual
$form.Location = New-Object System.Drawing.Point(20, 20)
$form.Size = New-Object System.Drawing.Size(460, 130)
$form.BackColor = [System.Drawing.Color]::FromArgb(20, 60, 120)
$label = New-Object System.Windows.Forms.Label
$label.Dock = [System.Windows.Forms.DockStyle]::Fill
$label.ForeColor = [System.Drawing.Color]::White
$label.Font = New-Object System.Drawing.Font("Microsoft YaHei", 11)
$label.Text = "移动鼠标选择元素..."
$form.Controls.Add($label)
$form.Show()

$prevDown = $false
$result = $null
while ($true) {
  $ptX = [System.Windows.Forms.Cursor]::Position.X
  $ptY = [System.Windows.Forms.Cursor]::Position.Y
  $el = Get-DeepestAtPoint $ptX $ptY
  $down = ([RpaPick.PickW32]::GetAsyncKeyState(32) -band 0x8000) -ne 0
  $esc = ([RpaPick.PickW32]::GetAsyncKeyState(27) -band 0x8000) -ne 0
  if ($esc) { break }
  if ($el) {
    $c = $el.Current
    $ctrlName = $c.ControlType.ProgrammaticName.Replace("ControlType.", "")
    $label.Text = "名称: " + $c.Name + [Environment]::NewLine + "类型: " + $ctrlName + [Environment]::NewLine + "空格=拾取  Esc=取消"
  }
  if ($down -and $el) {
    $c = $el.Current
    $rootName = ""
    $walker = [System.Windows.Automation.TreeWalker]::ControlViewWalker
    $anc = $walker.GetParent($el)
    while ($anc -and -not $anc.Equals([System.Windows.Automation.AutomationElement]::RootElement)) {
      $h = $anc.Current.NativeWindowHandle
      if ($h -ne 0) {
        $sb = New-Object System.Text.StringBuilder 512
        [RpaPick.PickW32]::GetWindowTextW([IntPtr]$h, $sb, 512) | Out-Null
        if ($sb.ToString()) { $rootName = $sb.ToString(); break }
      }
      $anc = $walker.GetParent($anc)
    }
    $ctrlName = $c.ControlType.ProgrammaticName.Replace("ControlType.", "")
    $result = @{ window = $rootName; name = $c.Name; automationId = $c.AutomationId; controlType = $ctrlName; className = $c.ClassName }
    break
  }
  $prevDown = $down
  Start-Sleep -Milliseconds 80
}
$form.Close()

if ($result) { Write-Output (ConvertTo-Json $result -Compress) } else { Write-Output (ConvertTo-Json @{ cancelled = $true } -Compress) }