#requires -version 2.0

<#
 -----------------------------------------------------------------------------
 Script: demo-wmiperf-progress.ps1
 Version: 1.0
 Author: Jeffery Hicks
    http://jdhitsolutions.com/blog
    http://twitter.com/JeffHicks
    http://www.ScriptingGeek.com
 Date: 10/26/2011
 Keywords:
 Comments:

 "Those who forget to script are doomed to repeat their work."

  ****************************************************************
  * DO NOT USE IN A PRODUCTION ENVIRONMENT UNTIL YOU HAVE TESTED *
  * THOROUGHLY IN A LAB ENVIRONMENT. USE AT YOUR OWN RISK.  IF   *
  * YOU DO NOT UNDERSTAND WHAT THIS SCRIPT DOES OR HOW IT WORKS, *
  * DO NOT USE IT OUTSIDE OF A SECURE, TEST SETTING.             *
  ****************************************************************
 -----------------------------------------------------------------------------
 #> 
 
 <#
 .Synopsis
 Demo WMI Perf Counter Graph
 .Description
 This demonstration script uses the Write-Progress cmdlet to display
 the value of a WMI Performance counter. Ideally, the counter will 
 have a value of between 1 and 100. Otherwise you might need to 
 scale the value.
 
 You must specify a WMI Performance counter. The demo sample is:
 
    Win32_PerfFormattedData_PerfDisk_LogicalDisk
 
 and a filter to limit it to a single instance. The demo filter is:
 
 Name='C:'
 
 Finally, select a property. The demo property is PercentDiskTime. 
 The demo will check every 1 second (the -Sleep parameter) up to 
 60 times (the -Maximum parameter).
 
 You can also specify the name of a CSV log file to hold the results.
 
 #>

[cmdletbinding()]

Param(
[Parameter(Position=0)]
[ValidateNotNullorEmpty()]
[string]$Class="Win32_PerfFormattedData_PerfDisk_LogicalDisk",
[Parameter(Position=1)]
[ValidateNotNullorEmpty()]
[string]$Filter="Name='C:'",
[Parameter(Position=2)]
[ValidateNotNullorEmpty()]
[string]$Property="PercentDiskTime",
[string]$Computername=$env:computername,
[int]$Sleep=1,
[int]$Maximum=60,
[string]$Log
)

Write-Verbose ("Querying {0} filter {1} on {2} every {3} second(s) {4} times." -f $class,$filter,$computername,$sleep,$maximum)

#values for Write-Progress
$activity=$class
$status="$Property -> $Filter"
$current=$computername.ToUpper()

Write-Verbose "Graphing the $Property property"

#define an array to hold the results
$results=@()
for ($i=1; $i -le $maximum; $i++) {
  Try {
    $stat=get-wmiobject -class $activity -filter $filter -computername $computername -ErrorAction Stop
    $results+=$stat
    Write-progress -Activity $activity -status $status -currentoperation $current -PercentComplete $stat.$Property
    sleep -seconds $sleep
  }
  Catch {
    Write-Warning $_.Exception.Message
    Return
  }
}

if ($Log) {
    #export results to a file
    Write-Verbose "Exporting results to $log"
    $results | export-csv -Path $log
}

Write-Progress -Activity $activity -status "Finished" -Completed
Write-Verbose "Finished"