# Exit this script if the current device doesn't have a built-in battery
If ( $null -eq (Get-CimInstance -ClassName Win32_Battery -ErrorAction SilentlyContinue) ) { Microsoft.Powershell.Utility\Write-Output "This endpoint does not have a battery" ; Exit }

# Define file paths
$Today = Get-LongDate
$ReportPathNoExt = "${OutputDirectory}\batteryreport_${Env:COMPUTERNAME}_${Today}"
$HtmlReportPath = $ReportPathNoExt + '.html'
$XmlReportPath = $ReportPathNoExt + '.xml'

# Delete reports if they already exist
If ( Test-Path $XmlReportPath ) { Remove-Item -Path $XmlReportPath -Force }
If ( Test-Path $HtmlReportPath ) { Remove-Item -Path $HtmlReportPath -Force }

# Generate the XML report
Write-Output "Generating XML battery report: ${XmlReportPath}"

Try {
    $XmlProcess = Start-Process "powercfg.exe" `
        -ArgumentList "/batteryreport /output ""${XmlReportPath}"" /xml" `
        -Wait `
        -PassThru `
        -ErrorAction Stop
}
Catch {
    Write-Error $_.Exception.Message
    Exit 1
}

# Make sure powercfg succeeded and actually produced the report
If ( $XmlProcess.ExitCode -ne 0 ) {
    Write-Error "powercfg failed to generate the XML battery report with exit code $($XmlProcess.ExitCode)"
    Exit 1
}

If ( !(Test-Path -LiteralPath $XmlReportPath -PathType Leaf) ) {
    Write-Error "The XML battery report was not created: ${XmlReportPath}"
    Exit 1
}

# Validate the generated XML and confirm that it contains battery records
Try {
    [xml]$GeneratedBatteryReport = Get-Content `
        -LiteralPath $XmlReportPath `
        -Raw `
        -ErrorAction Stop
}
Catch {
    Write-Error "The generated battery report is not valid XML: $($_.Exception.Message)"
    Exit 1
}

$GeneratedBatteries = @(
    $GeneratedBatteryReport.BatteryReport.Batteries.Battery
)

If ( $GeneratedBatteries.Count -eq 0 ) {
    Write-Error "The generated battery report contains no battery records"
    Exit 1
}

# Convert XML report to HTML
Write-Output "Generating HTML battery report: ${HtmlReportPath}"

Try {
    $HtmlProcess = Start-Process "powercfg.exe" `
        -ArgumentList "/batteryreport /transformxml ""${XmlReportPath}"" /output ""${HtmlReportPath}""" `
        -Wait `
        -PassThru `
        -ErrorAction Stop
}
Catch {
    Write-Error $_.Exception.Message
    Exit 1
}

If ( $HtmlProcess.ExitCode -ne 0 -or !(Test-Path -LiteralPath $HtmlReportPath -PathType Leaf) ) {
    Write-Error "Failed to create the HTML battery report"
    Exit 1
}