Get-VersionReport.ps1

# Windows/Office バージョンレポート（Windows 10/11 + Microsoft 365 Apps / Click-to-Run 想定）
# 出力例:
# Windows バージョン: Windows 11 25H2 (ビルド: 26220.7623)
# Office バージョン: 2512 (ビルド: 19530.20184)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"

function Get-WindowsVersionReport {
    $regPath = "HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion"
    $os = Get-ItemProperty -Path $regPath -ErrorAction Stop

    $displayVersion = $null
    if ($os.PSObject.Properties.Name -contains "DisplayVersion") { $displayVersion = $os.DisplayVersion }
    if (-not $displayVersion -and ($os.PSObject.Properties.Name -contains "ReleaseId")) { $displayVersion = $os.ReleaseId }
    if (-not $displayVersion) { $displayVersion = "（不明）" }

    $currentBuild = $null
    if ($os.PSObject.Properties.Name -contains "CurrentBuildNumber") { $currentBuild = $os.CurrentBuildNumber }
    elseif ($os.PSObject.Properties.Name -contains "CurrentBuild") { $currentBuild = $os.CurrentBuild }

    if (-not $currentBuild) { throw "Windows の CurrentBuild( Number) を取得できませんでした。" }

    $ubr = $null
    if ($os.PSObject.Properties.Name -contains "UBR") { $ubr = $os.UBR }

    $buildFull = if ($null -ne $ubr -and "$ubr" -ne "") { "$currentBuild.$ubr" } else { "$currentBuild" }

    # 目標出力に合わせて「Windows 10/11」を推定（ProductName は環境により紛らわしい値になることがあるため）
    $buildInt = [int]$currentBuild
    $winName = if ($buildInt -ge 22000) { "Windows 11" } else { "Windows 10" }

    return "Windows バージョン: {0} {1} (ビルド: {2})" -f $winName, $displayVersion, $buildFull
}

function Get-OfficeC2RBuildInfo {
    $candidatePaths = @(
        "HKLM:\SOFTWARE\Microsoft\Office\ClickToRun\Configuration",
        "HKLM:\SOFTWARE\WOW6432Node\Microsoft\Office\ClickToRun\Configuration"
    )

    foreach ($p in $candidatePaths) {
        if (Test-Path $p) {
            $cfg = Get-ItemProperty -Path $p -ErrorAction Stop

            $raw = $null
            if ($cfg.PSObject.Properties.Name -contains "VersionToReport") { $raw = $cfg.VersionToReport }
            if (-not $raw -and ($cfg.PSObject.Properties.Name -contains "ClientVersionToReport")) { $raw = $cfg.ClientVersionToReport }

            if ($raw) {
                # raw は例: 16.0.19530.20184
                $v = [version]$raw

                $buildShort = if ($v.Revision -ge 0) { "$($v.Build).$($v.Revision)" } else { "$($v.Build)" }

                $channel = $null
                if ($cfg.PSObject.Properties.Name -contains "UpdateChannel") { $channel = $cfg.UpdateChannel }

                return [pscustomobject]@{
                    RawVersion    = $raw
                    BuildShort    = $buildShort   # 例: 19530.20184
                    UpdateChannel = $channel
                    RegPath       = $p
                }
            }
        }
    }

    return $null
}

function Resolve-OfficeYYMMFromBuild {
    param(
        [Parameter(Mandatory=$true)][string]$BuildShort,
        [int]$TimeoutSec = 10
    )

    # Microsoft Learn の「日付別更新履歴」から Build → Version(YYMM) を逆引き
    $url = "https://learn.microsoft.com/en-us/officeupdates/update-history-microsoft365-apps-by-date"

    try {
        $resp = Invoke-WebRequest -Uri $url -TimeoutSec $TimeoutSec -UseBasicParsing
        $html = $resp.Content

        $b = [regex]::Escape($BuildShort)
        $m = [regex]::Match($html, "Version\s+(?<ver>\d{4})\s*\(Build\s+$b\)", [System.Text.RegularExpressions.RegexOptions]::IgnoreCase)

        if ($m.Success) { return $m.Groups["ver"].Value }
        return $null
    }
    catch {
        return $null
    }
}

# ---- main ----
try {
    $winLine = Get-WindowsVersionReport

    $officeInfo = Get-OfficeC2RBuildInfo
    if (-not $officeInfo) {
        $officeLine = "Office バージョン: （未検出）"
    } else {
        $yymm = Resolve-OfficeYYMMFromBuild -BuildShort $officeInfo.BuildShort
        if (-not $yymm) { $yymm = "（不明）" }
        $officeLine = "Office バージョン: {0} (ビルド: {1})" -f $yymm, $officeInfo.BuildShort
    }

    Write-Output $winLine
    Write-Output $officeLine
}
catch {
    Write-Error $_
    exit 1
}