Private/Logging/Write-SecretRotationLog.ps1

function Write-SecretRotationLog {
    <#
    .SYNOPSIS
        Writes a log entry to the configured logging destination (file or Windows Event Log).
    .DESCRIPTION
        Central logging entry point, called by every public cmdlet. Reads and normalizes the
        Logging section of the configuration, filters by MinimumLevel, and dispatches to
        Write-SecretRotationFileLogEntry or Write-SecretRotationEventLogEntry depending on Mode.
        Every entry is stamped with the current OS user name ([System.Environment]::UserName,
        not WindowsIdentity - this module must also run under PowerShell Core on non-Windows
        platforms for its non-ActiveDirectory backends).

        When -BoundParameters is supplied, its keys/values are appended to the message with
        Credential/Password/Secret/Token/APIKey-named parameters redacted, so secrets - most
        importantly a freshly generated account password - never reach a log file or the
        Windows Event Log. Callers typically pass this only on the Debug-level entry-point log
        for each cmdlet invocation.

        No-ops silently when logging is disabled (Logging.Enabled = $false, the default) or
        when Level is below the configured MinimumLevel. Never throws - a logging failure must
        never break the cmdlet's actual password-rotation work.
    .PARAMETER Config
        The parsed configuration object returned by Read-SecretRotationConfigFile.
    .PARAMETER Level
        Severity of this entry: Debug, Information, Warning, or Error.
    .PARAMETER Message
        The log message.
    .PARAMETER CmdletName
        Name of the calling cmdlet, e.g. $MyInvocation.MyCommand.Name.
    .PARAMETER TargetName
        Optional. The config target involved in this action.
    .PARAMETER BoundParameters
        Optional. $PSBoundParameters of the calling cmdlet; appended to the message with
        sensitive values redacted.
    .EXAMPLE
        Write-SecretRotationLog -Config $config -Level Debug -CmdletName $MyInvocation.MyCommand.Name -Message 'Cmdlet invoked' -BoundParameters $PSBoundParameters
        Logs cmdlet entry with its bound parameters (secrets redacted) at Debug level.
    .EXAMPLE
        Write-SecretRotationLog -Config $config -Level Information -CmdletName 'Update-SecretRotationAccountPassword' -TargetName 'corp-ad-svcaccount1' -Message 'Password rotated and split into 5 share(s)'
        Logs a one-line summary of a successful operation.
    #>

    [CmdletBinding()]
    param(
        [Parameter(Mandatory)]
        [PSCustomObject] $Config,

        [Parameter(Mandatory)]
        [ValidateSet('Debug', 'Information', 'Warning', 'Error')]
        [string] $Level,

        [Parameter(Mandatory)]
        [string] $Message,

        [Parameter(Mandatory)]
        [string] $CmdletName,

        [Parameter()]
        [string] $TargetName,

        [Parameter()]
        [hashtable] $BoundParameters
    )

    try {
        $loggingConfig = Get-SecretRotationLoggingConfig -Config $Config
        if (-not $loggingConfig.Enabled) { return }

        $minimumSeverity = $script:LogLevelSeverity[$loggingConfig.MinimumLevel]
        $entrySeverity   = $script:LogLevelSeverity[$Level]
        if ($entrySeverity -lt $minimumSeverity) { return }

        $fullMessage = $Message
        if ($BoundParameters) {
            $redacted = foreach ($key in ($BoundParameters.Keys | Sort-Object)) {
                if ($key -match 'Credential|Password|Secret|Token|APIKey') {
                    "$key=<redacted>"
                } else {
                    "$key=$($BoundParameters[$key])"
                }
            }
            $fullMessage = "$Message ($($redacted -join '; '))"
        }

        $entry = [PSCustomObject]@{
            Timestamp  = Get-Date
            Level      = $Level
            UserName   = [System.Environment]::UserName
            CmdletName = $CmdletName
            TargetName = $TargetName
            Message    = $fullMessage
        }

        if ($loggingConfig.Mode -eq 'EventLog') {
            Write-SecretRotationEventLogEntry -EventLog $loggingConfig.EventLog -Entry $entry
        } else {
            Write-SecretRotationFileLogEntry -File $loggingConfig.File -Entry $entry
        }
    } catch {
        if (-not $script:LoggingSinkFailed) {
            $script:LoggingSinkFailed = $true
            Write-Warning "Posh-SecretRotation logging failed and will be skipped for the rest of this session: $_"
        }
    }
}