Log handling and date fixes

RestoreScript.ps1

@@ -9,7 +9,7 @@ param(
     [ValidateSet("catalog", "restore", "verify")]
     [string]$Action,
 
-    [Parameter(Mandatory=$true)]
+    [Parameter(Mandatory=$false)]
     [string]$SqlInstance = "sqlfcsql\TESTINST",
 
     [Parameter(Mandatory=$false)]
@@ -66,7 +66,11 @@ function Catalog-Backups {
         $timeStr = $parts[$typeIndex + 2]
         $stripe = 0
         if ($parts.Length -gt $typeIndex + 3) {
-            $stripe = [int]$parts[$typeIndex + 3]
+            $stripeVal = 0
+            if (-not [int]::TryParse($parts[$typeIndex + 3], [ref]$stripeVal)) {
+                continue
+            }
+            $stripe = $stripeVal
         }
         $key = "$dateStr$timeStr"
 
@@ -140,9 +144,10 @@ function Restore-Database {
 
     if ($StopAtTime) {
         try {
-            $targetStopAtTime = [datetime]::Parse($StopAtTime)
+            # Parse using the current OS locale so users can enter dates in their own format.
+            $targetStopAtTime = [datetime]::Parse($StopAtTime, [System.Globalization.CultureInfo]::CurrentCulture)
         } catch {
-            Write-Error "StopAtTime '$StopAtTime' is not a valid datetime value"
+            Write-Error "StopAtTime '$StopAtTime' is not a valid datetime value (expected format for your locale: $([System.Globalization.CultureInfo]::CurrentCulture.DateTimeFormat.ShortDatePattern) HH:mm:ss)"
             return
         }
     }
@@ -207,10 +212,7 @@ function Restore-Database {
     $fullFiles = $selectedFull.Files
     $fullHeader = $selectedFull.Header
 
-    $fullBaseLsn = $fullHeader.CheckpointLSN
+    $fullBaseLsn = if ($fullHeader.CheckpointLSN) { [decimal]$fullHeader.CheckpointLSN } else { [decimal]$fullHeader.FirstLSN }
-    if (-not $fullBaseLsn) {
-        $fullBaseLsn = $fullHeader.FirstLSN
-    }
 
     # Create directories if specified
     if ($DataPath -and -not (Test-Path $DataPath)) {
@@ -277,7 +279,7 @@ function Restore-Database {
                 continue
             }
 
-            if ($diffHeader.DifferentialBaseLSN -ne $fullBaseLsn) {
+            if ([decimal]$diffHeader.DifferentialBaseLSN -ne $fullBaseLsn) {
                 continue
             }
 
@@ -309,15 +311,52 @@ function Restore-Database {
     $logStartKey = if ($selectedDiffKey) { $selectedDiffKey } else { $latestFullKey }
     $logKeys = @()
 
+    # Determine the LastLSN of the last backup that will be restored (FULL or DIFF).
+    $lastRestoredHeader = if ($selectedDiff) {
+        Get-BackupInfo -Files $selectedDiff.Files -Instance $Instance
+    } else {
+        $fullHeader
+    }
+    $lastRestoredLsn = if ($lastRestoredHeader) { [decimal]$lastRestoredHeader.LastLSN } else { $null }
+
     # Select LOG backups after the latest restored FULL/DIFF point.
     if ($dbCatalog.ContainsKey('LOG')) {
         $candidateLogKeys = @($dbCatalog['LOG'].Keys | Where-Object { $_ -gt $logStartKey } | Sort-Object)
+
+        # Validate LSN continuity: the first candidate LOG must connect to the end of the FULL/DIFF chain.
+        # If there is a gap (first LOG's FirstLSN > FULL/DIFF LastLSN), no logs can be applied.
+        if ($candidateLogKeys.Count -gt 0 -and $lastRestoredLsn) {
+            $firstLogFiles = $dbCatalog['LOG'][$candidateLogKeys[0]] | Sort-Object { $_.Stripe } | ForEach-Object { $_.File }
+            $firstLogHeader = Get-BackupInfo -Files $firstLogFiles -Instance $Instance
+            if ($firstLogHeader -and [decimal]$firstLogHeader.FirstLSN -gt $lastRestoredLsn) {
+                Write-Warning "LSN gap detected: first available LOG backup ($($candidateLogKeys[0])) starts at LSN $($firstLogHeader.FirstLSN), but the restored FULL/DIFF ends at LSN $lastRestoredLsn. No log backups can be applied."
+                $candidateLogKeys = @()
+            }
+        }
+
+        $skipLogSelection = $false
         if ($isPointInTimeRestore -and $candidateLogKeys.Count -eq 0) {
+            # Only error if the target point is beyond the last restored backup's finish time.
+            # If the target is at or before that time, no logs are required and restore can proceed.
+            $lastRestoredFinish = if ($lastRestoredHeader) {
+                try { [datetime]$lastRestoredHeader.BackupFinishDate } catch { $null }
+            } else { $null }
+            $targetIsBeyondRestored = $true
+            if ($targetStopAtTime -and $lastRestoredFinish -and $targetStopAtTime -le $lastRestoredFinish) {
+                $targetIsBeyondRestored = $false
+            }
+            if ($targetStopAtLsn -and $lastRestoredLsn -and $targetStopAtLsn -le $lastRestoredLsn) {
+                $targetIsBeyondRestored = $false
+            }
+            if ($targetIsBeyondRestored) {
                 Write-Error "Point-in-time restore requested but no LOG backups are available after the selected FULL/DIFF restore point"
                 return
             }
+            # Target is within the FULL/DIFF range; no logs needed.
+            $skipLogSelection = $true
+        }
 
-        if ($StopAtTime) {
+        if (-not $skipLogSelection -and $StopAtTime) {
             $cutoffFound = $false
             foreach ($key in $candidateLogKeys) {
                 $logFiles = $dbCatalog['LOG'][$key] | Sort-Object { $_.Stripe } | ForEach-Object { $_.File }
@@ -353,7 +392,7 @@ function Restore-Database {
                 Write-Error "StopAtTime '$StopAtTime' is not covered by available LOG backups after the selected FULL/DIFF restore point"
                 return
             }
-        } elseif ($StopAtLSN) {
+        } elseif (-not $skipLogSelection -and $StopAtLSN) {
             $cutoffFound = $false
             foreach ($key in $candidateLogKeys) {
                 $logFiles = $dbCatalog['LOG'][$key] | Sort-Object { $_.Stripe } | ForEach-Object { $_.File }
@@ -395,7 +434,7 @@ function Restore-Database {
             $logKeys = $candidateLogKeys
         }
 
-        if ($isPointInTimeRestore -and $logKeys.Count -eq 0) {
+        if (-not $skipLogSelection -and $isPointInTimeRestore -and $logKeys.Count -eq 0) {
             Write-Error "Point-in-time restore requested but no usable LOG backups were selected"
             return
         }
@@ -431,7 +470,7 @@ function Restore-Database {
         }
         if ($isPointInTimeRestore) {
             if ($StopAtTime) {
-                Write-Host "PITR Target: STOPAT '$StopAtTime'"
+                Write-Host "PITR Target: STOPAT '$($targetStopAtTime.ToString([System.Globalization.CultureInfo]::CurrentCulture))'"
             } else {
                 $previewLsn = if ($StopAtLSN -like 'lsn:*') { $StopAtLSN } else { "lsn:$StopAtLSN" }
                 Write-Host "PITR Target: STOPATMARK '$previewLsn'"
@@ -473,8 +512,11 @@ function Restore-Database {
             # Apply STOPAT/STOPATMARK only on the final LOG restore statement.
             if ($isPointInTimeRestore -and $i -eq ($logKeys.Count - 1)) {
                 if ($StopAtTime) {
-                    $escapedStopAtTime = $StopAtTime.Replace("'", "''")
+                    # Use the parsed datetime formatted as ISO 8601, not the raw input string.
-                    $logWithClause = "$logWithClause, STOPAT = '$escapedStopAtTime'"
+                    # SQL Server requires a consistent datetime format; the user's input may be
+                    # locale-specific (e.g. dd/MM/yyyy) which SQL Server does not accept.
+                    $sqlStopAt = $targetStopAtTime.ToString("yyyy-MM-dd HH:mm:ss")
+                    $logWithClause = "$logWithClause, STOPAT = '$sqlStopAt'"
                 } elseif ($StopAtLSN) {
                     $normalizedLsn = if ($StopAtLSN -like "lsn:*") { $StopAtLSN } else { "lsn:$StopAtLSN" }
                     $escapedLsn = $normalizedLsn.Replace("'", "''")
@@ -510,7 +552,7 @@ function Print-BackupSummary {
         foreach ($item in $fullItems) {
             $header = @($item.Header)[0]
             if (-not $header) { continue }
-            Write-Host "  Date: $($header.BackupFinishDate) | LSN Range: $($header.FirstLSN) - $($header.LastLSN)"
+            Write-Host "  Date: $(([datetime]$header.BackupFinishDate).ToString([System.Globalization.CultureInfo]::CurrentCulture)) | LSN Range: $($header.FirstLSN) - $($header.LastLSN)"
         }
     }
 
@@ -521,7 +563,7 @@ function Print-BackupSummary {
         foreach ($item in $diffItems) {
             $header = @($item.Header)[0]
             if (-not $header) { continue }
-            Write-Host "  Date: $($header.BackupFinishDate) | Base LSN: $($header.DifferentialBaseLSN) | LSN Range: $($header.FirstLSN) - $($header.LastLSN)"
+            Write-Host "  Date: $(([datetime]$header.BackupFinishDate).ToString([System.Globalization.CultureInfo]::CurrentCulture)) | Base LSN: $($header.DifferentialBaseLSN) | LSN Range: $($header.FirstLSN) - $($header.LastLSN)"
         }
     }
 
@@ -532,7 +574,7 @@ function Print-BackupSummary {
             $firstLog = @($logItems[0].Header)[0]
             $lastLog = @($logItems[-1].Header)[0]
             Write-Host "LOG Backups:"
-            Write-Host "  Point-in-Time Range: $($firstLog.BackupStartDate) to $($lastLog.BackupFinishDate)"
+            Write-Host "  Point-in-Time Range: $(([datetime]$firstLog.BackupStartDate).ToString([System.Globalization.CultureInfo]::CurrentCulture)) to $(([datetime]$lastLog.BackupFinishDate).ToString([System.Globalization.CultureInfo]::CurrentCulture))"
             Write-Host "  LSN Range: $($firstLog.FirstLSN) - $($lastLog.LastLSN)"
 
             # Check for gaps
@@ -590,8 +632,8 @@ function Verify-Backups {
                     $header = Get-BackupInfo -Files $files -Instance $Instance
                     if ($header) {
                         Write-Host "  Backup Details:"
-                        Write-Host "    Start Date: $($header.BackupStartDate)"
+                        Write-Host "    Start Date: $(([datetime]$header.BackupStartDate).ToString([System.Globalization.CultureInfo]::CurrentCulture))"
-                        Write-Host "    Finish Date: $($header.BackupFinishDate)"
+                        Write-Host "    Finish Date: $(([datetime]$header.BackupFinishDate).ToString([System.Globalization.CultureInfo]::CurrentCulture))"
                         Write-Host "    First LSN: $($header.FirstLSN)"
                         Write-Host "    Last LSN: $($header.LastLSN)"
                         if ($header.DatabaseBackupLSN) {