# Initialize Excel sheet

$path = Read-Host -Prompt "Enter path to save file (e.g. C:\path\to\file)"
$IIS_PATH = "C:\Program Files\www\iisnode"

# Create new Excel object
$excel = New-Object -ComObject Excel.application 
$excel.SheetsInNewWorkbook = 1

# Create new Workbook
$workbook = $excel.Workbooks.Add()

# Create worksheet in workbook and make it active
$worksheet = $workbook.Sheets.Item(1)
$worksheet.Activate()

# Loop through files in directory
Get-ChildItem $IIS_NODE_PATH -Filter *.txt |Sort-Object LastWriteTime -Descending | ForEach-Object {
    
    $listOfFiles = New-Object System.Collections.ArrayList

    # Filter out error logs
    if ($_.FullName.Contains("std")){

        # Add list of files
        [void] $listOfFiles.Add($_.FullName)

        # Regex for parsing data
        $r = [regex] "\[([^\[]*)\]"
        $dateIndex = 0
        $verbosityIndex = 2
        $moduleIndex = 3
        $descriptionIndex = 4

        # Create worksheet column headers
        $worksheet.Cells.Item(1,1) = "Date"
        $worksheet.Cells.Item(1,2) = "Verbosity"
        $worksheet.Cells.Item(1,3) = "Module"
        $worksheet.Cells.Item(1,4) = "Description"


        $row = 2
        # Iterate over each file and read its contents
        foreach ($file in $listOfFiles){
            
            Write-Output "Reading file: $file"
            
            Get-Content $file | Where-Object {$_ -match $r} | ForEach-Object {
                $column = 1
                $line = $_
                
                $match = $r.matches($line)

                try{
                    $date = [DateTime]$match[$dateIndex].groups[1].value
                    $verbosity = $match[$verbosityIndex].groups[1].value
                    $module = $match[$moduleIndex].groups[1].value
                    $description = $match[$descriptionIndex].groups[1].value

                    $worksheet.Cells.Item($row,$column) = $date
                    $column++

                    $worksheet.Cells.Item($row,$column) = $verbosity
                    $column++

                    $worksheet.Cells.Item($row,$column) = $module
                    $column++
            
                    $worksheet.Cells.Item($row,$column) = $description
                    $row++
                }
                catch{
                }
            }

        }
    }
}

# Check if entered path exists. Create if not
if (!(Test-Path $path)){
    Write-Host "$path doesn't exist. Creating..."
    New-Item -ItemType Directory -Force -Path $path
}

# Save Excel file
$workbook.SaveAs($path + "\IISNodeLogs.xlsx")

# Exit and activate GC
$excel.Quit()
$excel = $Null
[gc]::Collect()
[gc]::WaitForPendingFinalizers()