Param(
    [string]$excelFilePath,
    [string]$csvFilePath
)

$logFile = "$PSScriptRoot\conversion_debug.log"
Add-Content -Path $logFile -Value "------"
Add-Content -Path $logFile -Value "Début du script : $(Get-Date)"
Add-Content -Path $logFile -Value "Fichier Excel : $excelFilePath"
Add-Content -Path $logFile -Value "Fichier CSV cible : $csvFilePath"

try {
    $excel = New-Object -ComObject Excel.Application
    $excel.Visible = $false
    $excel.DisplayAlerts = $false

    Add-Content -Path $logFile -Value "Excel COM lancé..."

    $workbook = $excel.Workbooks.Open($excelFilePath)
    Add-Content -Path $logFile -Value "Classeur ouvert."

    $worksheet = $workbook.Sheets.Item(1)
    $usedRange = $worksheet.UsedRange
    $rowCount = $usedRange.Rows.Count
    $colCount = $usedRange.Columns.Count

    Add-Content -Path $logFile -Value "Range détecté : $rowCount lignes, $colCount colonnes"

    $csvLines = @()
    for ($row = 1; $row -le $rowCount; $row++) {
        $fields = @()
        for ($col = 1; $col -le $colCount; $col++) {
            $cell = $worksheet.Cells.Item($row, $col).Text
            $fields += $cell
        }
        $csvLines += ($fields -join ';')
        if ($row % 100 -eq 0) {
            Add-Content -Path $logFile -Value "Ligne $row traitée"
        }
    }

    $csvLines | Out-File -FilePath $csvFilePath -Encoding UTF8
    Add-Content -Path $logFile -Value "Fichier CSV généré."

    $workbook.Close($false)
    $excel.Quit()

    [System.Runtime.Interopservices.Marshal]::ReleaseComObject($worksheet) | Out-Null
    [System.Runtime.Interopservices.Marshal]::ReleaseComObject($workbook) | Out-Null
    [System.Runtime.Interopservices.Marshal]::ReleaseComObject($excel) | Out-Null
    [GC]::Collect()
    [GC]::WaitForPendingFinalizers()

    Add-Content -Path $logFile -Value "Fin du script sans erreur."
}
catch {
    Add-Content -Path $logFile -Value "ERREUR : $_"
    exit 1
}