Add-Type -Path "$($PSScriptRoot)\EPPlus.dll"

function Import-Excel {
    param(
        [Parameter(ValueFromPipelineByPropertyName)]
        $FullName,
        $Sheet=1,
        [string[]]$Header
    )

    Process {

        $FullName = (Resolve-Path $FullName).Path
        write-debug "target excel file $($FullName)"

        $xl = New-Object OfficeOpenXml.ExcelPackage $FullName

        $workbook  = $xl.Workbook

        $worksheet=$workbook.Worksheets[$Sheet]
        $dimension=$worksheet.Dimension

        $Rows=$dimension.Rows
        $Columns=$dimension.Columns

        if(!$Header) {
            $Header = foreach ($Column in 1..$Columns) {
                $worksheet.Cells[1,$Column].Text
            }
        }

        foreach ($Row in 2..$Rows) {
            $h=[Ordered]@{}
            foreach ($Column in 0..($Columns-1)) {
                $Name    = $Header[$Column]
                $h.$Name = $worksheet.Cells[$Row,($Column+1)].Text
            }
            [PSCustomObject]$h
        }

        $xl.Dispose()
        $xl = $null
    }
}