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<?php
    // Connection 
    error_reporting(0);
    $start_date = $_GET['sdate'];
    $end_date = $_GET['edate'];

$sdate = date('Y-m-01');
    $edate = date('Y-m-t');
    if($start_date!="" || $end_date!="")
    {
        $pref = " created_at between '$start_date' and '$end_date'";
        $prefs = " A.created_at between '$start_date' and '$end_date'";
        $sdispdate = $start_date;
        $edispdate = $end_date;
    }
    else
    {
        $pref = " created_at between '$sdate' and '$edate'";
        $prefs = " A.created_at between '$sdate' and '$edate'";
        $sdispdate = $sdate;
        $edispdate = $edate;
    }

$con = mysqli_connect("localhost", "stengg", "ezio@123A", "stengineers");

$filename = "leads-report-$start_date-to-$end_date.xls"; // File Name
    // Download file
    header("Content-Disposition: attachment; filename=\"$filename\"");
    header("Content-Type: application/vnd.ms-excel");
    $user_query = mysqli_query($con,"select name,email,phone,company,country,pincode,product_name,message,created_at from contact where $pref");
    // Write data to file
    $flag = false;
    while ($row = mysqli_fetch_assoc($user_query)) {
        if (!$flag) {
            // display field/column names as first row
            echo implode("\t", array_keys($row)) . "\r\n";
            $flag = true;
        }
        echo implode("\t", array_values($row)) . "\r\n";
    }
?>