Get Csv or excel data with php

if (isset($_POST["data"])) {

    // Get file extension
    $file_extension = pathinfo($_FILES["data"]["name"], PATHINFO_EXTENSION);
    // Validate file input to check if is not empty
    if (!file_exists($_FILES["data"]["tmp_name"])) {
        $response = array(
            "type" => "error",
            "message" => "File input should not be empty."
        );
    } // Validate file input to check if is with valid extension
    else if ($file_extension != "csv") {
        $response = array(
            "type" => "error",
            "message" => "Invalid CSV: File must have .csv extension."
        );
        echo '334343';
    } // Validate file size
    else if (($_FILES["data"]["size"] > 2000000)) {
        $response = array(
            "type" => "error",
            "message" => "Invalid CSV: File size is too large."
        );
    } // Validate if all the records have same number of fields
    else {
        $lengthArray = array();

        $row = 1;
        if (($fp = fopen($_FILES["data"]["tmp_name"], "r")) !== FALSE) {
            fgetcsv($fp, 1000, ",");
            while (($data = fgetcsv($fp, 1000, ",")) !== FALSE) {
                $lengthArray[] = count($data);
               
            }
            fclose($fp);
        }

        $lengthArray = array_unique($lengthArray);

        if (count($lengthArray) == 1) {
            $response = array(
                "type" => "success",
                "message" => "File Validation Success."
            );
        } else {
            $response = array(
                "type" => "error",
                "message" => "Invalid CSV: Count mismatch."
            );
        }
    }
}