csv file upload in codeigniter with check header

Form

<form method="post" enctype="multipart/form-data" action="<?php echo base_url()."admin/amazon_fees_detail/uploadcsvamazonfeesdetail"; ?>">
    <div class="form-group">
        <label class = "col-sm-3 control-label" style="text-align: end;padding-top: 5px;">CSV File Upload</label>
        <div class="col-sm-2"  style="text-align: end;padding-top: 5px;">
            <input type="file" name="csv" id="csv" required accept=".csv">
        </div>
    </div>
    <div class="form-group">
        <div class="col-sm-1">
            <button type="submit" class="btn btn-primary" id="Submit">Submit</button><br><br>
        </div>
    </div>
</form>

Controller




public function uploadcsvamazonfeesdetail(){    if (!empty($_FILES["csv"]['name'])) {        $fileName = $_FILES["csv"]["tmp_name"];        $count=0;        $fp = fopen($fileName,'r') or die("can't open file");        $wrongUser=0;        while($csv_line = fgetcsv($fp,1024))        {            $count++;            if($count == 1)            {                if($csv_line[0]=='Date' && $csv_line[1]=='Seller ID' && $csv_line[2]=='Invoice No.' && $csv_line[3]=='Amount' && $csv_line[4]=='Shipping Charges Amazon/Ad Fee' && $csv_line[5]=='PG Fees, Listing & Other Charges' && $csv_line[6]=='Storage Fee' && $csv_line[7]=='Fixed Closing Fee' && $csv_line[8]=='GST'){                    continue;                }                else{                    $this->session->set_flashdata('message', 'Upload same format which provided in sample csv');                    redirect('admin/amazon_fees_detail', 'refresh');                }            }//keep this if condition if you want to remove the first row            for($cnt = 0;  $cnt < count($csv_line); $cnt++)            {                // Get Usesr ID                $get_mws_settings = $this->mws_settings_model->getmwssettingsbymws_sellerid($csv_line[1]);                $user_id = $get_mws_settings['user_id'];                if(!empty($user_id)) {                    $insert_csv = array();                    $insert_csv['date'] = (empty($csv_line[0]) ? 'null' : $csv_line[0]);                    $insert_csv['user_id'] = (empty($csv_line[1]) ? 'null' : $user_id);                    $insert_csv['invoice_no'] = (empty($csv_line[2]) ? '' : $csv_line[2]);                }                else{                  $wrongUser++;                  $wrongUserArray[] = $csv_line[1];                }            }            // get mws settings details by id            //$get_mws_settings_details = $this->mws_settings_model->getmwssettingsbyid($insert_csv['user_id']);           if(!empty($insert_csv)) {               // data array               $data = array(                   'date' => date('Y-m-d', strtotime($insert_csv['date'])),                   'user_id' => $insert_csv['user_id'],                   'invoice_no' => $insert_csv['invoice_no'],                                  );
               // check seller settlement               if(!empty($data['invoice_no'])){                   $get_where = array(                       'date =' => $data['date'],                       'user_id =' => $data['user_id'],                       'invoice_no =' => $data['invoice_no']                   );                   $seller_settlement = $this->seller_settlement_model->get_seller_settlement_details($get_where);                   if (empty($seller_settlement)) {                       // insert amazon_fee_calculation                       $this->seller_settlement_model->adddata($data, 'amazon_fee_calculation');                   } else {                       // update amazon_fee_calculation                       $update_where = array(                           'id' => $seller_settlement['id'],                           'user_id' => $seller_settlement['user_id'],                           'date' => $seller_settlement['date'],                           'invoice_no' => $seller_settlement['invoice_no']                       );                       $this->seller_settlement_model->update_seller_settlement_details($data, $update_where);                   }               }           }        }        fclose($fp) or die("can't close file");    }    if($wrongUser == 0){        $this->session->set_flashdata('message', 'File uploaded successfully');    }    else{        $totalUsers = array_unique($wrongUserArray);
        if(!empty($totalUsers)){            $seller = implode(", ",$totalUsers);            $this->session->set_flashdata('message', '('.$seller.') Seller IDs are wrong and not uploaded their data');        } else {            $this->session->set_flashdata('message', 'File uploaded successfully');        }
    }    redirect('admin/amazon_fees_detail', 'refresh');}






Model


public function adddata($data,$table){    $this->db->insert($table,$data);    $insert_id = $this->db->insert_id();    return  $insert_id;}


function update_seller_settlement_details($data, $update_where){    $this->db->where($update_where);    return $this->db->update('amazon_fee_calculation', $data);}