fungsi tombol simpan dan hitung sama sama menghitung fungsi simpannya ga bisa ke controller simpan

halo, saya lagi nyoba bikin program perhitungan bahan baku. di program ini saya bermaksud setelah berhasil dihitung seluruh data pada textbox yang sudah terisi dapat tersimpan. untuk sementara saya belum buat model menyimpannya tapi coba menampilkan kehalaman lain agar dapat mengetahui data dari textbox mana saja yang dapat disimpan, ternyata data yang dapat tersimpan hanya hasil perhitungannya  pada bagian hasil hitung sedangkan data dari form perhitungan bahan bakunya tidak dapat tersimpan malah bisa ikut menghitung juga.

tampilannya seperti ini :

image.png

fungsi menghitung dan simpan saya taro di dalam satu controller, nama controllernya chitung. berikut controller chitung.

<?php

	/**
	 *
	 */
	class chitung extends CI_Controller
	{

		/**function __construct()
		{
		}*/

		public function index()
		{
			$data['paper'] = 0;
			$data['glue'] = 0;
			$data['pvc'] = 0;
			$data['ep'] = 0;

			$data['kode_po'] = "";
			$data['tgl_pesan'] = "";
			$data['nama_pt'] = "";
			$data['po'] = "";


			$this->load->view('halaman/kalkulasi',$data);
		}

		public function proseshitung()
		{
			$data['kode_po'] = $this->input->post('kode_po');
			$data['tgl_pesan'] = $this->input->post('tgl_pesan');
			$data['nama_pt'] = $this->input->post('nama_pt');
			$data['po'] = $this->input->post('po');


			$data['paper'] = $data['po']/10;
			$data['glue'] = $data['po']/2;
			$data['pvc'] = $data['po']*4;
			$data['ep'] = $data['po']*2/10;

			$this->load->view('halaman/kalkulasi',$data);

		}

		public function simpan()
		{
			$data['kode_po'] = "";
			$data['tgl_pesan'] = "";
			$data['nama_pt'] = "";
			$data['po'] = "";

			$data['kode_po'] = $this->input->post('kode_po');
			$data['tgl_pesan'] = $this->input->post('tgl_pesan');
			$data['nama_pt'] = $this->input->post('nama_pt');
			$data['po'] = $this->input->post('po');
			$data['paper'] = $this->input->post('paper');
			$data['glue'] = $this->input->post('glue');
			$data['pvc'] = $this->input->post('pvc');
			$data['ep'] = $this->input->post('po');

			$this->load->view('halaman/simpan',$data);
		}
	}

?>

berikut viewnya, nama viewnya kalkulasi

<link rel="stylesheet" type="text/css" href="<?php echo base_url('assets/bootstrap/css/bootstrap.css')?>">
<div class="container">
<form method="POST" action="<?php echo base_url('chitung/proseshitung');?>">
<div class="card">
	<div class="card-header">
		<h5>Form Hitung Kebutuhan</h5>
	</div>
	<div class="card-body">
	<div class="form-group row">
		<label class="col-6">Kode Preorder</label>
		<div class="col-6">
			<input type="text" name="kode_po" value="<?php echo $kode_po; ?>">
		</div>
	</div>

	<div class="form-group row">
		<label class="col-6">Tanggal Preorder</label>
		<div class="col-6">
			<input type="date" name="tgl_pesan" value="<?php echo $tgl_pesan; ?>">
		</div>
	</div>

	<div class="form-group row">
		<label class="col-6">Nama_Perusahaan</label>
		<div class="col-6">
			<input type="text" name="nama_pt" value="<?php echo $nama_pt; ?>">
		</div>
	</div>

	<div class="form-group row">
		<label class="col-6">Jumlah PO</label>
		<div class="col-6">
			<input type="text" name="po" value="<?php echo $po; ?>">
		</div>
	</div>

	<div class="form-group row">
		<div class="col-4">
			<?php $data = [
						'type' => 'submit',
						'name' => 'hitung',
						'value'=> 'Hitung',
						'class'=> 'btn btn-info'];
						echo form_submit($data);
			?>
		</div>
	</div>
</div>
</div>
<?php echo form_open('chitung/simpan');?>
<div class="card mt-3">
	<div class="card-header">
		<h3>Hasil Hitung</h3>
	</div>
	<div class="card-body">
		<div class="form-group row">
			<label class="offset-2 col-4">Paper</label>
			<div class="col-5">
				<input type="text" name="paper" value="<?php echo $paper ;?>">
			</div>
		</div>

		<div class="form-group row">
			<label class="offset-2 col-4">Adhesive Plastisol</label>
			<div class="col-5">
				<input type="text" name="glue" value="<?php echo $glue ;?>">
			</div>
		</div>

		<div class="form-group row">
			<label class="offset-2 col-4">Plastic PVC</label>
			<div class="col-5">
				<input type="text" name="plastic pvc" value="<?php echo $pvc ;?>">
			</div>
		</div>

		<div class="form-group row">
			<label class="offset-2 col-4">Endplate AB</label>
			<div class="col-5">
				<input type="text" name="endplate" value="<?php echo $ep ;?>">
			</div>
		</div>

		<?php
			$data = [
						'type' => 'submit',
						'name' => 'simpan',
						'value'=> 'simpan',
						'class'=> 'btn btn-success'];
						echo form_submit($data);
		?>
	</div>
</div>
</div>
</div>