ERPNext Production plan - script for removing available stock from Assembly items

In the ERPNext Production plan, companies often need to produce only items which is not in the stock already.

Example 1 -  You have a sales order for 10 QTY of  X, but 3 QTY already available in the stock. So you need to produce only 7.

Example 2 - You have a sales order for 10 QTY of Y, but all 10 QTY already available in the stock. So you need not produce anything.

Use the following client and server script to do these calculations.

1. Create a client script for production plan doctype

frappe.ui.form.on('Production Plan', {

get_items:function(frm,cdt,cdn){

 let length=frm.doc.po_items.length

   for(let i=0;i<length;i++){

  var item_code=frm.doc.po_items[i].item_code

  if(item_code){

      frappe.call({

   method:"get_stock",

   args: {

       item_code:item_code},

callback: function(r) {

       var name=frm.doc.po_items[i].name

       var p_qty=frm.doc.po_items[i].planned_qty

        var stock=Math.abs((r.message[0][0])-(p_qty))

              if(stock == 0){

           cur_frm.get_field("po_items").grid.grid_rows[i].remove();

       }

        frappe.model.set_value("Production Plan Item", name, 'planned_qty', stock);

       }

   })

}

}

},

combine_items:function(frm,cdt,cdn){

   let length=frm.doc.po_items.length

    for(let i=0;i<length;i++){

  var item_code=frm.doc.po_items[i].item_code

  if(item_code){

      frappe.call({

   method:"get_stock",

   args: {

       item_code:item_code},

   callback: function(r) {

        var name=frm.doc.po_items[i].name

        var p_qty=frm.doc.po_items[i].planned_qty

      var stock=Math.abs((r.message[0][0])-(p_qty))

       frappe.model.set_value("Production Plan Item", name, 'planned_qty', stock);

            }

    })

}

}

},

})

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Create a server script with script type as ‘API’. Give API method as ‘get_stock’.

item_codee=frappe.form_dict.item_code

stock=frappe.db.sql(f"""SELECT qty_after_transaction FROM `tabStock Ledger Entry` WHERE item_code='{item_codee}' ORDER BY modified DESC LIMIT 1;""")

frappe.response["message"]=stock