feat: recursive product discount

erpnext/accounts/doctype/pricing_rule/pricing_rule.json

@@ -44,6 +44,14 @@
   "column_break_21",
   "min_amt",
   "max_amt",
+  "product_discount_scheme_section",
+  "same_item",
+  "free_item",
+  "free_qty",
+  "free_item_rate",
+  "column_break_42",
+  "free_item_uom",
+  "is_recursive",
   "section_break_23",
   "valid_from",
   "valid_upto",
@@ -62,13 +70,6 @@
   "discount_amount",
   "discount_percentage",
   "for_price_list",
-  "product_discount_scheme_section",
-  "same_item",
-  "free_item",
-  "free_qty",
-  "column_break_51",
-  "free_item_uom",
-  "free_item_rate",
   "section_break_13",
   "threshold_percentage",
   "priority",
@@ -459,10 +460,6 @@
    "fieldtype": "Float",
    "label": "Qty"
   },
-  {
-   "fieldname": "column_break_51",
-   "fieldtype": "Column Break"
-  },
   {
    "fieldname": "free_item_uom",
    "fieldtype": "Link",
@@ -553,19 +550,33 @@
    "fieldname": "promotional_scheme",
    "fieldtype": "Link",
    "label": "Promotional Scheme",
-   "options": "Promotional Scheme"
+   "no_copy": 1,
+   "options": "Promotional Scheme",
+   "print_hide": 1,
+   "read_only": 1
   },
   {
    "description": "Simple Python Expression, Example: territory != 'All Territories'",
    "fieldname": "condition",
    "fieldtype": "Code",
    "label": "Condition"
+  },
+  {
+   "fieldname": "column_break_42",
+   "fieldtype": "Column Break"
+  },
+  {
+   "default": "0",
+   "description": "Discounts to be applied in sequential ranges like buy 1 get 1, buy 2 get 2, buy 3 get 3 and so on",
+   "fieldname": "is_recursive",
+   "fieldtype": "Check",
+   "label": "Is Recursive"
   }
  ],
  "icon": "fa fa-gift",
  "idx": 1,
  "links": [],
- "modified": "2020-12-04 00:36:24.698219",
+ "modified": "2021-03-06 22:01:24.840422",
  "modified_by": "Administrator",
  "module": "Accounts",
  "name": "Pricing Rule",

erpnext/accounts/doctype/pricing_rule/pricing_rule.py

@@ -237,6 +237,7 @@ def get_pricing_rule_for_item(args, price_list_rate=0, doc=None, for_validate=Fa
 		"doctype": args.doctype,
 		"has_margin": False,
 		"name": args.name,
+		"free_item_data": [],
 		"parent": args.parent,
 		"parenttype": args.parenttype,
 		"child_docname": args.get('child_docname')

erpnext/accounts/doctype/pricing_rule/utils.py

@@ -367,7 +367,7 @@ def get_qty_and_rate_for_mixed_conditions(doc, pr_doc, args):
 
 	if items and doc.get("items"):
 		for row in doc.get('items'):
-			if row.get(apply_on) not in items: continue
+			if (row.get(apply_on) or args.get(apply_on)) not in items: continue
 
 			if pr_doc.mixed_conditions:
 				amt = args.get('qty') * args.get("price_list_rate")
@@ -479,7 +479,7 @@ def apply_pricing_rule_on_transaction(doc):
 
 				doc.calculate_taxes_and_totals()
 			elif d.price_or_product_discount == 'Product':
-				item_details = frappe._dict({'parenttype': doc.doctype})
+				item_details = frappe._dict({'parenttype': doc.doctype, 'free_item_data': []})
 				get_product_discount_rule(d, item_details, doc=doc)
 				apply_pricing_rule_for_free_items(doc, item_details.free_item_data)
 				doc.set_missing_values()
@@ -508,9 +508,15 @@ def get_product_discount_rule(pricing_rule, item_details, args=None, doc=None):
 		frappe.throw(_("Free item not set in the pricing rule {0}")
 			.format(get_link_to_form("Pricing Rule", pricing_rule.name)))
 
-	item_details.free_item_data = {
+	qty = pricing_rule.free_qty or 1
+	if pricing_rule.is_recursive:
+		transaction_qty = args.get('qty') if args else doc.total_qty
+		if transaction_qty:
+			qty = flt(transaction_qty) * qty
+
+	free_item_data_args = {
 		'item_code': free_item,
-		'qty': pricing_rule.free_qty or 1,
+		'qty': qty,
 		'rate': pricing_rule.free_item_rate or 0,
 		'price_list_rate': pricing_rule.free_item_rate or 0,
 		'is_free_item': 1
@@ -519,24 +525,26 @@ def get_product_discount_rule(pricing_rule, item_details, args=None, doc=None):
 	item_data = frappe.get_cached_value('Item', free_item, ['item_name',
 		'description', 'stock_uom'], as_dict=1)
 
-	item_details.free_item_data.update(item_data)
+	free_item_data_args.update(item_data)
-	item_details.free_item_data['uom'] = pricing_rule.free_item_uom or item_data.stock_uom
+	free_item_data_args['uom'] = pricing_rule.free_item_uom or item_data.stock_uom
-	item_details.free_item_data['conversion_factor'] = get_conversion_factor(free_item,
+	free_item_data_args['conversion_factor'] = get_conversion_factor(free_item,
-		item_details.free_item_data['uom']).get("conversion_factor", 1)
+		free_item_data_args['uom']).get("conversion_factor", 1)
 
 	if item_details.get("parenttype") == 'Purchase Order':
-		item_details.free_item_data['schedule_date'] = doc.schedule_date if doc else today()
+		free_item_data_args['schedule_date'] = doc.schedule_date if doc else today()
 
 	if item_details.get("parenttype") == 'Sales Order':
-		item_details.free_item_data['delivery_date'] = doc.delivery_date if doc else today()
+		free_item_data_args['delivery_date'] = doc.delivery_date if doc else today()
+
+	item_details.free_item_data.append(free_item_data_args)
 
 def apply_pricing_rule_for_free_items(doc, pricing_rule_args, set_missing_values=False):
-	if pricing_rule_args.get('item_code'):
+	if pricing_rule_args:
-		items = [d.item_code for d in doc.items
+		items = tuple([d.item_code for d in doc.items if d.is_free_item])
-			if d.item_code == (pricing_rule_args.get("item_code")) and d.is_free_item]
 
-		if not items:
+		for args in pricing_rule_args:
-			doc.append('items', pricing_rule_args)
+			if not items or args.get('item_code') not in items:
+				doc.append('items', args)
 
 def get_pricing_rule_items(pr_doc):
 	apply_on_data = []

erpnext/accounts/doctype/promotional_scheme/promotional_scheme.py

@@ -21,7 +21,7 @@ price_discount_fields = ['rate_or_discount', 'apply_discount_on', 'apply_discoun
 	'rate', 'discount_amount', 'discount_percentage', 'validate_applied_rule']
 
 product_discount_fields = ['free_item', 'free_qty', 'free_item_uom',
-	'free_item_rate', 'same_item']
+	'free_item_rate', 'same_item', 'is_recursive']
 
 class PromotionalScheme(Document):
 	def validate(self):

erpnext/accounts/doctype/promotional_scheme_product_discount/promotional_scheme_product_discount.json

@@ -1,10 +1,12 @@
 {
+ "actions": [],
  "creation": "2019-03-24 14:48:59.649168",
  "doctype": "DocType",
  "editable_grid": 1,
  "engine": "InnoDB",
  "field_order": [
   "disable",
+  "apply_multiple_pricing_rules",
   "column_break_2",
   "rule_description",
   "section_break_1",
@@ -25,7 +27,7 @@
   "threshold_percentage",
   "column_break_15",
   "priority",
-  "apply_multiple_pricing_rules"
+  "is_recursive"
  ],
  "fields": [
   {
@@ -152,10 +154,19 @@
    "fieldname": "apply_multiple_pricing_rules",
    "fieldtype": "Check",
    "label": "Apply Multiple Pricing Rules"
+  },
+  {
+   "default": "0",
+   "description": "Discounts to be applied in sequential ranges like buy 1 get 1, buy 2 get 2, buy 3 get 3 and so on",
+   "fieldname": "is_recursive",
+   "fieldtype": "Check",
+   "label": "Is Recursive"
   }
  ],
+ "index_web_pages_for_search": 1,
  "istable": 1,
- "modified": "2019-07-21 00:00:56.674284",
+ "links": [],
+ "modified": "2021-03-06 21:58:18.162346",
  "modified_by": "Administrator",
  "module": "Accounts",
  "name": "Promotional Scheme Product Discount",

erpnext/controllers/taxes_and_totals.py

@@ -111,7 +111,10 @@ class calculate_taxes_and_totals(object):
 					item.rate_with_margin, item.base_rate_with_margin = self.calculate_margin(item)
 					if flt(item.rate_with_margin) > 0:
 						item.rate = flt(item.rate_with_margin * (1.0 - (item.discount_percentage / 100.0)), item.precision("rate"))
-						item.discount_amount = item.rate_with_margin - item.rate
+						if not item.discount_amount:
+							item.discount_amount = item.rate_with_margin - item.rate
+						elif not item.discount_percentage:
+							item.rate -= item.discount_amount
 					elif flt(item.price_list_rate) > 0:
 						item.discount_amount = item.price_list_rate - item.rate
 				elif flt(item.price_list_rate) > 0 and not item.discount_amount:

erpnext/public/js/controllers/transaction.js

@@ -576,7 +576,7 @@ erpnext.TransactionController = erpnext.taxes_and_totals.extend({
 									var d = locals[cdt][cdn];
 									me.add_taxes_from_item_tax_template(d.item_tax_rate);
 									if (d.free_item_data) {
-										me.apply_product_discount(d.free_item_data);
+										me.apply_product_discount(d);
 									}
 								},
 								() => {
@@ -1163,7 +1163,7 @@ erpnext.TransactionController = erpnext.taxes_and_totals.extend({
 
 	calculate_stock_uom_rate: function(doc, cdt, cdn) {
 		let item = frappe.get_doc(cdt, cdn);
-		item.stock_uom_rate = flt(item.rate)/flt(item.conversion_factor);	
+		item.stock_uom_rate = flt(item.rate)/flt(item.conversion_factor);
 		refresh_field("stock_uom_rate", item.name, item.parentfield);
 	},
 	service_stop_date: function(frm, cdt, cdn) {
@@ -1504,7 +1504,7 @@ erpnext.TransactionController = erpnext.taxes_and_totals.extend({
 			}
 
 			if (d.free_item_data) {
-				me.apply_product_discount(d.free_item_data);
+				me.apply_product_discount(d);
 			}
 
 			if (d.apply_rule_on_other_items) {
@@ -1538,20 +1538,30 @@ erpnext.TransactionController = erpnext.taxes_and_totals.extend({
 		}
 	},
 
-	apply_product_discount: function(free_item_data) {
+	apply_product_discount: function(args) {
-		const items = this.frm.doc.items.filter(d => (d.item_code == free_item_data.item_code
+		const items = this.frm.doc.items.filter(d => (d.is_free_item)) || [];
-			&& d.is_free_item)) || [];
 
-		if (!items.length) {
+		const exist_items = items.map(row => row.item_code);
-			let row_to_modify = frappe.model.add_child(this.frm.doc,
-				this.frm.doc.doctype + ' Item', 'items');
 
-			for (let key in free_item_data) {
+		args.free_item_data.forEach(pr_row => {
-				row_to_modify[key] = free_item_data[key];
+			let row_to_modify = {};
+			if (!items || !in_list(exist_items, pr_row.item_code)) {
+
+				row_to_modify = frappe.model.add_child(this.frm.doc,
+					this.frm.doc.doctype + ' Item', 'items');
+
+			} else if(items) {
+				row_to_modify = items.filter(d => d.item_code === pr_row.item_code)[0];
 			}
-		} if (items && items.length && free_item_data) {
+
-			items[0].qty = free_item_data.qty
+			for (let key in pr_row) {
-		}
+				row_to_modify[key] = pr_row[key];
+			}
+		});
+
+		// free_item_data is a temporary variable
+		args.free_item_data = '';
+		refresh_field('items');
 	},
 
 	apply_price_list: function(item, reset_plc_conversion) {