[enhance] Item Alternative (#13121)

* [enhance] Item Alternative

* Added two way provision in item alternative

* Test Cases

* documentation

erpnext/public/js/utils.js

@@ -184,6 +184,142 @@ $.extend(erpnext.utils, {
 	},
 });
 
+erpnext.utils.select_alternate_items = function(opts) {
+	const frm = opts.frm;
+	const warehouse_field = opts.warehouse_field || 'warehouse';
+	const item_field = opts.item_field || 'item_code';
+
+	this.data = [];
+	const dialog = new frappe.ui.Dialog({
+		title: __("Select Alternate Item"),
+		fields: [
+			{fieldtype:'Section Break', label: __('Items')},
+			{
+				fieldname: "alternative_items", fieldtype: "Table", cannot_add_rows: true,
+				in_place_edit: true, data: this.data,
+				get_data: () => {
+					return this.data;
+				},
+				fields: [{
+					fieldtype:'Data',
+					fieldname:"docname",
+					hidden: 1
+				}, {
+					fieldtype:'Link',
+					fieldname:"item_code",
+					options: 'Item',
+					in_list_view: 1,
+					read_only: 1,
+					label: __('Item Code')
+				}, {
+					fieldtype:'Link',
+					fieldname:"alternate_item",
+					options: 'Item',
+					default: "",
+					in_list_view: 1,
+					label: __('Alternate Item'),
+					onchange: function() {
+						const item_code = this.get_value();
+						const warehouse = this.grid_row.on_grid_fields_dict.warehouse.get_value();
+						if (item_code && warehouse) {
+							frappe.call({
+								method: "erpnext.stock.utils.get_latest_stock_qty",
+								args: {
+									item_code: item_code,
+									warehouse: warehouse
+								},
+								callback: (r) => {
+									this.grid_row.on_grid_fields_dict
+										.actual_qty.set_value(r.message || 0);
+								}
+							})
+						}
+					},
+					get_query: (e) => {
+						return {
+							query: "erpnext.stock.doctype.item_alternative.item_alternative.get_alternative_items",
+							filters: {
+								item_code: e.item_code
+							}
+						};
+					}
+				}, {
+					fieldtype:'Link',
+					fieldname:"warehouse",
+					options: 'Warehouse',
+					default: "",
+					in_list_view: 1,
+					label: __('Warehouse'),
+					onchange: function() {
+						const warehouse = this.get_value();
+						const item_code = this.grid_row.on_grid_fields_dict.item_code.get_value();
+						if (item_code && warehouse) {
+							frappe.call({
+								method: "erpnext.stock.utils.get_latest_stock_qty",
+								args: {
+									item_code: item_code,
+									warehouse: warehouse
+								},
+								callback: (r) => {
+									this.grid_row.on_grid_fields_dict
+										.actual_qty.set_value(r.message || 0);
+								}
+							})
+						}
+					},
+				}, {
+					fieldtype:'Float',
+					fieldname:"actual_qty",
+					default: 0,
+					read_only: 1,
+					in_list_view: 1,
+					label: __('Available Qty')
+				}]
+			},
+		],
+		primary_action: function() {
+			const args = this.get_values()["alternative_items"];
+			const alternative_items = args.filter(d => {
+				if (d.alternate_item && d.item_code != d.alternate_item) {
+					return true;
+				}
+			});
+
+			alternative_items.forEach(d => {
+				let row = frappe.get_doc(opts.child_doctype, d.docname);
+				let qty = row.qty;
+				row[item_field] = d.alternate_item;
+
+				frm.script_manager.trigger(item_field, row.doctype, row.name)
+					.then(() => {
+						frappe.model.set_value(row.doctype, row.name, 'qty', qty);
+						frappe.model.set_value(row.doctype, row.name,
+							opts.original_item_field, d.item_code);
+					});
+			});
+
+			refresh_field(opts.child_docname);
+			this.hide();
+		},
+		primary_action_label: __('Update')
+	});
+
+	frm.doc[opts.child_docname].forEach(d => {
+		if (!opts.condition || opts.condition(d)) {
+			dialog.fields_dict.alternative_items.df.data.push({
+				"docname": d.name,
+				"item_code": d[item_field],
+				"warehouse": d[warehouse_field],
+				"actual_qty": d.actual_qty
+			});
+		}
+	})
+
+	this.data = dialog.fields_dict.alternative_items.df.data;
+	dialog.fields_dict.alternative_items.grid.refresh();
+	dialog.show();
+}
+
 erpnext.utils.map_current_doc = function(opts) {
 	if(opts.get_query_filters) {
 		opts.get_query = function() {