diff --git a/erpnext/accounts/doctype/sales_invoice/sales_invoice.js b/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
index db6ac55..6f78db2 100644
--- a/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
+++ b/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
@@ -794,7 +794,7 @@
 	},
 
 	refresh: function(frm) {
-		if (frappe.boot.active_domains.includes("Healthcare")){
+		if (frappe.boot.active_domains.includes("Healthcare")) {
 			frm.set_df_property("patient", "hidden", 0);
 			frm.set_df_property("patient_name", "hidden", 0);
 			frm.set_df_property("ref_practitioner", "hidden", 0);
@@ -807,7 +807,7 @@
 				},"Get items from");
 			}
 		}
-		else{
+		else {
 			frm.set_df_property("patient", "hidden", 1);
 			frm.set_df_property("patient_name", "hidden", 1);
 			frm.set_df_property("ref_practitioner", "hidden", 1);
diff --git a/erpnext/healthcare/doctype/patient_appointment/patient_appointment.py b/erpnext/healthcare/doctype/patient_appointment/patient_appointment.py
index a88355a..d0f5eff 100755
--- a/erpnext/healthcare/doctype/patient_appointment/patient_appointment.py
+++ b/erpnext/healthcare/doctype/patient_appointment/patient_appointment.py
@@ -71,7 +71,7 @@
 	def validate_customer_created(self):
 		if frappe.db.get_single_value('Healthcare Settings', 'automate_appointment_invoicing'):
 			if not frappe.db.get_value('Patient', self.patient, 'customer'):
-				msg = _("Please create a Customer linked to the Patient")
+				msg = _("Please set a Customer linked to the Patient")
 				msg +=  " <b><a href='#Form/Patient/{0}'>{0}</a></b>".format(self.patient)
 				frappe.throw(msg, title=_('Customer Not Found'))
 
@@ -87,7 +87,7 @@
 		# Check fee validity exists
 		validity_exists = check_validity_exists(self.practitioner, self.patient)
 		if validity_exists:
-			fee_validity = frappe.get_doc('Fee Validity', validity_exists[0][0])
+			fee_validity = frappe.get_doc('Fee Validity', validity_exists.name)
 
 			# Check if the validity is valid
 			appointment_date = getdate(self.appointment_date)
diff --git a/erpnext/healthcare/utils.py b/erpnext/healthcare/utils.py
index 3a08e33..f1f9564 100644
--- a/erpnext/healthcare/utils.py
+++ b/erpnext/healthcare/utils.py
@@ -14,161 +14,233 @@
 
 @frappe.whitelist()
 def get_healthcare_services_to_invoice(patient):
-	patient = frappe.get_doc("Patient", patient)
+	patient = frappe.get_doc('Patient', patient)
 	if patient:
-		if patient.customer:
-			item_to_invoice = []
-			patient_appointments = frappe.get_list("Patient Appointment",{'patient': patient.name, 'invoiced': False},
-			order_by="appointment_date")
-			if patient_appointments:
-				fee_validity_details = []
-				valid_days = frappe.db.get_value("Healthcare Settings", None, "valid_days")
-				max_visit = frappe.db.get_value("Healthcare Settings", None, "max_visit")
-				for patient_appointment in patient_appointments:
-					patient_appointment_obj = frappe.get_doc("Patient Appointment", patient_appointment['name'])
+		validate_customer_created(patient)
+		items_to_invoice = []
+		patient_appointments = frappe.get_list(
+			'Patient Appointment',
+			fields='*',
+			filters={'patient': patient.name, 'invoiced': False},
+			order_by='appointment_date'
+		)
+		if patient_appointments:
+			items_to_invoice = get_fee_validity(patient_appointments)
 
-					if patient_appointment_obj.procedure_template:
-						if frappe.db.get_value("Clinical Procedure Template", patient_appointment_obj.procedure_template, "is_billable") == 1:
-							item_to_invoice.append({'reference_type': 'Patient Appointment', 'reference_name': patient_appointment_obj.name, 'service': patient_appointment_obj.procedure_template})
-					else:
-						practitioner_exist_in_list = False
-						skip_invoice = False
-						if fee_validity_details:
-							for validity in fee_validity_details:
-								if validity['practitioner'] == patient_appointment_obj.practitioner:
-									practitioner_exist_in_list = True
-									if validity['valid_till'] >= patient_appointment_obj.appointment_date:
-										validity['visits'] = validity['visits']+1
-										if int(max_visit) > validity['visits']:
-											skip_invoice = True
-									if not skip_invoice:
-										validity['visits'] = 1
-										validity['valid_till'] = patient_appointment_obj.appointment_date + datetime.timedelta(days=int(valid_days))
-						if not practitioner_exist_in_list:
-							valid_till = patient_appointment_obj.appointment_date + datetime.timedelta(days=int(valid_days))
-							visits = 0
-							validity_exist = check_validity_exists(patient_appointment_obj.practitioner, patient_appointment_obj.patient)
-							if validity_exist:
-								fee_validity = frappe.get_doc("Fee Validity", validity_exist[0][0])
-								valid_till = fee_validity.valid_till
-								visits = fee_validity.visited
-							fee_validity_details.append({'practitioner': patient_appointment_obj.practitioner,
-							'valid_till': valid_till, 'visits': visits})
+		encounters = get_encounters_to_invoice(patient)
+		lab_tests = get_lab_tests_to_invoice(patient)
+		clinical_procedures = get_clinical_procedures_to_invoice(patient)
+		inpatient_services = get_inpatient_services_to_invoice(patient)
 
-						if not skip_invoice:
-							practitioner_charge = 0
-							income_account = None
-							service_item = None
-							if patient_appointment_obj.practitioner:
-								service_item, practitioner_charge = get_service_item_and_practitioner_charge(patient_appointment_obj)
-								income_account = get_income_account(patient_appointment_obj.practitioner, patient_appointment_obj.company)
-							item_to_invoice.append({'reference_type': 'Patient Appointment', 'reference_name': patient_appointment_obj.name,
-							'service': service_item, 'rate': practitioner_charge,
-							'income_account': income_account})
+		items_to_invoice = encounters + lab_tests + clinical_procedures + inpatient_services
+		return items_to_invoice
 
-			encounters = frappe.get_list("Patient Encounter", {'patient': patient.name, 'invoiced': False, 'docstatus': 1})
-			if encounters:
-				for encounter in encounters:
-					encounter_obj = frappe.get_doc("Patient Encounter", encounter['name'])
-					if not encounter_obj.appointment:
-						practitioner_charge = 0
-						income_account = None
-						service_item = None
-						if encounter_obj.practitioner:
-							service_item, practitioner_charge = get_service_item_and_practitioner_charge(encounter_obj)
-							income_account = get_income_account(encounter_obj.practitioner, encounter_obj.company)
+def validate_customer_created(patient):
+	if not frappe.db.get_value('Patient', patient.name, 'customer'):
+		msg = _("Please set a Customer linked to the Patient")
+		msg +=  " <b><a href='#Form/Patient/{0}'>{0}</a></b>".format(patient.name)
+		frappe.throw(msg, title=_('Customer Not Found'))
 
-						item_to_invoice.append({'reference_type': 'Patient Encounter', 'reference_name': encounter_obj.name,
-						'service': service_item, 'rate': practitioner_charge,
-						'income_account': income_account})
-
-			lab_tests = frappe.get_list("Lab Test", {'patient': patient.name, 'invoiced': False, 'docstatus': 1})
-			if lab_tests:
-				for lab_test in lab_tests:
-					lab_test_obj = frappe.get_doc("Lab Test", lab_test['name'])
-					if frappe.db.get_value("Lab Test Template", lab_test_obj.template, "is_billable") == 1:
-						item_to_invoice.append({'reference_type': 'Lab Test', 'reference_name': lab_test_obj.name,
-						'service': frappe.db.get_value("Lab Test Template", lab_test_obj.template, "item")})
-
-			lab_rxs = frappe.db.sql("""select lp.name from `tabPatient Encounter` et, `tabLab Prescription` lp
-			where et.patient=%s and lp.parent=et.name and lp.lab_test_created=0 and lp.invoiced=0""", (patient.name))
-			if lab_rxs:
-				for lab_rx in lab_rxs:
-					rx_obj = frappe.get_doc("Lab Prescription", lab_rx[0])
-					if rx_obj.lab_test_code and (frappe.db.get_value("Lab Test Template", rx_obj.lab_test_code, "is_billable") == 1):
-						item_to_invoice.append({'reference_type': 'Lab Prescription', 'reference_name': rx_obj.name,
-						'service': frappe.db.get_value("Lab Test Template", rx_obj.lab_test_code, "item")})
-
-			procedures = frappe.get_list("Clinical Procedure", {'patient': patient.name, 'invoiced': False})
-			if procedures:
-				for procedure in procedures:
-					procedure_obj = frappe.get_doc("Clinical Procedure", procedure['name'])
-					if not procedure_obj.appointment:
-						if procedure_obj.procedure_template and (frappe.db.get_value("Clinical Procedure Template", procedure_obj.procedure_template, "is_billable") == 1):
-							item_to_invoice.append({'reference_type': 'Clinical Procedure', 'reference_name': procedure_obj.name,
-							'service': frappe.db.get_value("Clinical Procedure Template", procedure_obj.procedure_template, "item")})
-
-			procedure_rxs = frappe.db.sql("""select pp.name from `tabPatient Encounter` et,
-			`tabProcedure Prescription` pp where et.patient=%s and pp.parent=et.name and
-			pp.procedure_created=0 and pp.invoiced=0 and pp.appointment_booked=0""", (patient.name))
-			if procedure_rxs:
-				for procedure_rx in procedure_rxs:
-					rx_obj = frappe.get_doc("Procedure Prescription", procedure_rx[0])
-					if frappe.db.get_value("Clinical Procedure Template", rx_obj.procedure, "is_billable") == 1:
-						item_to_invoice.append({'reference_type': 'Procedure Prescription', 'reference_name': rx_obj.name,
-						'service': frappe.db.get_value("Clinical Procedure Template", rx_obj.procedure, "item")})
-
-			procedures = frappe.get_list("Clinical Procedure",
-			{'patient': patient.name, 'invoice_separately_as_consumables': True, 'consumption_invoiced': False,
-			'consume_stock': True, 'status': 'Completed'})
-			if procedures:
-				service_item = get_healthcare_service_item('clinical_procedure_consumable_item')
-				if not service_item:
-					msg = _(("Please Configure {0} in ").format("Clinical Procedure Consumable Item") \
-						+ """<b><a href="#Form/Healthcare Settings">Healthcare Settings</a></b>""")
-					frappe.throw(msg)
-				for procedure in procedures:
-					procedure_obj = frappe.get_doc("Clinical Procedure", procedure['name'])
-					item_to_invoice.append({'reference_type': 'Clinical Procedure', 'reference_name': procedure_obj.name,
-					'service': service_item, 'rate': procedure_obj.consumable_total_amount, 'description': procedure_obj.consumption_details})
-
-			inpatient_services = frappe.db.sql("""select io.name, io.parent from `tabInpatient Record` ip,
-			`tabInpatient Occupancy` io where ip.patient=%s and io.parent=ip.name and
-			io.left=1 and io.invoiced=0""", (patient.name))
-			if inpatient_services:
-				for inpatient_service in inpatient_services:
-					inpatient_occupancy = frappe.get_doc("Inpatient Occupancy", inpatient_service[0])
-					service_unit_type = frappe.get_doc("Healthcare Service Unit Type", frappe.db.get_value("Healthcare Service Unit", inpatient_occupancy.service_unit, "service_unit_type"))
-					if service_unit_type and service_unit_type.is_billable == 1:
-						hours_occupied = time_diff_in_hours(inpatient_occupancy.check_out, inpatient_occupancy.check_in)
-						qty = 0.5
-						if hours_occupied > 0:
-							actual_qty = hours_occupied / service_unit_type.no_of_hours
-							floor = math.floor(actual_qty)
-							decimal_part = actual_qty - floor
-							if decimal_part > 0.5:
-								qty = rounded(floor + 1, 1)
-							elif decimal_part < 0.5 and decimal_part > 0:
-								qty = rounded(floor + 0.5, 1)
-							if qty <= 0:
-								qty = 0.5
-						item_to_invoice.append({'reference_type': 'Inpatient Occupancy', 'reference_name': inpatient_occupancy.name,
-						'service': service_unit_type.item, 'qty': qty})
-
-			return item_to_invoice
+def get_fee_validity(patient_appointments):
+	fee_validity_details = []
+	items_to_invoice = []
+	valid_days = frappe.db.get_single_value('Healthcare Settings', 'valid_days')
+	max_visit = frappe.db.get_single_value('Healthcare Settings', 'max_visit')
+	for appointment in patient_appointments:
+		if appointment.procedure_template:
+			if frappe.db.get_value('Clinical Procedure Template', appointment.procedure_template, 'is_billable'):
+				items_to_invoice.append({
+					'reference_type': 'Patient Appointment',
+					'reference_name': appointment.name,
+					'service': appointment.procedure_template
+				})
 		else:
-			frappe.throw(_("The Patient {0} do not have customer refrence to invoice").format(patient.name))
+			practitioner_exist_in_list = False
+			skip_invoice = False
+			if fee_validity_details:
+				for validity in fee_validity_details:
+					if validity['practitioner'] == appointment.practitioner:
+						practitioner_exist_in_list = True
+						if validity['valid_till'] >= appointment.appointment_date:
+							validity['visits'] = validity['visits'] + 1
+							if int(max_visit) > validity['visits']:
+								skip_invoice = True
+						if not skip_invoice:
+							validity['visits'] = 1
+							validity['valid_till'] = appointment.appointment_date + datetime.timedelta(days=int(valid_days))
+
+			if not practitioner_exist_in_list:
+				valid_till = appointment.appointment_date + datetime.timedelta(days=int(valid_days))
+				visits = 0
+				validity_exist = check_validity_exists(appointment.practitioner, appointment.patient)
+				if validity_exist:
+					fee_validity = frappe.get_doc('Fee Validity', validity_exist[0][0])
+					valid_till = fee_validity.valid_till
+					visits = fee_validity.visited
+				fee_validity_details.append({'practitioner': appointment.practitioner,
+				'valid_till': valid_till, 'visits': visits})
+
+			if not skip_invoice:
+				practitioner_charge = 0
+				income_account = None
+				service_item = None
+				if appointment.practitioner:
+					service_item, practitioner_charge = get_service_item_and_practitioner_charge(appointment)
+					income_account = get_income_account(appointment.practitioner, appointment.company)
+				items_to_invoice.append({'reference_type': 'Patient Appointment', 'reference_name': appointment.name,
+				'service': service_item, 'rate': practitioner_charge,
+				'income_account': income_account})
+
+	return items_to_invoice
+
+
+def get_encounters_to_invoice(patient):
+	encounters_to_invoice = []
+	encounters = frappe.get_list(
+		'Patient Encounter',
+		fields=['*'],
+		filters={'patient': patient.name, 'invoiced': False, 'docstatus': 1}
+	)
+	if encounters:
+		for encounter in encounters:
+			if not encounter.appointment:
+				practitioner_charge = 0
+				income_account = None
+				service_item = None
+				if encounter.practitioner:
+					service_item, practitioner_charge = get_service_item_and_practitioner_charge(encounter)
+					income_account = get_income_account(encounter.practitioner, encounter.company)
+
+				encounters_to_invoice.append({
+					'reference_type': 'Patient Encounter',
+					'reference_name': encounter.name,
+					'service': service_item,
+					'rate': practitioner_charge,
+					'income_account': income_account
+				})
+
+	return encounters_to_invoice
+
+
+def get_lab_tests_to_invoice(patient):
+	lab_tests_to_invoice = []
+	lab_tests = frappe.get_list(
+		'Lab Test',
+		fields=['name', 'template'],
+		filters={'patient': patient.name, 'invoiced': False, 'docstatus': 1}
+	)
+	for lab_test in lab_tests:
+		if frappe.db.get_value('Lab Test Template', lab_test.template, 'is_billable'):
+			lab_tests_to_invoice.append({
+				'reference_type': 'Lab Test',
+				'reference_name': lab_test.name,
+				'service': frappe.db.get_value('Lab Test Template', lab_test.template, 'item')
+			})
+
+	lab_prescriptions = frappe.db.sql('''select lp.name, lp.lab_test_code from `tabPatient Encounter` et, `tabLab Prescription` lp
+	where et.patient=%s and lp.parent=et.name and lp.lab_test_created=0 and lp.invoiced=0''', (patient.name), as_dict=1)
+
+	for prescription in lab_prescriptions:
+		if prescription.lab_test_code and frappe.db.get_value('Lab Test Template', prescription.lab_test_code, 'is_billable'):
+			lab_tests_to_invoice.append({
+				'reference_type': 'Lab Prescription',
+				'reference_name': prescription.name,
+				'service': frappe.db.get_value('Lab Test Template', prescription.lab_test_code, 'item')
+			})
+
+	return lab_tests_to_invoice
+
+
+def get_clinical_procedures_to_invoice(patient):
+	clinical_procedures_to_invoice = []
+	procedures = frappe.get_list(
+		'Clinical Procedure',
+		fields='*',
+		filters={'patient': patient.name, 'invoiced': False}
+	)
+	for procedure in procedures:
+		if not procedure.appointment:
+			if procedure.procedure_template and frappe.db.get_value('Clinical Procedure Template', procedure.procedure_template, 'is_billable'):
+				clinical_procedures_to_invoice.append({
+					'reference_type': 'Clinical Procedure',
+					'reference_name': procedure.name,
+					'service': frappe.db.get_value('Clinical Procedure Template', procedure.procedure_template, 'item')
+				})
+
+		# consumables
+		if procedure.invoice_separately_as_consumables and procedure.consume_stock \
+			and procedure.status == 'Completed' and not procedure.consumption_invoiced:
+
+			service_item = get_healthcare_service_item('clinical_procedure_consumable_item')
+			if not service_item:
+				msg = _('Please Configure Clinical Procedure Consumable Item in ')
+				msg += '''<b><a href='#Form/Healthcare Settings'>Healthcare Settings</a></b>'''
+				frappe.throw(msg, title=_('Missing Configuration'))
+
+			clinical_procedures_to_invoice.append({
+				'reference_type': 'Clinical Procedure',
+				'reference_name': procedure.name,
+				'service': service_item,
+				'rate': procedure.consumable_total_amount,
+				'description': procedure.consumption_details
+			})
+
+	procedure_prescriptions = frappe.db.sql('''select pp.name, pp.procedure from `tabPatient Encounter` et,
+	`tabProcedure Prescription` pp where et.patient=%s and pp.parent=et.name and
+	pp.procedure_created=0 and pp.invoiced=0 and pp.appointment_booked=0''', (patient.name), as_dict=1)
+
+	for prescription in procedure_prescriptions:
+		if frappe.db.get_value('Clinical Procedure Template', prescription.procedure, 'is_billable'):
+			items_to_invoice.append({
+				'reference_type': 'Procedure Prescription',
+				'reference_name': prescription.name,
+				'service': frappe.db.get_value('Clinical Procedure Template', prescription.procedure, 'item')
+			})
+
+	return clinical_procedures_to_invoice
+
+
+def get_inpatient_services_to_invoice(patient):
+	services_to_invoice = []
+	inpatient_services = frappe.db.sql('''select io.* from `tabInpatient Record` ip,
+	`tabInpatient Occupancy` io where ip.patient=%s and io.parent=ip.name and
+	io.left=1 and io.invoiced=0''', (patient.name), as_dict=1)
+
+	for inpatient_occupancy in inpatient_services:
+		service_unit_type = frappe.db.get_value('Healthcare Service Unit', inpatient_occupancy.service_unit, 'service_unit_type')
+		service_unit_type = frappe.get_doc('Healthcare Service Unit Type', service_unit_type)
+		if service_unit_type and service_unit_type.is_billable:
+			hours_occupied = time_diff_in_hours(inpatient_occupancy.check_out, inpatient_occupancy.check_in)
+			qty = 0.5
+			if hours_occupied > 0:
+				actual_qty = hours_occupied / service_unit_type.no_of_hours
+				floor = math.floor(actual_qty)
+				decimal_part = actual_qty - floor
+				if decimal_part > 0.5:
+					qty = rounded(floor + 1, 1)
+				elif decimal_part < 0.5 and decimal_part > 0:
+					qty = rounded(floor + 0.5, 1)
+				if qty <= 0:
+					qty = 0.5
+			services_to_invoice.append({
+				'reference_type': 'Inpatient Occupancy',
+				'reference_name': inpatient_occupancy.name,
+				'service': service_unit_type.item, 'qty': qty
+			})
+
+	return services_to_invoice
+
 
 def get_service_item_and_practitioner_charge(doc):
-	is_inpatient = doc_is_inpatient(doc)
+	is_inpatient = doc.inpatient_record
 	if is_inpatient:
-		service_item = get_practitioner_service_item(doc.practitioner, "inpatient_visit_charge_item")
+		service_item = get_practitioner_service_item(doc.practitioner, 'inpatient_visit_charge_item')
 		if not service_item:
-			service_item = get_healthcare_service_item("inpatient_visit_charge_item")
+			service_item = get_healthcare_service_item('inpatient_visit_charge_item')
 	else:
-		service_item = get_practitioner_service_item(doc.practitioner, "op_consulting_charge_item")
+		service_item = get_practitioner_service_item(doc.practitioner, 'op_consulting_charge_item')
 		if not service_item:
-			service_item = get_healthcare_service_item("op_consulting_charge_item")
+			service_item = get_healthcare_service_item('op_consulting_charge_item')
 	if not service_item:
 		throw_config_service_item(is_inpatient)
 
@@ -178,209 +250,227 @@
 
 	return service_item, practitioner_charge
 
-def throw_config_service_item(is_inpatient):
-	service_item_lable = "Out Patient Consulting Charge Item"
-	if is_inpatient:
-		service_item_lable = "Inpatient Visit Charge Item"
 
-	msg = _(("Please Configure {0} in ").format(service_item_lable) \
-		+ """<b><a href="#Form/Healthcare Settings">Healthcare Settings</a></b>""")
-	frappe.throw(msg)
+def throw_config_service_item(is_inpatient):
+	service_item_lable = 'Out Patient Consulting Charge Item'
+	if is_inpatient:
+		service_item_lable = 'Inpatient Visit Charge Item'
+
+	msg = _(('Please Configure {0} in ').format(service_item_lable) \
+		+ '''<b><a href='#Form/Healthcare Settings'>Healthcare Settings</a></b>''')
+	frappe.throw(msg, title=_('Missing Configuration'))
+
 
 def throw_config_practitioner_charge(is_inpatient, practitioner):
-	charge_name = "OP Consulting Charge"
+	charge_name = 'OP Consulting Charge'
 	if is_inpatient:
-		charge_name = "Inpatient Visit Charge"
+		charge_name = 'Inpatient Visit Charge'
 
-	msg = _(("Please Configure {0} for Healthcare Practitioner").format(charge_name) \
-		+ """ <b><a href="#Form/Healthcare Practitioner/{0}">{0}</a></b>""".format(practitioner))
-	frappe.throw(msg)
+	msg = _(('Please Configure {0} for Healthcare Practitioner').format(charge_name) \
+		+ ''' <b><a href='#Form/Healthcare Practitioner/{0}'>{0}</a></b>'''.format(practitioner))
+	frappe.throw(msg, title=_('Missing Configuration'))
+
 
 def get_practitioner_service_item(practitioner, service_item_field):
-	return frappe.db.get_value("Healthcare Practitioner", practitioner, service_item_field)
+	return frappe.db.get_value('Healthcare Practitioner', practitioner, service_item_field)
+
 
 def get_healthcare_service_item(service_item_field):
-	return frappe.db.get_value("Healthcare Settings", None, service_item_field)
+	return frappe.db.get_single_value('Healthcare Settings', service_item_field)
 
-def doc_is_inpatient(doc):
-	is_inpatient = False
-	if doc.inpatient_record:
-		is_inpatient = True
-	return is_inpatient
 
 def get_practitioner_charge(practitioner, is_inpatient):
 	if is_inpatient:
-		practitioner_charge = frappe.db.get_value("Healthcare Practitioner", practitioner, "inpatient_visit_charge")
+		practitioner_charge = frappe.db.get_value('Healthcare Practitioner', practitioner, 'inpatient_visit_charge')
 	else:
-		practitioner_charge = frappe.db.get_value("Healthcare Practitioner", practitioner, "op_consulting_charge")
+		practitioner_charge = frappe.db.get_value('Healthcare Practitioner', practitioner, 'op_consulting_charge')
 	if practitioner_charge:
 		return practitioner_charge
 	return False
 
+
 def manage_invoice_submit_cancel(doc, method):
 	if doc.items:
 		for item in doc.items:
-			if item.get("reference_dt") and item.get("reference_dn"):
-				if frappe.get_meta(item.reference_dt).has_field("invoiced"):
+			if item.get('reference_dt') and item.get('reference_dn'):
+				if frappe.get_meta(item.reference_dt).has_field('invoiced'):
 					set_invoiced(item, method, doc.name)
 
-	if method=="on_submit" and frappe.db.get_value("Healthcare Settings", None, "create_lab_test_on_si_submit") == '1':
-		create_multiple("Sales Invoice", doc.name)
+	if method=='on_submit' and frappe.db.get_single_value('Healthcare Settings', 'create_lab_test_on_si_submit'):
+		create_multiple('Sales Invoice', doc.name)
+
 
 def set_invoiced(item, method, ref_invoice=None):
 	invoiced = False
-	if(method=="on_submit"):
+	if method=='on_submit':
 		validate_invoiced_on_submit(item)
 		invoiced = True
 
 	if item.reference_dt == 'Clinical Procedure':
 		if get_healthcare_service_item('clinical_procedure_consumable_item') == item.item_code:
-			frappe.db.set_value(item.reference_dt, item.reference_dn, "consumption_invoiced", invoiced)
+			frappe.db.set_value(item.reference_dt, item.reference_dn, 'consumption_invoiced', invoiced)
 		else:
-			frappe.db.set_value(item.reference_dt, item.reference_dn, "invoiced", invoiced)
+			frappe.db.set_value(item.reference_dt, item.reference_dn, 'invoiced', invoiced)
 	else:
-		frappe.db.set_value(item.reference_dt, item.reference_dn, "invoiced", invoiced)
+		frappe.db.set_value(item.reference_dt, item.reference_dn, 'invoiced', invoiced)
 
 	if item.reference_dt == 'Patient Appointment':
 		if frappe.db.get_value('Patient Appointment', item.reference_dn, 'procedure_template'):
-			dt_from_appointment = "Clinical Procedure"
+			dt_from_appointment = 'Clinical Procedure'
 		else:
 			manage_fee_validity(item.reference_dn, method, ref_invoice)
-			dt_from_appointment = "Patient Encounter"
+			dt_from_appointment = 'Patient Encounter'
 		manage_doc_for_appoitnment(dt_from_appointment, item.reference_dn, invoiced)
 
 	elif item.reference_dt == 'Lab Prescription':
-		manage_prescriptions(invoiced, item.reference_dt, item.reference_dn, "Lab Test", "lab_test_created")
+		manage_prescriptions(invoiced, item.reference_dt, item.reference_dn, 'Lab Test', 'lab_test_created')
 
 	elif item.reference_dt == 'Procedure Prescription':
-		manage_prescriptions(invoiced, item.reference_dt, item.reference_dn, "Clinical Procedure", "procedure_created")
+		manage_prescriptions(invoiced, item.reference_dt, item.reference_dn, 'Clinical Procedure', 'procedure_created')
+
 
 def validate_invoiced_on_submit(item):
 	if item.reference_dt == 'Clinical Procedure' and get_healthcare_service_item('clinical_procedure_consumable_item') == item.item_code:
-			is_invoiced = frappe.db.get_value(item.reference_dt, item.reference_dn, "consumption_invoiced")
+			is_invoiced = frappe.db.get_value(item.reference_dt, item.reference_dn, 'consumption_invoiced')
 	else:
-		is_invoiced = frappe.db.get_value(item.reference_dt, item.reference_dn, "invoiced")
-	if is_invoiced == 1:
-		frappe.throw(_("The item referenced by {0} - {1} is already invoiced"\
+		is_invoiced = frappe.db.get_value(item.reference_dt, item.reference_dn, 'invoiced')
+	if is_invoiced:
+		frappe.throw(_('The item referenced by {0} - {1} is already invoiced'\
 		).format(item.reference_dt, item.reference_dn))
 
+
 def manage_prescriptions(invoiced, ref_dt, ref_dn, dt, created_check_field):
 	created = frappe.db.get_value(ref_dt, ref_dn, created_check_field)
-	if created == 1:
+	if created:
 		# Fetch the doc created for the prescription
 		doc_created = frappe.db.get_value(dt, {'prescription': ref_dn})
 		frappe.db.set_value(dt, doc_created, 'invoiced', invoiced)
 
+
 def check_validity_exists(practitioner, patient):
 	return frappe.db.exists({
-			"doctype": "Fee Validity",
-			"practitioner": practitioner,
-			"patient": patient})
+			'doctype': 'Fee Validity',
+			'practitioner': practitioner,
+			'patient': patient})
+
 
 def manage_fee_validity(appointment_name, method, ref_invoice=None):
-	appointment_doc = frappe.get_doc("Patient Appointment", appointment_name)
-	validity_exist = check_validity_exists(appointment_doc.practitioner, appointment_doc.patient)
+	appointment_doc = frappe.get_doc('Patient Appointment', appointment_name)
+	validity_exists = check_validity_exists(appointment_doc.practitioner, appointment_doc.patient)
 	do_not_update = False
 	visited = 0
 	if validity_exist:
-		fee_validity = frappe.get_doc("Fee Validity", validity_exist[0][0])
+		fee_validity = frappe.get_doc('Fee Validity', validity_exists.name)
 		# Check if the validity is valid
-		if (fee_validity.valid_till >= appointment_doc.appointment_date):
-			if (method == "on_cancel" and appointment_doc.status != "Closed"):
+		if fee_validity.valid_till >= appointment_doc.appointment_date:
+			if method == 'on_cancel' and appointment_doc.status != 'Closed':
 				if ref_invoice == fee_validity.ref_invoice:
 					visited = fee_validity.visited - 1
 					if visited < 0:
 						visited = 0
-					frappe.db.set_value("Fee Validity", fee_validity.name, "visited", visited)
+					frappe.db.set_value('Fee Validity', fee_validity.name, 'visited', visited)
 				do_not_update = True
-			elif (method == "on_submit" and fee_validity.visited < fee_validity.max_visit):
+			elif method == 'on_submit' and fee_validity.visited < fee_validity.max_visit:
 				visited = fee_validity.visited + 1
-				frappe.db.set_value("Fee Validity", fee_validity.name, "visited", visited)
+				frappe.db.set_value('Fee Validity', fee_validity.name, 'visited', visited)
 				do_not_update = True
 			else:
 				do_not_update = False
 
 		if not do_not_update:
 			fee_validity = update_fee_validity(fee_validity, appointment_doc.appointment_date, ref_invoice)
-			visited = fee_validity.visited
 	else:
 		fee_validity = create_fee_validity(appointment_doc.practitioner, appointment_doc.patient, appointment_doc.appointment_date, ref_invoice)
-		visited = fee_validity.visited
 
-	# Mark All Patient Appointment invoiced = True in the validity range do not cross the max visit
-	if (method == "on_cancel"):
+	visited = fee_validity.visited
+	mark_appointments_as_invoiced(fee_validity, ref_invoice, method)
+
+	if method == 'on_cancel':
 		invoiced = True
 	else:
 		invoiced = False
 
+	if method == 'on_cancel':
+		ref_invoice_in_fee_validity = frappe.db.get_value('Fee Validity', fee_validity.name, 'ref_invoice')
+		if ref_invoice_in_fee_validity == ref_invoice:
+			frappe.delete_doc('Fee Validity', fee_validity.name)
+
+
+def mark_appointments_as_invoiced(fee_validity, ref_invoice, method):
 	patient_appointments = appointments_valid_in_fee_validity(appointment_doc, invoiced)
 	if patient_appointments and fee_validity:
 		visit = visited
 		for appointment in patient_appointments:
-			if (method == "on_cancel" and appointment.status != "Closed"):
+			if method == 'on_cancel' and appointment.status != 'Closed':
 				if ref_invoice == fee_validity.ref_invoice:
-					visited = visited - 1
+					visited -= 1
 					if visited < 0:
 						visited = 0
-					frappe.db.set_value("Fee Validity", fee_validity.name, "visited", visited)
-				frappe.db.set_value("Patient Appointment", appointment.name, "invoiced", False)
-				manage_doc_for_appoitnment("Patient Encounter", appointment.name, False)
-			elif method == "on_submit" and int(fee_validity.max_visit) > visit:
+					frappe.db.set_value('Fee Validity', fee_validity.name, 'visited', visited)
+				frappe.db.set_value('Patient Appointment', appointment.name, 'invoiced', False)
+				manage_doc_for_appoitnment('Patient Encounter', appointment.name, False)
+			elif method == 'on_submit' and int(fee_validity.max_visit) > visit:
 				if ref_invoice == fee_validity.ref_invoice:
-					visited = visited + 1
-					frappe.db.set_value("Fee Validity", fee_validity.name, "visited", visited)
-				frappe.db.set_value("Patient Appointment", appointment.name, "invoiced", True)
-				manage_doc_for_appoitnment("Patient Encounter", appointment.name, True)
+					visited += 1
+					frappe.db.set_value('Fee Validity', fee_validity.name, 'visited', visited)
+				frappe.db.set_value('Patient Appointment', appointment.name, 'invoiced', True)
+				manage_doc_for_appoitnment('Patient Encounter', appointment.name, True)
 			if ref_invoice == fee_validity.ref_invoice:
 				visit = visit + 1
 
-	if method == "on_cancel":
-		ref_invoice_in_fee_validity = frappe.db.get_value("Fee Validity", fee_validity.name, 'ref_invoice')
-		if ref_invoice_in_fee_validity == ref_invoice:
-			frappe.delete_doc("Fee Validity", fee_validity.name)
 
 def appointments_valid_in_fee_validity(appointment, invoiced):
-	valid_days = frappe.db.get_value("Healthcare Settings", None, "valid_days")
-	max_visit = frappe.db.get_value("Healthcare Settings", None, "max_visit")
+	valid_days = frappe.db.get_single_value('Healthcare Settings', 'valid_days')
+	max_visit = frappe.db.get_single_value('Healthcare Settings', 'max_visit')
 	if int(max_visit) < 1:
 		max_visit = 1
 	valid_days_date = add_days(getdate(appointment.appointment_date), int(valid_days))
-	return frappe.get_list("Patient Appointment",{'patient': appointment.patient, 'invoiced': invoiced,
-	'appointment_date':("<=", valid_days_date), 'appointment_date':(">=", getdate(appointment.appointment_date)),
-	'practitioner': appointment.practitioner}, order_by="appointment_date", limit=int(max_visit)-1)
+
+	return frappe.get_list('Patient Appointment',{
+		'patient': appointment.patient,
+		'invoiced': invoiced,
+		'appointment_date':('<=', valid_days_date),
+		'appointment_date':('>=', getdate(appointment.appointment_date)),
+		'practitioner': appointment.practitioner
+	}, order_by='appointment_date', limit=int(max_visit)-1)
+
 
 def manage_doc_for_appoitnment(dt_from_appointment, appointment, invoiced):
 	dn_from_appointment = frappe.db.exists(
-		dt_from_appointment,
-		{
-			"appointment": appointment
-		}
+		doctype=dt_from_appointment,
+		filters={'appointment': appointment}
 	)
 	if dn_from_appointment:
-		frappe.db.set_value(dt_from_appointment, dn_from_appointment, "invoiced", invoiced)
+		frappe.db.set_value(dt_from_appointment, dn_from_appointment, 'invoiced', invoiced)
+
 
 @frappe.whitelist()
 def get_drugs_to_invoice(encounter):
-	encounter = frappe.get_doc("Patient Encounter", encounter)
+	encounter = frappe.get_doc('Patient Encounter', encounter)
 	if encounter:
-		patient = frappe.get_doc("Patient", encounter.patient)
-		if patient and patient.customer:
-				item_to_invoice = []
+		patient = frappe.get_doc('Patient', encounter.patient)
+		if patient:
+			if patient.customer:
+				items_to_invoice = []
 				for drug_line in encounter.drug_prescription:
 					if drug_line.drug_code:
 						qty = 1
-						if frappe.db.get_value("Item", drug_line.drug_code, "stock_uom") == "Nos":
+						if frappe.db.get_value('Item', drug_line.drug_code, 'stock_uom') == 'Nos':
 							qty = drug_line.get_quantity()
-						description = False
-						if drug_line.dosage:
-							description = drug_line.dosage
-						if description and drug_line.period:
-							description += " for "+drug_line.period
-						if not description:
-							description = ""
-						item_to_invoice.append({'drug_code': drug_line.drug_code, 'quantity': qty,
-						'description': description})
-				return item_to_invoice
+
+						description = ''
+						if drug_line.dosage and drug_line.period:
+							description = _('{0} for {1}').format(drug_line.dosage, drug_line.period)
+
+						items_to_invoice.append({
+							'drug_code': drug_line.drug_code,
+							'quantity': qty,
+							'description': description
+						})
+				return items_to_invoice
+			else:
+				validate_customer_created(patient)
+
 
 @frappe.whitelist()
 def get_children(doctype, parent, company, is_root=False):
@@ -392,7 +482,7 @@
 		'rgt'
 	]
 	# fields = [ 'name', 'is_group', 'lft', 'rgt' ]
-	filters = [['ifnull(`{0}`,"")'.format(parent_fieldname), '=', '' if is_root else parent]]
+	filters = [['ifnull(`{0}`,'')'.format(parent_fieldname), '=', '' if is_root else parent]]
 
 	if is_root:
 		fields += ['service_unit_type'] if doctype == 'Healthcare Service Unit' else []
@@ -406,58 +496,63 @@
 
 	if doctype == 'Healthcare Service Unit':
 		for each in hc_service_units:
-			occupancy_msg = ""
+			occupancy_msg = ''
 			if each['expandable'] == 1:
 				occupied = False
 				vacant = False
-				child_list = frappe.db.sql("""
+				child_list = frappe.db.sql('''
 					select name, occupancy_status from `tabHealthcare Service Unit`
 					where inpatient_occupancy = 1 and
-					lft > %s and rgt < %s""",
+					lft > %s and rgt < %s''',
 					(each['lft'], each['rgt']))
 				for child in child_list:
 					if not occupied:
 						occupied = 0
-					if child[1] == "Occupied":
+					if child[1] == 'Occupied':
 						occupied += 1
 					if not vacant:
 						vacant = 0
-					if child[1] == "Vacant":
+					if child[1] == 'Vacant':
 						vacant += 1
 				if vacant and occupied:
-					occupancy_total = vacant+occupied
-					occupancy_msg = str(occupied) + " Occupied out of " + str(occupancy_total)
-			each["occupied_out_of_vacant"] = occupancy_msg
+					occupancy_total = vacant + occupied
+					occupancy_msg = str(occupied) + ' Occupied out of ' + str(occupancy_total)
+			each['occupied_out_of_vacant'] = occupancy_msg
 	return hc_service_units
 
+
 @frappe.whitelist()
 def get_patient_vitals(patient, from_date=None, to_date=None):
 	if not patient: return
-	vitals = frappe.db.sql("""select * from `tabVital Signs` where \
-	docstatus=1 and patient=%s order by signs_date, signs_time""", \
-	(patient), as_dict=1)
-	if vitals and vitals[0]:
+
+	vitals = frappe.db.get_all('Vital Signs', {
+			'docstatus': 1,
+			'patient': patient
+		}, order_by='signs_date signs_time')
+
+	if len(vitals):
 		return vitals
-	else:
-		return False
+	return False
+
 
 @frappe.whitelist()
 def render_docs_as_html(docs):
 	# docs key value pair {doctype: docname}
 	docs_html = "<div class='col-md-12 col-sm-12 text-muted'>"
 	for doc in docs:
-		docs_html += render_doc_as_html(doc['doctype'], doc['docname'])['html'] + "<br/>"
+		docs_html += render_doc_as_html(doc['doctype'], doc['docname'])['html'] + '<br/>'
 		return {'html': docs_html}
 
+
 @frappe.whitelist()
 def render_doc_as_html(doctype, docname, exclude_fields = []):
 	#render document as html, three column layout will break
 	doc = frappe.get_doc(doctype, docname)
 	meta = frappe.get_meta(doctype)
 	doc_html = "<div class='col-md-12 col-sm-12'>"
-	section_html = ""
-	section_label = ""
-	html = ""
+	section_html = ''
+	section_label = ''
+	html = ''
 	sec_on = False
 	col_on = 0
 	has_data = False
@@ -476,8 +571,8 @@
 			sec_on = True
 			has_data= False
 			col_on = 0
-			section_html = ""
-			html = ""
+			section_html = ''
+			html = ''
 			if df.label:
 				section_label = df.label
 			continue
@@ -493,19 +588,19 @@
 				d-6 col-sm-6'>" + html + "</div><div class='col-md-6 col-sm-6'>"
 			elif sec_on and not col_on:
 				section_html += "<div class='col-md-6 col-sm-6'>"
-			html = ""
+			html = ''
 			col_on += 1
 			if df.label:
 				html += '<br>' + df.label
 			continue
 		#on table iterate in items and create table based on in_list_view, append to section html or doc html
-		if df.fieldtype == "Table":
+		if df.fieldtype == 'Table':
 			items = doc.get(df.fieldname)
 			if not items: continue
 			child_meta = frappe.get_meta(df.options)
 			if not has_data : has_data = True
-			table_head = ""
-			table_row = ""
+			table_head = ''
+			table_row = ''
 			create_head = True
 			for item in items:
 				table_row += '<tr>'
@@ -521,24 +616,24 @@
 				create_head = False
 				table_row += '</tr>'
 			if sec_on:
-				section_html += '<table class="table table-condensed \
-				bordered">' + table_head +  table_row + '</table>'
+				section_html += "<table class='table table-condensed \
+				bordered'>" + table_head +  table_row + '</table>'
 			else:
-				html += '<table class="table table-condensed table-bordered">' \
-				+ table_head +  table_row + '</table>'
+				html += "<table class='table table-condensed table-bordered'>" \
+				+ table_head +  table_row + "</table>"
 			continue
 		#on other field types add label and value to html
 		if not df.hidden and not df.print_hide and doc.get(df.fieldname) and df.fieldname not in exclude_fields:
-			html +=  "<br>{0} : {1}".format(df.label or df.fieldname, \
+			html +=  '<br>{0} : {1}'.format(df.label or df.fieldname, \
 			doc.get(df.fieldname))
 			if not has_data : has_data = True
 	if sec_on and col_on and has_data:
-		doc_html += section_html + html + "</div></div>"
+		doc_html += section_html + html + '</div></div>'
 	elif sec_on and not col_on and has_data:
 		doc_html += "<div class='col-md-12 col-sm-12'\
 		><div class='col-md-12 col-sm-12'>" \
-		+ section_html + html +"</div></div>"
+		+ section_html + html +'</div></div>'
 	if doc_html:
-		doc_html = "<div class='small'><div class='col-md-12 text-right'><a class='btn btn-default btn-xs' href='#Form/%s/%s'></a></div>" %(doctype, docname) + doc_html + "</div>"
+		doc_html = "<div class='small'><div class='col-md-12 text-right'><a class='btn btn-default btn-xs' href='#Form/%s/%s'></a></div>" %(doctype, docname) + doc_html + '</div>'
 
 	return {'html': doc_html}