fix: add duplicate GSTIN and PAN message checks in party and address

india_compliance/gst_india/client_scripts/party.js

@@ -62,6 +62,8 @@ function validate_gstin(doctype) {
             frm.doc.gstin = gstin;
             frm.refresh_field("gstin");
 
+            india_compliance.check_duplicate_gstin(gstin, frm.doctype, frm.docname);
+
             if (!frm.fields_dict.pan) return;
 
             // extract PAN from GSTIN
@@ -89,6 +91,8 @@ function validate_pan(doctype) {
 
             frm.doc.pan = pan;
             frm.refresh_field("pan");
+
+            india_compliance.check_duplicate_pan(pan, frm.doctype, frm.docname);
             set_party_type(frm);
         },
     });

india_compliance/gst_india/utils/__init__.py

@@ -33,6 +33,7 @@
     E_INVOICE_MASTER_CODES_URL,
     GST_ACCOUNT_FIELDS,
     GST_INVOICE_NUMBER_FORMAT,
+    GST_PARTY_TYPES,
     GSTIN_FORMATS,
     PAN_NUMBER,
     PINCODE_FORMAT,
@@ -1131,3 +1132,108 @@ def has_permission_of_page(page_name, throw=False):
         )
 
     return True
+
+
+@frappe.whitelist()
+def check_duplicate_party(field, value, party_type, party=None):
+    """
+    Check duplicates based on PAN/GSTIN for the given party type.
+    """
+    if not value:
+        return
+
+    if party_type not in GST_PARTY_TYPES:
+        return
+
+    frappe.has_permission(party_type, doc=party, throw=True)
+
+    value = value.upper().strip()
+
+    # Check for duplicates
+    if field == "pan":
+        existing_parties = _get_duplicate_pan_party(value, party_type, party)
+    elif field == "gstin":
+        existing_parties = _get_duplicate_gstin_party(value, party_type, party)
+    else:
+        return
+
+    if not existing_parties:
+        return
+
+    # Show message
+    duplicate_links = []
+    for row in existing_parties:
+        party_link = get_link_to_form(party_type, row["name"])
+        if row["via_address"]:
+            address_link = get_link_to_form("Address", row["address"])
+            link_msg = _("{0} (via Address {1})").format(party_link, address_link)
+
+        else:
+            link_msg = party_link
+
+        duplicate_links.append(f"<li>{link_msg}</li>")
+
+    msg = _("{0} {1} is already registered with the following {2}(s):").format(
+        field.capitalize(), frappe.bold(value), party_type
+    )
+    msg += f"<br><br><ul>{''.join(duplicate_links)}</ul>"
+
+    frappe.msgprint(msg=msg, indicator="orange")
+
+
+def _get_duplicate_pan_party(pan, party_type, party=None):
+    filters = {"pan": ("=", pan)}
+    if party:
+        filters["name"] = ("!=", party)
+
+    return frappe.get_all(party_type, filters=filters)
+
+
+def _get_duplicate_gstin_party(gstin, party_type, party=None):
+    party_table = frappe.qb.DocType(party_type)
+    address = frappe.qb.DocType("Address")
+    dynamic_link = frappe.qb.DocType("Dynamic Link")
+
+    party_query = (
+        frappe.qb.from_(party_table)
+        .select(
+            party_table.name,
+            frappe.qb.terms.ValueWrapper(None).as_("address_name"),
+            frappe.qb.terms.ValueWrapper(0).as_("via_address"),
+        )
+        .where(party_table.gstin == gstin)
+    )
+
+    if party:
+        party_query = party_query.where(party_table.name != party)
+
+    address_query = (
+        frappe.qb.from_(address)
+        .join(dynamic_link)
+        .on(dynamic_link.parent == address.name)
+        .select(
+            dynamic_link.link_name.as_("name"),
+            address.name.as_("address_name"),
+            frappe.qb.terms.ValueWrapper(1).as_("via_address"),
+        )
+        .where(dynamic_link.link_doctype == party_type)
+        .where(address.gstin == gstin)
+    )
+
+    if party:
+        address_query = address_query.where(dynamic_link.link_name != party)
+
+    results = (party_query + address_query).orderby("via_address").run(as_dict=True)
+
+    duplicates_dict = {}
+    for row in results:
+        if row.name in duplicates_dict:
+            continue
+
+        duplicates_dict[row.name] = {
+            "name": row.name,
+            "via_address": bool(row.via_address),
+            "address": row.address_name,
+        }
+
+    return list(duplicates_dict.values())

india_compliance/public/js/quick_entry.js

@@ -28,11 +28,11 @@ class GSTQuickEntryForm extends frappe.ui.form.QuickEntryForm {
                 fieldtype: "Section Break",
                 description: this.api_enabled
                     ? __(
-                        `When you enter a GSTIN, the permanent address linked to it is
+                          `When you enter a GSTIN, the permanent address linked to it is
                         autofilled.<br>
                         Change the {0} to autofill other addresses.`,
-                        [frappe.meta.get_label("Address", "pincode")]
-                    )
+                          [frappe.meta.get_label("Address", "pincode")]
+                      )
                     : "",
                 collapsible: 0,
             },
@@ -97,10 +97,13 @@ class GSTQuickEntryForm extends frappe.ui.form.QuickEntryForm {
                 onchange: () => {
                     const d = this.dialog;
 
+                    india_compliance.check_duplicate_gstin(d.doc._gstin, this.doctype);
+
                     if (["Customer", "Supplier"].includes(this.doctype)) {
                         d.set_value(
                             `${this.doctype.toLowerCase()}_type`,
-                            this.gstin_to_party_type_map[d.doc._gstin[5]] || "Individual"
+                            this.gstin_to_party_type_map[d.doc._gstin[5]] ||
+                                "Individual"
                         );
                     }
 
@@ -109,7 +112,10 @@ class GSTQuickEntryForm extends frappe.ui.form.QuickEntryForm {
 
                     d.set_value(
                         "gst_category",
-                        india_compliance.guess_gst_category(d.doc._gstin, d.doc.country)
+                        india_compliance.guess_gst_category(
+                            d.doc._gstin,
+                            d.doc.country,
+                        ),
                     );
                 },
             },
@@ -169,21 +175,23 @@ class PartyQuickEntryForm extends GSTQuickEntryForm {
                 collapsible: 0,
             },
             {
-				label: __("First Name"),
-				fieldname: "map_to_first_name",
-				fieldtype: "Data",
-				depends_on: "eval:doc.customer_type=='Company' || doc.supplier_type=='Company'",
-			},
-             {
+                label: __("First Name"),
+                fieldname: "map_to_first_name",
+                fieldtype: "Data",
+                depends_on:
+                    "eval:doc.customer_type=='Company' || doc.supplier_type=='Company'",
+            },
+            {
                 fieldtype: "Column Break",
             },
-			{
-				label: __("Last Name"),
-				fieldname: "map_to_last_name",
-				fieldtype: "Data",
-				depends_on: "eval:doc.customer_type=='Company' || doc.supplier_type=='Company'",
-			},
-             {
+            {
+                label: __("Last Name"),
+                fieldname: "map_to_last_name",
+                fieldtype: "Data",
+                depends_on:
+                    "eval:doc.customer_type=='Company' || doc.supplier_type=='Company'",
+            },
+            {
                 fieldname: "primary_contact_section_2",
                 fieldtype: "Section Break",
                 collapsible: 0,
@@ -343,7 +351,7 @@ class AddressQuickEntryForm extends GSTQuickEntryForm {
                 "Customer",
                 "Supplier",
                 "Company",
-                "Lead"
+                "Lead",
             ].includes(doc.doctype)
         )
             return;

india_compliance/public/js/utils.js

@@ -70,6 +70,26 @@ Object.assign(india_compliance, {
         return `${month}${year}`;
     },
 
+    check_duplicate_gstin(gstin, party_type, party = null) {
+        if (!gstin || gstin.length !== 15) return;
+        this.check_duplicate_party("gstin", gstin, party_type, party);
+    },
+
+    check_duplicate_pan(pan, party_type, party = null) {
+        if (!pan || pan.length !== 10) return;
+        this.check_duplicate_party("pan", pan, party_type, party);
+    },
+
+    check_duplicate_party(field, value, party_type, party = null) {
+        if (!party_type) return;
+        if (!frappe.boot.gst_party_types.includes(party_type)) return;
+
+        frappe.call({
+            method: "india_compliance.gst_india.utils.check_duplicate_party",
+            args: { field, value, party_type, party },
+        });
+    },
+
     get_gstin_query(party, party_type = "Company", exclude_isd = false) {
         if (!party) {
             frappe.show_alert({