fix: show pan status

(cherry picked from commit 6d777b1)

india_compliance/gst_india/client_scripts/party.js

@@ -123,10 +123,14 @@ function set_gstin_options_and_status(doctype) {
         refresh(frm) {
             set_gstin_options(frm);
             india_compliance.set_gstin_status(frm.get_field("gstin"));
+            india_compliance.set_pan_status(frm.get_field("pan"));
         },
         gstin(frm) {
             india_compliance.set_gstin_status(frm.get_field("gstin"));
         },
+        pan(frm) {
+            india_compliance.set_pan_status(frm.get_field("pan"));
+        },
     });
 }
 

india_compliance/gst_india/overrides/party.py

@@ -1,4 +1,7 @@
 import json
+import random
+
+import requests
 
 import frappe
 from frappe import _
@@ -164,3 +167,70 @@ def make_address(doc):
             "is_shipping_address": doc.get("is_shipping_address"),
         }
     ).insert()
+
+
+multiplication_table = [
+    [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
+    [1, 2, 3, 4, 0, 6, 7, 8, 9, 5],
+    [2, 3, 4, 0, 1, 7, 8, 9, 5, 6],
+    [3, 4, 0, 1, 2, 8, 9, 5, 6, 7],
+    [4, 0, 1, 2, 3, 9, 5, 6, 7, 8],
+    [5, 9, 8, 7, 6, 0, 4, 3, 2, 1],
+    [6, 5, 9, 8, 7, 1, 0, 4, 3, 2],
+    [7, 6, 5, 9, 8, 2, 1, 0, 4, 3],
+    [8, 7, 6, 5, 9, 3, 2, 1, 0, 4],
+    [9, 8, 7, 6, 5, 4, 3, 2, 1, 0],
+]
+
+permutation_table = [
+    [0, 1, 2, 3, 4, 5, 6, 7, 8, 9],
+    [1, 5, 7, 6, 2, 8, 3, 0, 9, 4],
+    [5, 8, 0, 3, 7, 9, 6, 1, 4, 2],
+    [8, 9, 1, 6, 0, 4, 3, 5, 2, 7],
+    [9, 4, 5, 3, 1, 2, 6, 8, 7, 0],
+    [4, 2, 8, 6, 5, 7, 3, 9, 0, 1],
+    [2, 7, 9, 3, 8, 0, 6, 4, 1, 5],
+    [7, 0, 4, 6, 9, 1, 3, 2, 5, 8],
+]
+
+inverse_table = [0, 4, 3, 2, 1, 5, 6, 7, 8, 9]
+
+
+def verhoeff_checksum(number: str) -> int:
+    """Calculate the Verhoeff checksum digit."""
+    c = 0
+    n = len(number)
+    for i in range(n):
+        c = multiplication_table[c][
+            permutation_table[(i + 1) % 8][int(number[n - i - 1])]
+        ]
+    return inverse_table[c]
+
+
+def generate_aadhaar_number():
+    """Generate a valid Aadhaar number using the Verhoeff algorithm."""
+    base_number = "".join([str(random.randint(0, 9)) for _ in range(11)])
+    check_digit = verhoeff_checksum(base_number)
+    return base_number + str(check_digit)
+
+
+@frappe.whitelist()
+def validate_pancard_status(pan):
+    aadhaar_number = generate_aadhaar_number()
+    url = "https://eportal.incometax.gov.in/iec/servicesapi/getEntity"
+    payload = {
+        "aadhaarNumber": aadhaar_number,
+        "pan": pan,
+        "preLoginFlag": "Y",
+        "serviceName": "linkAadhaarPreLoginService",
+    }
+    response = requests.post(url, json=payload)
+    messages = response.json().get("messages", [])
+
+    if messages and "linked to some other Aadhaar" in messages[0].get("desc", ""):
+        return "Linked"
+    elif messages and "PAN does not exist." in messages[0].get("desc", ""):
+        return "Invalid PAN"
+    elif messages and "Individual taxpayers" in messages[0].get("desc", ""):
+        return "Not an Individual Taxpayer"
+    return ""

india_compliance/public/js/utils.js

@@ -110,6 +110,26 @@ Object.assign(india_compliance, {
         return message;
     },
 
+    async set_pan_status(field){
+        const pan = field.value;
+        if (!pan || pan.length !== 10) return field.set_description("");
+
+        const { message } = await frappe.call({
+            method: "india_compliance.gst_india.overrides.party.validate_pancard_status",
+            args: { pan },
+        });
+
+        if (!message || message == "") return field.set_description("");
+
+        const STATUS_COLORS = { 'Linked': "green", 'Not-Linked': "red", "Not an Individual Taxpayer" : "red",
+            "Invalid PAN" : "red" };
+        pan_status = `<div class="d-flex indicator ${STATUS_COLORS[message] || "orange"}">
+                    Status:&nbsp;<strong>${message}</strong>
+                </div>`;
+
+        field.set_description(pan_status);
+    },
+
     validate_gst_transporter_id(transporter_id) {
         if (!transporter_id || transporter_id.length !== 15) return;