[ADD] stamp_sign: add company stamp field

This commit introduces the stamp_sign module, which adds a new Stamp
field type to the core Sign application.

before:
The Sign application only supported standard text signatures and initials.
There was no built-in way to apply a company-style stamp with structured
information like an address and logo.

after:
A new Stamp type is available in the Sign editor. Users can drag a
stamp field onto the document. During the signing process, clicking the
field opens a dialog to input company details (name, address, VAT, logo).
This information is rendered into a stamp image and applied to the
document. The final signed PDF includes stamp.

impact:
This extends the sign module with a new stamp type, improving its
utility for official business documents that require a formal company stamp.

Author: arkp-odoo

stamp_sign/__init__.py

@@ -0,0 +1,4 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import models
+from . import controllers

stamp_sign/__manifest__.py

@@ -0,0 +1,26 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+{
+    "name": "Stamp Sign",
+    "version": "1.0",
+    "depends": ["sign"],
+    "category": "Sign",
+    "author": "arkp",
+    "data": [
+        "data/sign_data.xml",
+        "views/sign_request_templates.xml",
+    ],
+    "assets": {
+        "web.assets_backend": [
+            "stamp_sign/static/src/components/sign_request/*",
+            "stamp_sign/static/src/dialogs/*",
+        ],
+        "sign.assets_public_sign": [
+            "stamp_sign/static/src/components/sign_request/*",
+            "stamp_sign/static/src/dialogs/*",
+        ],
+    },
+    "installable": True,
+    "application": True,
+    "license": "LGPL-3",
+}

stamp_sign/controllers/__init__.py

@@ -0,0 +1,3 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import main

stamp_sign/controllers/main.py

@@ -0,0 +1,84 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import http
+from odoo.addons.sign.controllers.main import Sign # type: ignore
+
+
+class Sign(Sign):
+    def get_document_qweb_context(self, sign_request_id, token, **post):
+        data = super().get_document_qweb_context(sign_request_id, token, **post)
+        current_request_item = data["current_request_item"]
+        sign_item_types = data["sign_item_types"]
+        company_logo = http.request.env.user.company_id.logo
+        if company_logo:
+            data["logo"] = "data:image/png;base64,%s" % company_logo.decode()
+        else:
+            data["logo"] = False
+
+        if current_request_item:
+            user_stamp = current_request_item._get_user_signature_asset("stamp_sign_stamp")
+            user_stamp_frame = current_request_item._get_user_signature_asset("stamp_sign_stamp_frame")
+
+            encoded_user_stamp = (
+                "data:image/png;base64,%s" % user_stamp.decode()
+                if user_stamp
+                else False
+            )
+            encoded_user_stamp_frame = (
+                "data:image/png;base64,%s" % user_stamp_frame.decode()
+                if user_stamp_frame
+                else False
+            )
+            stamp_item_type = next(
+                (
+                    item_type
+                    for item_type in sign_item_types
+                    if item_type["item_type"] == "stamp"
+                ),
+                None,
+            )
+            if stamp_item_type:
+                stamp_item_type["auto_value"] = encoded_user_stamp
+                stamp_item_type["frame_value"] = encoded_user_stamp_frame
+
+        return data
+
+    @http.route(["/sign/update_user_signature"], type="json", auth="user")
+    def update_signature(
+        self, sign_request_id, role, signature_type=None, datas=None, frame_datas=None
+    ):
+        user = http.request.env.user
+        if not user or signature_type not in [
+            "sign_signature",
+            "sign_initials",
+            "stamp_sign_stamp",
+        ]:
+            return False
+
+        sign_request_item_sudo = (
+            http.request.env["sign.request.item"]
+            .sudo()
+            .search(
+                [("sign_request_id", "=", sign_request_id), ("role_id", "=", role)],
+                limit=1,
+            )
+        )
+
+        allowed = sign_request_item_sudo.partner_id.id == user.partner_id.id
+        if not allowed:
+            return False
+        if datas:
+            user[signature_type] = datas[datas.find(",") + 1 :]
+        else:
+            # If no data, clear the field in the database
+            user[signature_type] = False
+
+        # Do the same check for the frame data
+        if frame_datas:
+            user[signature_type + "_frame"] = frame_datas[frame_datas.find(",") + 1 :]
+        else:
+            # If no frame data, clear the frame field in the database
+            user[signature_type + "_frame"] = False
+        # --- End of Corrected Block ---
+
+        return True

stamp_sign/data/sign_data.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<odoo>
+    <record model="sign.item.type" id="stamp_item_type">
+        <field name="name">Stamp</field>
+        <field name="item_type">stamp</field>
+        <field name="tip">stamp</field>
+        <field name="placeholder">Stamp</field>
+        <field name="default_width" type="float">0.300</field>
+        <field name="default_height" type="float">0.10</field>
+        <field name="icon">fa-legal</field>
+    </record>
+</odoo>

stamp_sign/models/__init__.py

@@ -0,0 +1,5 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import sign_template
+from . import res_users
+from . import sign_request

stamp_sign/models/res_users.py

@@ -0,0 +1,24 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import models, fields
+
+SIGN_USER_FIELDS = ["stamp_sign_stamp","stamp_sign_stamp_frame"]
+
+
+class ResUsers(models.Model):
+    _inherit = "res.users"
+
+    @property
+    def SELF_READABLE_FIELDS(self):
+        return super().SELF_READABLE_FIELDS + SIGN_USER_FIELDS
+
+    @property
+    def SELF_WRITEABLE_FIELDS(self):
+        return super().SELF_WRITEABLE_FIELDS + SIGN_USER_FIELDS
+
+    stamp_sign_stamp = fields.Binary(
+        string="Company Stamp", copy=False, groups="base.group_user"
+    )
+    stamp_sign_stamp_frame = fields.Binary(
+        string="Company Stamp Frame", copy=False, groups="base.group_user"
+    )