[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

awesome_gallery/__manifest__.py

@@ -12,6 +12,7 @@
     'version': '0.1',
     'application': True,
     'category': 'Tutorials/AwesomeGallery',
+    'author': 'arkp',
     'installable': True,
     'depends': ['web', 'contacts'],
     'data': [

awesome_kanban/__manifest__.py

@@ -12,6 +12,7 @@
     'version': '0.1',
     'application': True,
     'category': 'Tutorials/AwesomeKanban',
+    'author': 'arkp',
     'installable': True,
     'depends': ['web', 'crm'],
     'data': [

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 +1,51 @@
+# 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)
+        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
+
+        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",
+        ]:
+            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:
+            user[signature_type] = False
+
+        if frame_datas:
+            user[signature_type + "_frame"] = frame_datas[frame_datas.find(",") + 1 :]
+        else:
+            user[signature_type + "_frame"] = False
+
+        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 +1,4 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import sign_template
+from . import sign_request

stamp_sign/models/sign_request.py

@@ -0,0 +1,228 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+import base64
+import io
+import time
+from PIL import UnidentifiedImageError
+from reportlab.lib.utils import ImageReader
+from reportlab.pdfgen import canvas
+from reportlab.lib.styles import ParagraphStyle
+from reportlab.platypus import Paragraph
+from reportlab.pdfbase.pdfmetrics import stringWidth
+from reportlab.pdfbase import pdfmetrics
+from reportlab.pdfbase.ttfonts import TTFont
+
+from odoo import _, models
+from odoo.tools import format_date, is_html_empty
+from odoo.exceptions import UserError, ValidationError
+from odoo.tools.pdf import PdfFileReader, PdfFileWriter
+from odoo.tools.misc import get_lang
+
+try:
+    from PyPDF2.errors import PdfReadError # type: ignore
+except ImportError:
+    try:
+        from PyPDF2.utils import PdfReadError
+    except ImportError:
+        PdfReadError = Exception
+
+
+def _fix_image_transparency(image):
+    pixels = image.load()
+    for x in range(image.size[0]):
+        for y in range(image.size[1]):
+            if pixels[x, y] == (0, 0, 0, 0):
+                pixels[x, y] = (255, 255, 255, 0)
+
+
+class SignRequest(models.Model):
+    _inherit = "sign.request"
+
+    def _generate_completed_document(self, password=""):
+        self.ensure_one()
+        if self.state != 'signed':
+            raise UserError(_("The completed document cannot be created because the sign request is not fully signed"))
+        if not self.template_id.sign_item_ids:
+            self.completed_document = self.template_id.attachment_id.datas
+        else:
+            try:
+                old_pdf = PdfFileReader(io.BytesIO(base64.b64decode(self.template_id.attachment_id.datas)), strict=False, overwriteWarnings=False)
+                old_pdf.getNumPages()
+            except Exception:
+                raise ValidationError(_("ERROR: Invalid PDF file!"))
+
+            isEncrypted = old_pdf.isEncrypted
+            if isEncrypted and not old_pdf.decrypt(password):
+                return
+
+            font = self._get_font()
+            normalFontSize = self._get_normal_font_size()
+
+            packet = io.BytesIO()
+            can = canvas.Canvas(packet, pagesize=self.get_page_size(old_pdf))
+            itemsByPage = self.template_id._get_sign_items_by_page()
+            items_ids = [id for items in itemsByPage.values() for id in items.ids]
+            values_dict = self.env['sign.request.item.value']._read_group(
+                [('sign_item_id', 'in', items_ids), ('sign_request_id', '=', self.id)],
+                groupby=['sign_item_id'],
+                aggregates=['value:array_agg', 'frame_value:array_agg', 'frame_has_hash:array_agg']
+            )
+            values = {
+                sign_item.id : {
+                    'value': values[0],
+                    'frame': frame_values[0],
+                    'frame_has_hash': frame_has_hashes[0],
+                }
+                for sign_item, values, frame_values, frame_has_hashes in values_dict
+            }
+
+            for p in range(0, old_pdf.getNumPages()):
+                page = old_pdf.getPage(p)
+                width = float(abs(page.mediaBox.getWidth()))
+                height = float(abs(page.mediaBox.getHeight()))
+
+                rotation = page.get('/Rotate', 0)
+                if rotation and isinstance(rotation, int):
+                    can.rotate(rotation)
+                    if rotation == 90:
+                        width, height = height, width
+                        can.translate(0, -height)
+                    elif rotation == 180:
+                        can.translate(-width, -height)
+                    elif rotation == 270:
+                        width, height = height, width
+                        can.translate(-width, 0)
+
+                items = itemsByPage[p + 1] if p + 1 in itemsByPage else []
+                for item in items:
+                    value_dict = values.get(item.id)
+                    if not value_dict:
+                        continue
+                    value = value_dict['value']
+                    frame = value_dict['frame']
+
+                    if frame:
+                        try:
+                            image_reader = ImageReader(io.BytesIO(base64.b64decode(frame[frame.find(',')+1:])))
+                        except UnidentifiedImageError:
+                            raise ValidationError(_("There was an issue downloading your document. Please contact an administrator."))
+                        _fix_image_transparency(image_reader._image)
+                        can.drawImage(
+                            image_reader,
+                            width*item.posX,
+                            height*(1-item.posY-item.height),
+                            width*item.width,
+                            height*item.height,
+                            'auto',
+                            True
+                        )
+
+                    if item.type_id.item_type == "text":
+                        can.setFont(font, height*item.height*0.8)
+                        if item.alignment == "left":
+                            can.drawString(width*item.posX, height*(1-item.posY-item.height*0.9), value)
+                        elif item.alignment == "right":
+                            can.drawRightString(width*(item.posX+item.width), height*(1-item.posY-item.height*0.9), value)
+                        else:
+                            can.drawCentredString(width*(item.posX+item.width/2), height*(1-item.posY-item.height*0.9), value)
+
+                    elif item.type_id.item_type == "selection":
+                        content = []
+                        for option in item.option_ids:
+                            if option.id != int(value):
+                                content.append("<strike>%s</strike>" % (option.value))
+                            else:
+                                content.append(option.value)
+                        font_size = height * normalFontSize * 0.8
+                        text = " / ".join(content)
+                        string_width = stringWidth(text.replace("<strike>", "").replace("</strike>", ""), font, font_size)
+                        p = Paragraph(text, ParagraphStyle(name='Selection Paragraph', fontName=font, fontSize=font_size, leading=12))
+                        posX = width * (item.posX + item.width * 0.5) - string_width // 2
+                        posY = height * (1 - item.posY - item.height * 0.5) - p.wrap(width, height)[1] // 2
+                        p.drawOn(can, posX, posY)
+
+                    elif item.type_id.item_type == "textarea":
+                        font_size = height * normalFontSize * 0.8
+                        can.setFont(font, font_size)
+                        lines = value.split('\n')
+                        y = (1-item.posY)
+                        for line in lines:
+                            empty_space = width * item.width - can.stringWidth(line, font, font_size)
+                            x_shift = 0
+                            if item.alignment == 'center':
+                                x_shift = empty_space / 2
+                            elif item.alignment == 'right':
+                                x_shift = empty_space
+                            y -= normalFontSize * 0.9
+                            can.drawString(width * item.posX + x_shift, height * y, line)
+                            y -= normalFontSize * 0.1
+
+                    elif item.type_id.item_type == "checkbox":
+                        can.setFont(font, height*item.height*0.8)
+                        value = 'X' if value == 'on' else ''
+                        can.drawString(width*item.posX, height*(1-item.posY-item.height*0.9), value)
+                    elif item.type_id.item_type == "radio":
+                        x = width * item.posX
+                        y = height * (1 - item.posY)
+                        w = item.width * width
+                        h = item.height * height
+                        c_x = x + w * 0.5
+                        c_y = y - h * 0.5
+                        can.circle(c_x, c_y, h * 0.5)
+                        if value == "on":
+                            can.circle(x_cen=c_x, y_cen=c_y, r=h * 0.5 * 0.75, fill=1)
+                    elif item.type_id.item_type in ["signature", "initial", "stamp"]:
+                        try:
+                            image_reader = ImageReader(io.BytesIO(base64.b64decode(value[value.find(',')+1:])))
+                        except UnidentifiedImageError:
+                            raise ValidationError(_("There was an issue downloading your document. Please contact an administrator."))
+                        _fix_image_transparency(image_reader._image)
+                        can.drawImage(image_reader, width*item.posX, height*(1-item.posY-item.height), width*item.width, height*item.height, 'auto', True)
+
+                can.showPage()
+
+            can.save()
+
+            item_pdf = PdfFileReader(packet, overwriteWarnings=False)
+            new_pdf = PdfFileWriter()
+
+            for p in range(0, old_pdf.getNumPages()):
+                page = old_pdf.getPage(p)
+                page.mergePage(item_pdf.getPage(p))
+                new_pdf.addPage(page)
+
+            if isEncrypted:
+                new_pdf.encrypt(password)
+
+            try:
+                output = io.BytesIO()
+                new_pdf.write(output)
+            except PdfReadError:
+                raise ValidationError(_("There was an issue downloading your document. Please contact an administrator."))
+
+            self.completed_document = base64.b64encode(output.getvalue())
+            output.close()
+
+        attachment = self.env['ir.attachment'].create({
+            'name': "%s.pdf" % self.reference if self.reference.split('.')[-1] != 'pdf' else self.reference,
+            'datas': self.completed_document,
+            'type': 'binary',
+            'res_model': self._name,
+            'res_id': self.id,
+        })
+        public_user = self.env.ref('base.public_user', raise_if_not_found=False)
+        if not public_user:
+            public_user = self.env.user
+        pdf_content, __ = self.env["ir.actions.report"].with_user(public_user).sudo()._render_qweb_pdf(
+            'sign.action_sign_request_print_logs',
+            self.ids,
+            data={'format_date': format_date, 'company_id': self.communication_company_id}
+        )
+        attachment_log = self.env['ir.attachment'].create({
+            'name': "Certificate of completion - %s.pdf" % time.strftime('%Y-%m-%d - %H:%M:%S'),
+            'raw': pdf_content,
+            'type': 'binary',
+            'res_model': self._name,
+            'res_id': self.id,
+        })
+        self.completed_document_attachment_ids = [(6, 0, [attachment.id, attachment_log.id])]

stamp_sign/models/sign_template.py

@@ -0,0 +1,9 @@
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import fields, models
+
+
+class SignItemType(models.Model):
+    _inherit = "sign.item.type"
+
+    item_type = fields.Selection(selection_add=[("stamp", "Stamp")], ondelete={"stamp": "set default"})