feat: Add sign_document model to enable rendering of sequence type sign items on signed PDFs.

models/__init__.py

@@ -2,3 +2,4 @@
 from . import sign_item_type
 from . import sign_item
 from . import sign_request
+from . import sign_document

models/sign_document.py

@@ -0,0 +1,109 @@
+# -*- coding: utf-8 -*-
+import io
+from odoo import models
+from odoo.exceptions import ValidationError
+from odoo.tools.pdf import PdfFileReader, PdfFileWriter, PdfReadError, reshape_text
+from reportlab.pdfgen import canvas
+from reportlab.pdfbase import pdfmetrics
+try:
+    from reportlab.pdfbase.pdfmetrics import stringWidth
+except ImportError:
+    stringWidth = None
+
+class SignDocument(models.Model):
+    _inherit = 'sign.document'
+
+    def render_document_with_items(self, signed_values=None, values_dict=None, final_log_hash=None):
+        base_output = super(SignDocument, self).render_document_with_items(signed_values, values_dict, final_log_hash)
+        
+        if not base_output:
+            return base_output
+
+        items_by_page = self._get_sign_items_by_page()
+        has_sequence_items = any(
+            item.type_id.item_type == 'sequence'
+            for page_items in items_by_page.values()
+            for item in page_items
+        )
+
+        if not has_sequence_items:
+            return base_output
+
+        try:
+            base_pdf = PdfFileReader(base_output, strict=False)
+        except (ValueError, PdfReadError):
+            return base_output
+            
+        if not signed_values:
+            signed_values, values_dict = self._get_preview_values()
+            
+        font = self._get_font()
+        normalFontSize = self._get_normal_font_size()
+
+        packet = io.BytesIO()
+        # Create canvas using page size similar to image logic
+        can = canvas.Canvas(packet, pagesize=self._get_page_size(base_pdf))
+
+        for p in range(0, base_pdf.getNumPages()):
+            page = base_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 = items_by_page.get(p + 1, [])
+            for item in items:
+                if item.type_id.item_type != 'sequence':
+                    continue
+                
+                value_dict = signed_values.get(item.id)
+                if not value_dict:
+                    continue
+                    
+                value = value_dict.get('value')
+                # Sequence value is just text string
+                if not value:
+                    continue
+                
+                # Render logic similar to text
+                value = reshape_text(str(value)) # Ensure string
+                can.setFont(font, height * item.height * 0.8)
+                
+                # Alignment logic
+                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)
+            
+            can.showPage()
+        
+        can.save()
+        
+        item_pdf = PdfFileReader(packet)
+        new_pdf = PdfFileWriter()
+
+        for p in range(0, base_pdf.getNumPages()):
+            page = base_pdf.getPage(p)
+            if p < item_pdf.getNumPages():
+                page.mergePage(item_pdf.getPage(p))
+            new_pdf.addPage(page)
+
+        output = io.BytesIO()
+        try:
+            new_pdf.write(output)
+        except PdfReadError:
+            raise ValidationError(self.env._("There was an issue generating the document."))
+
+        return output