Create field_model_ifc_text.py

src/django-ifc/fields/model/field_model_ifc_text.py

@@ -0,0 +1,116 @@
+# -*- coding: utf-8 -*-
+
+
+# =============================================================================
+# Docstring
+# =============================================================================
+
+"""
+Provides IFC Text Model Field Class
+===================================
+
+
+https://standards.buildingsmart.org/IFC/RELEASE/IFC2x3/TC1/HTML/ifcmeasureresource/lexical/ifctext.htm
+
+"""  # noqa E501
+
+
+# =============================================================================
+# Import
+# =============================================================================
+
+# Import | Standard Library
+
+# Import | Libraries
+from django.db import models
+from django.utils.translation import gettext_lazy as _
+
+# Import | Local Modules
+
+
+# =============================================================================
+# Variables
+# =============================================================================
+
+__all__ = ["IfcTextField", ]
+
+
+# =============================================================================
+# Classes
+# =============================================================================
+
+class IfcTextField(models.TextField):
+    """
+    IFC Text Model Field Class
+    ==========================
+
+    Custom field for IfcText, representing a textual description in IFC models.
+
+    This field is tailored to meet the IFC standard requirements for textual
+    data, such as descriptions, notes, or any other extensive textual
+    information pertinent to IFC entities. It is based on Django's TextField
+    and ensures that data stored complies with the expected format for IFC
+    text fields.
+
+    Attributes:
+        help_text (str): Guidance for input, specifying the field's use
+            according to IFC standards, displayed in admin or forms.
+
+    """
+
+    def __init__(self, *args, **kwargs):
+        kwargs['help_text'] = kwargs.get(
+            'help_text',
+            _("Enter a textual description according to IFC standards.")
+        )
+        super().__init__(*args, **kwargs)
+
+    def from_db_value(self, value: str, expression, connection) -> str:
+        """
+        Converts the value as returned by the database to a Python object.
+        It is used when fetching the value of the field from the database.
+
+        Parameters:
+            value (str): The string value from the database.
+            expression: Unused, included for compatibility with Django's
+                signature.
+            connection: Unused, included for compatibility with Django's
+                signature.
+
+        Returns:
+            str: The value as a string, or None if the value is None.
+        """
+        if value is None:
+            return value
+        return str(value)
+
+    def to_python(self, value: str) -> str:
+        """
+        Converts the value into the correct Python object. It acts as a
+        deserializer for the Django field system and is called during form
+        clean and data loading.
+
+        Parameters:
+            value (str): The value to be converted, either from the database
+                or input.
+
+        Returns:
+            str: The value as a string, ensuring it matches the expected
+                data type.
+        """
+        if isinstance(value, str) or value is None:
+            return value
+        return str(value)
+
+    def get_prep_value(self, value: str) -> str:
+        """
+        Prepares the value before saving it into the database.
+        This method ensures the text is stored correctly in the database.
+
+        Parameters:
+            value (str): The string value to be prepared.
+
+        Returns:
+            str: The value formatted for database storage.
+        """
+        return super().get_prep_value(value)