FESADev/docs/implementation-plans/property-model-foundation-implementation-plan.md

Property Model Foundation Implementation Plan

Objective

Introduce a runtime Property base class for element property and section objects, then make ShellProperty and Domain use that base class consistently.

This phase keeps property objects as model data only. It does not implement shell section stiffness, constitutive matrices, assembly, solver logic, HDF5 output, or reference comparison.

Phase Overview

1. property-base-contract

   • Record the runtime property model contract and exclusions.

2. property-base-interface

   • Add PropertyKind and abstract Property.
   • Add unit tests for polymorphic use and virtual deletion.

3. shell-property-polymorphism

   • Make ShellProperty derive from Property.
   • Preserve id, material id, thickness, and positive-thickness validation.

4. domain-property-ownership

   • Change Domain property storage to std::unique_ptr<Property>.
   • Validate duplicate property ids and shell-property material references.
   • Validate element property references against runtime property storage.

5. validation-report-handoff

   • Run targeted CTest, harness self-tests, workspace validation, and whitespace checks.
   • Update handoff documents.

Runtime Property Contract

Property represents element property and section data that is owned by Domain and referenced by elements through PropertyId.

Required interface:

namespace fesa::property {

enum class PropertyKind {
    Shell
};

class Property {
public:
    virtual ~Property() = default;

    virtual PropertyId id() const noexcept = 0;
    virtual PropertyKind kind() const noexcept = 0;
};

} // namespace fesa::property

ShellProperty:

• derives from Property;
• returns PropertyKind::Shell;
• stores PropertyId, MaterialId, and thickness;
• rejects non-positive thickness;
• does not compute shell stiffness in this phase.

Domain Contract

Domain stores runtime property objects by ownership:

std::unordered_map<PropertyId, std::unique_ptr<fesa::property::Property>>

Domain validates:

• null property pointer rejection;
• duplicate property id rejection;
• missing material id for ShellProperty;
• missing property id for elements.

Hdf5ResultWriter Constraint

The adjacent Hdf5ResultWriter work requested for this slice is limited to a skeleton class only. It may expose construction and basic path access, but it must not link HDF5, create files, define result datasets, write metadata, or claim HDF5 output support.

Non-Goals

• No MITC4 element formulation.
• No shell section stiffness.
• No material constitutive behavior.
• No DofManager work.
• No assembly, solver, sparse matrix, or reaction recovery.
• No HDF5 file writing or result schema implementation.
• No parser/factory implementation.

Tests

Primary C++ tests:

• /tests/property/property_base_test.cpp
• /tests/property/shell_property_test.cpp
• /tests/core/domain_storage_test.cpp
• /tests/core/domain_model_object_test.cpp

Required validation:

ctest --test-dir build/msvc-debug --output-on-failure -C Debug -R "domain|model-object"
python -m unittest discover -s scripts -p "test_*.py"
python scripts/validate_workspace.py
git diff --check