#include <catch2/catch_test_macros.hpp>
#include "mfem/mesh/mesh.hpp"

#include "serif/backend/mfem/discretization/topology.hpp"
#include "serif/discretization/domain/physical_domains.hpp"
#include "serif/discretization/domain/relation/relations.hpp"
#include "serif/discretization/domain/relation/validation/runtime.hpp"
#include "serif/discretization/domain/schema/schemas.hpp"
#include "serif/discretization/domain/schema/validation/connected.hpp"
#include "serif/discretization/domain/types.hpp"

#include "serif/tests/test_tags.hpp"
#include "serif/tests/discritization/domain/domain_test_utils.hpp"

namespace domain     = serif::discretization::domain;
namespace relation   = domain::relation;
namespace schema     = domain::schema;
namespace validation = schema::validation;

using domain::mesh::MeshTopology;
using serif::backend::mfem::discretization::make_mesh_topology;

TEST_CASE(
    "Connected Accepts Face Connected Atomic And Composite Domains",
    tags::unit &tags::mesh &tags::utils &tags::domain
) {
    const mfem::Mesh mesh    = domain_test_utils::make_layered_mesh();
    const MeshTopology topology = make_mesh_topology(mesh);

    const auto coreResult = validation::RelationValidator<relation::FullyConnected<domain::CoreDomain>>::template validate<schema::CoreEnvelopeVacuumDomainSchema>(topology);

    REQUIRE(coreResult);
    REQUIRE(coreResult.connectedDiagnostics.has_value());
    CHECK(coreResult.connectedDiagnostics->domainElementCount == 1);
    CHECK(coreResult.connectedDiagnostics->visitedElementCount == 1);

    const auto stellarResult = validation::RelationValidator<relation::FullyConnected<domain::StellarDomains>>::template validate<schema::CoreEnvelopeVacuumDomainSchema>(topology);

    REQUIRE(stellarResult);
    REQUIRE(stellarResult.connectedDiagnostics.has_value());
    CHECK(stellarResult.connectedDiagnostics->domainElementCount == 9);
    CHECK(stellarResult.connectedDiagnostics->visitedElementCount == 9);
}

TEST_CASE(
    "Connected Rejects An Absent Domain",
    tags::unit &tags::mesh &tags::utils &tags::domain
) {
    const mfem::Mesh mesh = domain_test_utils::make_grid_mesh(2, 1, {2, 2}, {});

    const auto result = validation::RelationValidator<relation::FullyConnected<domain::CoreDomain>>::template validate<schema::CoreEnvelopeVacuumDomainSchema>(make_mesh_topology(mesh));

    CHECK_FALSE(result);
    CHECK(result.failure == validation::RelationValidationFailure::DomainAbsent);
    REQUIRE(result.connectedDiagnostics.has_value());
    CHECK(result.connectedDiagnostics->domainElementCount == 0);
    CHECK(result.connectedDiagnostics->visitedElementCount == 0);
}

TEST_CASE(
    "Connected Rejects Multiple Face Disconnected Components",
    tags::unit &tags::mesh &tags::utils &tags::domain
) {
    const mfem::Mesh mesh = domain_test_utils::make_grid_mesh(3, 1, {1, 2, 1}, {});

    const auto result = validation::RelationValidator<relation::FullyConnected<domain::CoreDomain>>::template validate<schema::CoreEnvelopeVacuumDomainSchema>(make_mesh_topology(mesh));

    CHECK_FALSE(result);
    CHECK(result.failure == validation::RelationValidationFailure::DomainDisconnected);
    REQUIRE(result.connectedDiagnostics.has_value());
    CHECK(result.connectedDiagnostics->domainElementCount == 2);
    CHECK(result.connectedDiagnostics->visitedElementCount == 1);
    CHECK(result.connectedDiagnostics->elementID >= 0);
}