CMakeLists.txt

cmake_minimum_required(VERSION 3.20)

# Build options (set before project() so vcpkg manifest features can be mapped)
option(FLUXGRAPH_BUILD_TESTS "Build unit tests" ON)
option(FLUXGRAPH_BUILD_EXAMPLES "Build examples" ON)
option(FLUXGRAPH_BUILD_SERVER "Build gRPC server" OFF)
option(FLUXGRAPH_BUILD_DIAGRAM_TOOL "Build diagram generation tooling" OFF)
option(FLUXGRAPH_JSON_ENABLED "Enable JSON graph loading (requires nlohmann/json)" OFF)
option(FLUXGRAPH_YAML_ENABLED "Enable YAML graph loading (requires yaml-cpp)" OFF)

# Map CMake options -> vcpkg manifest features for deterministic dependency resolution.
if(FLUXGRAPH_BUILD_TESTS)
    list(APPEND VCPKG_MANIFEST_FEATURES "tests")
endif()

if(FLUXGRAPH_BUILD_SERVER)
    list(APPEND VCPKG_MANIFEST_FEATURES "server")
endif()

if(FLUXGRAPH_JSON_ENABLED)
    list(APPEND VCPKG_MANIFEST_FEATURES "json")
endif()

if(FLUXGRAPH_YAML_ENABLED)
    list(APPEND VCPKG_MANIFEST_FEATURES "yaml")
endif()

project(fluxgraph VERSION 1.0.6 LANGUAGES CXX)

include(GNUInstallDirs)
include(CMakePackageConfigHelpers)

# C++20 required (std::format for diagnostics; standard, no third-party dep)
set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)

# Export compile commands for IDE support
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

# ThreadSanitizer (TSAN) — data-race detection for the gRPC server's worker
# threads. Applied to all targets; deps are rebuilt with TSAN via x64-linux-tsan.
option(ENABLE_TSAN "Enable ThreadSanitizer for data race detection" OFF)

if(ENABLE_TSAN)
    if(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
        if(NOT WIN32)
            add_compile_options(-fsanitize=thread -g -fno-omit-frame-pointer)
            add_link_options(-fsanitize=thread)
            message(STATUS "ThreadSanitizer (TSAN) enabled for data race detection")
        else()
            message(WARNING "ThreadSanitizer not supported on Windows (Linux/macOS only)")
        endif()
    else()
        message(WARNING "ThreadSanitizer requested but compiler not supported: ${CMAKE_CXX_COMPILER_ID}")
    endif()
elseif(DEFINED VCPKG_TARGET_TRIPLET AND VCPKG_TARGET_TRIPLET MATCHES "tsan")
    if(NOT WIN32)
        message(STATUS "ThreadSanitizer auto-detected via triplet: ${VCPKG_TARGET_TRIPLET}")
        add_compile_options(-fsanitize=thread -g -fno-omit-frame-pointer)
        add_link_options(-fsanitize=thread)
    endif()
endif()

# Fuzzing (libFuzzer, requires clang). Include the helper BEFORE the targets so
# its instrumentation applies to the code-under-test (the loaders), not just the
# harness.
option(ENABLE_FUZZING "Build libFuzzer fuzz targets (requires clang)" OFF)
if(ENABLE_FUZZING)
    include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/AddFuzzTarget.cmake)
endif()

# Core library sources
set(FLUXGRAPH_SOURCES
    src/core/signal_store.cpp
    src/core/namespace.cpp
    src/core/units.cpp
    src/model/thermal_integration.cpp
    src/model/thermal_mass.cpp
    src/model/thermal_rc2.cpp
    src/model/first_order_process.cpp
    src/model/second_order_process.cpp
    src/model/state_space_siso_discrete.cpp
    src/model/mass_spring_damper.cpp
    src/model/dc_motor.cpp
    src/graph/param_utils.cpp
    src/graph/compiler.cpp
    src/graph/compiler/algorithms.cpp
    src/graph/compiler/common.cpp
    src/graph/compiler/dimensional.cpp
    src/graph/compiler/registry_common.cpp
    src/graph/compiler/registry_transforms.cpp
    src/graph/compiler/registry_models_thermal.cpp
    src/graph/compiler/registry_models_control.cpp
    src/graph/compiler/registry_models_state_space.cpp
    src/graph/compiler/registry_models_mechanical.cpp
    src/graph/compiler/registry_models_electromechanical.cpp
    src/graph/compiler/registry.cpp
    src/engine.cpp
)

# Conditionally add loader sources and resolve dependencies from vcpkg
if(FLUXGRAPH_JSON_ENABLED)
    list(APPEND FLUXGRAPH_SOURCES src/loaders/json_loader.cpp)
    find_package(nlohmann_json CONFIG REQUIRED)
endif()

if(FLUXGRAPH_YAML_ENABLED)
    list(APPEND FLUXGRAPH_SOURCES src/loaders/yaml_loader.cpp)
    find_package(yaml-cpp CONFIG REQUIRED)
endif()

# Create static library
add_library(fluxgraph STATIC ${FLUXGRAPH_SOURCES})

# Public include directory
target_include_directories(fluxgraph PUBLIC
    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
    $<INSTALL_INTERFACE:include>
)

# Compiler warnings
if(MSVC)
    target_compile_options(fluxgraph PRIVATE /W4 /WX)
elseif(ENABLE_FUZZING)
    # The fuzz lane is the first clang build of this repo; don't fail it on
    # clang-only warnings (the gcc lanes keep -Werror).
    target_compile_options(fluxgraph PRIVATE -Wall -Wextra -pedantic)
else()
    target_compile_options(fluxgraph PRIVATE -Wall -Wextra -Werror -pedantic)
endif()

# Link optional dependencies
if(FLUXGRAPH_JSON_ENABLED)
    target_link_libraries(fluxgraph PUBLIC nlohmann_json::nlohmann_json)
    target_compile_definitions(fluxgraph PUBLIC FLUXGRAPH_JSON_ENABLED)
endif()

if(FLUXGRAPH_YAML_ENABLED)
    target_link_libraries(fluxgraph PUBLIC yaml-cpp::yaml-cpp)
    target_compile_definitions(fluxgraph PUBLIC FLUXGRAPH_YAML_ENABLED)
endif()

# Optional diagram tooling
if(FLUXGRAPH_BUILD_DIAGRAM_TOOL)
    add_subdirectory(tools)
endif()

# Tests
if(FLUXGRAPH_BUILD_TESTS)
    enable_testing()
    add_subdirectory(tests)
endif()

# Examples
if(FLUXGRAPH_BUILD_EXAMPLES)
    add_subdirectory(examples)
endif()

# gRPC Server
if(FLUXGRAPH_BUILD_SERVER)
    add_subdirectory(server)
endif()

# Fuzz targets (libFuzzer; loaders must be enabled to have something to fuzz)
if(ENABLE_FUZZING)
    add_subdirectory(fuzz)
endif()

# Install/export package configuration
install(TARGETS fluxgraph
    EXPORT fluxgraphTargets
    ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
)

if(FLUXGRAPH_BUILD_DIAGRAM_TOOL)
    install(DIRECTORY include/fluxgraph
        DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
    )
else()
    install(DIRECTORY include/fluxgraph
        DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
        PATTERN "viz" EXCLUDE
    )
endif()

install(EXPORT fluxgraphTargets
    FILE fluxgraphTargets.cmake
    NAMESPACE fluxgraph::
    DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/fluxgraph
)

configure_package_config_file(
    ${CMAKE_CURRENT_SOURCE_DIR}/cmake/fluxgraphConfig.cmake.in
    ${CMAKE_CURRENT_BINARY_DIR}/fluxgraphConfig.cmake
    INSTALL_DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/fluxgraph
)

write_basic_package_version_file(
    ${CMAKE_CURRENT_BINARY_DIR}/fluxgraphConfigVersion.cmake
    VERSION ${PROJECT_VERSION}
    COMPATIBILITY SameMajorVersion
)

install(FILES
    ${CMAKE_CURRENT_BINARY_DIR}/fluxgraphConfig.cmake
    ${CMAKE_CURRENT_BINARY_DIR}/fluxgraphConfigVersion.cmake
    DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/fluxgraph
)