cmake_minimum_required(VERSION 3.20)
project(secsgem LANGUAGES CXX)

set(CMAKE_CXX_STANDARD 20)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)

if(NOT CMAKE_BUILD_TYPE)
  set(CMAKE_BUILD_TYPE Release)
endif()

add_compile_options(-Wall -Wextra -Wpedantic)

# --- libFuzzer (opt-in) ---------------------------------------------------
# Build with -DSECSGEM_FUZZ=ON to instrument every target with
# AddressSanitizer + UndefinedBehaviorSanitizer + libFuzzer coverage
# tracking.  Adds two fuzz executables (apps/fuzz_*.cpp) that feed
# arbitrary input to the SECS-II decoder and the SML parser
# respectively.  CI runs each for ~5 minutes in a dedicated job;
# customers don't build with this flag.
#
# Requires clang (libFuzzer is a clang feature).  CMake will switch to
# clang automatically — invoke with CC=clang CXX=clang++ to be explicit.
option(SECSGEM_FUZZ "Build libFuzzer harnesses" OFF)
if(SECSGEM_FUZZ)
  if(NOT CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
    message(FATAL_ERROR "SECSGEM_FUZZ requires clang; re-configure with CXX=clang++")
  endif()
  message(STATUS "libFuzzer enabled — -fsanitize=fuzzer-no-link,address,undefined")
  add_compile_options(-fsanitize=fuzzer-no-link,address,undefined
                       -g -O1 -fno-omit-frame-pointer)
  add_link_options(-fsanitize=address,undefined)
endif()

# --- ThreadSanitizer (opt-in) ---------------------------------------------
# Build with -DSECSGEM_TSAN=ON to instrument every target with TSan.
# Catches data races in EquipmentDataModel access from the io_context
# thread vs. application threads — the contract documented in
# INTEGRATION.md §3.  CI runs the threading-relevant tests under this
# flag in a separate lane; the default (release, no sanitizer) is what
# customers build.
option(SECSGEM_TSAN "Build with ThreadSanitizer" OFF)
if(SECSGEM_TSAN)
  message(STATUS "ThreadSanitizer enabled — debug symbols + -fsanitize=thread")
  add_compile_options(-fsanitize=thread -g -O1 -fno-omit-frame-pointer)
  add_link_options(-fsanitize=thread)
endif()

find_package(Threads REQUIRED)
find_package(yaml-cpp REQUIRED)

# --- Asio (standalone, header-only; from libasio-dev) ---------------------
find_path(ASIO_INCLUDE_DIR asio.hpp)
if(NOT ASIO_INCLUDE_DIR)
  message(FATAL_ERROR "asio.hpp not found. Install libasio-dev.")
endif()

add_library(asio INTERFACE)
target_include_directories(asio INTERFACE ${ASIO_INCLUDE_DIR})
target_compile_definitions(asio INTERFACE ASIO_STANDALONE ASIO_NO_DEPRECATED)
target_link_libraries(asio INTERFACE Threads::Threads)

# --- Core library ---------------------------------------------------------
# --- Codegen: SECS-II message catalog -> messages.hpp ---------------------
set(MESSAGES_HPP ${CMAKE_BINARY_DIR}/generated/secsgem/gem/messages.hpp)
add_custom_command(
  OUTPUT ${MESSAGES_HPP}
  COMMAND ${CMAKE_COMMAND} -E make_directory ${CMAKE_BINARY_DIR}/generated/secsgem/gem
  COMMAND python3 ${CMAKE_SOURCE_DIR}/tools/gen_messages.py
                  --catalog ${CMAKE_SOURCE_DIR}/data/messages.yaml
                  --out ${MESSAGES_HPP}
  DEPENDS ${CMAKE_SOURCE_DIR}/tools/gen_messages.py
          ${CMAKE_SOURCE_DIR}/data/messages.yaml
  COMMENT "Generating SECS-II messages.hpp from data/messages.yaml"
  VERBATIM
)
add_custom_target(generate_messages DEPENDS ${MESSAGES_HPP})

add_library(secsgem
  src/secs2/codec.cpp
  src/secs2/sml.cpp
  src/hsms/header.cpp
  src/hsms/connection.cpp
  src/secsi/header.cpp
  src/secsi/block.cpp
  src/secsi/protocol.cpp
  src/secsi/tcp_transport.cpp
  src/gem/control_state.cpp
  src/gem/communication_state.cpp
  src/gem/process_job_state.cpp
  src/gem/control_job_state.cpp
  src/gem/exception_state.cpp
  src/gem/carrier_state.cpp
  src/gem/load_port_state.cpp
  src/gem/substrate_state.cpp
  src/gem/ept_state.cpp
  src/gem/cem_objects.cpp
  src/gem/module_state.cpp
  src/gem/e84_state.cpp
  src/gem/host_handler.cpp
  src/gem/runtime.cpp
  src/gem/default_handlers.cpp
  src/config/loader.cpp
  src/config/validate.cpp
  src/endpoint.cpp
)
add_dependencies(secsgem generate_messages)
target_include_directories(secsgem PUBLIC
  include
  ${CMAKE_BINARY_DIR}/generated
)
target_link_libraries(secsgem PUBLIC asio yaml-cpp)

# --- Demo executables -----------------------------------------------------
add_executable(secs_server apps/secs_server.cpp)
target_link_libraries(secs_server PRIVATE secsgem)

add_executable(secs_client apps/secs_client.cpp)
target_link_libraries(secs_client PRIVATE secsgem)

add_executable(secs_interop_probe apps/secs_interop_probe.cpp)
target_link_libraries(secs_interop_probe PRIVATE secsgem)

add_executable(secs_conformance apps/secs_conformance.cpp)
target_link_libraries(secs_conformance PRIVATE secsgem)

add_executable(secs_bench apps/secs_bench.cpp)
target_link_libraries(secs_bench PRIVATE secsgem)

# Worked vendor example: ACME-PVD-3000.  Reads its own YAML, runs
# sensor simulators + a recipe runner + alarm monitors + EPT cycling
# + a Prometheus metrics exporter.  See examples/pvd_tool/README.md.
add_executable(pvd_tool examples/pvd_tool/main.cpp)
target_link_libraries(pvd_tool PRIVATE secsgem)

# --- gRPC daemon: secs_gemd -----------------------------------------------
# Runs the engine on a background thread and exposes proto/secsgem/v1 over
# gRPC. Opt-in and gracefully skipped where protobuf/grpc++ aren't installed,
# so the core library + tests build without them.
option(SECSGEM_DAEMON "Build the secs_gemd gRPC daemon" ON)
if(SECSGEM_DAEMON)
  find_package(Protobuf QUIET)
  find_package(PkgConfig QUIET)
  if(PkgConfig_FOUND)
    pkg_check_modules(GRPCPP QUIET IMPORTED_TARGET grpc++)
  endif()
  find_program(GRPC_CPP_PLUGIN grpc_cpp_plugin)
  if(Protobuf_FOUND AND GRPCPP_FOUND AND GRPC_CPP_PLUGIN)
    set(PROTO_DIR ${CMAKE_SOURCE_DIR}/proto)
    set(PROTO_FILE ${PROTO_DIR}/secsgem/v1/equipment.proto)
    set(PROTO_OUT ${CMAKE_BINARY_DIR}/generated)
    add_custom_command(
      OUTPUT ${PROTO_OUT}/secsgem/v1/equipment.pb.cc
             ${PROTO_OUT}/secsgem/v1/equipment.pb.h
             ${PROTO_OUT}/secsgem/v1/equipment.grpc.pb.cc
             ${PROTO_OUT}/secsgem/v1/equipment.grpc.pb.h
      COMMAND ${CMAKE_COMMAND} -E make_directory ${PROTO_OUT}
      COMMAND ${Protobuf_PROTOC_EXECUTABLE}
              --proto_path=${PROTO_DIR}
              --cpp_out=${PROTO_OUT}
              --grpc_out=${PROTO_OUT}
              --plugin=protoc-gen-grpc=${GRPC_CPP_PLUGIN}
              ${PROTO_FILE}
      DEPENDS ${PROTO_FILE}
      COMMENT "Generating gRPC C++ from equipment.proto"
      VERBATIM)
    add_executable(secs_gemd
      apps/secs_gemd.cpp
      ${PROTO_OUT}/secsgem/v1/equipment.pb.cc
      ${PROTO_OUT}/secsgem/v1/equipment.grpc.pb.cc)
    target_include_directories(secs_gemd PRIVATE ${PROTO_OUT} ${Protobuf_INCLUDE_DIRS})
    target_link_libraries(secs_gemd PRIVATE secsgem PkgConfig::GRPCPP ${Protobuf_LIBRARIES})
    set(SECSGEM_DAEMON_BUILT TRUE)
    message(STATUS "secs_gemd daemon enabled (grpc++ ${GRPCPP_VERSION})")
  else()
    message(STATUS "secs_gemd skipped (need protobuf + grpc++ + grpc_cpp_plugin)")
  endif()
endif()

if(SECSGEM_FUZZ)
  # libFuzzer entry-point targets.  Each owns its own `main` via the
  # `-fsanitize=fuzzer` link flag; do NOT also link them into the
  # regular test binary.
  add_executable(fuzz_secs2_decode apps/fuzz_secs2_decode.cpp)
  target_link_libraries(fuzz_secs2_decode PRIVATE secsgem)
  target_link_options(fuzz_secs2_decode PRIVATE -fsanitize=fuzzer)

  add_executable(fuzz_sml_parse apps/fuzz_sml_parse.cpp)
  target_link_libraries(fuzz_sml_parse PRIVATE secsgem)
  target_link_options(fuzz_sml_parse PRIVATE -fsanitize=fuzzer)
endif()

# --- Tests ----------------------------------------------------------------
enable_testing()
include(FetchContent)
FetchContent_Declare(
  doctest
  GIT_REPOSITORY https://github.com/doctest/doctest.git
  GIT_TAG        v2.4.11
)
FetchContent_MakeAvailable(doctest)

add_executable(secsgem_tests
  tests/test_main.cpp
  tests/test_secs2.cpp
  tests/test_fuzz.cpp
  tests/test_hsms.cpp
  tests/test_hsms_connection.cpp
  tests/test_hsms_timers.cpp
  tests/test_hsms_s9.cpp
  tests/test_hsms_gs.cpp
  tests/test_secsi.cpp
  tests/test_secsi_timers.cpp
  tests/test_secsi_tcp.cpp
  tests/test_host_handler.cpp
  tests/test_control_state.cpp
  tests/test_communication_state.cpp
  tests/test_data_model.cpp
  tests/test_runtime.cpp
  tests/test_default_handlers.cpp
  tests/test_name_index.cpp
  tests/test_messages.cpp
  tests/test_loader.cpp
  tests/test_process_jobs.cpp
  tests/test_control_jobs.cpp
  tests/test_job_persistence.cpp
  tests/test_exceptions.cpp
  tests/test_exception_persistence.cpp
  tests/test_carrier_state.cpp
  tests/test_carriers.cpp
  tests/test_carrier_persistence.cpp
  tests/test_substrates.cpp
  tests/test_substrate_persistence.cpp
  tests/test_ept.cpp
  tests/test_cem_objects.cpp
  tests/test_modules.cpp
  tests/test_sml.cpp
  tests/test_s9_fallback.cpp
  tests/test_e84.cpp
  tests/test_e84_ports.cpp
  tests/test_e84_timers.cpp
  tests/test_e84_asio_timers.cpp
  tests/test_e42_formatted_pp.cpp
  tests/test_gem300_scenario.cpp
  tests/test_wire_ceid_emission.cpp
  tests/test_live_gem300.cpp
  tests/test_e87_wire_scenarios.cpp
  tests/test_identifier_wildcards.cpp
  tests/test_concurrency.cpp
  tests/test_thread_safety.cpp
  tests/test_persistence_upgrade.cpp
  tests/test_config_validate.cpp
  tests/test_metrics_prometheus.cpp
  tests/test_hsms_gs_integration.cpp
  tests/test_robustness_fuzz.cpp
  tests/test_e5_kat.cpp
)
target_link_libraries(secsgem_tests PRIVATE secsgem doctest::doctest)
target_compile_definitions(secsgem_tests PRIVATE
  SECSGEM_DATA_DIR="${CMAKE_SOURCE_DIR}/data")
add_test(NAME secsgem_tests COMMAND secsgem_tests)

# Daemon gRPC integration tests (separate binary: needs grpc++ + the generated
# proto, which the core test binary doesn't link). Built only when the daemon is.
if(SECSGEM_DAEMON_BUILT)
  add_executable(secs_gemd_tests
    tests/test_daemon_service.cpp
    ${PROTO_OUT}/secsgem/v1/equipment.pb.cc
    ${PROTO_OUT}/secsgem/v1/equipment.grpc.pb.cc)
  target_include_directories(secs_gemd_tests PRIVATE
    ${PROTO_OUT} ${Protobuf_INCLUDE_DIRS} ${CMAKE_SOURCE_DIR}/apps)
  target_link_libraries(secs_gemd_tests PRIVATE
    secsgem PkgConfig::GRPCPP ${Protobuf_LIBRARIES} doctest::doctest)
  target_compile_definitions(secs_gemd_tests PRIVATE
    SECSGEM_DATA_DIR="${CMAKE_SOURCE_DIR}/data")
  add_test(NAME secs_gemd_tests COMMAND secs_gemd_tests)
endif()