cmake_minimum_required(VERSION 3.20)
project(
  arena
  VERSION 1.0
  LANGUAGES C)

# ------------------------------------------------
# C standard — no compiler extensions
# ------------------------------------------------
set(CMAKE_C_STANDARD 11)
set(CMAKE_C_STANDARD_REQUIRED ON)
set(CMAKE_C_EXTENSIONS OFF)

# Export compile_commands.json (clangd / IDEs)
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

# ------------------------------------------------
# Is this the root project or embedded (CPM / FetchContent)?
# ------------------------------------------------
if(CMAKE_SOURCE_DIR STREQUAL PROJECT_SOURCE_DIR)
  set(ARENA_IS_TOP_LEVEL ON)
else()
  set(ARENA_IS_TOP_LEVEL OFF)
endif()

# ------------------------------------------------
# Options
# ------------------------------------------------
option(ARENA_BUILD_TESTS "Build arena tests" ${ARENA_IS_TOP_LEVEL})
option(ARENA_BUILD_EXAMPLE "Build arena example" ${ARENA_IS_TOP_LEVEL})
option(ARENA_ENABLE_INSTALL "Install arena" ${ARENA_IS_TOP_LEVEL})
option(ARENA_ENABLE_SANITIZERS "Enable Address Sanitizer in tests" ON)

# ------------------------------------------------
# Portable warning flags
# ------------------------------------------------
if(MSVC)
  set(ARENA_WARNING_FLAGS /W4)
else()
  set(ARENA_WARNING_FLAGS -Wall -Wextra -Wpedantic)
endif()

# ================================================================
# LIBRARY
# ================================================================
add_library(arena src/arena.c)

# Namespaced alias → consumers can write arena::arena
add_library(arena::arena ALIAS arena)

target_include_directories(
  arena PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
               $<INSTALL_INTERFACE:include>)

# Propagate C11 requirement to consumers
target_compile_features(arena PUBLIC c_std_11)

# Warnings only for the lib itself, not propagated
target_compile_options(arena PRIVATE ${ARENA_WARNING_FLAGS})

# ================================================================
# EXAMPLE  (optional, only when top-level)
# ================================================================
if(ARENA_BUILD_EXAMPLE)
  add_executable(arena_example src/main.c)
  target_link_libraries(arena_example PRIVATE arena)
endif()

# ================================================================
# TESTS
# ================================================================
if(ARENA_BUILD_TESTS)
  enable_testing()
  add_subdirectory(test)
endif()

# ================================================================
# INSTALL
# ================================================================
if(ARENA_ENABLE_INSTALL)
  include(GNUInstallDirs)

  install(
    TARGETS arena
    EXPORT arenaTargets
    ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})

  install(DIRECTORY include/ DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})

  install(
    EXPORT arenaTargets
    FILE arenaTargets.cmake
    NAMESPACE arena::
    DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/arena)
endif()