cmake_minimum_required(VERSION 3.16)
project(merk LANGUAGES C CXX)

# Standards
set(CMAKE_C_STANDARD 11)
set(CMAKE_C_STANDARD_REQUIRED ON)
set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
option(BUILD_SHARED_LIBS "Build shared libraries by default" OFF)

# Collect all source files under src/ (recursively).
# CONFIGURE_DEPENDS makes CMake re-scan when files are added/removed.
file(GLOB_RECURSE PROJECT_SOURCES CONFIGURE_DEPENDS
     "${CMAKE_SOURCE_DIR}/src/*.c"
     "${CMAKE_SOURCE_DIR}/src/*.cc"
     "${CMAKE_SOURCE_DIR}/src/*.cpp"
     "${CMAKE_SOURCE_DIR}/src/*.cxx")

# Decide: executable (if src/main.* exists) or library (otherwise).
set(MAIN_CANDIDATES
    "${CMAKE_SOURCE_DIR}/src/main.c"
    "${CMAKE_SOURCE_DIR}/src/main.cc"
    "${CMAKE_SOURCE_DIR}/src/main.cpp"
    "${CMAKE_SOURCE_DIR}/src/main.cxx")
set(HAVE_MAIN FALSE)
foreach(f IN LISTS MAIN_CANDIDATES)
  if(EXISTS "${f}")
    set(HAVE_MAIN TRUE)
  endif()
endforeach()

if(HAVE_MAIN)
  add_executable(merk ${PROJECT_SOURCES})
  set(TARGET_NAME merk)
else()
  add_library(${PROJECT_NAME} ${PROJECT_SOURCES})
  set(TARGET_NAME ${PROJECT_NAME})
endif()

# Public headers live in ./include
target_include_directories(${TARGET_NAME}
  PUBLIC "${CMAKE_SOURCE_DIR}/include"
)

# Sensible warnings
if(MSVC)
  target_compile_options(${TARGET_NAME} PRIVATE /W4 /permissive-)
else()
  target_compile_options(${TARGET_NAME} PRIVATE -Wall -Wextra -Wpedantic)
endif()

# Put built artifacts under build/bin and build/lib
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)

# Find and link zlib
find_package(ZLIB REQUIRED)
find_package(OpenSSL REQUIRED)

target_link_libraries(${TARGET_NAME} PRIVATE 
    ${ZLIB_LIBRARIES}
    ${OPENSSL_LIBRARIES}
)

target_include_directories(${TARGET_NAME} PRIVATE 
    ${ZLIB_INCLUDE_DIRS}
    ${OPENSSL_INCLUDE_DIR}
)