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cmake_minimum_required(VERSION 3.20)
project(MyProject VERSION 1.0.0 LANGUAGES CXX)

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

add_executable(myapp
    src/main.cpp
    src/utils.cpp
)

target_include_directories(myapp PRIVATE
    ${CMAKE_SOURCE_DIR}/include
)

# Static library
add_library(mylib STATIC
    src/lib.cpp
)

# Shared library
add_library(mylib_shared SHARED
    src/lib.cpp
)

# Header-only
add_library(mylib_header INTERFACE)

target_include_directories(mylib PUBLIC
    $<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/include>
    $<INSTALL_INTERFACE:include>
)

# Link library
target_link_libraries(myapp PRIVATE mylib)

# Find installed package
find_package(OpenSSL REQUIRED)
find_package(Boost 1.80 REQUIRED COMPONENTS filesystem system)
find_package(Threads REQUIRED)

target_link_libraries(myapp PRIVATE
    OpenSSL::SSL
    OpenSSL::Crypto
    Boost::filesystem
    Threads::Threads
)

include(FetchContent)

FetchContent_Declare(
    googletest
    GIT_REPOSITORY https://github.com/google/googletest.git
    GIT_TAG v1.14.0
)

FetchContent_Declare(
    json
    URL https://github.com/nlohmann/json/releases/download/v3.11.2/json.tar.xz
)

FetchContent_MakeAvailable(googletest json)

target_link_libraries(myapp PRIVATE
    GTest::gtest_main
    nlohmann_json::nlohmann_json
)

# Set variable
set(MY_VAR "value")
set(MY_LIST "a" "b" "c")

# Cache variable (user-configurable)
set(MY_OPTION "default" CACHE STRING "Description")

# Option (boolean)
option(ENABLE_TESTS "Build tests" ON)

# Conditional
if(ENABLE_TESTS)
    enable_testing()
    add_subdirectory(tests)
endif()

# Environment variable
set(ENV{PATH} "$ENV{PATH}:/new/path")

# Paths
${CMAKE_SOURCE_DIR}          # Root source
${CMAKE_BINARY_DIR}          # Build directory
${CMAKE_CURRENT_SOURCE_DIR}  # Current CMakeLists.txt dir
${PROJECT_SOURCE_DIR}        # Project root

# System
${CMAKE_SYSTEM_NAME}         # Linux, Windows, Darwin
${CMAKE_CXX_COMPILER_ID}     # GNU, Clang, MSVC

# Build type
${CMAKE_BUILD_TYPE}          # Debug, Release, etc.

# Compiler flags
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
set(CMAKE_CXX_FLAGS_DEBUG "-g -O0")
set(CMAKE_CXX_FLAGS_RELEASE "-O3 -DNDEBUG")

enable_testing()

add_executable(test_main
    tests/test_main.cpp
)

target_link_libraries(test_main PRIVATE
    mylib
    GTest::gtest_main
)

include(GoogleTest)
gtest_discover_tests(test_main)

# Or manual test
add_test(NAME MyTest COMMAND test_main)
add_test(NAME ScriptTest COMMAND ${CMAKE_SOURCE_DIR}/test.sh)

install(TARGETS mylib myapp
    EXPORT MyProjectTargets
    LIBRARY DESTINATION lib
    ARCHIVE DESTINATION lib
    RUNTIME DESTINATION bin
    INCLUDES DESTINATION include
)

install(DIRECTORY include/
    DESTINATION include
)

install(FILES ${CMAKE_BINARY_DIR}/config.h
    DESTINATION include
)

# Export for find_package
install(EXPORT MyProjectTargets
    FILE MyProjectTargets.cmake
    NAMESPACE MyProject::
    DESTINATION lib/cmake/MyProject
)