# Copyright 2012-2020 Osmocom Project
  #
  # This file is part of rtl-sdr
  #
  # This program is free software: you can redistribute it and/or modify
  # it under the terms of the GNU General Public License as published by
  # the Free Software Foundation, either version 2 of the License, or
  # (at your option) any later version.
  #
  # This program is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  # GNU General Public License for more details.
  #
  # You should have received a copy of the GNU General Public License
  # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  
  
  ########################################################################
  # Project setup
  ########################################################################
  cmake_minimum_required(VERSION 3.7.2)
  
  # workaround for https://gitlab.kitware.com/cmake/cmake/issues/16967
  if(${CMAKE_VERSION} VERSION_LESS "3.12.0")
      project(rtlsdr)
  else()
      project(rtlsdr C)
  endif()
  
  #select the release build type by default to get optimization flags
  if(NOT CMAKE_BUILD_TYPE)
     set(CMAKE_BUILD_TYPE "Release")
     message(STATUS "Build type not specified: defaulting to release.")
  endif(NOT CMAKE_BUILD_TYPE)
  
  list(APPEND CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake/Modules)
  
  include(GNUInstallDirs)
  include(GenerateExportHeader)
  include(CMakePackageConfigHelpers)
  
  # Set the version information here
  set(VERSION_INFO_MAJOR_VERSION 0) # increment major on api compatibility changes
  set(VERSION_INFO_MINOR_VERSION 6) # increment minor on feature-level changes
  set(VERSION_INFO_PATCH_VERSION git) # increment patch for bug fixes and docs
  include(Version) # setup version info
  
  ########################################################################
  # Compiler specific setup
  ########################################################################
  if(CMAKE_COMPILER_IS_GNUCC AND NOT WIN32)
      ADD_DEFINITIONS(-Wall)
      ADD_DEFINITIONS(-Wextra)
      ADD_DEFINITIONS(-Wno-unused-parameter)
      ADD_DEFINITIONS(-Wno-unused)
      ADD_DEFINITIONS(-Wsign-compare)
      ADD_DEFINITIONS(-Wdeclaration-after-statement)
      #http://gcc.gnu.org/wiki/Visibility
      add_definitions(-fvisibility=hidden)
  elseif(MSVC14 OR MSVC14)
  #pthread-w32 issue, timespec is now part of time.h
      ADD_DEFINITIONS(-D_TIMESPEC_DEFINED)
  endif()
  
  ########################################################################
  # Find build dependencies
  ########################################################################
  find_package(Threads)
  find_package(PkgConfig)
  
  if(PKG_CONFIG_FOUND)
      pkg_check_modules(LIBUSB libusb-1.0 IMPORTED_TARGET)
  else()
      set(LIBUSB_LIBRARIES "" CACHE STRING "manual libusb path")
      set(LIBUSB_INCLUDE_DIRS "" CACHE STRING "manual libusb includepath")
  endif()
  
  if(MSVC)
      set(THREADS_PTHREADS_LIBRARY "" CACHE STRING "manual pthread-win32 path")
      set(THREADS_PTHREADS_INCLUDE_DIR "" CACHE STRING "manual pthread-win32 includepath")
  else()
      set(THREADS_PTHREADS_LIBRARY "" CACHE INTERNAL "manual pthread-win32 path")
      set(THREADS_PTHREADS_INCLUDE_DIR "" CACHE INTERNAL "manual pthread-win32 includepath")
  endif()
  
  if(PKG_CONFIG_FOUND AND NOT LIBUSB_FOUND)
      message(FATAL_ERROR "LibUSB 1.0 required to compile rtl-sdr")
  endif()
  if(NOT THREADS_FOUND)
      message(FATAL_ERROR "pthreads(-win32) required to compile rtl-sdr")
  endif()
  
  ########################################################################
  # Create uninstall target
  ########################################################################
  configure_file(
      ${PROJECT_SOURCE_DIR}/cmake/cmake_uninstall.cmake.in
      ${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake
  @ONLY)
  
  add_custom_target(uninstall
      ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake
  )
  
  ########################################################################
  # Install udev rules
  ########################################################################
  option(INSTALL_UDEV_RULES "Install udev rules for RTL-SDR" OFF)
  if (INSTALL_UDEV_RULES)
      install (
          FILES rtl-sdr.rules
          DESTINATION "/etc/udev/rules.d"
          COMPONENT "udev"
          )
  else (INSTALL_UDEV_RULES)
      message (STATUS "Udev rules not being installed, install them with -DINSTALL_UDEV_RULES=ON")
  endif (INSTALL_UDEV_RULES)
  
  option(DETACH_KERNEL_DRIVER "Detach kernel driver if loaded" OFF)
  if (DETACH_KERNEL_DRIVER)
      message (STATUS "Building with kernel driver detaching enabled")
      add_definitions(-DDETACH_KERNEL_DRIVER=1)
  else (DETACH_KERNEL_DRIVER)
      message (STATUS "Building with kernel driver detaching disabled, use -DDETACH_KERNEL_DRIVER=ON to enable")
  endif (DETACH_KERNEL_DRIVER)
  
  option(ENABLE_ZEROCOPY "Enable usbfs zero-copy support" OFF)
  if (ENABLE_ZEROCOPY)
      message (STATUS "Building with usbfs zero-copy support enabled")
      add_definitions(-DENABLE_ZEROCOPY=1)
  else (ENABLE_ZEROCOPY)
      message (STATUS "Building with usbfs zero-copy support disabled, use -DENABLE_ZEROCOPY=ON to enable")
  endif (ENABLE_ZEROCOPY)
  
  ########################################################################
  # Install public header files
  ########################################################################
  install(FILES
      include/rtl-sdr.h
      include/rtl-sdr_export.h
      DESTINATION include
  )
  
  ########################################################################
  # Add subdirectories
  ########################################################################
  add_subdirectory(src)
  
  ########################################################################
  # Create Pkg Config File
  ########################################################################
  FOREACH(inc ${LIBUSB_INCLUDEDIR})
      LIST(APPEND RTLSDR_PC_CFLAGS "-I${inc}")
  ENDFOREACH(inc)
  
  FOREACH(lib ${LIBUSB_LIBRARY_DIRS})
      LIST(APPEND RTLSDR_PC_LIBS "-L${lib}")
  ENDFOREACH(lib)
  
  # use space-separation format for the pc file
  STRING(REPLACE ";" " " RTLSDR_PC_CFLAGS "${RTLSDR_PC_CFLAGS}")
  STRING(REPLACE ";" " " RTLSDR_PC_LIBS "${RTLSDR_PC_LIBS}")
  
  # unset these vars to avoid hard-coded paths to cross environment
  IF(CMAKE_CROSSCOMPILING)
      UNSET(RTLSDR_PC_CFLAGS)
      UNSET(RTLSDR_PC_LIBS)
  ENDIF(CMAKE_CROSSCOMPILING)
  
  set(prefix "${CMAKE_INSTALL_PREFIX}")
  set(exec_prefix \${prefix})
  set(includedir \${prefix}/include)
  set(libdir \${exec_prefix}/lib)
  
  CONFIGURE_FILE(
      ${CMAKE_CURRENT_SOURCE_DIR}/librtlsdr.pc.in
      ${CMAKE_CURRENT_BINARY_DIR}/librtlsdr.pc
  @ONLY)
  
  INSTALL(
      FILES ${CMAKE_CURRENT_BINARY_DIR}/librtlsdr.pc
      DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig
  )
  
  ########################################################################
  # Create CMake Config File
  ########################################################################
  write_basic_package_version_file(
    "${CMAKE_CURRENT_BINARY_DIR}/rtlsdr/rtlsdrConfigVersion.cmake"
    VERSION ${VERSION}
    COMPATIBILITY AnyNewerVersion
    )
  
  configure_file(cmake/rtlsdrConfig.cmake
    "${CMAKE_CURRENT_BINARY_DIR}/rtlsdr/rtlsdrConfig.cmake"
    COPYONLY
    )
  
  set(ConfigPackageLocation lib/cmake/rtlsdr)
  install(EXPORT RTLSDR-export
    FILE rtlsdrTargets.cmake
    NAMESPACE rtlsdr::
    DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/rtlsdr/
    )
  install(
    FILES
    cmake/rtlsdrConfig.cmake
    "${CMAKE_CURRENT_BINARY_DIR}/rtlsdr/rtlsdrConfigVersion.cmake"
    DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/rtlsdr/
    COMPONENT Devel
    )
  
  ########################################################################
  # Print Summary
  ########################################################################
  MESSAGE(STATUS "Building for version: ${VERSION} / ${LIBVER}")
  MESSAGE(STATUS "Using install prefix: ${CMAKE_INSTALL_PREFIX}")