##
# Project setup.
project(hayai)
cmake_minimum_required(VERSION 2.4)
cmake_policy(SET CMP0012 NEW)

option(INSTALL_HAYAI "Install Hayai in addition of library compilation" ON)
option(BUILD_HAYAI_TESTS "Build the tests" ON)
option(BUILD_HAYAI_SAMPLES "Build the samples" ON)

# Offer the user the choice of overriding the installation directories.
set(INSTALL_LIB_DIR lib CACHE PATH "Installation directory for libraries")
set(INSTALL_BIN_DIR bin CACHE PATH "Installation directory for executables")
set(INSTALL_INCLUDE_DIR include CACHE PATH
  "Installation directory for header files")
if(WIN32 AND NOT CYGWIN)
  set(DEF_INSTALL_CMAKE_DIR CMake)
else()
  set(DEF_INSTALL_CMAKE_DIR lib/CMake/hayai)
endif()
set(INSTALL_CMAKE_DIR ${DEF_INSTALL_CMAKE_DIR} CACHE PATH
  "Installation directory for CMake files")

# Make relative paths absolute (needed later on.)
foreach(p LIB BIN INCLUDE CMAKE)
  set(var INSTALL_${p}_DIR)
  if(NOT IS_ABSOLUTE "${${var}}")
    set(${var} "${CMAKE_INSTALL_PREFIX}/${${var}}")
  endif()
endforeach()

# Proxy external CXXFLAGS.
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} $ENV{CXXFLAGS}")
set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} $ENV{CXXFLAGS}")
set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} $ENV{CXXFLAGS}")
set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELWITHDEBINFO} $ENV{CXXFLAGS}")

# Determine system-dependant library paths.
include(CheckLibraryExists)
CHECK_LIBRARY_EXISTS(rt clock_gettime "time.h" NEED_RT_LIB)
if (${NEED_RT_LIB})
  set(LIB_TIMING "rt")
else (${NEED_RT_LIB})
  set(LIB_TIMING "")
endif (${NEED_RT_LIB})

##
# Include the individual projects.
add_subdirectory(src)

# Include the sample subdirectory if requested by user passing -BUILD_HAYAI_SAMPLES=true.
if (${BUILD_HAYAI_SAMPLES})
  add_subdirectory(sample)
endif (${BUILD_HAYAI_SAMPLES})

# Include tests if requested by the user passing -DBUILD_HAYAI_TESTS=true.
if (${BUILD_HAYAI_TESTS})
  enable_testing()

  add_subdirectory(vendor/gtest)
  add_subdirectory(tests)
endif (${BUILD_HAYAI_TESTS})

##
# Export targets and package

# Add all targets to the build-tree export set
export(
  TARGETS hayai_main
  FILE "${PROJECT_BINARY_DIR}/hayai-targets.cmake"
)

# Export the package for use from the build-tree
# (this registers the build-tree with a global CMake-registry.)
export(PACKAGE hayai)

# Install targets if requested.
if (${INSTALL_HAYAI})
  # Create the hayai-config.cmake.
  file(RELATIVE_PATH REL_INCLUDE_DIR "${INSTALL_CMAKE_DIR}"
    "${INSTALL_INCLUDE_DIR}")

  # ... for the build tree.
  set(CONF_INCLUDE_DIRS "${PROJECT_SOURCE_DIR}/src" "${PROJECT_BINARY_DIR}")
  configure_file(hayai-config.cmake.in
    "${PROJECT_BINARY_DIR}/hayai-config.cmake" @ONLY)

  # ... for the install tree.
  set(CONF_INCLUDE_DIRS "\${HAYAI_CMAKE_DIR}/${REL_INCLUDE_DIR}")
  configure_file(
    hayai-config.cmake.in
    "${PROJECT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/hayai-config.cmake" @ONLY
  )

  # Install the hayai-config.cmake
  install(
    FILES "${PROJECT_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/hayai-config.cmake"
    DESTINATION "${INSTALL_CMAKE_DIR}"
    COMPONENT dev
  )

  # Install the export set for use with the install-tree.
  install(
    EXPORT hayai-targets
    DESTINATION "${INSTALL_CMAKE_DIR}"
    COMPONENT dev
  )
endif (${INSTALL_HAYAI})

# Print build resume.
#
# This function has been adapted from the OpenCV CMake utilities.
function(print_status txt var)
  if (var)
    message(STATUS ${txt} "YES")
  else (var)
    message(STATUS ${txt} "NO")
  endif (var)
endfunction()
message(STATUS "")
message(STATUS "Hayai build resume:")
print_status("  Building tests:     " ${BUILD_HAYAI_TESTS})
print_status("  Building samples:   " ${BUILD_HAYAI_SAMPLES})
print_status("  Installing:         " ${INSTALL_HAYAI})
message(STATUS "")