#
#  CMakeLists.txt
#
#  Copyright (C) 2018 Lorenzo Vannucci
#
#  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/>.
  

cmake_minimum_required( VERSION 2.8.12 )

# This CMakeLists.txt is configured to build the muscle module for NEST.

# name of the module, i.e. add later with -Dexternal-modules=muscle:
set( SHORT_NAME muscle )

# complete module name
set( MODULE_NAME ${SHORT_NAME}_module )

# sources
set( MODULE_SOURCES
    muscle_module.cpp muscle_module.h
    muscle_names.cpp muscle_names.h
    muscle_spindle.cpp muscle_spindle.h
    )

# header name
set( MODULE_HEADER ${MODULE_NAME}.h )

# module version
set( MODULE_VERSION_MAJOR 1 )
set( MODULE_VERSION_MINOR 0 )
set( MODULE_VERSION "${MODULE_VERSION_MAJOR}.${MODULE_VERSION_MINOR}" )

# Leave the call to "project(...)" for after the compiler is determined.

# Set the `nest-config` executable to use during configuration.
set( with-nest OFF CACHE STRING "Specify the `nest-config` executable." )

message(${with-nest})

# If it is not set, look for a `nest-config` in the PATH.
if ( NOT with-nest )
  # try find the program ourselves
  find_program( NEST_CONFIG
      NAMES nest-config
      )
  if ( NEST_CONFIG STREQUAL "NEST_CONFIG-NOTFOUND" )
    message( FATAL_ERROR "Cannot find the program `nest-config`. Specify via -Dwith-nest=... ." )
  endif ()
else ()
  set( NEST_CONFIG ${with-nest} )
endif ()

# Use `nest-config` to get the compile and installation options used with the
# NEST installation.

# Get the compiler that was used for NEST.
execute_process(
    COMMAND ${NEST_CONFIG} --compiler
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_COMPILER
    OUTPUT_STRIP_TRAILING_WHITESPACE
)

# One check on first execution, if `nest-config` is working.
if ( NOT RES_VAR EQUAL 0 )
  message( FATAL_ERROR "Cannot run `${NEST_CONFIG}`. Please specify correct `nest-config` via -Dwith-nest=... " )
endif ()

# Setting the compiler has to happen before the call to "project(...)" function.
set( CMAKE_CXX_COMPILER "${NEST_COMPILER}" )

project( ${MODULE_NAME} CXX )

# Get the install prefix.
execute_process(
    COMMAND ${NEST_CONFIG} --prefix
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_PREFIX
    OUTPUT_STRIP_TRAILING_WHITESPACE
)

# Use the `NEST_PREFIX` as `CMAKE_INSTALL_PREFIX`.
set( CMAKE_INSTALL_PREFIX "${NEST_PREFIX}" CACHE STRING "Install path prefix, prepended onto install directories." FORCE )

# Get the CXXFLAGS.
execute_process(
    COMMAND ${NEST_CONFIG} --cflags
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_CXXFLAGS
    OUTPUT_STRIP_TRAILING_WHITESPACE
)

# Get the Includes.
execute_process(
    COMMAND ${NEST_CONFIG} --includes
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_INCLUDES
    OUTPUT_STRIP_TRAILING_WHITESPACE
)
if ( NEST_INCLUDES )
  # make a cmake list
  string( REPLACE " " ";" NEST_INCLUDES_LIST "${NEST_INCLUDES}" )
  foreach ( inc_complete ${NEST_INCLUDES_LIST} )
    # if it is actually a -Iincludedir
    if ( "${inc_complete}" MATCHES "^-I.*" )
      # get the directory
      string( REGEX REPLACE "^-I(.*)" "\\1" inc "${inc_complete}" )
      # and check whether it is a directory
      if ( IS_DIRECTORY "${inc}" )
        include_directories( "${inc}" )
      endif ()
    endif ()
  endforeach ()
endif ()

# Get, if NEST is build as a (mostly) static application. If yes, also only build
# static library.
execute_process(
    COMMAND ${NEST_CONFIG} --static-libraries
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_STATIC_LIB
    OUTPUT_STRIP_TRAILING_WHITESPACE
)
if ( NEST_STATIC_LIB )
  set( BUILD_SHARED_LIBS OFF )
else ()
  set( BUILD_SHARED_LIBS ON )
endif ()

# Get all linked libraries.
execute_process(
    COMMAND ${NEST_CONFIG} --libs
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_LIBS
    OUTPUT_STRIP_TRAILING_WHITESPACE
)

# Get the data install dir.
execute_process(
    COMMAND ${NEST_CONFIG} --datadir
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_DATADIR
    OUTPUT_STRIP_TRAILING_WHITESPACE
)

# Get the documentation install dir.
execute_process(
    COMMAND ${NEST_CONFIG} --docdir
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_DOCDIR
    OUTPUT_STRIP_TRAILING_WHITESPACE
)

# Get the library install dir.
execute_process(
    COMMAND ${NEST_CONFIG} --libdir
    RESULT_VARIABLE RES_VAR
    OUTPUT_VARIABLE NEST_LIBDIR
    OUTPUT_STRIP_TRAILING_WHITESPACE
)

# on OS X
set( CMAKE_MACOSX_RPATH ON )

# Install all stuff to NEST's install directories.
set( CMAKE_INSTALL_LIBDIR ${NEST_LIBDIR}/nest CACHE STRING "object code libraries (lib/nest or lib64/nest or lib/<multiarch-tuple>/nest on Debian)" FORCE )
set( CMAKE_INSTALL_DOCDIR ${NEST_DOCDIR} CACHE STRING "documentation root (DATAROOTDIR/doc/nest)" FORCE )
set( CMAKE_INSTALL_DATADIR ${NEST_DATADIR} CACHE STRING "read-only architecture-independent data (DATAROOTDIR/nest)" FORCE )

include( GNUInstallDirs )

# CPack stuff. Required for target `dist`.
set( CPACK_GENERATOR TGZ )
set( CPACK_SOURCE_GENERATOR TGZ )

set( CPACK_PACKAGE_DESCRIPTION_SUMMARY "NEST Module ${MODULE_NAME}" )
set( CPACK_PACKAGE_VENDOR "NEST Initiative (http://www.nest-initiative.org/)" )

set( CPACK_PACKAGE_VERSION_MAJOR ${MODULE_VERSION_MAJOR} )
set( CPACK_PACKAGE_VERSION_MINOR ${MODULE_VERSION_MINOR} )
set( CPACK_PACKAGE_VERSION ${MODULE_VERSION} )

set( CPACK_SOURCE_IGNORE_FILES
    "\\\\.gitignore"
    "\\\\.git/"
    "\\\\.travis\\\\.yml"

    # if we have in source builds
    "/build/"
    "/_CPack_Packages/"
    "CMakeFiles/"
    "cmake_install\\\\.cmake"
    "Makefile.*"
    "CMakeCache\\\\.txt"
    "CPackConfig\\\\.cmake"
    "CPackSourceConfig\\\\.cmake"
    )
set( CPACK_SOURCE_PACKAGE_FILE_NAME ${MODULE_NAME} )

set( CPACK_PACKAGE_INSTALL_DIRECTORY "${MODULE_NAME} ${MODULE_VERSION}" )
include( CPack )

# add make dist target
add_custom_target( dist
    COMMAND ${CMAKE_MAKE_PROGRAM} package_source
    # not sure about this... seems, that it will be removed before dist...
    # DEPENDS doc
    COMMENT "Creating a source distribution from ${MODULE_NAME}..."
    )


if ( BUILD_SHARED_LIBS )
  # When building shared libraries, also create a module for loading at runtime
  # with the `Install` command.
  add_library( ${MODULE_NAME}_module MODULE ${MODULE_SOURCES} )
  set_target_properties( ${MODULE_NAME}_module
      PROPERTIES
      COMPILE_FLAGS "${NEST_CXXFLAGS} -DLTX_MODULE"
      LINK_FLAGS "${NEST_LIBS}"
      PREFIX ""
      OUTPUT_NAME ${MODULE_NAME} )
  install( TARGETS ${MODULE_NAME}_module
      DESTINATION ${CMAKE_INSTALL_LIBDIR}
      )
endif ()

# Build dynamic/static library for standard linking from NEST.
add_library( ${MODULE_NAME}_lib ${MODULE_SOURCES} )
if ( BUILD_SHARED_LIBS )
  # Dynamic libraries are initiated by a `global` variable of the `SLIModule`,
  # which is included, when the flag `LINKED_MODULE` is set.
  target_compile_definitions( ${MODULE_NAME}_lib PRIVATE -DLINKED_MODULE )
endif ()
set_target_properties( ${MODULE_NAME}_lib
    PROPERTIES
    COMPILE_FLAGS "${NEST_CXXFLAGS}"
    LINK_FLAGS "${NEST_LIBS}"
    OUTPUT_NAME ${MODULE_NAME} )

# Install library, header and sli init files.
install( TARGETS ${MODULE_NAME}_lib DESTINATION ${CMAKE_INSTALL_LIBDIR} )
install( FILES ${MODULE_HEADER} DESTINATION ${CMAKE_INSTALL_INCLUDEDIR} )
install( DIRECTORY sli DESTINATION ${CMAKE_INSTALL_DATADIR} )

# Install help.
if ( NOT CMAKE_CROSSCOMPILING )
  add_custom_target( generate_help ALL )
  # Extract help from all source files in the source code, put them in
  # doc/help and generate a local help index in the build directory containing 
  # links to the help files.
  add_custom_command( TARGET generate_help POST_BUILD
    COMMAND python -B generate_help.py "${PROJECT_SOURCE_DIR}" "${PROJECT_BINARY_DIR}"
    COMMAND python -B generate_helpindex.py "${PROJECT_BINARY_DIR}/doc"
    WORKING_DIRECTORY "${CMAKE_INSTALL_PREFIX}/${NEST_DATADIR}/help_generator"
    COMMENT "Extracting help information; this may take a litte while."
    )
  # Copy the local doc/help directory to the global installation
  # directory for documentation.
  install( DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/doc/help"
    DESTINATION "${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_DOCDIR}"
    )
  # Update the global help index to contain all help files that are
  # located in the global installation directory for documentation.
  install( CODE
    "execute_process(
      COMMAND python -B generate_helpindex.py \"${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_DOCDIR}\"
      WORKING_DIRECTORY \"${CMAKE_INSTALL_PREFIX}/${NEST_DATADIR}/help_generator\"
    )"
    )
endif ()


message( "" )
message( "-------------------------------------------------------" )
message( "${MODULE_NAME} Configuration Summary" )
message( "-------------------------------------------------------" )
message( "" )
message( "C++ compiler         : ${CMAKE_CXX_COMPILER}" )
message( "Build static libs    : ${NEST_STATIC_LIB}" )
message( "C++ compiler flags   : ${CMAKE_CXX_FLAGS}" )
message( "NEST compiler flags  : ${NEST_CXXFLAGS}" )
message( "NEST include dirs    : ${NEST_INCLUDES}" )
message( "NEST libraries flags : ${NEST_LIBS}" )
message( "" )
message( "-------------------------------------------------------" )
message( "" )
message( "You can now build and install '${MODULE_NAME}' using" )
message( "  make" )
message( "  make install" )
message( "" )
message( "The library file lib${MODULE_NAME}.so will be installed to" )
message( "  ${CMAKE_INSTALL_FULL_LIBDIR}" )
message( "Help files will be installed to" )
message( "  ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_DOCDIR}" )
message( "" )
message( "The module can be loaded into NEST using" )
message( "  (${MODULE_NAME}) Install       (in SLI)" )
message( "  nest.Install(${MODULE_NAME})   (in PyNEST)" )
message( "" )