From b965b6bab194f8be2b46c1ca5de79951c43056cb Mon Sep 17 00:00:00 2001
From: RemiHelleboid <remi.helleboid@gmail.com>
Date: Fri, 14 Jan 2022 01:45:51 +0100
Subject: [PATCH] Modernization of the main CMakeLists.txt. It now support
 automatic fetching of nanoflan lib if it is not found on the system

---
 CMakeLists.txt | 64 ++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 49 insertions(+), 15 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index ee342ab..296ee18 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,24 +1,58 @@
-cmake_minimum_required(VERSION 2.8)
+cmake_minimum_required(VERSION 3.1)
+
+project(
+  KernelDensityEstimation
+  VERSION "1.0.0"
+  DESCRIPTION ""
+  LANGUAGES C CXX)
+
+include(FetchContent)
+
+option(ENABLE_BUILD_TEST "Build the tests of the project" OFF)
+option(ENABLE_BUILD_BENCHMARKS "Build the tests of the project" OFF)
+option(ENABLE_BUILD_DEMO "Build the tests of the project" OFF)
 
 # Guard against in-source builds (got this from Eigen)
-IF(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_BINARY_DIR})
-  message(FATAL_ERROR "In-source builds not allowed. Please make a new directory (called a build directory) and run CMake from there. You may need to remove CMakeCache.txt. ")
-ENDIF()
+if(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_BINARY_DIR})
+  message(
+    FATAL_ERROR
+      "In-source builds not allowed. Please make a new directory (called a build directory) and run CMake from there. You may need to remove CMakeCache.txt. "
+  )
+endif()
 
 set(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake)
 
-FIND_PACKAGE(Eigen3 REQUIRED)
-find_package(nanoflann REQUIRED)
+FetchContent_Declare(
+  nanoflann
+  GIT_REPOSITORY "https://github.com/jlblancoc/nanoflann"
+  GIT_TAG "b3e81831b847a77473e0da2ad7ee266b4f4e0d9a")
+
+# Get nanoflan lib
+find_package(nanoflann)
+if(NOT nanoflann_FOUND)
+  message("Fetching ynanoflann lib ...")
+  FetchContent_MakeAvailable(nanoflann)
+endif()
+
+find_package(Eigen3 REQUIRED)
+
+set(CMAKE_CXX_FLAGS
+    "${CMAKE_CXX_FLAGS} -std=c++11 -pedantic -Wall -Wextra -Wfatal-errors")
 
-include_directories(${EIGEN3_INCLUDE_DIR})
-include_directories(${NANOFLANN_INCLUDE_DIR})
-include_directories(${CMAKE_SOURCE_DIR})
+if(ENABLE_BUILD_TEST)
+  enable_testing()
+  add_subdirectory(test)
+endif(ENABLE_BUILD_TEST)
 
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -pedantic -Wall -Wextra -Wfatal-errors")
+if(ENABLE_BUILD_BENCHMARKS)
+  add_subdirectory(bench)
+endif(ENABLE_BUILD_BENCHMARKS)
 
-ENABLE_TESTING()
+if(ENABLE_BUILD_DEMO)
+  add_subdirectory(data)
+  add_subdirectory(demo)
+endif(ENABLE_BUILD_DEMO)
 
-add_subdirectory(test)
-add_subdirectory(bench)
-add_subdirectory(data)
-add_subdirectory(demo)
+add_library(KernelDensityEstimation INTERFACE)
+target_include_directories(KernelDensityEstimation INTERFACE src/)
+target_link_libraries(KernelDensityEstimation INTERFACE Eigen3 nanoflann)