enable Doxygen in cmake

CMakeLists.txt

@@ -13,4 +13,17 @@ src/testCommandList.cpp
 )
 
 # Add include directory
-target_include_directories("Info3_Praktikum-test" PUBLIC include/)
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+target_include_directories("Info3_Praktikum-test" PUBLIC include/)
+
+
+# Doxygen documentation
+find_package(Doxygen)
+if (DOXYGEN_FOUND)
+    add_custom_target( doc_doxygen ALL
+        COMMAND ${DOXYGEN_EXECUTABLE} Doxyfile
+        WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/..
+        COMMENT "Generating API documentation with Doxygen"
+        VERBATIM )
+else (DOXYGEN_FOUND)
+    message("Doxygen need to be installed to generate the doxygen documentation")
+endif (DOXYGEN_FOUND)
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