CMake: use udis86 from pkg-config, fallback to subproject

Only canihavesomecoffee's fork (the one the subproject uses) provides
a .pc file, so we either find the correct version or we use the
subproject.

CMakeLists.txt

@@ -25,8 +25,18 @@ message(STATUS "Gathering git info")
 execute_process(COMMAND ./scripts/generateVersion.sh
                 WORKING_DIRECTORY ${CMAKE_SOURCE_DIR})
 
-# udis
-add_subdirectory("subprojects/udis86")
+find_package(PkgConfig REQUIRED)
+
+# Try to find canihavesomecoffee's udis86 using pkgconfig vmd/udis86 does not
+# provide a .pc file and won't be detected this way
+pkg_check_modules(udis_dep IMPORTED_TARGET udis86>=1.7.2)
+
+# Fallback to subproject
+if(NOT udis_dep_FOUND)
+  add_subdirectory("subprojects/udis86")
+  include_directories("subprojects/udis86")
+  message(STATUS "udis86 dependency not found, falling back to subproject")
+endif()
 
 if(CMAKE_BUILD_TYPE)
   string(TOLOWER ${CMAKE_BUILD_TYPE} BUILDTYPE_LOWER)
@@ -47,8 +57,6 @@ else()
   set(BUILDTYPE_LOWER "release")
 endif()
 
-find_package(PkgConfig REQUIRED)
-
 pkg_get_variable(WAYLAND_PROTOCOLS_DIR wayland-protocols pkgdatadir)
 message(STATUS "Found wayland-protocols at ${WAYLAND_PROTOCOLS_DIR}")
 pkg_get_variable(WAYLAND_SCANNER_PKGDATA_DIR wayland-scanner pkgdatadir)
@@ -63,7 +71,8 @@ else()
   message(STATUS "Configuring Hyprland in Release with CMake")
 endif()
 
-include_directories(. "src/" "subprojects/udis86/" "protocols/")
+include_directories(. "src/" "protocols/")
+
 set(CMAKE_CXX_STANDARD 26)
 add_compile_options(
   -Wall
@@ -224,6 +233,11 @@ target_precompile_headers(Hyprland PRIVATE
 message(STATUS "Setting link libraries")
 
 target_link_libraries(Hyprland rt PkgConfig::aquamarine_dep PkgConfig::deps)
+if(udis_dep_FOUND)
+  target_link_libraries(Hyprland PkgConfig::udis_dep)
+else()
+  target_link_libraries(Hyprland libudis86)
+endif()
 
 # used by `make installheaders`, to ensure the headers are generated
 add_custom_target(generate-protocol-headers)
@@ -258,8 +272,7 @@ function(protocolWayland)
                  PRIVATE ${CMAKE_SOURCE_DIR}/protocols/wayland.hpp)
 endfunction()
 
-target_link_libraries(Hyprland OpenGL::EGL OpenGL::GL Threads::Threads
-                      libudis86)
+target_link_libraries(Hyprland OpenGL::EGL OpenGL::GL Threads::Threads)
 
 pkg_check_modules(hyprland_protocols_dep hyprland-protocols>=0.2.0)
 if(hyprland_protocols_dep_FOUND)