if (CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
  set(VTK_USE_DAWN_WEBGPU OFF)
else ()
  set(VTK_USE_DAWN_WEBGPU ON)
endif ()

set(classes
  vtkWebGPUActor
  vtkWebGPUBatchedPolyDataMapper
  vtkWebGPUCamera
  vtkWebGPUCellToPrimitiveConverter
  vtkWebGPUCommandEncoderDebugGroup
  vtkWebGPUCompositePolyDataMapperDelegator
  vtkWebGPUComputeBuffer
  vtkWebGPUComputeFrustumCuller
  vtkWebGPUComputeOcclusionCuller
  vtkWebGPUComputePass
  vtkWebGPUComputePipeline
  vtkWebGPUComputePointCloudMapper
  vtkWebGPUComputeRenderBuffer
  vtkWebGPUComputeRenderTexture
  vtkWebGPUComputeTexture
  vtkWebGPUComputeTextureView
  vtkWebGPUConfiguration
  vtkWebGPUGlyph3DMapper
  vtkWebGPUHardwareSelector
  vtkWebGPUHelpers
  vtkWebGPULight
  vtkWebGPURenderWindow
  vtkWebGPURenderPipelineCache
  vtkWebGPUPolyDataMapper
  vtkWebGPUPolyDataMapper2D
  vtkWebGPUProperty
  vtkWebGPURenderer
  vtkWebGPUShaderDatabase
  vtkWebGPUShaderProperty
  vtkWebGPUTexture
  vtkWebGPUTextureView)

set(private_headers
  "Private/vtkWebGPUActorInternals.h"
  "Private/vtkWebGPUBindGroupInternals.h"
  "Private/vtkWebGPUBindGroupLayoutInternals.h"
  "Private/vtkWebGPUBufferInternals.h"
  "Private/vtkWebGPUComputeBufferInternals.h"
  "Private/vtkWebGPUComputePassInternals.h"
  "Private/vtkWebGPUComputePassTextureStorageInternals.h"
  "Private/vtkWebGPUComputePassBufferStorageInternals.h"
  "Private/vtkWebGPUConfigurationInternals.h"
  "Private/vtkWebGPUPipelineLayoutInternals.h"
  "Private/vtkWebGPUPointCloudMapperInternals.h"
  "Private/vtkWebGPUPolyDataMapper2DInternals.h"
  "Private/vtkWebGPURenderPassCreateInfoInternals.h"
  "Private/vtkWebGPURenderPassDescriptorInternals.h"
  "Private/vtkWebGPURenderPipelineDescriptorInternals.h"
  "Private/vtkWebGPUShaderModuleInternals.h"
  "Private/vtkWebGPUTextureInternals.h")

set(private_sources
  "Private/vtkWebGPUBindGroupInternals.cxx"
  "Private/vtkWebGPUBindGroupLayoutInternals.cxx"
  "Private/vtkWebGPUBufferInternals.cxx"
  "Private/vtkWebGPUComputeBufferInternals.cxx"
  "Private/vtkWebGPUComputePassInternals.cxx"
  "Private/vtkWebGPUComputePassTextureStorageInternals.cxx"
  "Private/vtkWebGPUComputePassBufferStorageInternals.cxx"
  "Private/vtkWebGPUConfigurationInternals.cxx"
  "Private/vtkWebGPUPipelineLayoutInternals.cxx"
  "Private/vtkWebGPUPointCloudMapperInternals.cxx"
  "Private/vtkWebGPUPolyDataMapper2DInternals.cxx"
  "Private/vtkWebGPURenderPassCreateInfoInternals.cxx"
  "Private/vtkWebGPURenderPassDescriptorInternals.cxx"
  "Private/vtkWebGPURenderPipelineDescriptorInternals.cxx"
  "Private/vtkWebGPUShaderModuleInternals.cxx"
  "Private/vtkWebGPUTextureInternals.cxx")

# setup factory overrides
# NI - Not Implemented
set(webgpu_overrides
  Actor
  # NI: BillboardTextActor3D
  Camera
  CompositePolyDataMapperDelegator
  # NI: LabeledContourMapper
  HardwareSelector
  # NI: ImageMapper
  # NI: ImageSliceMapper
  Glyph3DMapper
  # NI: HyperTreeGridMapper
  Light
  # NI: PointGaussianMapper
  PolyDataMapper
  PolyDataMapper2D
  Property
  ShaderProperty
  # NI: Uniforms
  Renderer
  # NI: RenderTimerLog
  # NI: Skybox
  # NI: TextActor
  # NI: TextActor3D
  # NI: TextMapper
  # NI: Texture
)

unset(wgsl_shader_sources)
unset(private_wgsl_shader_headers)
unset(public_wgsl_shader_headers)
set(private_shader_files
  wgsl/ActorColorOptions.wgsl
  wgsl/ActorRenderOptions.wgsl
  wgsl/ActorTransform.wgsl
  wgsl/CopyDepthTextureToBuffer.wgsl
  wgsl/FrustumCullingShader.wgsl
  wgsl/OcclusionCullingCopyDepthTexture.wgsl
  wgsl/OcclusionCullingDepthMipmaps.wgsl
  wgsl/OcclusionCullingPropsCulling.wgsl
  wgsl/PointCloudMapperCopyDepthFromWindow.wgsl
  wgsl/PointCloudMapperCopyDepthToWindow.wgsl
  wgsl/PointCloudMapperShader.wgsl
  wgsl/PolyData2D.wgsl
  wgsl/SceneLight.wgsl
  wgsl/SceneTransform.wgsl
  wgsl/Utilities.wgsl
  wgsl/VTKCellToGraphicsPrimitive.wgsl
  wgsl/vtkPolyDataVSWGSL.wgsl
  wgsl/vtkPolyDataFSWGSL.wgsl)

set(public_shader_files
  Testing/Cxx/TestShaders/TestComputePassShader.wgsl
  Testing/Cxx/TestShaders/TestComputePassChainedShader.wgsl
  Testing/Cxx/TestShaders/TestComputePassUniformShader.wgsl
  Testing/Cxx/TestShaders/TestComputeTextureShader.wgsl
  Testing/Cxx/TestShaders/TestComputeModifyPointColorsShader.wgsl
  Testing/Cxx/TestShaders/TestComputeModifyPointPositionsShader.wgsl
  Testing/Cxx/TestShaders/TestComputeModifyCellColorsShader.wgsl)

foreach (file IN LISTS private_shader_files)
  vtk_encode_string(
    INPUT         "${file}"
    EXPORT_SYMBOL "VTKRENDERINGWEBGPU_EXPORT"
    EXPORT_HEADER "vtkRenderingWebGPUModule.h"
    HEADER_OUTPUT header
    SOURCE_OUTPUT source)
  list(APPEND wgsl_shader_sources
    "${source}")
  list(APPEND private_wgsl_shader_headers
    "${header}")
endforeach ()

foreach(file IN LISTS public_shader_files)
  vtk_encode_string(
    INPUT         "${file}"
    EXPORT_SYMBOL "VTKRENDERINGWEBGPU_EXPORT"
    EXPORT_HEADER "vtkRenderingWebGPUModule.h"
    HEADER_OUTPUT header
    SOURCE_OUTPUT source
    ABI_MANGLE_HEADER       "vtkABINamespace.h"
    ABI_MANGLE_SYMBOL_BEGIN "VTK_ABI_NAMESPACE_BEGIN"
    ABI_MANGLE_SYMBOL_END   "VTK_ABI_NAMESPACE_END")
  list(APPEND wgsl_shader_sources
    "${source}")
  list(APPEND public_wgsl_shader_headers
    "${header}")
endforeach()

foreach (webgpu_override IN LISTS webgpu_overrides)
  vtk_object_factory_declare(
    BASE "vtk${webgpu_override}"
    OVERRIDE "vtkWebGPU${webgpu_override}")
endforeach ()

set(generated_headers
  vtk_wgpu.h)

set(headers)

foreach (generated_header IN LISTS generated_headers)
  configure_file(
    "${CMAKE_CURRENT_SOURCE_DIR}/${generated_header}.in"
    "${CMAKE_CURRENT_BINARY_DIR}/${generated_header}"
    @ONLY)
  list(APPEND headers
    "${CMAKE_CURRENT_BINARY_DIR}/${generated_header}")
endforeach ()

# Setup factory overrides and add window system specific render windows.
# FIXME: I've only brought the X render window from https://gitlab.kitware.com/vtk/vtk/-/merge_requests/10239/commits.
# Bring in cocoa and win32 overrides as well.
# NOTE:  Supports only one override in a build. Multiple render window overrides are confusing.
if ((CMAKE_SYSTEM_NAME STREQUAL "Emscripten") AND (VTK_USE_X OR VTK_USE_COCOA OR VTK_USE_WIN32_OPENGL))
  message(FATAL_ERROR "VTK_USE_{X,COCOA,WIN32_OPENGL} is not supported with emscripten.")
endif ()
set(has_vtkRenderWindow_override 0)
set(vtk_webgpu_factory_override_classname "")
if (CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
  set(vtk_webgpu_factory_override_classname "vtkWebAssemblyWebGPURenderWindow")
  set(has_vtkRenderWindow_override 1)
elseif (VTK_USE_X)
  # Add some custom overrides
  if (NOT VTK_DEFAULT_RENDER_WINDOW_HEADLESS)
    set(vtk_webgpu_factory_override_classname "vtkXWebGPURenderWindow")
    set(has_vtkRenderWindow_override 1)
  endif ()
elseif (VTK_USE_COCOA)
  # TODO: Implement
  # set(vtk_webgpu_factory_override_classname "vtkCocoaWebGPURenderWindow")
  # set(has_vtkRenderWindow_override 1)
elseif (VTK_USE_WIN32_OPENGL) # FIXME: We need a VTK_USE_WIN32_WINDOW flag here
  # TODO: Implement
  # set(vtk_webgpu_factory_override_classname "vtkWin32WebGPURenderWindow")
  # set(has_vtkRenderWindow_override 1)
endif ()

if (NOT has_vtkRenderWindow_override)
  message(WARNING "A render window factory override was not found!"
    "This module currently supports rendering on X11 and Emscripten platforms."
    "However, you can still execute webgpu compute pipelines.")
endif ()

list (APPEND classes ${vtk_webgpu_factory_override_classname})
configure_file(
  "${CMAKE_CURRENT_SOURCE_DIR}/vtkWebGPUObjectFactoryInit.cxx.in"
  "${CMAKE_CURRENT_BINARY_DIR}/vtkWebGPUObjectFactoryInit.cxx")

if (has_vtkRenderWindow_override)
  vtk_object_factory_declare(
    BASE vtkRenderWindow
    OVERRIDE ${vtk_webgpu_factory_override_classname})
endif ()
vtk_object_factory_configure(
  SOURCE_FILE vtk_object_factory_source
  HEADER_FILE vtk_object_factory_header
  EXPORT_MACRO "VTKRENDERINGWEBGPU_EXPORT"
  EXTRA_INCLUDES "<vtkCollection.h>" "<vtkCallbackCommand.h>" "<vtkNew.h>" "<vtkObjectFactoryCollection.h>" "<iostream>" "<cstdlib>"
  INITIAL_CODE_FILE "${CMAKE_CURRENT_BINARY_DIR}/vtkWebGPUObjectFactoryInit.cxx")

vtk_module_add_module(VTK::RenderingWebGPU
  CLASSES ${classes}
  SOURCES ${vtk_object_factory_source} ${wgsl_shader_sources} ${private_sources}
  HEADERS ${headers}
  NOWRAP_HEADERS ${public_wgsl_shader_headers}
  PRIVATE_HEADERS ${vtk_object_factory_header} ${vtk_wgpu_private_headers} ${private_wgsl_shader_headers} ${private_headers})

vtk_module_compile_features(VTK::RenderingWebGPU
  PUBLIC
    cxx_std_17)

if (CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
  vtk_module_compile_options(VTK::RenderingWebGPU
    PUBLIC
      "--use-port=emdawnwebgpu")
  vtk_module_link_options(VTK::RenderingWebGPU
    PUBLIC
      "--use-port=emdawnwebgpu")
else ()
  if (VTK_USE_X)
    vtk_module_find_package(PACKAGE X11)
    vtk_module_link(VTK::RenderingWebGPU PUBLIC X11::X11)
    if (TARGET X11::Xcursor)
      vtk_module_link(VTK::RenderingWebGPU PRIVATE X11::Xcursor)
    else ()
      message(WARNING "X11::Xcursor not found; custom cursors will be ignored.")
    endif ()
    set_property(SOURCE vtkXWebGPURenderWindow.cxx APPEND
      PROPERTY
        COMPILE_DEFINITIONS "VTK_HAVE_XCURSOR=$<TARGET_EXISTS:X11::Xcursor>"
    )
  elseif (VTK_USE_COCOA)
    # TODO
  elseif (VTK_USE_WIN32_OPENGL) # FIXME: We need a VTK_USE_WIN32_WINDOW flag here
    # TODO
  endif ()
  vtk_module_find_package(PACKAGE Dawn)
  vtk_module_link(VTK::RenderingWebGPU
    PUBLIC
      dawn::webgpu_dawn)
endif ()