# Copyright (c) 2023 Project CHIP Authors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import("//build_overrides/build.gni")
import("//build_overrides/chip.gni")

config("imgui_config") {
  include_dirs = [
    "repo",
    "repo/backends",
  ]
  defines = [ "CHIP_IMGUI_ENABLED=1" ]

  # FUTURE: these should be parsed from `sdl2-config --cflags`
  if (current_os == "mac") {
    # Default path setup by `brew install sdl2`
    include_dirs += [ "/usr/local/include/SDL2" ]
    defines += [ "_THREAD_SAFE" ]
    ldflags = [
      "-framework",
      "OpenGL",
    ]
  } else {
    # Linux defaults
    include_dirs += [ "/usr/include/SDL2" ]
    defines += [ "_REENTRANT" ]
  }
}

source_set("imgui") {
  sources = [
    "repo/imconfig.h",
    "repo/imgui.cpp",
    "repo/imgui.h",
    "repo/imgui_draw.cpp",
    "repo/imgui_internal.h",
    "repo/imgui_tables.cpp",
    "repo/imgui_widgets.cpp",
    "repo/imstb_rectpack.h",
    "repo/imstb_textedit.h",
    "repo/imstb_truetype.h",
  ]

  # SDL2 + OPENGL3 backend enabled directly here since
  # the includes are circular (backend includes imgui)
  sources += [
    "repo/backends/imgui_impl_opengl3.cpp",
    "repo/backends/imgui_impl_opengl3.h",
    "repo/backends/imgui_impl_sdl2.cpp",
    "repo/backends/imgui_impl_sdl2.h",
  ]

  # FUTURE: SDL2 libs should be from `sdl2-config --libs`
  libs = [
    "SDL2",
    "dl",
  ]

  if (current_os == "linux") {
    libs += [ "GL" ]
  }

  public_configs = [ ":imgui_config" ]
}