# Shared build options and warning policy for the plot project.
#
# Included by the top-level CMakeLists.txt; every subdirectory target is
# expected to run plot_apply_warnings(<target>) so the core stays warning-clean
# under -Wall -Wextra -Wpedantic -Wconversion -Wshadow.

if(CMAKE_VERSION VERSION_LESS 3.24)
  message(FATAL_ERROR "plot requires CMake 3.24 or newer (found ${CMAKE_VERSION})")
endif()

# Adapters and examples pull in third-party SDKs, so they default to OFF; the
# core library and its tests build on a bare toolchain.
option(PLOT_BUILD_TESTS "Build the plot test suite" ON)
option(PLOT_BUILD_EXAMPLES "Build the example programs" OFF)
option(PLOT_BUILD_GLFW "Build the GLFW adapter and demo" OFF)
option(PLOT_BUILD_IMGUI "Build the Dear ImGui adapter and demo" OFF)
option(PLOT_BUILD_QT6 "Build the Qt6 adapter and demo" OFF)
option(PLOT_BUILD_GTK4 "Build the GTK4 adapter and demo" OFF)

# Apply the project warning set to a first-party target. Warnings are never
# suppressed per file.
function(plot_apply_warnings target)
  if(MSVC)
    target_compile_options(${target} PRIVATE /W4 /permissive-)
  else()
    target_compile_options(${target} PRIVATE
      -Wall
      -Wextra
      -Wpedantic
      -Wconversion
      -Wshadow)
  endif()
endfunction()

# Resolves GLFW once for every target that needs it -- the GLFW host adapter and
# the Dear ImGui backend both do. Discovery follows the design spec's order:
# find_package first, pkg-config next, FetchContent only when neither can supply
# GLFW (the last resort, because it needs the network). The result is cached in
# PLOT_GLFW_DEP, so a build with several adapters enabled discovers -- and at
# worst fetches -- exactly one copy. Sets <out_var> to the target to link.
function(plot_find_glfw out_var)
  if(NOT DEFINED PLOT_GLFW_DEP)
    set(plot_glfw_dep "")

    find_package(glfw3 3.3 QUIET)
    if(TARGET glfw)
      set(plot_glfw_dep glfw)
    elseif(TARGET glfw3::glfw3)
      set(plot_glfw_dep glfw3::glfw3)
    endif()

    if(NOT plot_glfw_dep)
      find_package(PkgConfig QUIET)
      if(PkgConfig_FOUND)
        pkg_check_modules(GLFW_PC QUIET IMPORTED_TARGET glfw3)
        if(TARGET PkgConfig::GLFW_PC)
          set(plot_glfw_dep PkgConfig::GLFW_PC)
        endif()
      endif()
    endif()

    if(NOT plot_glfw_dep)
      message(STATUS "plot: glfw3 not found via find_package or pkg-config; fetching it")
      include(FetchContent)
      set(GLFW_BUILD_DOCS OFF CACHE BOOL "" FORCE)
      set(GLFW_BUILD_TESTS OFF CACHE BOOL "" FORCE)
      set(GLFW_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
      set(GLFW_INSTALL OFF CACHE BOOL "" FORCE)
      FetchContent_Declare(glfw
        GIT_REPOSITORY https://github.com/glfw/glfw.git
        GIT_TAG 3.4
        GIT_SHALLOW TRUE)
      FetchContent_MakeAvailable(glfw)
      set(plot_glfw_dep glfw)
    endif()

    set(PLOT_GLFW_DEP "${plot_glfw_dep}" CACHE INTERNAL
        "GLFW target the plot adapters link against")
    message(STATUS "plot: GLFW adapter dependency: ${plot_glfw_dep}")
  endif()

  set(${out_var} "${PLOT_GLFW_DEP}" PARENT_SCOPE)
endfunction()