project('forts-clone', 'cpp',
  version: '0.1.0',
  license: 'GPL-3.0-or-later',
  default_options: [
    'cpp_std=c++20',
    'warning_level=3',
    'buildtype=debugoptimized',
    'default_library=static',
  ],
  meson_version: '>=1.4.0',
)

cpp = meson.get_compiler('cpp')

# =============================================================================
# Dependencies (pre-built in /usr/local by Containerfile)
# =============================================================================

# SDL3 -- windowing + input (system package)
sdl3_dep = dependency('sdl3', required: true)

# bgfx -- GPU rendering (built from source in Containerfile)
# CMake on Fedora installs to lib64
bgfx_dep = cpp.find_library('bgfx', dirs: ['/usr/local/lib64', '/usr/local/lib'])
bimg_dep = cpp.find_library('bimg', dirs: ['/usr/local/lib64', '/usr/local/lib'])
bx_dep   = cpp.find_library('bx',   dirs: ['/usr/local/lib64', '/usr/local/lib'])

# Box2D v3 -- physics engine (built from source in Containerfile)
box2d_dep = cpp.find_library('box2d', dirs: ['/usr/local/lib64', '/usr/local/lib'])

# SoLoud -- audio engine (built from source in Containerfile)
soloud_dep = cpp.find_library('soloud', dirs: ['/usr/local/lib64', '/usr/local/lib'])

# ENet -- networking (built from source in Containerfile)
enet_dep = cpp.find_library('enet', dirs: ['/usr/local/lib/static', '/usr/local/lib64', '/usr/local/lib'])

# IMPORTANT: only add /usr/local/include, NOT /usr/local/include/bx etc.
# as individual paths. sys/types.h does #include <endian.h> and would
# collide with bx/endian.h if -I/usr/local/include/bx is in the path.
local_inc = include_directories('/usr/local/include')

# Lua -- scripting. Linked STATICALLY from /usr/local/lib/liblua.a (built in the
# Containerfile) so the binary needs no liblua .so at runtime and runs on the
# host regardless of its distro's lua soname. Headers come from /usr/local/include.
lua_static = cpp.find_library('lua', dirs: ['/usr/local/lib'], static: true, required: true)
m_dep      = cpp.find_library('m',  required: false)
dl_dep     = cpp.find_library('dl', required: false)
lua_dep    = declare_dependency(dependencies: [lua_static, m_dep, dl_dep])

# glm -- math (system package)
glm_dep = dependency('glm', required: true)

# sol2 -- Lua C++ bindings (header-only, installed to /usr/local/include)
sol2_dep = declare_dependency(include_directories: '/usr/local/include')

# EnTT -- ECS (header-only, installed to /usr/local/include)
entt_dep = declare_dependency(include_directories: '/usr/local/include')

# ImGui -- skipped for M0, added when debug UI is needed

# =============================================================================
# Engine library and executable
# =============================================================================

engine_inc = include_directories('src')
stb_inc    = include_directories('third_party/stb')

# Dear ImGui (dev UI) — built as its own lib with relaxed warnings.
imgui_inc = include_directories('third_party/imgui', 'third_party/imgui/backends')
imgui_lib = static_library('imgui',
  [
    'third_party/imgui/imgui.cpp',
    'third_party/imgui/imgui_draw.cpp',
    'third_party/imgui/imgui_tables.cpp',
    'third_party/imgui/imgui_widgets.cpp',
    'third_party/imgui/backends/imgui_impl_sdl3.cpp',
    'third_party/imgui/backends/imgui_impl_sdlrenderer3.cpp',
  ],
  include_directories: imgui_inc,
  dependencies: sdl3_dep,
  override_options: ['warning_level=0', 'werror=false'],
)
imgui_dep = declare_dependency(link_with: imgui_lib, include_directories: imgui_inc)

engine_src = [
  'src/engine/app.cpp',
  'src/engine/renderer.cpp',
  'src/engine/input.cpp',
  'src/engine/camera.cpp',
  'src/engine/physics.cpp',
  'src/engine/script.cpp',
  'src/engine/stb_impl.cpp',
  'src/game/build_graph.cpp',
  'src/game/data.cpp',
]

engine_deps = [
  sdl3_dep,
  bgfx_dep, bimg_dep, bx_dep,
  box2d_dep,
  soloud_dep,
  enet_dep,
  lua_dep,
  glm_dep,
  sol2_dep,
  entt_dep,
  imgui_dep,
]

extra_inc = [local_inc, stb_inc]

# Required by bx/bgfx (normally set by cmake targets; we need them manually
# since we link raw .a files).
# GCC 14+ on glibc: __BEGIN_DECLS from sys/types.h wraps bx endian.inl
# templates in extern "C". -fpermissive downgrades to warnings.
buildtype = get_option('buildtype')
bx_debug = buildtype.startswith('debug') ? '1' : '0'

extra_cpp_args = [
  '-msse4.2',
  '-DBX_CONFIG_DEBUG=@0@'.format(bx_debug),
  '-DBGFX_CONFIG_DEBUG_ANNOTATION=@0@'.format(bx_debug),
  '-DBGFX_CONFIG_MULTITHREADED=1',
  '-DBGFX_CONFIG_VIDEO=1',
  '-D__STDC_LIMIT_MACROS',
  '-D__STDC_FORMAT_MACROS',
  '-D__STDC_CONSTANT_MACROS',
]

engine_lib = static_library('engine', engine_src,
  include_directories: [engine_inc] + extra_inc,
  dependencies: engine_deps,
  cpp_args: extra_cpp_args,
)

executable('forts-clone', 'src/main.cpp',
  link_with: engine_lib,
  include_directories: [engine_inc] + extra_inc,
  dependencies: engine_deps,
  cpp_args: extra_cpp_args,
)