# Copyright 2018 Rasmus Thomsen <cogitri@exherbo.org>
# Based in part upon 'mesa.exlib' which is:
# Copyright 2008 Alexander Færøy <eroyf@eroyf.org>
# Copyright 2008-2011 Ingmar Vanhassel <ingmar@exherbo.org>
# Copyright 2013 Saleem Abdulrasool <compnerd@compnerd.org>

if ever is_scm ; then
    SCM_REPOSITORY="https://anongit.freedesktop.org/git/${PN}/${PN}.git"
    require scm-git
else
    MY_PV=${PV%%-rc*}
    DOWNLOADS="
        https://mesa.freedesktop.org/archive/${MY_PV}/${PNV}.tar.xz
        https://mesa.freedesktop.org/archive/${PNV}.tar.xz
    "
    UPSTREAM_RELEASE_NOTES="https://www.mesa3d.org/relnotes/${PV}.html"
fi

require alternatives meson [ meson_minimum_version=0.42 ]

export_exlib_phases src_prepare src_configure src_install

SUMMARY="Mesa's OpenGL library"
HOMEPAGE="https://www.mesa3d.org"

LICENCES="MIT"
SLOT="0"
MYOPTIONS="
    d3d9 [[ description = [ Gallium Direct3D 9.x state tracker ] requires = [ llvm X ] ]]
    d3d9? (
        video_drivers:
            (
                i915
                intel
                nouveau
                r300
                radeon
                vmware
            ) [[ number-selected = at-least-one ]]
    )
    gl-vendor [[
        description = [ Install a glvnd (gl vendor) file to allow for parallel install of multiple GL implementations ]
    ]]
    llvm [[ description = [ Using LLVM as the shader backend for Gallium ] ]]
    opencl [[ description = [ Enable the OpenCL Gallium state tracker ] requires = [ llvm ] ]]
    sensors [[ description = [ Gallium extra HUD and sensors support ] ]]
    sensors? ( ( video_drivers: nouveau radeon ) [[ number-selected = at-least-one ]] )
    texture-float [[ description = [ Enable floating-point textures and renderbuffers. SGI claims to hold patents on this code. ] ]]
    va [[ description = [ Enable the VA-API state tracker ] ]]
    va? (
        ( X wayland ) [[ number-selected = at-least-one ]]
        video_drivers:
            (
                nouveau
                radeon
            ) [[ number-selected = at-least-one ]]
    )
    vdpau [[ description = [ Enable support for VDPAU hardware accelerated video decoding ] requires = [ X ] ]]
    wayland
    X [[ description = [ Enable GLX ] presumed = true ]]
    xa [[ description = [ Enable the X Acceleration API (xatracker) ] ]]
    xvmc [[ description = [ Enable support for XvMC hardware accelerated video decoding ] ]]
    (
        platform:
            amd64
            x86
        video_drivers:
            (
                i915 [[ description = [ Gallium driver for i915 based Intel GPUs ] ]]
                intel [[ description = [ Driver for i915, i965 and newer ] ]]
            ) [[ number-selected = at-most-one ]]
            gallium-swrast [[
                description = [ Gallium based software driver ]
                requires = [ llvm ]
            ]]
            (
                nouveau [[ description = [ (Gallium) Generally for newer Nvidia cards ] ]]
                nouveau-legacy [[ description = [ Generally for older Nvidia cards ] ]]
            ) [[ number-selected = at-most-one ]]
            (
                r300 [[ description = [ (Gallium) Driver for Radeon cards from 9500 (r300) to X1950 (r500) ] ]]
                radeon [[ description = [ (Gallium) Driver for the Radeon HD-2000 (r600) and newer ] ]]
            ) [[ requires = [ llvm video_drivers: gallium-swrast ] ]]
            radeon-legacy [[ description = [ Classic driver for cards older than the Radeon 9500 (r300) ] ]]
            virtio-gpu [[ description = [ Gallium driver for guest systems on hypervisors with VirtIO-GPU ] ]]
            vmware [[ description = [ Gallium driver for VMware's SVGA virtual GPU ] ]]
    )
    (
        platform:
            armv7
        video_drivers:
            (
                vc4 [[ description = [ Gallium driver for Raspberry Pi Videocore graphics ] ]]
            )
    )
    llvm? (
        ( video_drivers: gallium-swrast i915 nouveau r300 radeon ) [[ number-selected = at-least-one ]]
    )
    opencl? (
        ( video_drivers: nouveau radeon ) [[ number-selected = at-least-one ]]
    )
    valgrind [[ description = [ Support valgrind intrinsics to suppress false warnings ] ]]
    vdpau? ( ( video_drivers: nouveau radeon ) [[ number-selected = at-least-one ]] )
    xa? ( ( video_drivers: i915 nouveau vmware ) [[ number-selected = at-least-one ]] )
    xvmc? ( ( video_drivers: nouveau radeon ) [[ number-selected = at-least-one ]] )
"

# NOTE(Cogitri): The below version is needed to build mesa at all
LIBDRM_REQUIRED='[>=2.4.75]'
# The below version is needed to build amdvk or radeonsi
LIBDRM_REQUIRED_AMDGPU='[>=2.4.91]'
# The below version is needed to build any of the other radeon drivers
LIBDRM_REQUIRED_RADEON='[>=2.4.71]'
# The below version is needed to build dri or gallium nouveau
LIBDRM_REQUIRED_NOUVEAU='[>=2.4.66]'
# The below version is needed to build dri or gallium i915
LIBDRM_REQUIRED_INTEL='[>=2.4.75]'
# NOTE(Cogitri): for xcb-glx
XCBDRI2_REQUIRED='[>=1.8.1]'

# TODO state trackers: OpenMAX(omx), requires additional new dependency libomxil-bellagio
DEPENDENCIES="
    build:
        dev-lang/python:2.7
        dev-libs/libpthread-stubs[>=0.4]
        dev-python/Mako[>=0.8.0][python_abis:2.7]
        sys-devel/bison
        sys-devel/flex
        virtual/pkg-config[>=0.9.0]
        !x11-dri/eclectic-opengl
        gl-vendor? ( dev-libs/libglvnd[>=0.2.0] )
        opencl? ( dev-lang/clang[>=3.9] )
        X? ( x11-proto/xorgproto )
    build+run:
        dev-libs/expat
        sys-libs/zlib[>=1.2.3]
        x11-dri/libdrm${LIBDRM_REQUIRED}
        llvm? ( dev-lang/llvm[>=3.9.0][-static(-)] [[
                note = [ meson build system doesn't support static llvm ]
            ]]
        )
        sensors? (
            sys-apps/lm_sensors[>=3.4.0]
        )
        opencl? (
            dev-lang/llvm[>=3.9.0][-static(-)]
            dev-libs/libclc
        )
        va? (
            x11-libs/libX11
            x11-libs/libva[>=1.6.0]
            x11-libs/libxcb${XCBDRI2_REQUIRED}
        )
        valgrind? ( dev-util/valgrind )
        vdpau? (
            x11-libs/libX11
            x11-libs/libvdpau[>=1.1]
            x11-libs/libxcb${XCBDRI2_REQUIRED}
        )
        video_drivers:i915? ( x11-dri/libdrm${LIBDRM_REQUIRED_INTEL}[video_drivers:intel(+)] )
        video_drivers:intel? ( x11-dri/libdrm${LIBDRM_REQUIRED_INTEL}[video_drivers:intel(+)] )
        video_drivers:nouveau? ( x11-dri/libdrm${LIBDRM_REQUIRED_NOUVEAU}[video_drivers:nouveau(-)] )
        video_drivers:nouveau-legacy? ( x11-dri/libdrm${LIBDRM_REQUIRED_NOUVEAU}[video_drivers:nouveau(-)] )
        video_drivers:r300? ( x11-dri/libdrm${LIBDRM_REQUIRED_RADEON}[video_drivers:radeon(-)] )
        video_drivers:radeon? (
            dev-lang/llvm[>=4.0.0][-static(-)]
            dev-util/elfutils
            x11-dri/libdrm${LIBDRM_REQUIRED_AMDGPU}[video_drivers:radeon(-)]
        )
        video_drivers:radeon-legacy? ( x11-dri/libdrm${LIBDRM_REQUIRED_RADEON}[video_drivers:radeon(-)] )
        video_drivers:vc4? ( x11-dri/libdrm[video_drivers:vc4(-)] )
        video_drivers:vmware? ( x11-dri/libdrm[video_drivers:vmware(-)] )
        wayland? (
            sys-libs/wayland[>=1.11]
            sys-libs/wayland-protocols[>=1.8.0]
        )
        X? (
            x11-libs/libICE
            x11-libs/libX11[xcb(+)]
            x11-libs/libXau
            x11-libs/libxcb
            x11-libs/libXdamage[>=1.1]
            x11-libs/libXdmcp
            x11-libs/libXext
            x11-libs/libXfixes
            x11-libs/libxshmfence[>=1.1]
            x11-libs/libXxf86vm
        )
        xvmc? (
            x11-libs/libX11
            x11-libs/libXvMC[>=1.0.6]
            x11-libs/libxcb${XCBDRI2_REQUIRED}
        )
        !sys-libs/wayland[<1.15.0] [[
            description = [ wayland imported libwayland-egl from mesa ]
            resolution = uninstall-blocked-after
        ]]
    run:
        opencl? (
            dev-libs/ocl-icd
        )
        !media-libs/libtxc_dxtn [[
                description = [ mesa now bundles libtxc_dxtn ]
                resolution = uninstall-blocked-after
        ]]
    suggestion:
        x11-dri/mesa-demos [[
            description = [ Provides useful programs like glxinfo ]
        ]]
"

mesa-meson_src_prepare() {
    # Meson's meson build system requires pkg-config to do some
    # fancy, custom stuff, which use pkg-config directly.
    edo mkdir "${WORKBASE}"/bin
    edo ln -s "/usr/$(exhost --build)/bin/${PKG_CONFIG}" "${WORKBASE}"/bin/pkg-config
    export PATH="${WORKBASE}/bin:${PATH}"

    meson_src_prepare
}

mesa-meson_src_configure() {
    DRI_DRIVERS=( )
    EGL_PLATFORMS=( )
    GALLIUM_DRIVERS=( )
    VULKAN_DRIVERS=( )

    option !video_drivers:gallium-swrast    && DRI_DRIVERS+=( swrast )
    option video_drivers:intel              && DRI_DRIVERS+=( i915 i965 )
    option video_drivers:nouveau-legacy     && DRI_DRIVERS+=( nouveau )
    option video_drivers:radeon-legacy      && DRI_DRIVERS+=( r100 r200 )

    # TODO: pl111,freedeno,softpipe,vc4,etnaviv,imx,svga,swr
    option video_drivers:gallium-swrast     && GALLIUM_DRIVERS+=( swrast )
    option video_drivers:i915               && GALLIUM_DRIVERS+=( i915 )
    option video_drivers:nouveau            && GALLIUM_DRIVERS+=( nouveau )
    option video_drivers:r300               && GALLIUM_DRIVERS+=( r300 )
    option video_drivers:radeon             && GALLIUM_DRIVERS+=( r600 radeonsi )
    option video_drivers:vc4                && GALLIUM_DRIVERS+=( vc4 )
    option video_drivers:virtio-gpu         && GALLIUM_DRIVERS+=( virgl )
    option video_drivers:vmware             && GALLIUM_DRIVERS+=( svga )

    option X                                && EGL_PLATFORMS+=( x11 )
    option wayland                          && EGL_PLATFORMS+=( wayland )
                                               EGL_PLATFORMS+=( drm surfaceless )

    option video_drivers:intel              && VULKAN_DRIVERS+=( intel )
    option video_drivers:radeon             && VULKAN_DRIVERS+=( amd )

    local MESA_SRC_CONFIGURE_PARAMS

    MESA_SRC_CONFIGURE_PARAMS+=(
        -Dasm=true
        -Ddri-drivers="$(IFS=, ; echo "${DRI_DRIVERS[*]}")"
        -Degl=true
        -Dgallium-drivers=$(IFS=, ; echo "${GALLIUM_DRIVERS[*]}")
        -Dgles1=true
        -Dgles2=true
        -Dlibunwind=false
        -Dopengl=true
        -Dshared-glapi=true
        -Dplatforms=$(IFS=, ; echo "${EGL_PLATFORMS[*]}")
        -Dshader-cache=true
        -Dvulkan-drivers=$(IFS=, ; echo "${VULKAN_DRIVERS[*]}")

        # OSMesa needs either gallium_softpipe (GALLIUM_DRIVERS=swrast) or dri swrast
        # (DRI_DRIVERS=SWRAST) to be enabled.
        $(meson_switch video_drivers:gallium-swrast osmesa gallium classic)

        $(meson_switch d3d9 gallium-nine)
        $(meson_switch gl-vendor glvnd)
        $(meson_switch llvm)
        $(meson_switch opencl gallium-opencl icd disabled)
        $(meson_switch sensors lmsensors)
        $(meson_switch sensors gallium-extra-hud)
        $(meson_switch texture-float)
        $(meson_switch va gallium-va)
        $(meson_switch valgrind)
        $(meson_switch vdpau gallium-vdpau)
        $(meson_switch X dri3)
        $(meson_switch X glx dri disabled)
        $(meson_switch xa gallium-xa)
        $(meson_switch xvmc gallium-xvmc)
    )

    # Missing dependency
    if ever at_least 18.1; then
        MESA_SRC_CONFIGURE_PARAMS+=(
            -Dgallium-omx=disabled
        )
    else
        MESA_SRC_CONFIGURE_PARAMS+=(
            -Dgallium-omx=false
        )
    fi

    exmeson "${MESA_SRC_CONFIGURE_PARAMS[@]}" "${MESON_SOURCE}"
}

mesa-meson_src_install() {
    dodir /usr

    local host=$(exhost --target)
    local X_alternatives=()

    meson_src_install

    # alternatives
    local libs=(libEGL libGLESv1_CM libGLESv2)
    option X && libs+=(libGL)

    edo mkdir "${IMAGE}"/usr/${host}/lib/opengl/

    local lib path_old path_new soname
    for lib in "${libs[@]}"; do
        path_new=/usr/${host}/lib/opengl/${lib}-xorg.so
        path_old=$(readlink -f "${IMAGE}"/usr/${host}/lib/${lib}.so)

        edo mv \
            "${path_old}" \
            "${IMAGE}"/${path_new}

        local objdump=$(exhost --tool-prefix)objdump
        soname=$(edo ${objdump} -p "${IMAGE}"/${path_new} | sed -n 's/^ *SONAME *//p')

        # clean up the leftover symlinks
        edo rm "${IMAGE}"/usr/${host}/lib/{${lib}.so,${soname}}

        X_alternatives+=(
            /usr/${host}/lib/${lib}.so ${path_new}
            /usr/${host}/lib/${soname} ${path_new}
        )
    done

    if option wayland ; then
        # wayland[>=1.15] imported libwayland-egl in order to allow multiple
        # drivers using it.
        edo rm "${IMAGE}"/usr/$(exhost --target)/lib/pkgconfig/wayland-egl.pc \
               "${IMAGE}"/usr/$(exhost --target)/lib/libwayland-egl.so*
    fi

    alternatives_for opengl X.org 10 ${X_alternatives[@]}

    edo rm -rf "${IMAGE}"/usr/${host}/include/GL/{glew,glxew,wglew}.h
}