# Maintainer: Markus Fritsche <mfritsche@reauktion.de>
#
# Chromium with V4L2 HW video decode unlocked on Linux for Rockchip
# (RK3566 hantro / RK3588 VDPU381) on **mainline** kernel + Wayland +
# panfrost / panthor — no vendor MPP, no Mali blob, no panfork, no
# 5.10 BSP kernel. Fills the niche that 7Ji's chromium-mpp explicitly
# does not (it forces BSP + X11 + vendor stack); see STUDY.md and
# NEXT.md alongside this PKGBUILD for the full rationale and the
# validation log on PineTab2 (RK3566).
#
# Multi-arch: builds natively on x86_64 and aarch64. The x86_64 path
# is primarily a development / CI host; the runtime target audience is
# aarch64. The two patches are architecture-independent.

pkgname=chromium-fourier
pkgver=147.0.7727.116
pkgrel=2
epoch=1
pkgdesc='Chromium with V4L2VDA HW video decode unlocked for mainline Linux Wayland on Rockchip'
arch=('aarch64' 'x86_64')
url='https://www.chromium.org/Home'
license=('BSD-3-Clause')
depends=(
  alsa-lib
  at-spi2-core
  cairo
  cups
  dbus
  fontconfig
  freetype2
  gtk3
  hicolor-icon-theme
  libdrm
  libpulse
  libva
  libxcb
  libxkbcommon
  mesa
  nspr
  nss
  pango
  pciutils
  pipewire
  ttf-liberation
  v4l-utils
  wayland
)
makedepends=(
  clang
  elfutils
  gn
  gperf
  java-runtime-headless
  libxslt
  lld
  ninja
  nodejs
  npm
  python
  qt5-base
  qt6-base
  re2
  rust
  rust-bindgen
)
optdepends=(
  'qt6-base: for Qt6 toolkit integration'
)
provides=(chromium)
conflicts=(chromium)
options=('!lto' '!strip')

# Canonical chromium release tarball (5.7 GB compressed). Versions track
# the chromium release schedule (see https://chromiumdash.appspot.com).
# When bumping pkgver the patches may need their hunk line numbers
# refreshed against the new tree — they are written against
# media/base/media_switches.cc and ui/ozone/platform/wayland/gpu/wayland_surface_factory.cc
# which both move around between minor releases.
source=(
  "https://commondatastorage.googleapis.com/chromium-browser-official/chromium-${pkgver}.tar.xz"
  'patches/enable-v4l2-decoder-default.patch'
  'patches/wayland-allow-direct-egl-gles2.patch'
  'patches/nv12-external-oes-on-modifier-external-only.patch'
)
sha256sums=(
  'SKIP'
  'SKIP'
  'SKIP'
  'SKIP'
)

prepare() {
  cd "${srcdir}/chromium-${pkgver}"

  # Fourier patch 1/2: flip kAcceleratedVideoDecodeLinux's default to
  # enabled when USE_V4L2_CODEC is the build's HW decode path. Without
  # this the runtime master gate stays off on USE_V4L2_CODEC-only builds
  # and chrome silently falls back to ffmpeg software decode. See the
  # patch header for the validation log on RK3566 hantro.
  patch -Np1 -i "${srcdir}/patches/enable-v4l2-decoder-default.patch"

  # Fourier patch 2/3: re-allow the direct EGL/GLES2 path in the Wayland
  # ozone surface factory so panfrost's EGL_EXT_image_dma_buf_import
  # surfaces to chrome's GL display, lighting up the NV12 zero-copy
  # native-pixmap pipeline. The launcher defaults to ANGLE (DCHECK in
  # gl_context_egl.cc:241 fires on direct EGL with non-official builds);
  # this patch keeps the direct path available for users who flip
  # is_official_build=true and want the lower-CPU pipeline.
  patch -Np1 -i "${srcdir}/patches/wayland-allow-direct-egl-gles2.patch"

  # Fourier patch 3/3: pick GL_TEXTURE_EXTERNAL_OES for NV12 dmabufs
  # whose DRM modifier is advertised external_only by the EGL driver.
  # On panfrost / panthor every NV12 modifier (LINEAR + AFBC + AFRC) is
  # external_only; chromium's default OzoneImageGLTexturesHolder picked
  # GL_TEXTURE_2D and ANGLE then rejected the YUV EGLImage on a
  # non-EXTERNAL_OES target, forcing the NV12->AR24 software conversion
  # fallback. This closes that gap and enables the actual zero-copy
  # path. Validated on ohm (RK3566 hantro): 1080p30 H.264 drops from
  # ~131% combined CPU to ~34.7% (~3.8x). See patches/0004 for context.
  patch -Np1 -i "${srcdir}/patches/nv12-external-oes-on-modifier-external-only.patch"

  # Use system node, system java
  case "$CARCH" in
    aarch64) _node_dir=node-linux-arm64 ;;
    x86_64)  _node_dir=node-linux-x64 ;;
  esac
  rm -f "third_party/node/linux/${_node_dir}/bin/node"
  mkdir -p "third_party/node/linux/${_node_dir}/bin"
  ln -sf /usr/bin/node "third_party/node/linux/${_node_dir}/bin/"
  ln -sf /usr/bin/java third_party/jdk/current/bin/ 2>/dev/null || true
}

build() {
  cd "${srcdir}/chromium-${pkgver}"

  case "$CARCH" in
    aarch64) _target_cpu="arm64" ;;
    x86_64)  _target_cpu="x64"   ;;
  esac

  local _flags=(
    "target_cpu=\"${_target_cpu}\""

    'is_official_build=false'
    'is_debug=false'
    # dcheck_always_on defaults to !is_official_build (true here);
    # explicitly off so the direct EGL/GLES2 path doesn't FATAL on
    # gl_context_egl.cc:241's DCHECK(!global_texture_share_group_).
    'dcheck_always_on=false'
    'symbol_level=0'
    'is_cfi=false'
    'treat_warnings_as_errors=false'
    'enable_nacl=false'
    'enable_widevine=false'

    # System toolchain (clang/lld from pacman)
    'custom_toolchain="//build/toolchain/linux/unbundle:default"'
    'host_toolchain="//build/toolchain/linux/unbundle:default"'
    'use_sysroot=false'
    'use_custom_libcxx=true'

    # The whole point of chromium-fourier — V4L2 HW decode on Linux
    'use_v4l2_codec=true'
    'use_v4lplugin=true'
    'use_linux_v4l2_only=true'
    'use_vaapi=false'

    # Codec branding for proprietary codec support (H.264 etc.)
    'ffmpeg_branding="Chrome"'
    'proprietary_codecs=true'

    'rtc_use_pipewire=true'
    'link_pulseaudio=true'
    'use_qt6=true'
    'moc_qt6_path="/usr/lib/qt6"'
  )

  gn gen out/Default --args="${_flags[*]}"
  ninja -C out/Default chrome chrome_crashpad_handler
}

package() {
  cd "${srcdir}/chromium-${pkgver}"

  install -Dm755 out/Default/chrome "${pkgdir}/usr/lib/chromium/chromium"
  install -Dm755 out/Default/chrome_crashpad_handler \
    "${pkgdir}/usr/lib/chromium/chrome_crashpad_handler"
  [ -f out/Default/chrome_sandbox ] && install -Dm4755 out/Default/chrome_sandbox \
    "${pkgdir}/usr/lib/chromium/chrome-sandbox"
  [ -f out/Default/chromedriver ] && install -Dm755 out/Default/chromedriver \
    "${pkgdir}/usr/bin/chromedriver"

  # Bundled GL/Vulkan runtime — chrome dlopens these from its own dir,
  # not /usr/lib/. Without them GL init fails and chrome falls back to
  # software compositing.
  for so in libEGL.so libGLESv2.so libvk_swiftshader.so libvulkan.so.1; do
    [ -f "out/Default/$so" ] && install -Dm755 "out/Default/$so" \
      "${pkgdir}/usr/lib/chromium/$so"
  done
  # ANGLE and SwiftShader ICD config files
  for icd in out/Default/*_icd.json; do
    [ -f "$icd" ] && install -Dm644 "$icd" \
      "${pkgdir}/usr/lib/chromium/$(basename "$icd")"
  done

  # Resources / locales / pak files
  for f in chrome_100_percent.pak chrome_200_percent.pak resources.pak \
           v8_context_snapshot.bin snapshot_blob.bin icudtl.dat \
           headless_lib_data.pak headless_lib_strings.pak \
           headless_command_resources.pak; do
    [ -f "out/Default/$f" ] && install -Dm644 "out/Default/$f" \
      "${pkgdir}/usr/lib/chromium/$f"
  done

  # Locales
  if [ -d out/Default/locales ]; then
    install -dm755 "${pkgdir}/usr/lib/chromium/locales"
    cp -r out/Default/locales/* "${pkgdir}/usr/lib/chromium/locales/"
  fi

  # Launcher shim — defaults to ANGLE→GLES on Wayland with Vulkan
  # disabled. Vulkan is off by default because:
  #   - panvk on RK3566 (Mali-G52 Bifrost) returns
  #     VK_ERROR_INCOMPATIBLE_DRIVER on chromium's probe and breaks
  #     V4L2 dispatch downstream (chrome falls back to FFmpeg software);
  #   - panthor on RK3588 (Mali-G610 Valhall) is more functional but
  #     not yet validated end-to-end against this build.
  #
  # User overrides for development on other Rockchips:
  #   --enable-features=Vulkan         enable Vulkan (panthor / others)
  #   --use-vulkan=native|swiftshader  pick the Vulkan backend
  #   --disable-features=Vulkan        explicit re-disable
  # Any of those on the command line short-circuits the launcher's
  # default disable, so the user's intent always wins.
  install -dm755 "${pkgdir}/usr/bin"
  cat > "${pkgdir}/usr/bin/chromium" <<'LAUNCHER'
#!/bin/bash
# chromium-fourier launcher — V4L2 HW decode + Wayland + ANGLE
# Vulkan disabled by default; pass --enable-features=Vulkan or
# --use-vulkan=native to opt in (e.g. RK3588 panthor work).

USER_HANDLES_VULKAN=0
for arg in "$@"; do
  case "$arg" in
    --use-vulkan*|--enable-features=*Vulkan*|--disable-features=*Vulkan*|--use-angle=vulkan*)
      USER_HANDLES_VULKAN=1
      break
      ;;
  esac
done

vulkan_default=()
if [ "$USER_HANDLES_VULKAN" = 0 ]; then
  vulkan_default=(--disable-features=Vulkan)
fi

exec /usr/lib/chromium/chromium \
  --ozone-platform=wayland \
  --use-gl=angle --use-angle=gles \
  --enable-features=AcceleratedVideoDecoder \
  "${vulkan_default[@]}" \
  "$@"
LAUNCHER
  chmod 0755 "${pkgdir}/usr/bin/chromium"
}