#!/usr/bin/env bash
# Bring up the headless display, then hand over to the command.
#
# Xvfb and openbox are started HERE, as children of PID 1 (tini), rather than by
# the toolkit scripts. That is the fix for the long-standing "Xvfb and the
# emulator die on their own every few minutes" note: nothing owned those
# processes, so nothing kept them alive, and a run could sit for 300 s in front
# of a visible MAIN MENU reporting "no main menu" because the display had gone.
# A container-lifetime display makes that failure mode impossible.
set -euo pipefail

log() { printf '[entrypoint] %s\n' "$*" >&2; }

DISPLAY="${DISPLAY:-:98}"
GEOM="${SCREEN_GEOMETRY:-1280x720x24}"
export DISPLAY

# ── Display ──────────────────────────────────────────────────────────────────
if ! xdpyinfo -display "$DISPLAY" >/dev/null 2>&1; then
  rm -f "/tmp/.X${DISPLAY#:}-lock" "/tmp/.X11-unix/X${DISPLAY#:}" 2>/dev/null || true
  # GLX and RANDR are both required: Canary's window is GTK+OpenGL even when the
  # graphics backend is Vulkan, and xwininfo-based screen oracles need RANDR.
  Xvfb "$DISPLAY" -screen 0 "$GEOM" -ac -nolisten tcp \
       +extension GLX +extension RANDR >/tmp/xvfb.log 2>&1 &
  for _ in $(seq 1 50); do
    xdpyinfo -display "$DISPLAY" >/dev/null 2>&1 && break
    sleep 0.2
  done
fi
if ! xdpyinfo -display "$DISPLAY" >/dev/null 2>&1; then
  log "FATAL: no display on $DISPLAY — see /tmp/xvfb.log"
  exit 1
fi

# A window manager is not cosmetic here: without one the emulator window is
# never mapped at a known position, and every pixel oracle reads the wrong rows.
if ! pgrep -x openbox >/dev/null 2>&1; then
  openbox >/tmp/openbox.log 2>&1 &
  sleep 0.5
fi
log "display $DISPLAY ready ($GEOM)"

# ── Vulkan ───────────────────────────────────────────────────────────────────
# Prefer the real GPU when /dev/dri was passed through; fall back to lavapipe,
# which is slow but correct and needs no host device.
LVP=$(ls /usr/share/vulkan/icd.d/lvp_icd*.json 2>/dev/null | head -1)
if [ "${SYLPH_VULKAN:-auto}" = "sw" ] || [ ! -e /dev/dri/renderD128 ]; then
  [ -n "$LVP" ] && export VK_ICD_FILENAMES="$LVP"
else
  unset LIBGL_ALWAYS_SOFTWARE
fi
# Report what Vulkan ACTUALLY enumerated, not what we asked for. Announcing
# "host GPU via /dev/dri" because the device node exists is how an agent ends up
# believing it has hardware while running llvmpipe — an NVIDIA card needs the
# NVIDIA Container Toolkit, and /dev/dri alone does nothing for it.
if command -v vulkaninfo >/dev/null 2>&1; then
  vkdev=$(vulkaninfo --summary 2>/dev/null | awk -F= '/deviceName/{gsub(/^ +| +$/,"",$2); print $2; exit}')
  case "${vkdev:-}" in
    "")            log "Vulkan: NO DEVICE — vulkaninfo enumerated nothing" ;;
    llvmpipe*|lavapipe*) log "Vulkan: $vkdev (SOFTWARE — correct but slow)" ;;
    *)             log "Vulkan: $vkdev (hardware)" ;;
  esac
fi

# ── Build parallelism ────────────────────────────────────────────────────────
# Bounded by MEMORY, not just cores. A full-parallel build of this tree has
# OOM-killed the host outright, and inside a half-the-box container the ceiling
# is lower still. ~1.5 GiB per C++ TU is the rule of thumb that has held.
# nproc reports the HOST's core count: --cpus is a CFS quota, not a mask. Using
# it would oversubscribe a half-the-box container by exactly 2x, so read the
# quota the cgroup actually grants.
cpus=$(nproc)
if [ -r /sys/fs/cgroup/cpu.max ]; then
  read -r _q _p < /sys/fs/cgroup/cpu.max || true
  if [ "${_q:-max}" != max ] && [ "${_p:-0}" -gt 0 ]; then
    cpus=$(( (_q + _p - 1) / _p ))
    [ "$cpus" -lt 1 ] && cpus=1
  fi
fi
mem_gib=$(awk '/MemAvailable/{printf "%d", $2/1048576}' /proc/meminfo)
# MemAvailable is the HOST's too under cgroup v2; prefer the container's cap.
if [ -r /sys/fs/cgroup/memory.max ]; then
  _m=$(cat /sys/fs/cgroup/memory.max)
  [ "$_m" != max ] && mem_gib=$(( _m / 1073741824 ))
fi
[ "${mem_gib:-0}" -lt 1 ] && mem_gib=1
by_mem=$(( mem_gib * 2 / 3 ))
[ "$by_mem" -lt 1 ] && by_mem=1
jobs=$(( cpus < by_mem ? cpus : by_mem ))
export SYLPH_JOBS="$jobs" CARGO_BUILD_JOBS="$jobs" CMAKE_BUILD_PARALLEL_LEVEL="$jobs"
log "build parallelism: $jobs (cpus=$cpus, mem=${mem_gib}GiB avail)"

mkdir -p "$HOME/shots" "$HOME/logs"

# ── Claude Code ──────────────────────────────────────────────────────────────
if [ "${SYLPH_AUTONOMOUS:-0}" = "1" ]; then
  # The flag the user asked for. It is refused under root, which is why this
  # image runs as `agent`.
  set -- claude --dangerously-skip-permissions "$@"
  log "starting Claude Code with --dangerously-skip-permissions"
fi

exec "$@"