#!/usr/bin/env bash
set -euo pipefail

usage() {
  cat <<'EOF'
Usage:
  mangohud-position-lab.sh <config> [app] [output_dir]

Examples:
  mangohud-position-lab.sh ~/.config/mangotune/profiles/zz_test_right_sparse_top.conf glxgears
  mangohud-position-lab.sh ~/.config/mangotune/profiles/zz_test_right_full_top.conf vkcube /tmp/mh-lab

Notes:
  - This runs MangoHud directly, outside MangoTune's preview pipeline.
  - OpenGL uses MANGOHUD_DLSYM=1.
  - If xdotool/import are installed and a real X11 session is available, a screenshot
    and basic window geometry will be written to the output directory.
  - Override DISPLAY/XAUTHORITY/WAIT_SECS/WIDTH/HEIGHT from the environment when needed.
EOF
}

if [[ "${1:-}" == "-h" || "${1:-}" == "--help" || $# -lt 1 ]]; then
  usage
  exit 0
fi

CONFIG_PATH="$1"
APP="${2:-glxgears}"
OUTPUT_DIR="${3:-/tmp/mangohud-position-lab}"
DISPLAY_VALUE="${DISPLAY:-:0}"
XAUTH_VALUE="${XAUTHORITY:-$HOME/.Xauthority}"
WAIT_SECS="${WAIT_SECS:-4}"
WIDTH="${WIDTH:-1400}"
HEIGHT="${HEIGHT:-760}"

mkdir -p "$OUTPUT_DIR"
rm -f "$OUTPUT_DIR"/run.log "$OUTPUT_DIR"/window.geom "$OUTPUT_DIR"/window.png \
  "$OUTPUT_DIR"/screen.png "$OUTPUT_DIR"/window_from_screen.png

if [[ ! -f "$CONFIG_PATH" ]]; then
  echo "Config not found: $CONFIG_PATH" >&2
  exit 2
fi

cleanup() {
  if [[ -n "${PID:-}" ]]; then
    kill "$PID" 2>/dev/null || true
    wait "$PID" 2>/dev/null || true
  fi
}

trap cleanup EXIT

case "$APP" in
  glxgears)
    MATCH_NAME="glxgears"
    DISPLAY="$DISPLAY_VALUE" \
    XAUTHORITY="$XAUTH_VALUE" \
    MANGOHUD_CONFIGFILE="$CONFIG_PATH" \
    MANGOHUD_DLSYM=1 \
    mangohud glxgears -geometry "${WIDTH}x${HEIGHT}" >"$OUTPUT_DIR/run.log" 2>&1 &
    ;;
  vkcube)
    MATCH_NAME="Vkcube"
    DISPLAY="$DISPLAY_VALUE" \
    XAUTHORITY="$XAUTH_VALUE" \
    MANGOHUD_CONFIGFILE="$CONFIG_PATH" \
    WGPU_BACKEND="${WGPU_BACKEND:-gl}" \
    mangohud vkcube --width "$WIDTH" --height "$HEIGHT" >"$OUTPUT_DIR/run.log" 2>&1 &
    ;;
  *)
    echo "Unsupported app: $APP" >&2
    exit 2
    ;;
esac

PID=$!
echo "pid=$PID" >>"$OUTPUT_DIR/run.log"
printf 'display=%s\nxauthority=%s\nwidth=%s\nheight=%s\n' \
  "$DISPLAY_VALUE" "$XAUTH_VALUE" "$WIDTH" "$HEIGHT" >>"$OUTPUT_DIR/run.log"
sleep "$WAIT_SECS"

if command -v xwininfo >/dev/null 2>&1; then
  DISPLAY="$DISPLAY_VALUE" XAUTHORITY="$XAUTH_VALUE" \
    xwininfo -root -tree >"$OUTPUT_DIR/xwininfo.tree" 2>/dev/null || true
fi

if command -v xdotool >/dev/null 2>&1; then
  WINDOW_ID="$(DISPLAY="$DISPLAY_VALUE" XAUTHORITY="$XAUTH_VALUE" xdotool search --name "$MATCH_NAME" 2>/dev/null | tail -n1 || true)"
else
  WINDOW_ID=""
fi

if [[ -n "$WINDOW_ID" ]]; then
  echo "window_id=$WINDOW_ID" >>"$OUTPUT_DIR/run.log"
  DISPLAY="$DISPLAY_VALUE" XAUTHORITY="$XAUTH_VALUE" \
    xdotool getwindowgeometry --shell "$WINDOW_ID" >"$OUTPUT_DIR/window.geom" 2>/dev/null || true
  if command -v import >/dev/null 2>&1; then
    DISPLAY="$DISPLAY_VALUE" XAUTHORITY="$XAUTH_VALUE" \
      import -window "$WINDOW_ID" "$OUTPUT_DIR/window.png" 2>/dev/null || true
    DISPLAY="$DISPLAY_VALUE" XAUTHORITY="$XAUTH_VALUE" \
      import -window root "$OUTPUT_DIR/screen.png" 2>/dev/null || true
    if [[ -f "$OUTPUT_DIR/window.geom" ]] && [[ -f "$OUTPUT_DIR/screen.png" ]] && command -v convert >/dev/null 2>&1; then
      # Crop the full-screen capture back down to the app window bounds. This preserves overlays
      # when the compositor draws them separately from the client window content.
      # shellcheck disable=SC1090
      . "$OUTPUT_DIR/window.geom"
      if [[ -n "${WIDTH:-}" && -n "${HEIGHT:-}" && -n "${X:-}" && -n "${Y:-}" ]]; then
        convert "$OUTPUT_DIR/screen.png" -crop "${WIDTH}x${HEIGHT}+${X}+${Y}" +repage \
          "$OUTPUT_DIR/window_from_screen.png" 2>/dev/null || true
      fi
    fi
  fi
fi

echo "Wrote artifacts to $OUTPUT_DIR"