#!/bin/sh
# pdecc — one-shot Processing-to-Raylib compiler CLI.
#
# Transpile + compile a .pde sketch into an optimized native binary in one
# step, using the pde2c transpiler and the processing.h single-header runtime.
# Submitted as a single source file or a sketch directory (multi-tab), the
# resulting binary is written next to the sketch source by default.
#
#   ./pdecc                       sketch in current directory
#   ./pdecc sketch.pde            single-file sketch
#   ./pdecc ~/path/to/sketch      sketch directory (all .pde tabs together)
#   ./pdecc -o bin sketch.pde     write binary to "bin" instead
#   ./pdecc -O0 sketch.pde        override default -O2 optimization
#   ./pdecc -n sketch.pde         build only (do not run)
#   ./pdecc --keep sketch.pde     keep the tmp build dir
#
# Exit status: 0 on success, non-zero on transpile/compile failure.
set -u

SCRIPT_DIR=$(dirname "$(readlink -f "$0")")

OPT="2"           # default optimization level (no leading 'O')
OUT=""            # explicit -o output path (default: next to source)
RUN=1             # run after building unless -n
KEEP=0            # keep tmp dir when --keep

# ---- argument parsing -----------------------------------------------------
TARGET=""
while [ $# -gt 0 ]; do
  case "$1" in
    -o) shift; [ $# -eq 0 ] && { echo "pdecc: -o needs a path" >&2; exit 1; }
        OUT="$1";;
    -O|-O0|-O1|-O2|-O3|-Os) OPT="${1#-O}";;
    -n|--no-run) RUN=0;;
    --keep) KEEP=1;;
    -h|--help)
        sed -n '2,16p' "$0"; exit 0;;
    -*) echo "pdecc: unknown option: $1" >&2; exit 1;;
    *)  [ -n "$TARGET" ] && { echo "pdecc: too many arguments: $1" >&2; exit 1; }
        TARGET="$1";;
  esac
  shift
done

# ---- resolve target: dir, .pde file, or current dir -----------------------
if [ -z "$TARGET" ]; then
  TARGET=$(pwd)
fi
TARGET=$(realpath "$TARGET")

if [ -d "$TARGET" ]; then
  SKETCH_DIR="$TARGET"
  MAIN_PDE="$SKETCH_DIR/$(basename "$SKETCH_DIR").pde"
  if [ ! -f "$MAIN_PDE" ]; then
    echo "pdecc: expected main tab $MAIN_PDE (folder name must match the main .pde)" >&2
    exit 1
  fi
  BNAME=$(basename "$SKETCH_DIR")
elif [ -f "$TARGET" ] && [ "${TARGET##*.}" = "pde" ]; then
  MAIN_PDE="$TARGET"
  SKETCH_DIR=$(dirname "$MAIN_PDE")
  BNAME=$(basename "$MAIN_PDE" .pde)
else
  echo "pdecc: invalid target: $TARGET (expected a .pde file or a sketch directory)" >&2
  exit 1
fi

OUT="${OUT:-$SKETCH_DIR/$BNAME}"

# ---- build dir -------------------------------------------------------------
TMP=$(mktemp -d /tmp/pdecc.XXXXXX)
cleanup() { [ "$KEEP" = "1" ] || rm -rf "$TMP"; }
trap cleanup EXIT INT TERM

# rebuild transpiler only when its source changed
if [ "$SCRIPT_DIR/pde2c.c" -nt "$SCRIPT_DIR/pde2c" ] || [ ! -x "$SCRIPT_DIR/pde2c" ]; then
  gcc "$SCRIPT_DIR/pde2c.c" -o "$SCRIPT_DIR/pde2c" || exit 1
fi

# rebuild precompiled header only when processing.h got newer; skip re-parsing
# raylib/rlgl/raymath on every compile (cuts turnaround from ~3s to ~0.2s).
if [ "$SCRIPT_DIR/processing.h" -nt "$SCRIPT_DIR/processing.h.gch" ] || \
   [ ! -f "$SCRIPT_DIR/processing.h.gch" ]; then
  if ! gcc $("$SCRIPT_DIR/pdedeps" --includes) -x c-header "$SCRIPT_DIR/processing.h" \
       -o "$SCRIPT_DIR/processing.h.gch" 2>/dev/null; then
    rm -f "$SCRIPT_DIR/processing.h.gch"   # stale/broken PCH: fall back to
  fi                                       # slow path (never fatal)
fi

# ---- merge tabs: main tab first, then the rest alphabetically -------------
{
  printf '//@file %s\n' "$(basename "$MAIN_PDE")"
  cat "$MAIN_PDE"
  for f in $(find "$SKETCH_DIR" -maxdepth 1 -name '*.pde' | sort); do
    [ "$f" = "$MAIN_PDE" ] && continue
    printf '//@file %s\n' "$(basename "$f")"
    cat "$f"
  done
} > "$TMP/combined.pde"

if ! grep -q '[^[:space:]]' "$TMP/combined.pde"; then
  echo "pdecc: no .pde content found in $SKETCH_DIR" >&2
  exit 1
fi

# copy runtime resources so font loading resolves from the build dir
cp "$SCRIPT_DIR/terminus.ttf" "$TMP/terminus.ttf" 2>/dev/null || true

# ---- transpile -------------------------------------------------------------
if ! "$SCRIPT_DIR/pde2c" "$TMP/combined.pde" > "$TMP/sketch.c" 2> "$TMP/pde2c.err"; then
  echo "pdecc: transpile failed for $BNAME" >&2
  cat "$TMP/pde2c.err" >&2
  exit 1
fi

# ---- compile to an optimized native binary ---------------------------------
if ! gcc -O"$OPT" $("$SCRIPT_DIR/pdedeps" --includes) "$TMP/sketch.c" -o "$OUT" \
     $("$SCRIPT_DIR/pdedeps" --libs) 2> "$TMP/gcc.err"; then
  echo "pdecc: compilation failed for $BNAME" >&2
  head -20 "$TMP/gcc.err" >&2
  if [ "$KEEP" = "1" ]; then
    echo "pdecc: kept build dir $TMP (set --keep or PDE_KEEP=1 to inspect)" >&2
  fi
  exit 1
fi

echo "pdecc: built $OUT"
[ "$RUN" = "1" ] && (cd "$SKETCH_DIR" && exec "$OUT")
exit 0