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

# Build gplan.so for the Onefinity Pi (armv7l, Python 3.5)
#
# First run:   ~30min (builds the Docker image with pre-compiled cbang/camotics)
# After that:  ~2sec  (just relinks against Python 3.5m)
#
# Prerequisites:
#   - Docker with QEMU binfmt support (default on Docker Desktop)
#   - Python 3.5 headers from the Pi in .pi/pi-python35.tar.gz
#     Grab once: ssh bbmc@10.1.10.55 'tar czf - /usr/include/python3.5m \
#       /usr/lib/arm-linux-gnueabihf/libpython3.5m.so*' > .pi/pi-python35.tar.gz

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
IMAGE="onefin-gplan"
HEADERS="$SCRIPT_DIR/pi-python35.tar.gz"
OUTPUT="$PROJECT_DIR/src/py/camotics/gplan.so"

# Check for Python 3.5 headers
if [[ ! -f "$HEADERS" ]]; then
    echo "Python 3.5 headers not found at $HEADERS"
    echo "Fetching from Pi..."
    ssh bbmc@10.1.10.55 'tar czf - /usr/include/python3.5m \
      /usr/lib/arm-linux-gnueabihf/libpython3.5m.so*' > "$HEADERS"
fi

# Build image if needed (one-time, ~30min)
if ! docker image inspect "$IMAGE" >/dev/null 2>&1; then
    echo "Building $IMAGE Docker image (one-time, ~30min under QEMU)..."
    docker build --platform linux/arm/v7 -t "$IMAGE" -f "$SCRIPT_DIR/Dockerfile.gplan" "$SCRIPT_DIR"
fi

# Relink gplan.so against Python 3.5m (~2sec)
echo "Linking gplan.so against Python 3.5m..."
docker run --rm --platform linux/arm/v7 \
    -v "$HEADERS:/tmp/pi-python35.tar.gz:ro" \
    -v "$PROJECT_DIR:/workspace" \
    "$IMAGE" bash -c '
    tar xzf /tmp/pi-python35.tar.gz -C /
    ln -sf /usr/lib/arm-linux-gnueabihf/libpython3.5m.so.1.0 \
           /usr/lib/arm-linux-gnueabihf/libpython3.5m.so

    g++ -o /workspace/src/py/camotics/gplan.so \
      -Wl,--as-needed -Wl,-s -Wl,-x -Wl,--gc-sections -pthread -shared \
      build/gplan.os -L/opt/cbang/lib \
      build/libCAMoticsPy.a build/libCAMotics.a build/libDXF.a \
      build/libSTL.a build/libGCode.a \
      -lstdc++ -lutil -lm -ldl -lz -lcbang -lcbang-boost \
      -lssl -lcrypto -llz4 -lexpat -lbz2 -lcrypt -lpthread \
      -lpython3.5m build/dxflib/libdxflib.a

    file /workspace/src/py/camotics/gplan.so
    readelf -d /workspace/src/py/camotics/gplan.so | grep python
'

echo "✓ Built: $OUTPUT"