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

ROOT_DIR="$(cd "$(dirname "$0")/.." && pwd)"
VENDOR_DIR="$ROOT_DIR/vendor/linuxcnc"
BUILD_DIR="$ROOT_DIR/build/native"
WRAP_DIR="$ROOT_DIR/runtime/core/linuxcnc_wrap"
SHIM_DIR="$ROOT_DIR/runtime/core/shims"
INCLUDE_DIR="$ROOT_DIR/runtime/core/include"
MINIMAL_GCODE_FIXTURE="$ROOT_DIR/tests/fixtures/gcode/minimal_linear.ngc"
NAMEDPARAM_INI_FIXTURE="$ROOT_DIR/tests/fixtures/ini/namedparams.ini"
CXX="${CXX:-g++}"

mkdir -p "$BUILD_DIR"

COMMON_FLAGS=(
  -std=c++20
  -O2
  -D_GNU_SOURCE
  -DM_PI=3.14159265358979323846
  -DOBJECT_FWD_DWA2002724_HPP
  -I"$WRAP_DIR"
  -I"$SHIM_DIR"
  -I"$INCLUDE_DIR"
  -I"$VENDOR_DIR/src"
  -I"$VENDOR_DIR/src/rtapi"
  -I"$VENDOR_DIR/src/emc"
  -I"$VENDOR_DIR/src/emc/nml_intf"
  -I"$VENDOR_DIR/src/emc/motion"
  -I"$VENDOR_DIR/src/libnml/posemath"
)

COMMON_INI_FLAGS=(
  "${COMMON_FLAGS[@]}"
  -I"$VENDOR_DIR/src/emc/ini"
)

MINIMAL_FLAGS=(
  "${COMMON_INI_FLAGS[@]}"
  -ffunction-sections
  -fdata-sections
  -DUNIT_TEST
  -DLINUXCNC_STANDALONE_USE_RS274_PRE_STATE
)

MINIMAL_LINK_FLAGS=(
  -Wl,--gc-sections
)

write_command_file() {
  local file="$1"
  shift
  printf '%q\n' "$@" > "$file"
}

command_matches() {
  local file="$1"
  shift

  local tmp
  tmp="$(mktemp)"
  write_command_file "$tmp" "$@"
  if [[ -f "$file" ]] && cmp -s "$tmp" "$file"; then
    rm -f "$tmp"
    return 0
  fi
  rm -f "$tmp"
  return 1
}

depfile_newer_than() {
  local depfile="$1"
  local output="$2"

  [[ -f "$depfile" ]] || return 0
  local deps
  deps="$(tr '\\\n' '  ' < "$depfile" | sed -e 's/^[^:]*://')"
  local dep
  for dep in $deps; do
    if [[ -f "$dep" && "$dep" -nt "$output" ]]; then
      return 0
    fi
  done
  return 1
}

object_needs_rebuild() {
  local obj="$1"
  local depfile="$2"
  local cmdfile="$3"
  shift 3

  [[ -f "$obj" ]] || return 0
  command_matches "$cmdfile" "$@" || return 0
  depfile_newer_than "$depfile" "$obj" && return 0
  return 1
}

compile_object() {
  local target="$1"
  local source="$2"
  local obj="$3"
  shift 3

  local stdout_log="$BUILD_DIR/$target.stdout.log"
  local stderr_log="$BUILD_DIR/$target.stderr.log"
  local depfile="$obj.d"
  local cmdfile="$obj.cmd"
  local cmd=("$CXX" "$@" -MMD -MP -MF "$depfile" -c "$source" -o "$obj")

  mkdir -p "$(dirname "$obj")"
  if ! object_needs_rebuild "$obj" "$depfile" "$cmdfile" "${cmd[@]}"; then
    printf 'up to date: %s\n' "$source" >> "$stdout_log"
    return 0
  fi

  printf 'compile: %s\n' "$source" >> "$stdout_log"
  if "${cmd[@]}" >> "$stdout_log" 2>> "$stderr_log"; then
    write_command_file "$cmdfile" "${cmd[@]}"
    return 0
  fi
  return 1
}

link_needs_rebuild() {
  local output="$1"
  local cmdfile="$2"
  shift 2

  [[ -f "$output" ]] || return 0
  command_matches "$cmdfile" "$@" || return 0

  local arg
  for arg in "$@"; do
    if [[ -f "$arg" && "$arg" -nt "$output" ]]; then
      return 0
    fi
  done
  return 1
}

link_binary() {
  local target="$1"
  local output="$2"
  shift 2

  local stdout_log="$BUILD_DIR/$target.stdout.log"
  local stderr_log="$BUILD_DIR/$target.stderr.log"
  local cmdfile="$output.cmd"
  local cmd=("$CXX" "$@" -o "$output")

  if ! link_needs_rebuild "$output" "$cmdfile" "${cmd[@]}"; then
    printf 'up to date: %s\n' "$output" >> "$stdout_log"
    return 0
  fi

  printf 'link: %s\n' "$output" >> "$stdout_log"
  if "${cmd[@]}" >> "$stdout_log" 2>> "$stderr_log"; then
    write_command_file "$cmdfile" "${cmd[@]}"
    return 0
  fi
  return 1
}

compile_target_objects() {
  local target="$1"
  local flags_name="$2"
  local sources_name="$3"
  local objs_name="$4"

  local -n flags="$flags_name"
  local -n sources="$sources_name"
  local -n objs="$objs_name"
  local obj_dir="$BUILD_DIR/obj/$target"
  local status=0

  objs=()
  local source
  for source in "${sources[@]}"; do
    local base
    base="$(basename "$source")"
    local obj="$obj_dir/${base%.*}.o"
    objs+=("$obj")
    if ! compile_object "$target" "$source" "$obj" "${flags[@]}"; then
      status=1
    fi
  done

  return "$status"
}

build_binary_target() {
  local target="$1"
  local output="$2"
  local flags_name="$3"
  local sources_name="$4"
  local link_flags_name="$5"
  shift 5

  local stdout_log="$BUILD_DIR/$target.stdout.log"
  local stderr_log="$BUILD_DIR/$target.stderr.log"
  : > "$stdout_log"
  : > "$stderr_log"

  local target_objs=()
  local status=0
  if ! compile_target_objects "$target" "$flags_name" "$sources_name" target_objs; then
    status=1
  fi

  if [[ "$status" -eq 0 ]]; then
    local -n link_flags="$link_flags_name"
    if ! link_binary "$target" "$output" "${link_flags[@]}" "${target_objs[@]}" "$@"; then
      status=1
    fi
  fi

  echo "$status" > "$BUILD_DIR/$target.exitcode"
  return "$status"
}

build_object_target() {
  local target="$1"
  local output="$2"
  local source="$3"
  local flags_name="$4"

  local stdout_log="$BUILD_DIR/$target.stdout.log"
  local stderr_log="$BUILD_DIR/$target.stderr.log"
  : > "$stdout_log"
  : > "$stderr_log"

  local -n flags="$flags_name"
  local status=0
  if ! compile_object "$target" "$source" "$output" "${flags[@]}"; then
    status=1
  fi

  echo "$status" > "$BUILD_DIR/$target.exitcode"
  return "$status"
}

NO_LINK_FLAGS=()

INI_PROBE_SOURCES=(
  "$VENDOR_DIR/src/emc/ini/inifile.cc"
  "$WRAP_DIR/linuxcnc_ini_probe.cpp"
)

STATE_PROBE_SOURCES=(
  "$WRAP_DIR/linuxcnc_interp_state_probe.cpp"
)

INTERP_CORE_SOURCES=(
  "$VENDOR_DIR/src/emc/rs274ngc/modal_state.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_array.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_internal.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_read.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_check.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_arc.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_inverse.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_execute.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_convert.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_cycles.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_g7x.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_queue.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_find.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_namedparams.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_write.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/interp_o_word.cc"
  "$VENDOR_DIR/src/emc/rs274ngc/rs274ngc_pre.cc"
  "$WRAP_DIR/linuxcnc_hal_adapter.cpp"
  "$WRAP_DIR/linuxcnc_interp_edge_stubs.cpp"
  "$WRAP_DIR/linuxcnc_runtime_state_stubs.cpp"
  "$WRAP_DIR/linuxcnc_tool_adapter.cpp"
  "$WRAP_DIR/linuxcnc_interp_minimal_runtime.cpp"
  "$VENDOR_DIR/src/emc/ini/inifile.cc"
)

NAMEDPARAM_SOURCES=(
  "${INTERP_CORE_SOURCES[@]}"
  "$WRAP_DIR/linuxcnc_namedparam_harness.cpp"
)

MINIMAL_SOURCES=(
  "${INTERP_CORE_SOURCES[@]}"
  "$WRAP_DIR/linuxcnc_interp_minimal_harness.cpp"
)

PARAMETER_FILE_SOURCES=(
  "${INTERP_CORE_SOURCES[@]}"
  "$WRAP_DIR/linuxcnc_parameter_file_harness.cpp"
)

build_binary_target \
  linuxcnc_ini_probe \
  "$BUILD_DIR/linuxcnc_ini_probe" \
  COMMON_FLAGS \
  INI_PROBE_SOURCES \
  NO_LINK_FLAGS \
  -lfmt

build_binary_target \
  linuxcnc_interp_state_probe \
  "$BUILD_DIR/linuxcnc_interp_state_probe" \
  COMMON_FLAGS \
  STATE_PROBE_SOURCES \
  NO_LINK_FLAGS

build_binary_target \
  linuxcnc_namedparam_harness \
  "$BUILD_DIR/linuxcnc_namedparam_harness" \
  MINIMAL_FLAGS \
  NAMEDPARAM_SOURCES \
  MINIMAL_LINK_FLAGS \
  -lfmt

if [[ "$(tr -d '[:space:]' < "$BUILD_DIR/linuxcnc_namedparam_harness.exitcode")" == "0" ]]; then
  set +e
  "$BUILD_DIR/linuxcnc_namedparam_harness" "$NAMEDPARAM_INI_FIXTURE" \
    >"$BUILD_DIR/linuxcnc_namedparam_harness.run.stdout.log" \
    2>"$BUILD_DIR/linuxcnc_namedparam_harness.run.stderr.log"
  NAMEDPARAM_RUN_RC=$?
  set -e
  echo "$NAMEDPARAM_RUN_RC" > "$BUILD_DIR/linuxcnc_namedparam_harness.run.exitcode"
else
  rm -f \
    "$BUILD_DIR/linuxcnc_namedparam_harness.run.exitcode" \
    "$BUILD_DIR/linuxcnc_namedparam_harness.run.stdout.log" \
    "$BUILD_DIR/linuxcnc_namedparam_harness.run.stderr.log"
fi

build_binary_target \
  linuxcnc_interp_minimal_harness \
  "$BUILD_DIR/linuxcnc_interp_minimal_harness" \
  MINIMAL_FLAGS \
  MINIMAL_SOURCES \
  MINIMAL_LINK_FLAGS \
  -lfmt

if [[ "$(tr -d '[:space:]' < "$BUILD_DIR/linuxcnc_interp_minimal_harness.exitcode")" == "0" ]]; then
  set +e
  "$BUILD_DIR/linuxcnc_interp_minimal_harness" "$MINIMAL_GCODE_FIXTURE" \
    >"$BUILD_DIR/linuxcnc_interp_minimal_harness.run.stdout.log" \
    2>"$BUILD_DIR/linuxcnc_interp_minimal_harness.run.stderr.log"
  INTERP_MIN_RUN_RC=$?
  set -e
  echo "$INTERP_MIN_RUN_RC" > "$BUILD_DIR/linuxcnc_interp_minimal_harness.run.exitcode"
else
  rm -f \
    "$BUILD_DIR/linuxcnc_interp_minimal_harness.run.exitcode" \
    "$BUILD_DIR/linuxcnc_interp_minimal_harness.run.stdout.log" \
    "$BUILD_DIR/linuxcnc_interp_minimal_harness.run.stderr.log"
fi

build_binary_target \
  linuxcnc_parameter_file_harness \
  "$BUILD_DIR/linuxcnc_parameter_file_harness" \
  MINIMAL_FLAGS \
  PARAMETER_FILE_SOURCES \
  MINIMAL_LINK_FLAGS \
  -lfmt

if [[ "$(tr -d '[:space:]' < "$BUILD_DIR/linuxcnc_parameter_file_harness.exitcode")" == "0" ]]; then
  set +e
  "$BUILD_DIR/linuxcnc_parameter_file_harness" \
    >"$BUILD_DIR/linuxcnc_parameter_file_harness.run.stdout.log" \
    2>"$BUILD_DIR/linuxcnc_parameter_file_harness.run.stderr.log"
  PARAMETER_FILE_RUN_RC=$?
  set -e
  echo "$PARAMETER_FILE_RUN_RC" > "$BUILD_DIR/linuxcnc_parameter_file_harness.run.exitcode"
else
  rm -f \
    "$BUILD_DIR/linuxcnc_parameter_file_harness.run.exitcode" \
    "$BUILD_DIR/linuxcnc_parameter_file_harness.run.stdout.log" \
    "$BUILD_DIR/linuxcnc_parameter_file_harness.run.stderr.log"
fi

build_object_target \
  linuxcnc_rs274_compile_probe \
  "$BUILD_DIR/linuxcnc_rs274_compile_probe.o" \
  "$WRAP_DIR/linuxcnc_rs274_compile_probe.cpp" \
  COMMON_FLAGS

build_object_target \
  linuxcnc_interp_convert_source_probe \
  "$BUILD_DIR/linuxcnc_interp_convert_source_probe.o" \
  "$VENDOR_DIR/src/emc/rs274ngc/interp_convert.cc" \
  COMMON_FLAGS

echo "native probes complete"