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

ROOT_DIR="$(cd "$(dirname "$0")/.." && pwd)"
UPSTREAM_RS274="$ROOT_DIR/../linuxcnc/bin/rs274"
GCODE_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/gcode"
CANON_FIXTURE_DIR="$ROOT_DIR/tests/fixtures/canon"

FIXTURES=(
  minimal_linear
  length_units
  plane_selection
  modal_incremental
)

if [[ ! -x "$UPSTREAM_RS274" ]]; then
  echo "missing upstream rs274 executable: $UPSTREAM_RS274" >&2
  exit 1
fi

TMP_DIR="$(mktemp -d)"
trap 'rm -rf "$TMP_DIR"' EXIT

normalize_standalone_events() {
  awk '
    function norm(value) {
      return sprintf("%.12g", value + 0)
    }

    /^canon_event=/ {
      line = $0
      sub(/^canon_event=/, "", line)

      if (line ~ /^SELECT_PLANE plane=/) {
        value = line
        sub(/^SELECT_PLANE plane=/, "", value)
        if (value == "1") {
          print "SELECT_PLANE|XY"
        } else if (value == "2") {
          print "SELECT_PLANE|YZ"
        } else if (value == "3") {
          print "SELECT_PLANE|XZ"
        }
        next
      }

      if (line ~ /^USE_LENGTH_UNITS units=/) {
        value = line
        sub(/^USE_LENGTH_UNITS units=/, "", value)
        if (value == "1") {
          print "USE_LENGTH_UNITS|INCHES"
        } else if (value == "2") {
          print "USE_LENGTH_UNITS|MM"
        }
        next
      }

      if (line ~ /^SET_FEED_RATE rate=/) {
        value = line
        sub(/^SET_FEED_RATE rate=/, "", value)
        print "SET_FEED_RATE|" norm(value)
        next
      }

      if (line ~ /^STRAIGHT_(TRAVERSE|FEED) /) {
        split(line, fields, /[[:space:]]+/)
        for (i in fields) {
          split(fields[i], pair, "=")
          values[pair[1]] = pair[2]
        }
        print fields[1] "|" norm(values["x"]) "|" norm(values["y"]) "|" \
          norm(values["z"]) "|" norm(values["a"]) "|" norm(values["b"]) "|" \
          norm(values["c"])
        delete values
        next
      }
    }
  '
}

normalize_upstream_rs274_output() {
  awk '
    function norm(value) {
      return sprintf("%.12g", value + 0)
    }

    function args_of(call, args) {
      args = call
      sub(/^[^(]+\(/, "", args)
      sub(/\).*$/, "", args)
      gsub(/[[:space:]]/, "", args)
      return args
    }

    /^[[:space:]]*[0-9]+[[:space:]]+N\.\.\.\.\./ {
      line = $0
      sub(/^[[:space:]]*[0-9]+[[:space:]]+N\.\.\.\.\.[[:space:]]+/, "", line)

      if (line == "ON_RESET()") {
        seen_reset = 1
        next
      }

      if (!seen_reset) {
        next
      }

      if (line ~ /^SELECT_PLANE\(CANON_PLANE_/) {
        value = line
        sub(/^SELECT_PLANE\(CANON_PLANE_/, "", value)
        sub(/\)$/, "", value)
        print "SELECT_PLANE|" value
        next
      }

      if (line ~ /^USE_LENGTH_UNITS\(CANON_UNITS_/) {
        value = line
        sub(/^USE_LENGTH_UNITS\(CANON_UNITS_/, "", value)
        sub(/\)$/, "", value)
        print "USE_LENGTH_UNITS|" value
        next
      }

      if (line ~ /^SET_FEED_RATE\(/) {
        args = args_of(line)
        print "SET_FEED_RATE|" norm(args)
        next
      }

      if (line ~ /^STRAIGHT_(TRAVERSE|FEED)\(/) {
        op = line
        sub(/\(.*/, "", op)
        args = args_of(line)
        split(args, values, ",")
        print op "|" norm(values[1]) "|" norm(values[2]) "|" norm(values[3]) "|" \
          norm(values[4]) "|" norm(values[5]) "|" norm(values[6])
        next
      }
    }
  '
}

for name in "${FIXTURES[@]}"; do
  gcode_file="$GCODE_FIXTURE_DIR/$name.ngc"
  expected_file="$CANON_FIXTURE_DIR/$name.events"
  native_raw="$TMP_DIR/$name.rs274.raw"
  native_norm="$TMP_DIR/$name.rs274.normalized"
  expected_norm="$TMP_DIR/$name.expected.normalized"

  if [[ ! -f "$gcode_file" ]]; then
    echo "missing G-code fixture: $gcode_file" >&2
    exit 1
  fi

  if [[ ! -f "$expected_file" ]]; then
    echo "missing canonical fixture: $expected_file" >&2
    exit 1
  fi

  set +e
  "$UPSTREAM_RS274" -g "$gcode_file" > "$native_raw" 2>&1
  rs274_rc=$?
  set -e

  if [[ "$rs274_rc" != "0" ]] && ! grep -Fq "File ended with no percent sign (%) or program end (M2)" "$native_raw"; then
    echo "upstream rs274 failed for fixture: $name" >&2
    sed -n '1,160p' "$native_raw" >&2
    exit 1
  fi

  normalize_upstream_rs274_output < "$native_raw" > "$native_norm"
  normalize_standalone_events < "$expected_file" > "$expected_norm"

  if [[ ! -s "$native_norm" ]]; then
    echo "no normalized upstream rs274 events for fixture: $name" >&2
    sed -n '1,160p' "$native_raw" >&2
    exit 1
  fi

  if ! diff -u "$expected_norm" "$native_norm"; then
    echo "native LinuxCNC rs274 baseline mismatch for fixture: $name" >&2
    exit 1
  fi
done

echo "native LinuxCNC fixture baseline validation complete"