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

cd "$(dirname "$0")"

# LinuxCNC source basis: object probes compile the core entries selected from
# linuxcnc-rs274-wasm-source-files.txt, including src/emc/rs274ngc,
# src/emc/tooldata/tooldata_common.cc, src/emc/ini/inifile.cc, and
# src/emc/nml_intf/emcops.cc, together with CMake-listed wasm-safe project
# bridge sources and shims that replace the manifest's blocked Python, dlopen,
# tooldata mmap, HAL, and runtime edges.
usage() {
    echo "usage: $0 --mode source-objects|rs274ngc-pre|runtime [manifest]" >&2
}

mode=
manifest=linuxcnc-rs274-wasm-source-files.txt
while [[ "$#" -gt 0 ]]; do
    case "$1" in
        --mode)
            if [[ "$#" -lt 2 ]]; then
                echo "missing --mode value" >&2
                exit 1
            fi
            mode=$2
            shift 2
            ;;
        --help|-h)
            usage
            exit 0
            ;;
        --*)
            usage
            echo "unknown wasm probe object cache option: $1" >&2
            exit 1
            ;;
        *)
            manifest=$1
            shift
            ;;
    esac
done
case "$mode" in
    source-objects|rs274ngc-pre|runtime)
        ;;
    "")
        usage
        echo "missing --mode" >&2
        exit 1
        ;;
    *)
        usage
        echo "unknown wasm probe object cache mode: $mode" >&2
        exit 1
        ;;
esac

linuxcnc_root=${LINUXCNC_ROOT:-../linuxcnc}
cxx=${CXX:-g++}
if [[ -z ${CXX:-} ]] && command -v ccache >/dev/null 2>&1; then
    cxx="ccache $cxx"
fi
build_jobs=${CNC_SIM_BUILD_JOBS:-8}
if ! [[ "$build_jobs" =~ ^[1-9][0-9]*$ ]]; then
    echo "CNC_SIM_BUILD_JOBS must be a positive integer: $build_jobs" >&2
    exit 1
fi
cache_dir=${CNC_SIM_WASM_PROBE_OBJECT_CACHE_DIR-build/wasm-probe-object-cache}
if [[ -z "$cache_dir" ]]; then
    echo "CNC_SIM_WASM_PROBE_OBJECT_CACHE_DIR must not be empty" >&2
    exit 1
fi
if [[ "$cache_dir" =~ [[:space:]] ]]; then
    echo "CNC_SIM_WASM_PROBE_OBJECT_CACHE_DIR must not contain whitespace: $cache_dir" >&2
    exit 1
fi
mkdir -p "$cache_dir"
cache_dir=$(cd "$cache_dir" && pwd)
if [[ "$cache_dir" == "/" ]]; then
    echo "CNC_SIM_WASM_PROBE_OBJECT_CACHE_DIR must not be the filesystem root" >&2
    exit 1
fi

preflight_cache_dir=${CNC_SIM_PREFLIGHT_CACHE_DIR:-"$cache_dir/preflight-cache"}
LINUXCNC_ROOT="$linuxcnc_root" ./check-linuxcnc-inputs-cached.sh --cache-dir "$preflight_cache_dir" "$manifest" --require-rs274-complete
manifest=$(cd "$(dirname "$manifest")" && pwd)/$(basename "$manifest")
linuxcnc_root=$(cd "$linuxcnc_root" && pwd)

common_flag_profile=core20-sections
case "$mode" in
    source-objects)
        common_flag_profile=core20
        ;;
esac
common_flag_output=$(LINUXCNC_ROOT="$linuxcnc_root" ./list-linuxcnc-wasm-common-cxxflags.sh --profile "$common_flag_profile")
mapfile -t common_flags <<<"$common_flag_output"
case "$mode" in
    runtime)
        common_flags+=(-DCNC_SIM_ENABLE_LINUXCNC_RS274_BACKEND)
        ;;
esac

grep -F 'LinuxCNC source basis: wasm-safe project probe sources are the thin bridge' list-linuxcnc-wasm-safe-project-sources.sh >/dev/null
grep -F 'LinuxCNC source basis: wasm-safe shim probe sources are limited to the' list-linuxcnc-wasm-safe-shims.sh >/dev/null

sources=()
shim_output=$(./list-linuxcnc-wasm-safe-shims.sh)
mapfile -t shim_sources <<<"$shim_output"
sources+=("${shim_sources[@]}")
case "$mode" in
    source-objects)
        ;;
    rs274ngc-pre|runtime)
        project_source_output=$(./list-linuxcnc-wasm-safe-project-sources.sh)
        if [[ -n "$project_source_output" ]]; then
            mapfile -t project_sources <<<"$project_source_output"
            sources+=("${project_sources[@]}")
        fi
        ;;
esac
source_output=$(CNC_SIM_PREFLIGHT_CACHE_DIR="$preflight_cache_dir" LINUXCNC_ROOT="$linuxcnc_root" ./list-linuxcnc-wasm-manifest-sources.sh "$manifest" core full)
mapfile -t linuxcnc_sources <<<"$source_output"
sources+=("${linuxcnc_sources[@]}")
for source in "${sources[@]}"; do
    if [[ -z "$source" ]]; then
        echo "wasm probe object source list contains an empty path" >&2
        exit 1
    fi
done

mode_dir="$cache_dir/$mode"
mkdir -p "$mode_dir"
exec 8>"$mode_dir/objects.lock"
flock 8

objects=()
object_index=0
for source in "${sources[@]}"; do
    objects+=("$mode_dir/source_${object_index}.o")
    object_index=$((object_index + 1))
done

signature="$mode_dir/objects.signature"
next_signature="$mode_dir/objects.signature.next"
{
    printf 'CXX=%s\n' "$cxx"
    printf 'PWD=%s\n' "$PWD"
    printf 'LINUXCNC_ROOT=%s\n' "$linuxcnc_root"
    printf 'MANIFEST=%s\n' "$manifest"
    printf 'MODE=%s\n' "$mode"
    printf 'BUILD_RULE_VERSION=1\n'
    printf 'COMMON_FLAGS='
    printf ' %s' "${common_flags[@]}"
    printf '\n'
    printf 'SOURCES:\n'
    printf '%s\n' "${sources[@]}"
} > "$next_signature"
if [[ ! -f "$signature" ]] || ! cmp -s "$signature" "$next_signature"; then
    rm -f "$mode_dir"/source_*.o "$mode_dir"/source_*.d
fi
mv "$next_signature" "$signature"

makefile="$mode_dir/objects.mk"
{
    printf 'CXX := %s\n' "$cxx"
    printf 'COMMON_FLAGS :='
    printf ' %s' "${common_flags[@]}"
    printf '\n\n'
    printf 'OBJECTS :='
    printf ' %s' "${objects[@]}"
    printf '\n\n'
    printf 'DEP_FILES :=\n'
    for object in "${objects[@]}"; do
        printf 'DEP_FILES += %s.d\n' "$object"
    done
    printf '\n.PHONY: all\n'
    printf 'all: $(OBJECTS)\n\n'

    object_index=0
    for source in "${sources[@]}"; do
        source_flags=()
        case "$source" in
            core/src/linuxcnc_corexykins_adapter.c|core/src/linuxcnc_genserfuncs_adapter.c|core/src/linuxcnc_xyzab_tdr_kins_adapter.c)
                source_flags+=(-fpermissive)
                ;;
        esac
        printf '%s: %s\n' "${objects[$object_index]}" "$source"
        printf '\t@$(CXX) $(COMMON_FLAGS)'
        printf ' %s' "${source_flags[@]}"
        printf ' -MMD -MP -MF %s.d -c %s -o %s\n\n' "${objects[$object_index]}" "$source" "${objects[$object_index]}"
        object_index=$((object_index + 1))
    done
    printf '\n-include $(DEP_FILES)\n'
} > "$makefile"
make --output-sync=target -j"$build_jobs" -f "$makefile" >/dev/null

printf '%s\n' "${objects[@]}"