load("@rules_cc//cc:defs.bzl", "cc_binary", "cc_library")
load("@rules_python//python:defs.bzl", "py_library")
load("@rules_python//python:pip.bzl", "whl_filegroup")
load("@swig//:swig.bzl", "swig_library")

package(default_visibility = ["//visibility:public"])

# Extract NumPy headers from pip package
whl_filegroup(
    name = "numpy_headers",
    pattern = "numpy/_core/include/numpy",
    whl = "@nlopt_pip//numpy:whl",
)

cc_library(
    name = "numpy_cc_headers",
    hdrs = [":numpy_headers"],
    includes = [
        "numpy_headers/numpy/_core/include",
    ],
)

# Generate nlopt-enum-renames.i from nlopt.h
genrule(
    name = "generate_enum_renames",
    srcs = ["//:src/api/nlopt.h"],
    outs = ["nlopt-enum-renames.i"],
    cmd = """
        echo "// AUTOMATICALLY GENERATED -- DO NOT EDIT" > $@
        # Extract NLOPT_ enum constants and generate SWIG rename directives
        while IFS= read -r line; do
            if echo "$$line" | grep -q '    NLOPT_[A-Z0-9_]'; then
                enum_name=$$(echo "$$line" | sed -E 's/.*NLOPT_([A-Z0-9_]+).*/\\1/')
                echo "%%rename(NLOPT_$$enum_name) nlopt::$$enum_name;" >> $@
            fi
        done < $(location //:src/api/nlopt.h)
    """,
)

# Generate Python wrapper using SWIG
swig_library(
    name = "swig_python",
    srcs = [
        "nlopt.i",
        "nlopt-python.i",
        "nlopt-exceptions.i",
        "numpy.i",
        ":generate_enum_renames",
        "//:src/api/nlopt.h",
        "//:generate_cpp_header",  # nlopt.hpp
    ],
    language = "python",
    module = "nlopt",
    defines = ["SWIGPYTHON"],
)

# Python extension module (_nlopt.so)
cc_binary(
    name = "_nlopt.so",
    srcs = [":swig_python"],
    copts = [
        "-fPIC",
        "-Wno-unused-parameter",
        "-Wno-missing-field-initializers",
        "-Wno-deprecated-declarations",
        "-Wno-unused-variable",
        "-Wno-unused-but-set-variable",
        "-Wno-maybe-uninitialized",
        "-Wno-nonnull",
    ] + select({
        "@platforms//os:windows": ["/D_CRT_SECURE_NO_WARNINGS"],
        "//conditions:default": [],
    }),
    linkshared = True,
    linkstatic = False,
    linkopts = select({
        "@platforms//os:macos": [
            "-undefined",
            "dynamic_lookup",
        ],
        "//conditions:default": [],
    }),
    deps = [
        "//:nlopt",
        ":numpy_cc_headers",
        "@rules_python//python/cc:current_py_cc_headers",
    ],
)

# Python library
py_library(
    name = "nlopt_python",
    srcs = [":swig_python"],
    data = [":_nlopt.so"],
    imports = ["."],
)

# Convenience filegroup for installation
filegroup(
    name = "python_lib",
    srcs = [
        ":swig_python",
        ":_nlopt.so",
    ],
)