# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
# vim: set filetype=python:
#  This Source Code Form is subject to the terms of the Mozilla Public
#  License, v. 2.0. If a copy of the MPL was not distributed with this
#  file, You can obtain one at http://mozilla.org/MPL/2.0/.


@template
def noset_check_header(
    header, language="C++", flags=None, includes=None, when=None, onerror=lambda: None
):
    if when is None:
        when = always

    if includes:
        includes = includes[:]
    else:
        includes = []
    includes.append(header)

    return try_compile(
        includes=includes,
        language=language,
        flags=flags,
        check_msg="for %s" % header,
        when=when,
        onerror=onerror,
    )


@template
def check_symbol_exists(
    symbol,
    header,
    language="C",
    flags=None,
    includes=None,
    when=None,
    onerror=lambda: None,
):
    if when is None:
        when = always

    if includes:
        includes = includes[:]
    else:
        includes = []
    includes.append("stdio.h")

    if isinstance(header, str):
        header = [header]
    includes.extend(header)

    body = """#ifndef %s
(void) %s;
#endif
""" % (
        symbol,
        symbol,
    )

    return try_compile(
        includes,
        body,
        language=language,
        flags=flags,
        check_msg="for %s" % symbol,
        when=when,
        onerror=onerror,
    )


with only_when("--enable-compile-environment"):
    option(
        "--with-system-librnp",
        help="Use system RNP (librnp) for OpenPGP support.",
    )

    @depends("--with-system-librnp")
    def in_tree_librnp(system_librnp):
        if system_librnp:
            log.info("System librnp will be used at runtime.")
            return False
        return True

    set_config("MZLA_LIBRNP", depends_if(in_tree_librnp)(lambda _: True))
    set_define("MZLA_LIBRNP", depends_if(in_tree_librnp)(lambda _: True))


with only_when(in_tree_librnp):
    # JSON-C --with-system-json
    system_lib_option(
        "--with-system-jsonc",
        help="Use system JSON-C for librnp (located with pkgconfig)",
    )

    jsonc_pkg = pkg_check_modules("MZLA_JSONC", "json-c >= 0.11", when="--with-system-jsonc")
    set_config("MZLA_SYSTEM_JSONC", depends_if(jsonc_pkg)(lambda _: True))

    @depends("--with-system-jsonc")
    def in_tree_jsonc(system_jsonc):
        if not system_jsonc:
            return True

    # Bzip2 --with-system-bz2
    system_lib_option(
        "--with-system-bz2",
        nargs="?",
        help="Use system Bzip2 for librnp (pkgconfig/given prefix)",
    )
    set_config("MZLA_SYSTEM_BZIP2", True, when="--with-system-bz2")

    # Bzip2 does not include a pkgconfig file, but some Linux distributions add one
    bzip2_pkg = pkg_check_modules(
        "MZLA_BZIP2",
        "bzip2 >= 1.0.6",
        when="--with-system-bz2",
        allow_missing=True,
        config=False,
    )

    @depends_if("--with-system-bz2", bzip2_pkg)
    def bzip2_flags(value, bzip2_pkg):
        if len(value):
            # A path (eg. /usr/local was given)
            return namespace(
                cflags=("-I%s/include" % value[0],),
                ldflags=("-L%s/lib" % value[0], "-lbz2"),
            )
        if bzip2_pkg:
            cflags = list(bzip2_pkg.cflags)
            libs = bzip2_pkg.libs
            return namespace(
                cflags=cflags,
                ldflags=libs,
            )
        # Fallback
        return namespace(
            ldflags=["-lbz2"],
        )

    with only_when("--with-system-bz2"):
        check_symbol(
            "BZ2_bzread",
            flags=bzip2_flags.ldflags,
            onerror=lambda: die("--with-system-bz2 requested but symbol " "BZ2_bzread not found."),
        )
        c_compiler.try_compile(
            includes=[
                "stdio.h",
                "sys/types.h",
                "bzlib.h",
            ],
            body="""
                #ifndef _BZLIB_H
                #error _BZLIB_H bzlib.h not found
                #endif
            """,
            flags=bzip2_flags.cflags,
            check_msg="for bzlib.h",
            onerror=lambda: die("bzlib.h header not found"),
        )
        set_config("MZLA_BZIP2_CFLAGS", bzip2_flags.cflags)
        set_config("MZLA_BZIP2_LIBS", bzip2_flags.ldflags)

    # librnp crypto backend selection
    @depends(target_has_linux_kernel)
    def librnp_backend_choices(is_linux):
        if is_linux:
            return ("botan", "openssl")
        else:
            return ("botan",)

    option(
        "--with-librnp-backend",
        help="Build librnp with the selected backend",
        choices=librnp_backend_choices,
        nargs=1,
        default="botan",
    )

    @depends("--with-librnp-backend")
    def librnp_backend(backend):
        if backend:
            return backend[0]

    set_config("MZLA_LIBRNP_BACKEND", librnp_backend)

    @depends(librnp_backend)
    def rnp_botan(backend):
        return backend == "botan"

    @depends(librnp_backend)
    def rnp_openssl(backend):
        return backend == "openssl"

    # Botan backend (--with-system-botan)
    with only_when(rnp_botan):
        system_lib_option(
            "--with-system-botan",
            help="Use system Botan for librnp (located with pkgconfig)",
        )

        botan_pkg = pkg_check_modules("MZLA_BOTAN", "botan-2 >= 2.8.0", when="--with-system-botan")
        set_config("MZLA_SYSTEM_BOTAN", depends_if(botan_pkg)(lambda _: True))

    # OpenSSL backend
    with only_when(rnp_openssl):
        option(
            "--with-openssl",
            nargs=1,
            help="OpenSSL library prefix (when not found by pkgconfig)",
        )
        openssl_pkg = pkg_check_modules(
            "MZLA_LIBRNP_OPENSSL", "openssl >= 1.1.1e", allow_missing=True, config=False
        )

        @depends_if("--with-openssl", openssl_pkg)
        @imports(_from="os.path", _import="isdir")
        @imports(_from="os.path", _import="join")
        def openssl_flags(openssl_prefix, openssl_pkg):
            if openssl_prefix:
                openssl_prefix = openssl_prefix[0]
                include = join(openssl_prefix, "include")
                lib = join(openssl_prefix, "lib")
                if not isdir(lib):
                    lib = join(openssl_prefix, "lib64")
                if isdir(include) and isdir(lib):
                    log.info(f"Using OpenSSL at {openssl_prefix}.")
                    return namespace(
                        cflags=(f"-I{include}",),
                        ldflags=(f"-L{lib}", "-lssl", "-lcrypto"),
                    )
            if openssl_pkg:
                return namespace(
                    cflags=openssl_pkg.cflags,
                    ldflags=openssl_pkg.libs,
                )

        set_config("MZLA_LIBRNP_OPENSSL_CFLAGS", openssl_flags.cflags)
        set_config("MZLA_LIBRNP_OPENSSL_LIBS", openssl_flags.ldflags)

        @depends(configure_cache, c_compiler, openssl_flags)
        @imports(_from="textwrap", _import="dedent")
        @imports(_from="__builtin__", _import="chr")
        def openssl_version(configure_cache, compiler, openssl_flags):
            log.info("Checking for OpenSSL >= 1.1.1e")
            if openssl_flags is None:
                die("OpenSSL not found. Must be locatable with pkg-config or use --with-openssl.")

            def ossl_hexver(hex_str):
                # See opensshlv.h for description of OPENSSL_VERSION_NUMBER
                MIN_OSSL_VER = 0x1010105F  # Version 1.1.1e
                ver_as_int = int(hex_str[:-1], 16)
                ossl_major = (ver_as_int & 0xF0000000) >> 28
                ossl_minor = (ver_as_int & 0x0FF00000) >> 20
                ossl_fix = (ver_as_int & 0x000FF000) >> 12
                # as a letter a-z
                ossl_patch = chr(96 + ((ver_as_int & 0x00000FF0) >> 4))
                ver_as_str = f"{ossl_major}.{ossl_minor}.{ossl_fix}{ossl_patch}"
                if ver_as_int < MIN_OSSL_VER:
                    die(f"OpenSSL version {ver_as_str} is too old.")
                return ver_as_str

            check = dedent(
                """\
            #include <openssl/opensslv.h>
            #ifdef OPENSSL_VERSION_STR
            OPENSSL_VERSION_STR
            #elif defined(OPENSSL_VERSION_NUMBER)
            OPENSSL_VERSION_NUMBER
            #else
            #error Unable to determine OpenSSL version.
            #endif
                """
            )
            result = try_preprocess(
                configure_cache,
                compiler.wrapper
                + [compiler.compiler]
                + compiler.flags
                + list(openssl_flags.cflags),
                "C",
                check,
            )
            if result:
                openssl_ver = result.splitlines()[-1]
                if openssl_ver.startswith("0x"):
                    # OpenSSL 1.x.x - like 0x1010107fL
                    openssl_ver = ossl_hexver(openssl_ver)
                else:
                    # OpenSSL 3.x.x - quoted version like "3.0.7"
                    openssl_ver = openssl_ver.replace('"', "")
                    major_version = openssl_ver.split(".")[0]
                    if major_version != "3":
                        die(
                            "Unrecognized OpenSSL version {openssl_version} found. Require >= 1.1.1e or 3.x.x"
                        )

                log.info(f"Found OpenSSL {openssl_ver}.")
                return openssl_ver

        set_config("MZLA_LIBRNP_OPENSSL_VERSION", openssl_version)

    # Checks for building librnp itself
    # =================================
    have_fcntl_h = check_header("fcntl.h")
    have_string_h = check_header("string.h")
    check_headers(
        "limits.h",
        "sys/auxv.h",
        "sys/cdefs.h",
        "sys/resource.h",
        "sys/param.h",
        "sys/stat.h",
        "sys/wait.h",
    )

    set_define("HAVE_MKDTEMP", check_symbol_exists("mkdtemp", ["stdlib.h", "unistd.h"]))
    set_define("HAVE_MKSTEMP", check_symbol_exists("mkstemp", ["stdlib.h", "unistd.h"]))
    set_define("HAVE_REALPATH", check_symbol_exists("realpath", "stdlib.h"))
    set_define("HAVE_O_BINARY", check_symbol_exists("O_BINARY", "fcntl.h"))
    set_define("HAVE__O_BINARY", check_symbol_exists("_O_BINARY", "fcntl.h"))

    # Checks when building JSON-C from tree sources
    # =============================================
    with only_when(in_tree_jsonc):
        have_stdlib_h = check_header("stdlib.h")
        have_locale_h = check_header("locale.h")
        have_strings_h = check_header("strings.h")

        check_headers("stdarg.h", "dlfcn.h", "endian.h", "memory.h", "xlocale.h")

        set_define("JSON_C_HAVE_INTTYPES_H", noset_check_header("inttypes.h"))

        set_define("HAVE_DECL__ISNAN", check_symbol_exists("_isnan", "float.h"))

        set_define("HAVE_DECL__FINITE", check_symbol_exists("_finite", "float.h"))
        set_define("HAVE_DECL_INFINITY", check_symbol_exists("INFINITY", "math.h"))
        set_define("HAVE_DECL_ISINF", check_symbol_exists("isinf", "math.h"))
        set_define("HAVE_DECL_ISNAN", check_symbol_exists("isnan", "math.h"))
        set_define("HAVE_DECL_NAN", check_symbol_exists("nan", "math.h"))

        set_define("HAVE_DOPRNT", check_symbol_exists("_doprnt", "stdio.h"))
        set_define("HAVE_SNPRINTF", check_symbol_exists("snprintf", "stdio.h"))
        set_define(
            "HAVE_VASPRINTF",
            check_symbol_exists("vasprintf", "stdio.h", flags=["-D_GNU_SOURCE"]),
        )
        set_define("HAVE_VSNPRINTF", check_symbol_exists("vsnprintf", "stdio.h"))
        set_define("HAVE_VPRINTF", check_symbol_exists("vprintf", "stdio.h"))

        set_define("HAVE_OPEN", check_symbol_exists("open", "fcntl.h", when=have_fcntl_h))
        set_define(
            "HAVE_REALLOC",
            check_symbol_exists("realloc", "stdlib.h", when=have_stdlib_h),
        )
        set_define(
            "HAVE_SETLOCALE",
            check_symbol_exists("setlocale", "locale.h", when=have_locale_h),
        )
        set_define(
            "HAVE_USELOCALE",
            check_symbol_exists("uselocale", "locale.h", when=have_locale_h),
        )
        set_define(
            "HAVE_STRCASECMP",
            check_symbol_exists("strcasecmp", "strings.h", when=have_strings_h),
        )
        set_define(
            "HAVE_STRNCASECMP",
            check_symbol_exists("strncasecmp", "strings.h", when=have_strings_h),
        )
        set_define("HAVE_STRDUP", check_symbol_exists("strdup", "string.h", when=have_string_h))