# 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/.
#
# ToCAsciiArray and ToCArray are from V8's js2c.py.
#
# Copyright 2012 the V8 project authors. All rights reserved.
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
#     * Redistributions of source code must retain the above copyright
#       notice, this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above
#       copyright notice, this list of conditions and the following
#       disclaimer in the documentation and/or other materials provided
#       with the distribution.
#     * Neither the name of Google Inc. nor the names of its
#       contributors may be used to endorse or promote products derived
#       from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

# This utility converts JS files containing self-hosted builtins into a C
# header file that can be embedded into SpiderMonkey.
#
# It uses the C preprocessor to process its inputs.

from __future__ import with_statement

import errno
import re
import sys
import os
import subprocess
import shlex

import buildconfig
import mozpack.path as mozpath
from mozfile import which
from mozbuild.util import ensure_bytes


def ToCAsciiArray(lines):
    result = []
    for chr in lines:
        value = ord(chr)
        assert value < 128
        result.append(str(value))
    return ", ".join(result)


def ToCArray(lines):
    result = []
    for chr in lines:
        result.append(str(chr))
    return ", ".join(result)


HEADER_TEMPLATE = """\
/* 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/. */

namespace js {
namespace %(namespace)s {
    static const %(sources_type)s data[] = { %(sources_data)s };

    static const %(sources_type)s * const %(sources_name)s = reinterpret_cast<const %(sources_type)s *>(data);

    uint32_t GetCompressedSize() {
        return %(compressed_total_length)i;
    }

    uint32_t GetRawScriptsSize() {
        return %(raw_total_length)i;
    }
} // selfhosted
} // js
"""  # NOQA: E501


def embed(
    cxx, preprocessorOption, cppflags, msgs, sources, c_out, js_out, namespace, env
):
    objdir = os.getcwd()
    # Use relative pathnames to avoid path translation issues in WSL.
    combinedSources = "\n".join(
        [msgs]
        + [
            '#include "%(s)s"' % {"s": mozpath.relpath(source, objdir)}
            for source in sources
        ]
    )
    args = cppflags + ["-D%(k)s=%(v)s" % {"k": k, "v": env[k]} for k in env]
    preprocessed = preprocess(cxx, preprocessorOption, combinedSources, args)
    processed = "\n".join(
        [
            line
            for line in preprocessed.splitlines()
            if (line.strip() and not line.startswith("#"))
        ]
    )

    js_out.write(processed)
    import zlib

    compressed = zlib.compress(ensure_bytes(processed))
    data = ToCArray(compressed)
    c_out.write(
        HEADER_TEMPLATE
        % {
            "sources_type": "unsigned char",
            "sources_data": data,
            "sources_name": "compressedSources",
            "compressed_total_length": len(compressed),
            "raw_total_length": len(processed),
            "namespace": namespace,
        }
    )


def preprocess(cxx, preprocessorOption, source, args=[]):
    if not os.path.exists(cxx[0]):
        binary = cxx[0]
        cxx[0] = which(binary)
        if not cxx[0]:
            raise OSError(errno.ENOENT, "%s not found on PATH" % binary)

    # Clang seems to complain and not output anything if the extension of the
    # input is not something it recognizes, so just fake a .cpp here.
    tmpIn = "self-hosting-cpp-input.cpp"
    tmpOut = "self-hosting-preprocessed.pp"
    outputArg = shlex.split(preprocessorOption + tmpOut)

    with open(tmpIn, "wb") as input:
        input.write(ensure_bytes(source))
    print(" ".join(cxx + outputArg + args + [tmpIn]))
    result = subprocess.Popen(cxx + outputArg + args + [tmpIn]).wait()
    if result != 0:
        sys.exit(result)
    with open(tmpOut, "r") as output:
        processed = output.read()
    os.remove(tmpIn)
    os.remove(tmpOut)
    return processed


def messages(jsmsg):
    defines = []
    for line in open(jsmsg):
        match = re.match("MSG_DEF\((JSMSG_(\w+))", line)
        if match:
            defines.append("#define %s %i" % (match.group(1), len(defines)))
        else:
            # Make sure that MSG_DEF isn't preceded by whitespace
            assert not line.strip().startswith("MSG_DEF")
    return "\n".join(defines)


def get_config_defines(buildconfig):
    # Collect defines equivalent to ACDEFINES and add MOZ_DEBUG_DEFINES.
    env = buildconfig.defines["ALLDEFINES"]
    for define in buildconfig.substs["MOZ_DEBUG_DEFINES"]:
        env[define] = 1
    return env


def process_inputs(namespace, c_out, msg_file, inputs):
    deps = [path for path in inputs if path.endswith(".h") or path.endswith(".h.js")]
    sources = [
        path for path in inputs if path.endswith(".js") and not path.endswith(".h.js")
    ]
    assert len(deps) + len(sources) == len(inputs)
    cxx = shlex.split(buildconfig.substs["CXX"])
    pp_option = buildconfig.substs["PREPROCESS_OPTION"]
    cppflags = buildconfig.substs["OS_CPPFLAGS"]
    cppflags += shlex.split(buildconfig.substs["WARNINGS_AS_ERRORS"])
    env = get_config_defines(buildconfig)
    js_path = re.sub(r"\.out\.h$", "", c_out.name) + ".js"
    msgs = messages(msg_file)
    with open(js_path, "w") as js_out:
        embed(cxx, pp_option, cppflags, msgs, sources, c_out, js_out, namespace, env)


def generate_selfhosted(c_out, msg_file, *inputs):
    # Called from moz.build to embed selfhosted JS.
    process_inputs("selfhosted", c_out, msg_file, inputs)


def generate_shellmoduleloader(c_out, msg_file, *inputs):
    # Called from moz.build to embed shell module loader JS.
    process_inputs("moduleloader", c_out, msg_file, inputs)