#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright (C) 2020 Apple Inc.  All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. 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.
#
# THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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 script generates the source files for WebGL GPU process IPC.
#
# python3 -m black -l 150 Tools/Scripts/generate-gpup-webgl
# python3 -m mypy Tools/Scripts/generate-gpup-webgl
#
import argparse
import enum
import pathlib
import re
import sys
import collections

from typing import List, Dict, Iterable, Callable, Tuple, Set, Optional, Generator, Iterator, Counter

root_dir = (pathlib.Path(__file__).parent / ".." / "..").resolve()
extensions_input_fn = root_dir / "Source" / "WebCore" / "platform" / "graphics" / "ExtensionsGL.h"

functions_input_fns = [
    root_dir / "Source" / "WebKit" / "WebProcess" / "GPU" / "graphics" / "RemoteGraphicsContextGLProxy.h"
]
types_input_fn = root_dir / "Source" / "WebKit" / "WebProcess" / "GPU" / "graphics" / "RemoteGraphicsContextGLProxy.h"


template_preamble = """/* Copyright (C) 2020 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  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.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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 file is generated by generate-gpup-webgl. Do not edit.
"""
context_functions_fn = root_dir / "Source" / "WebKit" / "GPUProcess" / "graphics" / "RemoteGraphicsContextGLFunctionsGenerated.h"
context_functions_template = (
    template_preamble
    + """// This file should be included in the private section of the
// RemoteGraphicsContextGL implementations.
#pragma once
{}

"""
)
context_messages_fn = root_dir / "Source" / "WebKit" / "GPUProcess" / "graphics" / "RemoteGraphicsContextGL.messages.in"
context_messages_template = (
    template_preamble
    + """#if ENABLE(GPU_PROCESS) && ENABLE(WEBGL)

messages -> RemoteGraphicsContextGL NotRefCounted Stream {{
    void Reshape(int32_t width, int32_t height)
#if PLATFORM(COCOA)
    void PrepareForDisplay() -> (MachSendRight displayBuffer) Synchronous NotStreamEncodableReply
#endif
#if !PLATFORM(COCOA)
    void PrepareForDisplay() -> () Synchronous
#endif
    void EnsureExtensionEnabled(String extension)
    void NotifyMarkContextChanged()
    void SynthesizeGLError(uint32_t error)
    void GetError() -> (uint32_t returnValue) Synchronous
    void PaintRenderingResultsToCanvas(WebCore::RenderingResourceIdentifier imageBuffer) -> () Synchronous
    void PaintCompositedResultsToCanvas(WebCore::RenderingResourceIdentifier imageBuffer) -> () Synchronous
    void CopyTextureFromMedia(WebCore::MediaPlayerIdentifier identifier, uint32_t texture, uint32_t target, int32_t level, uint32_t internalFormat, uint32_t format, uint32_t type, bool premultiplyAlpha, bool flipY) -> (bool success) Synchronous
    void SimulateEventForTesting(WebCore::GraphicsContextGL::SimulatedEventForTesting event)
{}
}}

#endif
"""
)

context_proxy_functions_fn = root_dir / "Source" / "WebKit" / "WebProcess" / "GPU" / "graphics" / "RemoteGraphicsContextGLProxyFunctionsGenerated.cpp"
context_proxy_functions_template = (
    template_preamble
    + """
#include "config.h"
#include "RemoteGraphicsContextGLProxy.h"

#if ENABLE(GPU_PROCESS) && ENABLE(WEBGL)

namespace WebKit {{
{}

}}

#endif

"""
)


def write_file(fn, new_contents):
    try:
        with open(fn) as f:
            if f.read() == new_contents:
                return
    except:
        pass
    with open(fn, "w") as f:
        f.write(new_contents)

class cpp_type(object):
    type_name: str

    def __init__(self, type_name : str):
        self.type_name = type_name

    def __str__(self):
        return self.type_name

    def __hash__(self):
        return hash(self.type_name)

    def __repr__(self):
        return self.type_name

    def __eq__(self, other):
        return self.type_name == other.type_name

    def is_void(self) -> bool:
        return self.type_name in ["void", "GCGLvoid", "const void", "const GCGLvoid"]

    def is_const(self) -> bool:
        return self.type_name.startswith("const ")

    def is_container(self) -> bool:
        return False

    def is_output_buffer_type(self) -> bool:
        return False

    def is_span(self) -> bool:
        return False

    def is_dynamic_span(self) -> bool:
        return False

    def is_pointer(self) -> bool:
        return False

    def is_const_pointer(self) -> bool:
        return False

    def is_reference(self) -> bool:
        return False

    def is_const_reference(self) -> bool:
        return False

    def get_value_type(self) -> 'cpp_type':
        return self

    def get_decay_type(self) -> 'cpp_type':
        if self.is_const():
            return get_cpp_type(self.type_name[6:])
        return self

    def get_rvalue_type(self) -> 'cpp_type':
        return get_cpp_type(self.type_name + "&&")

    def get_pointer_type(self) -> 'cpp_type':
        return get_cpp_type(self.type_name + "*")

class cpp_type_container(cpp_type):
    def __init__(self, type_name : str, container_name : str, contained_type : cpp_type, arity : Optional[int] = None):
        cpp_type.__init__(self, type_name)
        self.container_name = container_name
        self.contained_type = contained_type
        self.arity = arity
    def is_container(self) -> bool:
        return True
    def is_span(self) -> bool:
        return self.container_name == "GCGLSpan"
    def is_dynamic_span(self) -> bool:
        return self.container_name == "GCGLSpan" and self.arity is None
    def get_container_name(self):
        return self.container_name
    def get_arity(self) -> Optional[int]:
        return self.arity
    def get_contained_type(self) -> cpp_type:
        return self.contained_type
    def is_output_buffer_type(self) -> bool:
        return self.contained_type.is_const()

def create_cpp_type_container(type_name : str) -> Optional[cpp_type_container]:
    # The logic to determine container is to just assume all templates are containers.
    m = re.match(r"([\w:]+)<(.+)>$", type_name)
    if not m:
        return None
    container_name = m[1]
    # All templates are containers except these below.
    if container_name in ['RefPtr', 'Ref']:
        return None
    templates = m[2]
    arity = None
    m = re.match(r"([^,]+),\s*(\d+)", templates)
    if m:
        templates = m[1]
        arity = int(m[2])
    return cpp_type_container(type_name, container_name, get_cpp_type(templates), arity)

class cpp_type_function(cpp_type):
    def __init__(self, type_name : str, return_value_type : cpp_type, argument_types : List[cpp_type]):
        cpp_type.__init__(self, type_name)
        self.return_value_type  = return_value_type
        self.argument_types = argument_types

def cpp_split_args_specs(args_spec : str) -> Iterator[str]:
     # https://stackoverflow.com/questions/33527245/python-split-by-comma-skipping-the-content-inside-parentheses
    comma = r",(?!(?:[^<]*\<[^>]*\>)*[^<>]*\>)"
    return filter(None, [a.strip() for a in re.split(comma, args_spec.strip())])

def create_cpp_type_function(type_name : str) -> Optional[cpp_type_function]:
    m = re.match(r'(.*)\((.*)\)', type_name)
    if not m:
        return None
    return_value_type = get_cpp_type(m[1])
    args_types = [get_cpp_type(a) for a in cpp_split_args_specs(m[2])]
    return cpp_type_function(type_name, return_value_type, args_types)

# Pointer or refererence
class cpp_type_indirect(cpp_type):
    category : str
    value_type : cpp_type

    def __init__(self, type_name : str, category : str, value_type : cpp_type):
        cpp_type.__init__(self, type_name)
        self.category = category
        self.value_type = value_type

    def is_const_pointer(self):
        return self.category == '*' and self.is_const()
    def is_pointer(self):
        return self.category == '*' and not self.is_const()
    def is_const_reference(self):
        return self.category == '&' and self.is_const()
    def is_reference(self):
        return self.category == '&' and not self.is_const()
    def is_rvalue_reference(self):
        return self.category == '&&'
    def get_value_type(self):
        return self.value_type

def create_cpp_type_indirect(type_name : str) -> Optional[cpp_type_indirect]:
    m = re.match(r"const (.+)&&$", type_name)
    if not m:
        m = re.match(r"(.+)&&$", type_name)
    if m:
        return cpp_type_indirect(type_name, '&&', get_cpp_type(m[1]))
    m = re.match(r"const (.+)&$", type_name)
    if not m:
        m = re.match(r"(.+)&$", type_name)
    if m:
        return cpp_type_indirect(type_name, '&', get_cpp_type(m[1]))
    m = re.match(r"const (.+)\*$", type_name)
    if not m:
        m = re.match(r"(.+)\*$", type_name)
    if m:
        return cpp_type_indirect(type_name, '*', get_cpp_type(m[1]))
    return None


class cpp_expr(object):
    type: cpp_type
    expr: str

    def __init__(self, type: cpp_type, expr: str):
        self.type = type
        self.expr = expr

    def __str__(self):
        return self.expr


CppExprConverter = Callable[[cpp_expr, cpp_type], cpp_expr]


def cpp_reinterpret_cast_from_pointer_through(cast_through_type : cpp_type) -> Callable[[cpp_expr, cpp_type], cpp_expr]:
    def cpp_reinterpret_cast_from_pointer(expr: cpp_expr, type: cpp_type) -> cpp_expr:
        return cpp_expr(type, f"static_cast<{type.type_name}>(reinterpret_cast<{str(cast_through_type)}>({str(expr)}))")
    return cpp_reinterpret_cast_from_pointer

def cpp_reinterpret_cast_to_pointer_through(cast_through_type : cpp_type) -> Callable[[cpp_expr, cpp_type], cpp_expr]:
    def cpp_reinterpret_cast_to_pointer(expr: cpp_expr, type: cpp_type) -> cpp_expr:
        return cpp_expr(type, f"reinterpret_cast<{type.type_name}>(static_cast<{str(cast_through_type)}>({str(expr)}))")
    return cpp_reinterpret_cast_to_pointer

def cpp_static_cast(expr: cpp_expr, type: cpp_type) -> cpp_expr:
    return cpp_expr(type, f"static_cast<{type.type_name}>({str(expr)})")


def cpp_implicit_cast(expr: cpp_expr, type: cpp_type) -> cpp_expr:
    return cpp_expr(type, str(expr))


def cpp_array_reinterpret_cast_conversion(expr: cpp_expr, type: cpp_type_container) -> cpp_expr:
    element_pointer_type = type.get_contained_type().get_pointer_type()
    return cpp_expr(type, f"{str(type)}(reinterpret_cast<{element_pointer_type}>({str(expr)}.data()), {str(expr)}.size())")

def webkit_ipc_span_transfer_type_reinterpret_cast_conversion(expr: cpp_expr, type: cpp_type_container) -> cpp_expr:
    element_pointer_type = type.get_contained_type().get_pointer_type()
    return cpp_expr(type, f"{str(type)}(reinterpret_cast<const {element_pointer_type}>({str(expr)}.data), {str(expr)}.bufSize)")

def cpp_move_expr(expr: cpp_expr) -> cpp_expr:
    return cpp_expr(expr.type.get_rvalue_type(), f"WTFMove({str(expr)})")


cpp_types: Dict[str, cpp_type] = {}

cpp_type_constructors : List[Callable[[str], Optional[cpp_type]]] = [
    create_cpp_type_function,
    create_cpp_type_container,
    create_cpp_type_indirect
]

def get_cpp_type(type_name: str):
    r = cpp_types.get(type_name, None)
    if r:
        return r
    for type_constr in cpp_type_constructors:
        r = type_constr(type_name)
        if r:
            break
    if not r:
        r = cpp_type(type_name)
    cpp_types[type_name] = r
    return r


class cpp_arg(object):
    name: str
    type: cpp_type

    def __init__(self, type: cpp_type, name: str):
        self.name = name
        self.type = type

    def __str__(self):
        return "{} {}".format(self.type, self.name)


class cpp_decl(object):
    type: cpp_type
    name: str

    def __init__(self, type: cpp_type, name: str):
        self.type = type
        self.name = name

    def __str__(self):
        return f"{str(self.type)} {self.name}"


class cpp_arg_list(object):
    args: List[cpp_arg]

    def __init__(self, args: List[cpp_arg]):
        self.args = args

    def names(self):
        return ", ".join(a.name for a in self.args)

    def exprs(self):
        return [cpp_expr(a.type, a.name) for a in self.args]

    def decls(self):
        return [cpp_decl(a.type, a.name) for a in self.args]

    def types(self):
        return [a.type for a in self.args]

    def __str__(self):
        return ", ".join(str(a) for a in self.args)


class cpp_func(object):
    name: str
    args: cpp_arg_list
    return_type: cpp_type
    is_extension: bool
    overload_suffix: str

    def __init__(self, name: str, return_type: cpp_type, args: cpp_arg_list, is_extension: bool):
        self.name = name
        self.return_type = return_type
        self.args = args
        self.is_extension = is_extension
        self.overload_suffix = ""

    def __str__(self):
        return f"{self.return_type} {self.name}({str(self.args)})"

    def get_args_categories(self) -> Tuple[List[cpp_arg], List[cpp_arg]]:
        in_args = []
        out_args = []
        for a in self.args.args:
            #fmt: off
            if a.type.is_pointer() or \
                a.type.is_reference():
                out_args += [a]
            elif isinstance(a.type, cpp_type_container) and (((a.type.is_span() or a.type.is_dynamic_span()) and not a.type.get_contained_type().is_const())):
                out_args += [a]
            else:
                in_args += [a]
            #fmt: on
        return in_args, out_args

    def is_implemented_type(self, type: cpp_type):
        if type.is_const_pointer():
            return False
        return True

    def is_implemented(self):
        #" in a.type.type_name for a in self.args.args):
        #    return False
        #if "GCGLsync" in self.return_type.type_name:
        #    return False
        if any(a.name == "bufSize" for a in self.args.args):
            return False
        if any(a.type.is_pointer() and a.type.get_value_type().is_void() for a in self.args.args):
            return False
        if any(not self.is_implemented_type(a.type) for a in self.args.args):
            return False
        if self.return_type.is_pointer():
            return False
        if not self.is_implemented_type(self.return_type):
            return False
        return True


webkit_ipc_types: Dict[cpp_type, cpp_type] = {}

webkit_ipc_types_converters: Dict[Tuple[cpp_type, cpp_type], CppExprConverter] = {}


def webkit_ipc_convert_expr(expr: cpp_expr, type: cpp_type) -> cpp_expr:
    """ Converts `expr` of type of `self` to `type` """
    convert = webkit_ipc_types_converters.get((expr.type, type), None)
    if not convert:
        if expr.type == type:
            return expr
        convert = cpp_implicit_cast
    return convert(expr, type)


def webkit_ipc_get_span_transfer_type(type : cpp_type_container) -> cpp_type:
    element_type = type.get_contained_type().get_decay_type()
    arity = type.get_arity()
    webkit_ipc_element_type = webkit_ipc_types[element_type] if not element_type.is_void() else get_cpp_type('uint8_t')
    if arity is not None:
        return get_cpp_type(f"IPC::ArrayReference<{str(webkit_ipc_element_type)}, {arity}>")
    return get_cpp_type(f"IPC::ArrayReference<{str(webkit_ipc_element_type)}>")


def webkit_ipc_get_span_store_type(type: cpp_type_container) -> cpp_type:
    element_type = type.get_contained_type().get_decay_type()
    if element_type.is_void():
        element_type = get_cpp_type('GCGLchar')
    if type.is_dynamic_span():
        inline_capacity = 16 if "float" in element_type.type_name else 4
        return get_cpp_type(f"Vector<{str(element_type)}, {str(inline_capacity)}>")
    return get_cpp_type(f"std::array<{str(element_type)}, {str(type.get_arity())}>")

def webkit_ipc_make_gcglspan_conversion(expr : cpp_expr, type : cpp_type_container) -> cpp_expr:
    pointer_cast_type = type.get_contained_type().get_pointer_type()
    if type.is_dynamic_span():
        return cpp_expr(type, f"makeGCGLSpan(reinterpret_cast<{str(pointer_cast_type)}>({str(expr)}.data()), {str(expr)}.size())")

    assert(type.is_span())
    return cpp_expr(type, f"makeGCGLSpan<{str(type.get_arity())}>(reinterpret_cast<{str(pointer_cast_type)}>({str(expr)}.data()))")

# See messages.py function_parameter_type
webkit_ipc_builtin_types = set(
    ["uint8_t", "uint16_t", "uint32_t", "uint64_t", "int8_t", "int16_t", "int32_t", "int64_t", "bool", "float", "double" "bool"]
)


def webkit_ipc_get_message_forwarder_type(type: cpp_type) -> cpp_type:
    if type.type_name in webkit_ipc_builtin_types:
        return type
    return type.get_rvalue_type()


def webkit_ipc_move_expr(expr: cpp_expr) -> cpp_expr:
    if expr.type.type_name in webkit_ipc_builtin_types:
        return expr
    return cpp_move_expr(expr)


def webkit_ipc_msg_name(func: cpp_func):
    return func.name[0].capitalize() + func.name[1:] + func.overload_suffix


class webkit_ipc_msg(object):
    name: str
    in_args: cpp_arg_list
    out_args: cpp_arg_list

    def __init__(self, func: cpp_func):
        self.name = webkit_ipc_msg_name(func)
        in_args, out_args = func.get_args_categories()
        ipc_in_args = [cpp_arg(webkit_ipc_types[a.type], a.name) for a in in_args]
        ipc_out_args = []
        if not func.return_type.is_void():
            ipc_out_args += [cpp_arg(webkit_ipc_types[func.return_type], "returnValue")]
        for a in out_args:
            ipc_out_args += [cpp_arg(webkit_ipc_types[a.type], a.name)]
            if a.type.is_dynamic_span():
                ipc_in_args += [cpp_arg(get_cpp_type("uint64_t"), f"{a.name}Size")]
        self.in_args = cpp_arg_list(ipc_in_args)
        self.out_args = cpp_arg_list(ipc_out_args)

    def __str__(self):
        if len(self.out_args.args):
            return f"\n    void {self.name}({str(self.in_args)}) -> ({str(self.out_args)}) Synchronous"
        return f"\n    void {self.name}({str(self.in_args)})"


class webkit_ipc_cpp_proxy_impl(object):
    name: str
    msg_name: str
    return_type: cpp_type
    args: cpp_arg_list

    pre_call_stmts: List[str]
    call_stmts: List[str]
    post_call_stmts: List[str]
    return_stmts: List[str]
    in_exprs: List[cpp_expr]
    out_exprs: List[cpp_expr]

    def __init__(self, cpp_func: cpp_func):
        self.name = cpp_func.name
        self.msg_name = webkit_ipc_msg_name(cpp_func)
        self.return_type = cpp_func.return_type
        self.args = cpp_func.args
        self.pre_call_stmts = []
        self.call_stmts = []
        self.post_call_stmts = []
        self.return_stmts = []
        self.in_exprs = []
        self.out_exprs = []
        in_args, out_args = cpp_func.get_args_categories()
        self.process_return_value(cpp_func.return_type)
        self.process_in_args(in_args)
        self.process_out_args(out_args)
        self.process_call()

    def process_call(self):
        in_exprs = ", ".join([str(i) for i in self.in_exprs])
        out_exprs = ", ".join(str(o) for o in self.out_exprs)
        is_async = self.return_type.is_void() and len(out_exprs) == 0
        self.call_stmts += [ "if (!isContextLost()) {" ]
        if is_async:
            self.call_stmts += [
                f"    auto sendResult = send(Messages::RemoteGraphicsContextGL::{self.msg_name}({in_exprs}));",
            ]
        else:
            self.call_stmts += [
                f"    auto sendResult = sendSync(Messages::RemoteGraphicsContextGL::{self.msg_name}({in_exprs}), Messages::RemoteGraphicsContextGL::{self.msg_name}::Reply({out_exprs}));"
            ]
        self.call_stmts += [
            "    if (!sendResult)",
            "        markContextLost();",
        ]
        if self.post_call_stmts:
            self.call_stmts += ["    else {"] if len(self.post_call_stmts) > 1 else [ "    else"]
            self.post_call_stmts = [ "    " + l for l in self.post_call_stmts ]
            self.post_call_stmts += [ "    }" ] if len(self.post_call_stmts) > 1 else []
        self.post_call_stmts += [ "}" ]


    def process_in_args(self, in_args: List[cpp_arg]):
        for i in in_args:
            if i.type.is_const_pointer():
                assert False
            else:
                self.in_exprs += [webkit_ipc_convert_expr(cpp_expr(i.type, i.name), webkit_ipc_types[i.type])]

    def process_out_args(self, out_args: List[cpp_arg]):
        for o in out_args:
            if o.type.is_pointer():
                value_type = o.type.get_value_type()
                webkit_ipc_value_type = webkit_ipc_types[value_type]
                v = cpp_arg(webkit_ipc_value_type, o.name + "Reply")
                self.pre_call_stmts += [f"{str(v.type)} {str(v.name)} = {{ }};"]
                e = cpp_expr(v.type, v.name)
                self.out_exprs += [e]
                self.post_call_stmts += [
                    #fmt: off
                    f"    if ({o.name})",
                    f"        *{o.name} = {webkit_ipc_convert_expr(e, value_type)};"
                    #fmt: on
                ]
            elif o.type.is_span():
                webkit_ipc_type = webkit_ipc_types[o.type]
                assert(isinstance(webkit_ipc_type, cpp_type_container))
                v = cpp_arg(webkit_ipc_type, o.name + "Reply")
                self.pre_call_stmts += [f"{str(v.type)} {str(v.name)};"]
                self.out_exprs += [cpp_expr(v.type, v.name)]
                if o.type.is_dynamic_span():
                    self.in_exprs += [cpp_expr(get_cpp_type("size_t"), f"{o.name}.bufSize")]
                self.post_call_stmts += [
                    f"    memcpy({o.name}.data, {v.name}.data(), {o.name}.bufSize * sizeof({str(webkit_ipc_type.get_contained_type())}));"
                ]
            else:
                self.out_exprs += [cpp_expr(o.type, o.name)]

    def process_return_value(self, return_type: cpp_type):
        if return_type.is_void():
            return
        self.return_type = return_type
        ipc_return_type = webkit_ipc_types[return_type]
        return_value_expr = cpp_expr(ipc_return_type, "returnValue")
        self.pre_call_stmts += [f"{return_value_expr.type} {return_value_expr.expr} = {{ }};"]
        self.out_exprs = [return_value_expr] + self.out_exprs
        self.return_stmts = [f"return {str(webkit_ipc_convert_expr(return_value_expr, return_type))};"]

    def __str__(self):
        nolint = " // NOLINT" if "_" in self.name else ""
        body = "".join(f"\n    {b}" for b in self.pre_call_stmts + self.call_stmts + self.post_call_stmts + self.return_stmts)
        return f"""\n{str(self.return_type)} RemoteGraphicsContextGLProxy::{self.name}({str(self.args)}){nolint}
{{{body}
}}"""


class webkit_ipc_cpp_proxy_placeholder(object):
    name: str
    return_type: cpp_type
    args: cpp_arg_list
    body: List[str]

    def __init__(self, cpp_func: cpp_func):
        self.name = cpp_func.name

        self.return_type = cpp_func.return_type
        self.args = cpp_func.args
        self.body = ["notImplemented();"]
        if cpp_func.return_type.type_name != "void":
            self.body += ["return { };"]

    def __str__(self):
        nolint = " // NOLINT" if "_" in self.name else ""
        body = "\n{\n    " + "\n    ".join(self.body) + "\n}"
        return f"\n{str(self.return_type)} RemoteGraphicsContextGLProxy::{self.name}({str(self.args)}){nolint}{body}"


class context_proxy_cpp_webkit_ipc_generator(object):
    "RemoteGraphicsContextGLProxy C++ implementation generator."
    impls: List[webkit_ipc_cpp_proxy_impl]
    unimpls: List[webkit_ipc_cpp_proxy_placeholder]

    def __init__(self, funcs: Iterable[cpp_func], unimplemented: Iterable[cpp_func]):
        self.impls = [webkit_ipc_cpp_proxy_impl(f) for f in funcs]
        self.unimpls = [webkit_ipc_cpp_proxy_placeholder(f) for f in unimplemented]

    def get_functions(self):
        return "\n".join(str(i) for i in self.impls + self.unimpls)

    def generate(self):
        write_file(
            context_proxy_functions_fn,
            context_proxy_functions_template.format(self.get_functions()),
        )


class webkit_ipc_cpp_impl(object):
    name: str
    args: cpp_arg_list
    is_extension: bool
    pre_call_stmts: List[str]
    call_stmts: List[str]
    post_call_stmts: List[str]
    in_exprs: List[cpp_expr]
    out_exprs: List[cpp_expr]
    return_value_expr: Optional[cpp_expr]

    def __init__(self, cpp_func: cpp_func):
        self.name = cpp_func.name
        self.overload_suffix = cpp_func.overload_suffix
        self.args = cpp_arg_list([])
        self.is_extension = cpp_func.is_extension
        self.pre_call_stmts = []
        self.call_stmts = []
        self.post_call_stmts = []
        self.in_exprs = []
        self.out_exprs = []
        self.return_value_expr = None

        self.process_return_value(cpp_func.return_type)
        in_args, out_args = cpp_func.get_args_categories()
        self.process_args(cpp_func.args.args, set(in_args), set(out_args))
        self.process_call()

    def process_call(self):
        self.call_stmts += [ "assertIsCurrent(m_streamThread);" ]
        ext = "getExtensions()." if self.is_extension else ""

        in_exprs = ", ".join(str(e) for e in self.in_exprs)
        is_async = len(self.out_exprs) == 0

        call_expr = f"m_context->{ext}{self.name}({in_exprs})"
        if not self.return_value_expr:
            self.call_stmts += [f"{call_expr};"]
        else:
            self.call_stmts += [f"{str(self.return_value_expr)} = {call_expr};"]
        if not is_async:
            out_exprs = ", ".join(str(e) for e in self.out_exprs)
            self.post_call_stmts += [f"completionHandler({out_exprs});"]

    def process_args(self, args: List[cpp_arg], in_args: Set[cpp_arg], out_args: Set[cpp_arg]):
        for a in args:
            if a.type.is_const_pointer():
                assert False
            if a in in_args:
                self.process_in_arg(a)
            else:
                self.process_out_arg(a)
        if self.out_exprs:
            out_arg_decls = ", ".join(f"{str(e.type)}" for e in self.out_exprs)
            self.args.args += [cpp_arg(get_cpp_type(f"CompletionHandler<void({out_arg_decls})>&&"), "completionHandler")]

    def process_in_arg(self, a: cpp_arg):
        self.args.args += [cpp_arg(webkit_ipc_get_message_forwarder_type(webkit_ipc_types[a.type]), a.name)]
        self.in_exprs += [webkit_ipc_convert_expr(cpp_expr(webkit_ipc_types[a.type], a.name), a.type)]

    def process_out_arg(self, a: cpp_arg):
        if a.type.is_pointer():
            value_arg = cpp_arg(a.type.get_value_type(), a.name)
            self.pre_call_stmts += [f"{str(value_arg.type)} {str(value_arg.name)} = {{ }};"]
            self.in_exprs += [cpp_expr(a.type, f"&{value_arg.name}")]
            e = cpp_expr(value_arg.type, value_arg.name)
            webkit_ipc_value_type = webkit_ipc_types[e.type]
            self.out_exprs += [webkit_ipc_convert_expr(e, webkit_ipc_value_type)]
        elif a.type.is_dynamic_span():
            assert(isinstance(a.type, cpp_type_container))
            size_arg = cpp_arg(get_cpp_type("uint64_t"), f"{a.name}Size")
            self.args.args += [size_arg]
            store_arg = cpp_arg(webkit_ipc_get_span_store_type(a.type), a.name)
            self.pre_call_stmts += [f"{str(store_arg.type)} {str(store_arg.name)}(static_cast<size_t>({a.name}Size), 0);"]
            self.in_exprs += [cpp_expr(store_arg.type, f"{store_arg.name}")]
            webkit_ipc_type = webkit_ipc_types[a.type]
            self.out_exprs += [webkit_ipc_convert_expr(cpp_expr(store_arg.type, store_arg.name), webkit_ipc_type)]
        elif a.type.is_span():
            assert(isinstance(a.type, cpp_type_container))
            store_arg = cpp_arg(webkit_ipc_get_span_store_type(a.type), a.name)
            self.pre_call_stmts += [f"{str(store_arg.type)} {str(store_arg.name)} {{ }};"]
            self.in_exprs += [cpp_expr(store_arg.type, store_arg.name)]
            webkit_ipc_type = webkit_ipc_types[a.type]
            self.out_exprs += [webkit_ipc_convert_expr(cpp_expr(store_arg.type, store_arg.name), webkit_ipc_type)]
        else:
            assert a.type.is_reference()
            webkit_ipc_type = webkit_ipc_types[a.type]
            value_arg = cpp_arg(a.type.get_value_type(), a.name)
            self.pre_call_stmts += [f"{self.ns(value_arg.type)} {str(value_arg.name)} {{ }};"]
            e = cpp_expr(value_arg.type, value_arg.name)
            self.in_exprs += [e]
            self.out_exprs += [webkit_ipc_move_expr(webkit_ipc_convert_expr(e, webkit_ipc_type))]

    def process_return_value(self, return_type: cpp_type):
        if return_type.is_void():
            return
        ipc_return_type = webkit_ipc_types[return_type]
        return_value_expr = cpp_expr(return_type, "returnValue")
        self.pre_call_stmts += [f"{return_value_expr.type} {return_value_expr.expr} = {{ }};"]
        self.out_exprs += [webkit_ipc_move_expr(webkit_ipc_convert_expr(return_value_expr, ipc_return_type))]
        self.return_value_expr = return_value_expr

    def __str__(self):
        body = "".join(f"\n        {b}" for b in self.pre_call_stmts + self.call_stmts + self.post_call_stmts)
        return f"""    void {self.name}{self.overload_suffix}({str(self.args)})
    {{{body}
    }}"""

    def ns(self, type: cpp_type):
        # TODO: namespace info is not stored in names.
        if type.type_name == "ActiveInfo":
            return "WebCore::GraphicsContextGL::" + str(type)
        return str(type)

def webkit_ipc_resolve_overload_suffix(funcs : Iterable[cpp_func]):
    counts = collections.Counter(f.name for f in funcs)
    suffixes : Counter[str] = collections.Counter()
    for f in funcs:
        if counts[f.name] > 1:
            f.overload_suffix = str(suffixes[f.name])
            suffixes.update([f.name])


class context_cpp_webkit_ipc_generator(object):
    "RemoteGraphicsContextGL C++ implementation generator."
    impls: List[webkit_ipc_cpp_impl]

    def __init__(self, funcs: Iterable[cpp_func]):
        self.impls = [webkit_ipc_cpp_impl(f) for f in funcs]

    def get_functions(self):
        return "\n".join(str(i) for i in self.impls)

    def generate(self):
        write_file(
            context_functions_fn,
            context_functions_template.format(self.get_functions()),
        )


class context_msg_webkit_ipc_generator(object):
    "RemoteGraphicsContextGL WebKit IPC message definition generator."
    msgs: List[webkit_ipc_msg]

    def __init__(self, funcs: Iterable[cpp_func]):
        self.msgs = [webkit_ipc_msg(f) for f in funcs]

    def get_messages(self):
        return "".join(str(m) for m in self.msgs)

    def generate(self):
        write_file(context_messages_fn, context_messages_template.format(self.get_messages()))


def create_cpp_arg(arg_spec: str, arg_index: int):
    r = arg_spec.rsplit(" ", 1)
    name = ""
    type = None
    if len(r) > 1 and r[0] != "const":
        name = r[1].strip()
        type = get_cpp_type(r[0])
    else:
        name = "arg{}".format(arg_index)
        type = get_cpp_type(arg_spec)
    return cpp_arg(type, name)


def create_cpp_arg_list(args_specs: Iterable[str]):
    return cpp_arg_list([create_cpp_arg(arg_spec=e, arg_index=i) for i, e in enumerate(args_specs)])


def create_cpp_func(name: str, return_spec: str, args_specs: List[str], is_extension: bool):
    return cpp_func(name=name, return_type=get_cpp_type(return_spec), args=create_cpp_arg_list(args_specs), is_extension=is_extension)


def read_lines_until(lines : Iterable[str], match : str) -> Generator[str, None, None]:
    for line in lines:
        if re.match(match, line.strip()):
            break
        yield line

def main():
    parser = argparse.ArgumentParser("usage: %prog [options]")
    parser.add_argument("--verbose", action="store_true", help="Print some debug info from the generator script")
    options = parser.parse_args()

    # Construct the list of functions to remote from web process to GPU process.

    # FIXME: Until extensions header is removed, we need to complicate the implementation
    # with the distinction of whether a function is or is not an extension function.
    extension_signatures : Set[str] = set()
    with open(extensions_input_fn) as f:
        for line in f.readlines():
            m = re.match(r".*virtual (\S+)\s+(\w+)\((.*)\) = 0;", line)
            if m:
                func = create_cpp_func(
                    name=m[2],
                    return_spec=m[1],
                    args_specs=cpp_split_args_specs(m[3]),
                    is_extension=True,
                )
                extension_signatures.update([str(func)])
    funcs = []
    unimplemented = []
    for fn in functions_input_fns:
        with open(fn) as f:
            lines = iter(f.readlines())
            for _ in read_lines_until(lines, "// Functions with a generated implementation. This list is used by generate-gpup-webgl script."):
                pass

            for line in read_lines_until(lines, "// End of list used by generate-gpup-webgl script."):
                m = re.match(r"\s*(\S+)\s+(\w+)\((.*)\) final;", line)
                if m:
                    func_name = m[2]
                    func = create_cpp_func(
                        name=func_name,
                        return_spec=m[1],
                        args_specs=cpp_split_args_specs(m[3]),
                        is_extension=False,
                    )
                    func.is_extension = str(func) in extension_signatures
                    if func.is_implemented():
                        funcs.append(func)
                    else:
                        unimplemented.append(func)


    webkit_ipc_resolve_overload_suffix(funcs)
    # Initialize WebKit IPC generation. Construct type mappings for the used C++ types -> IPC types.
    # TODO: namespacing issues.
    ai_type = get_cpp_type("ActiveInfo&")
    ai_transfer_type = get_cpp_type("WebCore::GraphicsContextGL::ActiveInfo")
    webkit_ipc_types[ai_type] = ai_transfer_type

    with open(types_input_fn) as f:
        lines = iter(f.readlines())
        for _ in read_lines_until(lines, "// The GCGL types map to following WebKit IPC types. The list is used by generate-gpup-webgl script."):
            pass
        for line in read_lines_until(lines, "// End of list used by generate-gpup-webgl script."):
            m = re.match(r".*static_assert\(std::is_same_v<(\w+), (\w+)>\);", line)
            if m:
                webkit_ipc_types[get_cpp_type(m[1])] = get_cpp_type(m[2])
                continue
            m = re.match(r".*static_assert\(sizeof\((\w+)\) == sizeof\((\w+)\)\);", line)
            if m:
                cpp_type = get_cpp_type(m[1])
                ipc_type = get_cpp_type(m[2])
                webkit_ipc_types[cpp_type] = ipc_type
                webkit_ipc_types_converters[(cpp_type, ipc_type)] = cpp_static_cast
                webkit_ipc_types_converters[(ipc_type, cpp_type)] = cpp_static_cast
                continue
            # FIXME: Here we use <= instead of == due to pointers, such as GCGLsync, GCGLintptr, ....
            # This ends up failing if there ever is arrays of these types, since arrays are currently
            # reinterpret-casted.
            # WebKit IPC requires one sized type, but the size of these pointer-based values will change
            # based on the platform.
            m = re.match(r".*static_assert\(sizeof\((\w+)\) <= sizeof\((\w+)\)\);", line)
            if m:
                cpp_type = get_cpp_type(m[1])
                ipc_type = get_cpp_type(m[2])
                webkit_ipc_types[cpp_type] = ipc_type
                webkit_ipc_types_converters[(cpp_type, ipc_type)] = cpp_static_cast
                webkit_ipc_types_converters[(ipc_type, cpp_type)] = cpp_static_cast
                continue
            m = re.match(r".*static_assert\(sizeof\((\w+)\) <= sizeof\((\w+)\) && sizeof\((\w+)\) == sizeof\((\w+)\)\);", line)
            if m:
                cpp_type = get_cpp_type(m[1])
                ipc_type = get_cpp_type(m[2])
                cpp_cast_through_type = get_cpp_type(m[4])
                webkit_ipc_types[cpp_type] = ipc_type
                webkit_ipc_types_converters[(cpp_type, ipc_type)] = cpp_reinterpret_cast_from_pointer_through(cpp_cast_through_type)
                webkit_ipc_types_converters[(ipc_type, cpp_type)] = cpp_reinterpret_cast_to_pointer_through(cpp_cast_through_type)
                continue

    # For all types in the input API, form corresponding IPC types and conversions.
    # TODO: this is not driven by the typing.
    all_types = set()
    for func in funcs:
       all_types.update(func.args.types() + [func.return_type])
    # Sort by len so that template args come before templates.
    for cpp_type in sorted(all_types, key=lambda x: len(x.type_name)):
        if cpp_type in webkit_ipc_types:
            continue

        if cpp_type.is_dynamic_span() or cpp_type.is_span():
            transfer_type = webkit_ipc_get_span_transfer_type(cpp_type)
            webkit_ipc_types[cpp_type] = transfer_type.get_value_type()
            if cpp_type.get_contained_type().is_const():
                webkit_ipc_types_converters[(cpp_type, transfer_type)] = webkit_ipc_span_transfer_type_reinterpret_cast_conversion
                webkit_ipc_types_converters[(transfer_type, cpp_type)] = webkit_ipc_make_gcglspan_conversion
            else:
                store_type = webkit_ipc_get_span_store_type(cpp_type)
                webkit_ipc_types_converters[(store_type, transfer_type)] = cpp_array_reinterpret_cast_conversion
        elif cpp_type.is_reference() or cpp_type.is_const_reference() or cpp_type.is_container():
            value_type = cpp_type.get_value_type() if not cpp_type.is_container() else cpp_type
            if value_type.is_container():
                contained_type = value_type.get_contained_type()
                webkit_ipc_contained_type = webkit_ipc_types[contained_type]
                if webkit_ipc_contained_type == contained_type:
                    webkit_ipc_types[cpp_type] = value_type
                else:
                    transfer_type = get_cpp_type(f"{value_type.get_container_name()}<{str(webkit_ipc_contained_type)}>")
                    webkit_ipc_types[cpp_type] = transfer_type
                    # TODO: Here might be case where Vector<GCGLint> was used in the interface and Vector<int32_t> is used
                    # in the IPC definition. There is no sensible way to do this at the moment. We do not convert, rather
                    # expect that all the invocations are taken care of the fact that GCGLint is the same type as int32_t.
                    # This will not hold for all types such as GCGLboolean.
                    #webkit_ipc_types_converters[(cpp_type, transfer_type)] = cpp_array_reinterpret_cast_conversion
            else:
                webkit_ipc_types[cpp_type] = value_type
        else:
            webkit_ipc_types[cpp_type] = cpp_type.get_value_type()

    # The input to the generators is list of functions to remote.
    # Run the various generators.
    generators = [
        context_proxy_cpp_webkit_ipc_generator(funcs, unimplemented),
        context_msg_webkit_ipc_generator(funcs),
        context_cpp_webkit_ipc_generator(funcs),
    ]
    for g in generators:
        g.generate()

    if options.verbose:
        print("Implemented:")
        print("".join(f"    {str(i)} final\n" for i in funcs))
        print("Unimplemented:")
        print("".join(f"    {str(u)} final\n" for u in unimplemented))
        print(f"Implemented: {len(funcs)}, unimplemented: {len(unimplemented)}, total: {len(funcs)+len(unimplemented)}")
        print("C++ type map to WebKit IPC type map:")
        for _, t in cpp_types.items():
            if t in webkit_ipc_types:
                print(f"    {str(t)} -> {str(webkit_ipc_types[t])}")
        print("C++ types without WebKit IPC type:")
        for _, t in cpp_types.items():
            if t not in webkit_ipc_types:
                print(f"    {str(t)}")
        print("WebKit IPC type conversions")
        for (a, b), converter in webkit_ipc_types_converters.items():
            print(f"    {str(a)} -> {str(b)} : {converter.__name__}")
        print("Done.")
    return 0


if __name__ == "__main__":
    sys.exit(main())