/*
 *  Copyright (C) 2016 Charybdis Development Team
 *  Copyright (C) 2016 Jason Volk <jason@zemos.net>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice is present in all copies.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

#include <ircd/js/js.h>
#include <js/Initialization.h>
#include <mozilla/ThreadLocal.h>
#include "/home/jason/charybdis/charybdis/gecko-dev/js/src/vm/Opcodes.h"

namespace ircd {
namespace js   {

decltype(xdr::bytecode::info) xdr::bytecode::info
{
	0
};

} // namespace js
} // namespace ircd

ircd::js::xdr::xdr(const uint8_t *const &buf,
                   const size_t &len)
:header
{
	reinterpret_cast<const struct header *>(buf)
}
,name
{
	reinterpret_cast<const struct atom *>(buf + sizeof(*header))
}
,binding{[this]
{
	const auto *ret(reinterpret_cast<const uint8_t *>(this->name));
	for_each_name([&ret](const struct atom &atom)
	{
		ret += sizeof(struct atom) + atom.length;
	});

	return reinterpret_cast<const struct binding *>(ret);
}()}
,sourcecode{[this]
{
	const auto bindings(header->num_bindings());
	const auto *ptr(reinterpret_cast<const uint8_t *>(this->binding + bindings));
	return reinterpret_cast<const struct sourcecode *>(ptr);
}()}
,sourcemap{[this]
{
	const auto *ptr(reinterpret_cast<const uint8_t *>(this->sourcecode + 1) + this->sourcecode->compressed_length);
	return reinterpret_cast<const struct sourcemap *>(ptr);
}()}
,displayurl{[this]
{
	if(!this->sourcemap->have)
	{
		const auto ptr(reinterpret_cast<const uint8_t *>(this->sourcemap) + 1);
		return reinterpret_cast<const struct displayurl *>(ptr);
	}

	const auto ptr(reinterpret_cast<const uint8_t *>(this->sourcemap + 1) + this->sourcemap->len);
	return reinterpret_cast<const struct displayurl *>(ptr);
}()}
,filename{[this]
{
	if(!this->displayurl->have)
	{
		const auto ptr(reinterpret_cast<const uint8_t *>(this->displayurl) + 1);
		return reinterpret_cast<const struct filename *>(ptr);
	}

	const auto ptr(reinterpret_cast<const uint8_t *>(this->displayurl + 1) + this->displayurl->len);
	return reinterpret_cast<const struct filename *>(ptr);
}()}
,source{[this]
{
	if(!this->filename->have)
	{
		const auto ptr(reinterpret_cast<const uint8_t *>(this->filename) + 1);
		return reinterpret_cast<const struct source *>(ptr);
	}

	const auto ptr(reinterpret_cast<const uint8_t *>(this->filename + 1) + strlen(this->filename->name) + 1);
	return reinterpret_cast<const struct source *>(ptr);
}()}
,bytecode{[this]
{
	const auto ptr(reinterpret_cast<const uint8_t *>(this->source + 1));
	return reinterpret_cast<const struct bytecode *>(ptr);
}()}
,srcnote{[this]
{
	const auto ptr(reinterpret_cast<const uint8_t *>(this->bytecode + this->header->length));
	return reinterpret_cast<const struct srcnote *>(ptr);
}()}
,atom{[this]
{
	const auto ptr(reinterpret_cast<const uint8_t *>(this->srcnote + this->header->n_srcnotes));
	return reinterpret_cast<const struct atom *>(ptr);
}()}
,consts{[this]
{
	const auto *ptr(reinterpret_cast<const uint8_t *>(this->atom));
	for_each_atom([&ptr](const struct atom &atom)
	{
		ptr += sizeof(struct atom) + atom.length;
	});

	return reinterpret_cast<const struct consts *>(ptr);
}()}
,object{[this]
{
	const auto *ptr(reinterpret_cast<const uint8_t *>(this->consts));
	for_each_const([&ptr](const struct consts &c)
	{
		ptr += length(c);
	});

	return reinterpret_cast<const struct object *>(ptr);
}()}
{
}

void
ircd::js::xdr::for_each_object(const std::function<void (const struct object &)> &cb)
const
{
	auto object(this->object);
	const auto *ptr(reinterpret_cast<const uint8_t *>(object));
	for(size_t i(0); i < header->n_objects; i++)
	{
		cb(*object);
		ptr += length(*object);
		object = reinterpret_cast<const struct object *>(ptr);
	}
}

void
ircd::js::xdr::for_each_const(const std::function<void (const struct consts &)> &cb)
const
{
	auto consts(this->consts);
	const auto *ptr(reinterpret_cast<const uint8_t *>(this->consts));
	for(size_t i(0); i< header->n_consts; i++)
	{
		cb(*consts);
		ptr += length(*consts);
		consts = reinterpret_cast<const struct consts *>(ptr);
	}
}

void
ircd::js::xdr::for_each_bytecode(const std::function<void (const struct bytecode &)> &cb)
const
{
	const uint8_t *const start(reinterpret_cast<const uint8_t *>(bytecode));
	const uint8_t *ptr(reinterpret_cast<const uint8_t *>(bytecode));
	for(; ptr < start + header->length;)
	{
		const auto &bytecode(*reinterpret_cast<const struct bytecode *>(ptr));
		ptr += info(bytecode).length;
		cb(bytecode);
	}
}

void
ircd::js::xdr::for_each_binding(const std::function<void (const struct binding &)> &cb)
const
{
	const auto *binding(this->binding);
	const size_t bindings(header->num_names());
	for(; binding < this->binding + bindings; ++binding)
		cb(*binding);
}

void
ircd::js::xdr::for_each_name(const std::function<void (const struct atom &)> &cb)
const
{
	const uint8_t *ptr(reinterpret_cast<const uint8_t *>(name));
	const auto names(header->num_names());
	for(size_t i(0); i < names; ++i)
	{
		const auto atom(reinterpret_cast<const struct atom *>(ptr));
		cb(*atom);
        ptr += sizeof(struct atom) + atom->length;
    }
}

void
ircd::js::xdr::for_each_atom(const std::function<void (const struct atom &)> &cb)
const
{
	const uint8_t *ptr(reinterpret_cast<const uint8_t *>(atom));
	for(size_t i(0); i < header->n_atoms; ++i)
	{
		const auto atom(reinterpret_cast<const struct atom *>(ptr));
		cb(*atom);
        ptr += sizeof(struct atom) + atom->length;
    }
}

size_t
ircd::js::xdr::header::num_bindings()
const
{
	return num_names();
}

size_t
ircd::js::xdr::header::num_names()
const
{
	return n_args + n_vars + n_body_level_lexicals;
}


size_t
ircd::js::length(const struct xdr::consts &consts)
{
	switch(consts.tag)
	{
		case 0:   return 4 + 4;         // ::js::SCRIPT_INT
		case 1:   return 4 + 8;         // ::js::SCRIPT_DOUBLE
		case 2:                         // ::js::SCRIPT_ATOM
			return 4 + 4;
			//return 4 + 4 + consts.atom.length;

		case 3:   return 4 + 0;         // ::js::SCRIPT_TRUE
		case 4:   return 4 + 0;         // ::js::SCRIPT_FALSE
		case 5:   return 4 + 0;         // ::js::SCRIPT_NULL
		case 6:                         // ::js::SCRIPT_OBJECT
			throw error("unsupported consts (object)");

		case 7:   return 4 + 0;         // ::js::SCRIPT_VOID
		case 8:   return 4 + 0;         // ::js::SCRIPT_HOLE

		default:
			throw error("unsupported consts tag [%u]", consts.tag);
	}
}

size_t
ircd::js::length(const struct xdr::object &object)
{
	switch(object.classk)
	{
		case 0:     return 4 + length(object.block);
		case 1:     return 4 + length(object.with);
		case 2:     return 4 + length(object.function);
		case 3:     return 4 + length(object.literal);
		default:
			throw error("unsupported object class kind [%u]", object.classk);
	}
}

size_t
ircd::js::length(const struct xdr::object::literal &literal)
{
	size_t ret(0);
	const auto *ptr(reinterpret_cast<const uint8_t *>(&literal) + 8);
	for(size_t i(0); i < literal.n_properties; ++i)
	{
		const auto prop(reinterpret_cast<const struct xdr::consts *>(ptr + ret));
		printf("i[%zu] atom [%u] length [%u]\n", i, prop->u32, prop->atom.length);
		const auto len(length(*prop));
		ret += 8;
	}

	return 8 + ret;
}

size_t
ircd::js::length(const struct xdr::object::function &function)
{
	return 12;
}

size_t
ircd::js::length(const struct xdr::object::with &with)
{
	return 0;
}

size_t
ircd::js::length(const struct xdr::object::block &block)
{
	return 0;
}

__attribute__((constructor))
void
init_opcodes()
{
	using xdr = ircd::js::xdr;

	#define IRCD_JS_INIT_OP(code, value, name, image, len, nuses, ndefs, format) \
		xdr::bytecode::info[value] = { name, uint8_t(len), uint8_t(ndefs), uint8_t(nuses) };

    static const auto js_undefined_str("");
    static const auto js_false_str("false");
    static const auto js_true_str("false");
    static const auto js_void_str("void");
    static const auto js_null_str("null");
    static const auto js_throw_str("throw");
    static const auto js_in_str("in");
    static const auto js_instanceof_str("instanceOf");
    static const auto js_typeof_str("typeOf");

	FOR_EACH_OPCODE(IRCD_JS_INIT_OP);
}