/* $Id$ */

/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file scope_info.h Scope info debug functions. */

#ifndef SCOPE_INFO_H
#define SCOPE_INFO_H

#include "tile_type.h"

#include <functional>
#include <vector>

struct Vehicle;
struct BaseStation;

#ifdef USE_SCOPE_INFO

extern std::vector<std::function<int(char *, const char *)>> _scope_stack;

struct scope_info_func_obj {
	scope_info_func_obj(std::function<int(char *, const char *)> func)
	{
		_scope_stack.emplace_back(std::move(func));
	}

	scope_info_func_obj(const scope_info_func_obj &copysrc) = delete;

	~scope_info_func_obj()
	{
		_scope_stack.pop_back();
	}
};

int WriteScopeLog(char *buf, const char *last);

#define SCOPE_INFO_PASTE(a, b) a ## b

/**
 * This creates a lambda in the current scope with the specified capture which outputs the given args as a format string.
 * This lambda is then captured by reference in a std::function which is pushed onto the scope stack
 * The scope stack is popped at the end of the scope
 */
#define SCOPE_INFO_FMT(capture, ...) \
	auto SCOPE_INFO_PASTE(_sc_lm_, __LINE__) = capture (char *buf, const char *last) { \
		return seprintf(buf, last, __VA_ARGS__); \
	}; \
	scope_info_func_obj SCOPE_INFO_PASTE(_sc_obj_, __LINE__) ([&](char *buf, const char *last) -> int { \
		return SCOPE_INFO_PASTE(_sc_lm_, __LINE__) (buf, last); \
	});

#else /* USE_SCOPE_INFO */

#define SCOPE_INFO_FMT(...) { }

#endif /* USE_SCOPE_INFO */

/**
 * This is a set of helper functions to print useful info from within a SCOPE_INFO_FMT statement.
 * The use of a struct is so that when used as an argument to SCOPE_INFO_FMT/seprintf/etc, the buffer lives
 * on the stack with a lifetime which lasts until the end of the statement.
 * This avoids needing to call malloc(), which is technically unsafe within the crash logger signal handler,
 * writing directly into the seprintf buffer, or the use of a separate static buffer.
 */
struct scope_dumper {
	const char *CompanyInfo(int company_id);
	const char *VehicleInfo(const Vehicle *v);
	const char *StationInfo(const BaseStation *st);
	const char *TileInfo(TileIndex tile);

private:
	char buffer[512];
};

#endif /* SCOPE_INFO_H */
