/*
 * LuaTables++
 * Copyright (c) 2013-2014 Martin Felis <martin@fyxs.org>.
 * All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef LUATABLES_H
#define LUATABLES_H

#include <iostream>
#include <assert.h>
#include <cstdlib>
#include <string>
#include <vector>

#include <rbdl/rbdl_config.h>

// Forward declaration for Lua
extern "C" {
struct lua_State;
}

struct RBDL_DLLAPI LuaKey {
	enum Type {
		String,
		Integer
	};

	Type type;
	int int_value;
	std::string string_value;

	bool operator<( const LuaKey& rhs ) const {
		if (type == String && rhs.type == Integer) {
			return false;
		} else if (type == Integer && rhs.type == String) {
			return true;
		} else if (type == Integer && rhs.type == Integer) {
			return int_value < rhs.int_value;
		}

		return string_value < rhs.string_value;
	}

	LuaKey (const char* key_value) :
		type (String),
		int_value (0),
		string_value (key_value) { }
	LuaKey (int key_value) :
		type (Integer),
		int_value (key_value),
		string_value ("") {}
};

inline std::ostream& operator<<(std::ostream& output, const LuaKey &key) {
	if (key.type == LuaKey::Integer)
		output << key.int_value << "(int)";
	else
		output << key.string_value << "(string)";
	return output;
}
struct RBDL_DLLAPI LuaTable;
struct RBDL_DLLAPI LuaTableNode;

struct RBDL_DLLAPI LuaTableNode {
	LuaTableNode() :
		parent (NULL),
		luaTable (NULL),
		key("")
	{ }
	LuaTableNode operator[](const char *child_str) {
		LuaTableNode child_node;

		child_node.luaTable = luaTable;
		child_node.parent = this;
		child_node.key = LuaKey (child_str);

		return child_node;
	}
	LuaTableNode operator[](int child_index) {
		LuaTableNode child_node;

		child_node.luaTable = luaTable;
		child_node.parent = this;
		child_node.key = LuaKey (child_index);

		return child_node;
	}
	bool stackQueryValue();
	void stackPushKey();
	void stackCreateValue();
	void stackRestore();
	LuaTable stackQueryTable();
	LuaTable stackCreateLuaTable();

	std::vector<LuaKey> getKeyStack();
	std::string keyStackToString();

	bool exists();
	void remove();
	size_t length();
	std::vector<LuaKey> keys();

	// Templates for setters and getters. Can be specialized for custom
	// types.
	template <typename T>
	void set (const T &value);
	template <typename T>
	T getDefault (const T &default_value);

	template <typename T>
	T get() {
		if (!exists()) {
			std::cerr << "Error: could not find value " << keyStackToString() << "." << std::endl;
			abort();
		}
		return getDefault (T());
	}

	// convenience operators (assignment, conversion, comparison)
	template <typename T>
	void operator=(const T &value) {
		set<T>(value);
	}
	template <typename T>
	operator T() {
		return get<T>();
	}
	template <typename T>
	bool operator==(T value) {
		return value == get<T>();
	}
	template <typename T>
	bool operator!=(T value) {
		return value != get<T>();
	}

	LuaTableNode *parent;
	LuaTable *luaTable;
	LuaKey key;
	int stackTop;
};

template<typename T>
bool operator==(T value, LuaTableNode node) {
	return value == (T) node;
}
template<typename T>
bool operator!=(T value, LuaTableNode node) {
	return value != (T) node;
}

template<> bool LuaTableNode::getDefault<bool>(const bool &default_value);
template<> double LuaTableNode::getDefault<double>(const double &default_value);
template<> float LuaTableNode::getDefault<float>(const float &default_value);
template<> std::string LuaTableNode::getDefault<std::string>(const std::string &default_value);

template<> void LuaTableNode::set<bool>(const bool &value);
template<> void LuaTableNode::set<float>(const float &value);
template<> void LuaTableNode::set<double>(const double &value);
template<> void LuaTableNode::set<std::string>(const std::string &value);

/// Reference counting Lua state
struct RBDL_DLLAPI LuaStateRef {
	LuaStateRef () :
		L (NULL),
		count (0),
		freeOnZeroRefs(true)
	{}

	LuaStateRef* acquire() {
		count = count + 1;
		return this;
	}

	int release() {
		count = count - 1;
		return count;
	}

	lua_State *L;
	unsigned int count;
	bool freeOnZeroRefs;
};

struct RBDL_DLLAPI LuaTable {
	LuaTable () :
		filename (""),
		luaStateRef (NULL),
		luaRef(-1),
		L (NULL),
		referencesGlobal (false)
	{}
	LuaTable (const LuaTable &other);
	LuaTable& operator= (const LuaTable &other);
	~LuaTable();

	LuaTableNode operator[] (const char* key) {
		LuaTableNode root_node;
		root_node.key = LuaKey (key);
		root_node.parent = NULL;
		root_node.luaTable = this;

		return root_node;
	}
	LuaTableNode operator[] (int key) {
		LuaTableNode root_node;
		root_node.key = LuaKey (key);
		root_node.parent = NULL;
		root_node.luaTable = this;

		return root_node;
	}
	int length();
	void addSearchPath (const char* path);
	std::string serialize ();

	/// Serializes the data in a predictable ordering.
	std::string orderedSerialize ();

	/// Pushes the Lua table onto the stack of the internal Lua state.
	//  I.e. makes the Lua table active that is associated with this
	//  LuaTable.
	void pushRef();
	/// Pops the Lua table from the stack of the internal Lua state.
	//  Cleans up a previous pushRef()
	void popRef();

	static LuaTable fromFile (const char *_filename);
	static LuaTable fromLuaExpression (const char* lua_expr);
	static LuaTable fromLuaState (lua_State *L);

	std::string filename;
	LuaStateRef *luaStateRef;
	int luaRef;
	lua_State *L;

	bool referencesGlobal;
};

/* LUATABLES_H */
#endif