/* $Id$ */

/** @file ai_town.hpp Everything to query towns */

#ifndef AI_TOWN_HPP
#define AI_TOWN_HPP

#include "ai_object.hpp"

/**
 * Class that handles all town related functions.
 */
class AITown : public AIObject {
public:
	/**
	 * Gets the maximum town index; there are no valid towns with a higher index.
	 * @return the maximum town index.
	 * @post return value is always non-negative.
	 */
	TownID GetMaxTownID();

	/**
	 * Gets the number of towns. This is different than GetMaxTownID()
	 *   because of the way OpenTTD works internally.
	 * @return the number of towns.
	 * @post return value is always non-negative.
	 */
	int32 GetTownCount();

	/**
	 * Checks whether the given town index is valid.
	 * @param town_id the index to check.
	 * @return true if and only if the town is valid.
	 */
	static bool IsValidTown(TownID town_id);

	/**
	 * Get the name of the town.
	 * @param town_id the town to get the name of.
	 * @pre town_id has to be valid (use IsValidTown()).
	 * @return the name of the town.
	 * @note the returned name must be free'd (C++ only).
	 */
	char *GetName(TownID town_id);

	/**
	 * Gets the number of inhabitants in the town.
	 * @param town_id the town to get the name of.
	 * @pre town_id has to be valid (use IsValidTown()).
	 * @return the number of inhabitants.
	 * @post return value is always non-negative.
	 */
	int32 GetPopulation(TownID town_id);

	/**
	 * Gets the location of the town.
	 * @param town_id the location of the town.
	 * @pre town_id has to be valid (use IsValidTown()).
	 * @return the location of the town.
	 * @post return value is always positive and below AIMap::GetMapSize().
	 */
	TileIndex GetLocation(TownID town_id);
};

#ifdef DEFINE_SQUIRREL_CLASS
namespace SQConvert {
	/* Allow AITown to be used as Squirrel parameter */
	template <> AITown *GetParam(ForceType<AITown *>, HSQUIRRELVM vm, int index) { SQUserPointer instance; sq_getinstanceup(vm, index, &instance, 0); return (AITown *)instance; }
}; // namespace SQConvert

void SQAITownRegister(Squirrel *engine) {
	DefSQClass <AITown> SQAITown("AITown");
	SQAITown.PreRegister(engine);
	SQAITown.AddConstructor(engine);
	SQAITown.DefSQFunction(engine, &AITown::GetMaxTownID,  "GetMaxTownID");
	SQAITown.DefSQFunction(engine, &AITown::GetTownCount,  "GetTownCount");
	SQAITown.DefSQFunction(engine, &AITown::IsValidTown,   "IsValidTown");
	SQAITown.DefSQFunction(engine, &AITown::GetName,       "GetName");
	SQAITown.DefSQFunction(engine, &AITown::GetPopulation, "GetPopulation");
	SQAITown.DefSQFunction(engine, &AITown::GetLocation,   "GetLocation");
	SQAITown.PostRegister(engine);
}
#endif /* DEFINE_SQUIRREL_CLASS */

#endif /* AI_TOWN_HPP */