/* $Id$ */

/** @file ai_tile.cpp Implementation of AITile. */

#include "ai_tile.hpp"
#include "ai_map.hpp"
#include "ai_town.hpp"
#include "../../openttd.h"
#include "../../tile_map.h"
#include "../../map_func.h"
#include "../../variables.h"
#include "../../station_func.h"
#include "../../command_type.h"
#include "../../settings_type.h"
#include "../../player_func.h"
#include "../../road_map.h"

/* static */ bool AITile::IsBuildable(TileIndex tile)
{
	if (!::IsValidTile(tile)) return false;

	switch (::GetTileType(tile)) {
		default: return false;
		case MP_CLEAR: return true;
		case MP_ROAD:
			/* Depots aren't considered buildable */
			if (::GetRoadTileType(tile) == ROAD_TILE_DEPOT) return false;
			if (CountBits(GetAllRoadBits(tile)) != 1) return false;
			if (IsRoadOwner(tile, ROADTYPE_ROAD, OWNER_TOWN)) return true;
			if (IsRoadOwner(tile, ROADTYPE_ROAD, _current_player)) return true;
			return false;
	}
}

/* static */ bool AITile::IsBuildableRectangle(TileIndex tile, uint width, uint height)
{
	uint tx, ty;

	tx = AIMap::GetTileX(tile);
	ty = AIMap::GetTileY(tile);

	for (uint x = tx; x < width + tx; x++) {
		for (uint y = ty; y < height + ty; y++) {
			if (!IsBuildable(AIMap::GetTileIndex(x, y))) return false;
		}
	}

	return true;
}

/* static */ bool AITile::IsWater(TileIndex tile)
{
	if (!::IsValidTile(tile)) return false;

	return ::GetTileType(tile) == MP_WATER;
}

/* static */ bool AITile::IsSteepSlope(Slope slope)
{
	if (slope == SLOPE_INVALID) return false;

	return ::IsSteepSlope((::Slope)slope);
}

/* static */ bool AITile::IsHalftileSlope(Slope slope)
{
	if (slope == SLOPE_INVALID) return false;

	return ::IsHalftileSlope((::Slope)slope);
}

/* static */ AITile::Slope AITile::GetSlope(TileIndex tile)
{
	if (!::IsValidTile(tile)) return SLOPE_INVALID;

	return (Slope)::GetTileSlope(tile, NULL);
}

/* static */ AITile::Slope AITile::GetComplementSlope(Slope slope)
{
	if (slope == SLOPE_INVALID) return SLOPE_INVALID;
	if (IsSteepSlope(slope)) return SLOPE_INVALID;
	if (IsHalftileSlope(slope)) return SLOPE_INVALID;

	return (Slope)::ComplementSlope((::Slope)slope);
}

/* static */ int32 AITile::GetHeight(TileIndex tile)
{
	if (!::IsValidTile(tile)) return false;

	return ::TileHeight(tile);
}

/* static */ AICompany::CompanyIndex AITile::GetOwner(TileIndex tile)
{
	if (!::IsValidTile(tile)) return AICompany::INVALID_COMPANY;
	if (::IsTileType(tile, MP_HOUSE)) return AICompany::INVALID_COMPANY;
	if (::IsTileType(tile, MP_INDUSTRY)) return AICompany::INVALID_COMPANY;

	return AICompany::ResolveCompanyIndex((AICompany::CompanyIndex)(byte)::GetTileOwner(tile));
}

/* static */ int32 AITile::GetCargoAcceptance(TileIndex tile, CargoID cargo_type, uint width, uint height, uint radius)
{
	if (!::IsValidTile(tile)) return false;

	AcceptedCargo accepts;
	::GetAcceptanceAroundTiles(accepts, tile, width, height, _settings_game.station.modified_catchment ? radius : (uint)CA_UNMODIFIED);
	return accepts[cargo_type];
}

/* static */ int32 AITile::GetCargoProduction(TileIndex tile, CargoID cargo_type, uint width, uint height, uint radius)
{
	if (!::IsValidTile(tile)) return false;

	AcceptedCargo produced;
	::GetProductionAroundTiles(produced, tile, width, height, _settings_game.station.modified_catchment ? radius : (uint)CA_UNMODIFIED);
	return produced[cargo_type];
}

/* static */ int32 AITile::GetDistanceManhattanToTile(TileIndex tile_from, TileIndex tile_to)
{
	return AIMap::DistanceManhattan(tile_from, tile_to);
}

/* static */ int32 AITile::GetDistanceSquareToTile(TileIndex tile_from, TileIndex tile_to)
{
	return AIMap::DistanceSquare(tile_from, tile_to);
}

/* static */ bool AITile::RaiseTile(TileIndex tile, int32 slope)
{
	EnforcePrecondition(false, ::IsValidTile(tile));

	return AIObject::DoCommand(tile, slope, 1, CMD_TERRAFORM_LAND, false);
}

/* static */ bool AITile::LowerTile(TileIndex tile, int32 slope)
{
	EnforcePrecondition(false, ::IsValidTile(tile));

	return AIObject::DoCommand(tile, slope, 0, CMD_TERRAFORM_LAND, false);
}

/* static */ bool AITile::DemolishTile(TileIndex tile)
{
	EnforcePrecondition(false, ::IsValidTile(tile));

	return AIObject::DoCommand(tile, 0, 0, CMD_LANDSCAPE_CLEAR);
}

/* static */ bool AITile::IsWithinTownInfluence(TileIndex tile, TownID town_id)
{
	return AITown::IsWithinTownInfluence(town_id, tile);
}