/*
 * 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 <https://www.gnu.org/licenses/old-licenses/gpl-2.0>.
 */

/** @file tile_type.h Types related to tiles. */

#ifndef TILE_TYPE_H
#define TILE_TYPE_H

#include "core/strong_typedef_type.hpp"

static constexpr uint TILE_SIZE           = 16;                    ///< Tile size in world coordinates.
static constexpr uint TILE_UNIT_MASK      = TILE_SIZE - 1;         ///< For masking in/out the inner-tile world coordinate units.
static constexpr uint TILE_PIXELS         = 32;                    ///< Pixel distance between tile columns/rows in #ZOOM_BASE.
static constexpr uint TILE_HEIGHT         =  8;                    ///< Height of a height level in world coordinate AND in pixels in #ZOOM_BASE.

static constexpr uint MAX_BUILDING_PIXELS = 200;                   ///< Maximum height of a building in pixels in #ZOOM_BASE. (Also applies to "bridge buildings" on the bridge floor.)
static constexpr int MAX_VEHICLE_PIXEL_X  = 192;                   ///< Maximum width of a vehicle in pixels in #ZOOM_BASE.
static constexpr int MAX_VEHICLE_PIXEL_Y  = 96;                    ///< Maximum height of a vehicle in pixels in #ZOOM_BASE.

static constexpr uint MAX_TILE_HEIGHT     = 255;                   ///< Maximum allowed tile height

static constexpr uint MIN_HEIGHTMAP_HEIGHT = 1;                    ///< Lowest possible peak value for heightmap creation
static constexpr uint MIN_CUSTOM_TERRAIN_TYPE = 1;                 ///< Lowest possible peak value for world generation

static constexpr uint MIN_MAP_HEIGHT_LIMIT = 15;                   ///< Lower bound of maximum allowed heightlevel (in the construction settings)
static constexpr uint MAX_MAP_HEIGHT_LIMIT = MAX_TILE_HEIGHT;      ///< Upper bound of maximum allowed heightlevel (in the construction settings)

static constexpr uint MIN_SNOWLINE_HEIGHT = 2;                     ///< Minimum snowline height
static constexpr uint DEF_SNOWLINE_HEIGHT = 10;                    ///< Default snowline height
static constexpr uint MAX_SNOWLINE_HEIGHT = (MAX_TILE_HEIGHT - 2); ///< Maximum allowed snowline height

static constexpr uint DEF_SNOW_COVERAGE = 40;                      ///< Default snow coverage.
static constexpr uint DEF_DESERT_COVERAGE = 50;                    ///< Default desert coverage.

static constexpr size_t TILE_TYPE_BITS = 4; ///< How many bits in map array are dedicated for type of each tile.

/**
 * The different types of tiles.
 *
 * Each tile belongs to one type, according whatever is build on it.
 *
 * @note A railway with a crossing street is marked as TileType::Road.
 */
enum class TileType : uint8_t {
	Clear, ///< A tile without any structures, i.e. grass, rocks, farm fields etc.
	Railway, ///< A tile with railway.
	Road, ///< A tile with road and/or tram tracks.
	House, ///< A house by a town.
	Trees, ///< Tile with one or more trees.
	Station, ///< A tile of a station or airport.
	Water, ///< Water tile.
	Void, ///< Invisible tiles at the SW and SE border.
	Industry, ///< Part of an industry.
	TunnelBridge, ///< Tunnel entry/exit and bridge heads.
	Object, ///< Contains objects such as transmitters and owned land.
	End, ///< End marker.
	MaxSize = 1U << TILE_TYPE_BITS, ///< The maximum possible number of tile types to be stored in map.
};

static_assert(TileType::End <= TileType::MaxSize);

/**
 * Additional infos of a tile on a tropic game.
 *
 * The tropiczone is not modified during gameplay. It mainly affects tree growth. (desert tiles are visible though)
 *
 * In randomly generated maps:
 *  TropicZone::Desert: Generated everywhere, if there is neither water nor mountains (TileHeight >= 4) in a certain distance from the tile.
 *  TropicZone::Rainforest: Generated everywhere, if there is no desert in a certain distance from the tile.
 *  TropicZone::Normal: Everywhere else, i.e. between desert and rainforest and on sea (if you clear the water).
 *
 * In scenarios:
 *  TropicZone::Normal: Default value.
 *  TropicZone::Desert: Placed manually.
 *  TropicZone::Rainforest: Placed if you plant certain rainforest-trees.
 */
enum class TropicZone : uint8_t {
	Normal = 0, ///< Normal tropiczone
	Desert = 1, ///< Tile is desert
	Rainforest = 2, ///< Rainforest tile
};

/**
 * The index/ID of a Tile.
 *
 * It is compatible with int32 / int64 for easy math throughout the code.
 */
using TileIndex = StrongType::Typedef<uint32_t, struct TileIndexTag, StrongType::Compare, StrongType::Integer, StrongType::Compatible<int32_t>, StrongType::Compatible<int64_t>>;

/* Make sure the size is as expected. */
static_assert(sizeof(TileIndex) == 4);

/**
 * The very nice invalid tile marker
 */
inline constexpr TileIndex INVALID_TILE = TileIndex{ (uint32_t)-1 };

#endif /* TILE_TYPE_H */
