/* $Id$ */

/*
 * 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 water_map.h Map accessors for water tiles. */

#ifndef WATER_MAP_H
#define WATER_MAP_H

#include "core/math_func.hpp"
#include "depot_type.h"
#include "tile_map.h"

enum WaterTileType {
	WATER_TILE_CLEAR,
	WATER_TILE_COAST,
	WATER_TILE_LOCK,
	WATER_TILE_DEPOT,
};

enum WaterClass {
	WATER_CLASS_SEA,
	WATER_CLASS_CANAL,
	WATER_CLASS_RIVER,
	WATER_CLASS_INVALID, ///< Used for industry tiles on land (also for oilrig if newgrf says so)
};

enum DepotPart {
	DEPOT_NORTH = 0x80,
	DEPOT_SOUTH = 0x81,
	DEPOT_END   = 0x84,
};

enum LockPart {
	LOCK_MIDDLE = 0x10,
	LOCK_LOWER  = 0x14,
	LOCK_UPPER  = 0x18,
	LOCK_END    = 0x1C
};

static inline WaterTileType GetWaterTileType(TileIndex t)
{
	assert(IsTileType(t, MP_WATER));

	if (_m[t].m5 == 0) return WATER_TILE_CLEAR;
	if (_m[t].m5 == 1) return WATER_TILE_COAST;
	if (IsInsideMM(_m[t].m5, LOCK_MIDDLE, LOCK_END)) return WATER_TILE_LOCK;

	assert(IsInsideMM(_m[t].m5, DEPOT_NORTH, DEPOT_END));
	return WATER_TILE_DEPOT;
}

static inline WaterClass GetWaterClass(TileIndex t)
{
	assert(IsTileType(t, MP_WATER) || IsTileType(t, MP_STATION) || IsTileType(t, MP_INDUSTRY));
	return (WaterClass)(IsTileType(t, MP_INDUSTRY) ? GB(_m[t].m1, 5, 2) : GB(_m[t].m3, 0, 2));
}

static inline void SetWaterClass(TileIndex t, WaterClass wc)
{
	assert(IsTileType(t, MP_WATER) || IsTileType(t, MP_STATION) || IsTileType(t, MP_INDUSTRY));
	if (IsTileType(t, MP_INDUSTRY)) {
		SB(_m[t].m1, 5, 2, wc);
	} else {
		SB(_m[t].m3, 0, 2, wc);
	}
}

/** IsWater return true if any type of clear water like ocean, river, canal */
static inline bool IsWater(TileIndex t)
{
	return GetWaterTileType(t) == WATER_TILE_CLEAR;
}

static inline bool IsSea(TileIndex t)
{
	return IsWater(t) && GetWaterClass(t) == WATER_CLASS_SEA;
}

static inline bool IsCanal(TileIndex t)
{
	return IsWater(t) && GetWaterClass(t) == WATER_CLASS_CANAL;
}

static inline bool IsRiver(TileIndex t)
{
	return IsWater(t) && GetWaterClass(t) == WATER_CLASS_RIVER;
}

static inline bool IsWaterTile(TileIndex t)
{
	return IsTileType(t, MP_WATER) && IsWater(t);
}

static inline bool IsCoast(TileIndex t)
{
	return GetWaterTileType(t) == WATER_TILE_COAST;
}

static inline TileIndex GetOtherShipDepotTile(TileIndex t)
{
	return t + (HasBit(_m[t].m5, 0) ? -1 : 1) * (HasBit(_m[t].m5, 1) ? TileDiffXY(0, 1) : TileDiffXY(1, 0));
}

static inline bool IsShipDepot(TileIndex t)
{
	return IsInsideMM(_m[t].m5, DEPOT_NORTH, DEPOT_END);
}

static inline bool IsShipDepotTile(TileIndex t)
{
	return IsTileType(t, MP_WATER) && IsShipDepot(t);
}

static inline Axis GetShipDepotAxis(TileIndex t)
{
	return (Axis)GB(_m[t].m5, 1, 1);
}

static inline DiagDirection GetShipDepotDirection(TileIndex t)
{
	return XYNSToDiagDir(GetShipDepotAxis(t), GB(_m[t].m5, 0, 1));
}

static inline bool IsLock(TileIndex t)
{
	return IsInsideMM(_m[t].m5, LOCK_MIDDLE, LOCK_END);
}

static inline DiagDirection GetLockDirection(TileIndex t)
{
	return (DiagDirection)GB(_m[t].m5, 0, 2);
}

static inline byte GetSection(TileIndex t)
{
	assert(GetWaterTileType(t) == WATER_TILE_LOCK || GetWaterTileType(t) == WATER_TILE_DEPOT);
	return GB(_m[t].m5, 0, 4);
}

static inline byte GetWaterTileRandomBits(TileIndex t)
{
	return _m[t].m4;
}


static inline void MakeShore(TileIndex t)
{
	SetTileType(t, MP_WATER);
	SetTileOwner(t, OWNER_WATER);
	_m[t].m2 = 0;
	_m[t].m3 = 0;
	_m[t].m4 = 0;
	_m[t].m5 = 1;
	SB(_m[t].m6, 2, 4, 0);
	_me[t].m7 = 0;
}

/**
 * Helper function for making a watery tile.
 * @param t The tile to change into water
 * @param o The owner of the water
 * @param wc The class of water the tile has to be
 * @param random_bits Eventual random bits to be set for this tile
 */
static inline void MakeWater(TileIndex t, Owner o, WaterClass wc, uint8 random_bits)
{
	SetTileType(t, MP_WATER);
	SetTileOwner(t, o);
	_m[t].m2 = 0;
	_m[t].m3 = wc;
	_m[t].m4 = random_bits;
	_m[t].m5 = 0;
	SB(_m[t].m6, 2, 4, 0);
	_me[t].m7 = 0;
}

/**
 * Make a sea tile.
 * @param t The tile to change into sea
 */
static inline void MakeSea(TileIndex t)
{
	MakeWater(t, OWNER_WATER, WATER_CLASS_SEA, 0);
}

/**
 * Make a river tile
 * @param t The tile to change into river
 * @param random_bits Random bits to be set for this tile
 */
static inline void MakeRiver(TileIndex t, uint8 random_bits)
{
	MakeWater(t, OWNER_WATER, WATER_CLASS_RIVER, random_bits);
}

/**
 * Make a canal tile
 * @param t The tile to change into canal
 * @param o The owner of the canal
 * @param random_bits Random bits to be set for this tile
 */
static inline void MakeCanal(TileIndex t, Owner o, uint8 random_bits)
{
	assert(o != OWNER_WATER);
	MakeWater(t, o, WATER_CLASS_CANAL, random_bits);
}

static inline void MakeShipDepot(TileIndex t, Owner o, DepotID did, DepotPart base, Axis a, WaterClass original_water_class)
{
	SetTileType(t, MP_WATER);
	SetTileOwner(t, o);
	_m[t].m2 = did;
	_m[t].m3 = original_water_class;
	_m[t].m4 = 0;
	_m[t].m5 = base + a * 2;
	SB(_m[t].m6, 2, 4, 0);
	_me[t].m7 = 0;
}

static inline void MakeLockTile(TileIndex t, Owner o, byte section, WaterClass original_water_class)
{
	SetTileType(t, MP_WATER);
	SetTileOwner(t, o);
	_m[t].m2 = 0;
	_m[t].m3 = original_water_class;
	_m[t].m4 = 0;
	_m[t].m5 = section;
	SB(_m[t].m6, 2, 4, 0);
	_me[t].m7 = 0;
}

static inline void MakeLock(TileIndex t, Owner o, DiagDirection d, WaterClass wc_lower, WaterClass wc_upper)
{
	TileIndexDiff delta = TileOffsByDiagDir(d);

	MakeLockTile(t, o, LOCK_MIDDLE + d, WATER_CLASS_CANAL);
	MakeLockTile(t - delta, o, LOCK_LOWER + d, wc_lower);
	MakeLockTile(t + delta, o, LOCK_UPPER + d, wc_upper);
}

#endif /* WATER_MAP_H */