vcmi/client/battle/CBattleFieldController.cpp

/*
 * CBattleFieldController.cpp, part of VCMI engine
 *
 * Authors: listed in file AUTHORS in main folder
 *
 * License: GNU General Public License v2.0 or later
 * Full text of license available in license.txt file, in main folder
 *
 */
#include "StdInc.h"
#include "CBattleFieldController.h"
#include "CBattleInterface.h"
#include "CBattleInterfaceClasses.h"
#include "CBattleSiegeController.h"
#include "CBattleObstacleController.h"
#include "../CBitmapHandler.h"
#include "../CGameInfo.h"
#include "../../CCallback.h"
#include "../gui/SDL_Extensions.h"
#include "../gui/CGuiHandler.h"
#include "../CPlayerInterface.h"
#include "../gui/CCursorHandler.h"
#include "../../lib/BattleFieldHandler.h"
#include "../../lib/CConfigHandler.h"
#include "../../lib/CStack.h"
#include "../../lib/spells/ISpellMechanics.h"

CBattleFieldController::CBattleFieldController(CBattleInterface * owner):
	owner(owner),
	previouslyHoveredHex(-1),
	currentlyHoveredHex(-1),
	attackingHex(-1)
{
	OBJ_CONSTRUCTION_CAPTURING_ALL_NO_DISPOSE;
	pos.w = owner->pos.w;
	pos.h = owner->pos.h;

	//preparing cells and hexes
	cellBorder = BitmapHandler::loadBitmap("CCELLGRD.BMP");
	CSDL_Ext::alphaTransform(cellBorder);
	cellShade = BitmapHandler::loadBitmap("CCELLSHD.BMP");
	CSDL_Ext::alphaTransform(cellShade);


	if(!owner->siegeController)
	{
		auto bfieldType = owner->curInt->cb->battleGetBattlefieldType();

		if(bfieldType == BattleField::NONE)
		{
			logGlobal->error("Invalid battlefield returned for current battle");
		}
		else
		{
			background = BitmapHandler::loadBitmap(bfieldType.getInfo()->graphics, false);
		}
	}
	else
	{
		std::string backgroundName = owner->siegeController->getBattleBackgroundName();
		background = BitmapHandler::loadBitmap(backgroundName, false);
	}

	//preparing graphic with cell borders
	cellBorders = CSDL_Ext::newSurface(background->w, background->h, cellBorder);
	//copying palette
	for (int g=0; g<cellBorder->format->palette->ncolors; ++g) //we assume that cellBorders->format->palette->ncolors == 256
	{
		cellBorders->format->palette->colors[g] = cellBorder->format->palette->colors[g];
	}
	//palette copied
	for (int i=0; i<GameConstants::BFIELD_HEIGHT; ++i) //rows
	{
		for (int j=0; j<GameConstants::BFIELD_WIDTH-2; ++j) //columns
		{
			int x = 58 + (i%2==0 ? 22 : 0) + 44*j;
			int y = 86 + 42 *i;
			for (int cellX = 0; cellX < cellBorder->w; ++cellX)
			{
				for (int cellY = 0; cellY < cellBorder->h; ++cellY)
				{
					if (y+cellY < cellBorders->h && x+cellX < cellBorders->w)
						* ((Uint8*)cellBorders->pixels + (y+cellY) *cellBorders->pitch + (x+cellX)) |= *((Uint8*)cellBorder->pixels + cellY *cellBorder->pitch + cellX);
				}
			}
		}
	}

	backgroundWithHexes = CSDL_Ext::newSurface(background->w, background->h, screen);


	for (int h = 0; h < GameConstants::BFIELD_SIZE; ++h)
	{
		auto hex = std::make_shared<CClickableHex>();
		hex->myNumber = h;
		hex->pos = hexPosition(h);
		hex->myInterface = owner;
		bfield.push_back(hex);
	}

	//for(auto hex : bfield)
	//	addChild(hex.get());
}

CBattleFieldController::~CBattleFieldController()
{
	SDL_FreeSurface(background);
	SDL_FreeSurface(cellBorders);
	SDL_FreeSurface(backgroundWithHexes);
	SDL_FreeSurface(cellBorder);
	SDL_FreeSurface(cellShade);
}

void CBattleFieldController::showBackgroundImage(SDL_Surface *to)
{
	blitAt(background, owner->pos.x, owner->pos.y, to);
	if (settings["battle"]["cellBorders"].Bool())
	{
		CSDL_Ext::blit8bppAlphaTo24bpp(cellBorders, nullptr, to, &owner->pos);
	}
}

void CBattleFieldController::showBackgroundImageWithHexes(SDL_Surface *to)
{
	blitAt(backgroundWithHexes, owner->pos.x, owner->pos.y, to);
}

void CBattleFieldController::redrawBackgroundWithHexes(const CStack *activeStack)
{
	attackableHexes.clear();
	if (activeStack)
		occupyableHexes = owner->curInt->cb->battleGetAvailableHexes(activeStack, true, &attackableHexes);

	auto accessibility = owner->curInt->cb->getAccesibility();

	for(int i = 0; i < accessibility.size(); i++)
		stackCountOutsideHexes[i] = (accessibility[i] == EAccessibility::ACCESSIBLE);

	//prepare background graphic with hexes and shaded hexes
	blitAt(background, 0, 0, backgroundWithHexes);

	owner->obstacleController->redrawBackgroundWithHexes(backgroundWithHexes);

	if (settings["battle"]["stackRange"].Bool())
	{
		std::vector<BattleHex> hexesToShade = occupyableHexes;
		hexesToShade.insert(hexesToShade.end(), attackableHexes.begin(), attackableHexes.end());
		for (BattleHex hex : hexesToShade)
		{
			int i = hex.getY(); //row
			int j = hex.getX()-1; //column
			int x = 58 + (i%2==0 ? 22 : 0) + 44*j;
			int y = 86 + 42 *i;
			SDL_Rect temp_rect = genRect(cellShade->h, cellShade->w, x, y);
			CSDL_Ext::blit8bppAlphaTo24bpp(cellShade, nullptr, backgroundWithHexes, &temp_rect);
		}
	}

	if(settings["battle"]["cellBorders"].Bool())
		CSDL_Ext::blit8bppAlphaTo24bpp(cellBorders, nullptr, backgroundWithHexes, nullptr);
}

void CBattleFieldController::showHighlightedHex(SDL_Surface *to, BattleHex hex, bool darkBorder)
{
	int x = 14 + (hex.getY() % 2 == 0 ? 22 : 0) + 44 *(hex.getX()) + owner->pos.x;
	int y = 86 + 42 *hex.getY() + owner->pos.y;
	SDL_Rect temp_rect = genRect (cellShade->h, cellShade->w, x, y);
	CSDL_Ext::blit8bppAlphaTo24bpp (cellShade, nullptr, to, &temp_rect);
	if(!darkBorder && settings["battle"]["cellBorders"].Bool())
		CSDL_Ext::blit8bppAlphaTo24bpp(cellBorder, nullptr, to, &temp_rect); //redraw border to make it light green instead of shaded
}

void CBattleFieldController::showHighlightedHexes(SDL_Surface *to)
{
	bool delayedBlit = false; //workaround for blitting enemy stack hex without mouse shadow with stack range on
	if(owner->activeStack && settings["battle"]["stackRange"].Bool())
	{
		std::set<BattleHex> set = owner->curInt->cb->battleGetAttackedHexes(owner->activeStack, currentlyHoveredHex, attackingHex);
		for(BattleHex hex : set)
			if(hex != currentlyHoveredHex)
				showHighlightedHex(to, hex, false);

		// display the movement shadow of the stack at b (i.e. stack under mouse)
		const CStack * const shere = owner->curInt->cb->battleGetStackByPos(currentlyHoveredHex, false);
		if(shere && shere != owner->activeStack && shere->alive())
		{
			std::vector<BattleHex> v = owner->curInt->cb->battleGetAvailableHexes(shere, true, nullptr);
			for(BattleHex hex : v)
			{
				if(hex != currentlyHoveredHex)
					showHighlightedHex(to, hex, false);
				else if(!settings["battle"]["mouseShadow"].Bool())
					delayedBlit = true; //blit at the end of method to avoid graphic artifacts
				else
					showHighlightedHex(to, hex, true); //blit now and blit 2nd time later for darker shadow - avoids graphic artifacts
			}
		}
	}

	for(int b=0; b<GameConstants::BFIELD_SIZE; ++b)
	{
		if(bfield[b]->strictHovered && bfield[b]->hovered)
		{
			if(previouslyHoveredHex == -1)
				previouslyHoveredHex = b; //something to start with
			if(currentlyHoveredHex == -1)
				currentlyHoveredHex = b; //something to start with

			if(currentlyHoveredHex != b) //repair hover info
			{
				previouslyHoveredHex = currentlyHoveredHex;
				currentlyHoveredHex = b;
			}
			if(settings["battle"]["mouseShadow"].Bool() || delayedBlit)
			{
				const spells::Caster *caster = nullptr;
				const CSpell *spell = nullptr;

				spells::Mode mode = spells::Mode::HERO;

				if(owner->spellToCast)//hero casts spell
				{
					spell = SpellID(owner->spellToCast->actionSubtype).toSpell();
					caster = owner->getActiveHero();
				}
				else if(owner->creatureSpellToCast >= 0 && owner->stackCanCastSpell && owner->creatureCasting)//stack casts spell
				{
					spell = SpellID(owner->creatureSpellToCast).toSpell();
					caster = owner->activeStack;
					mode = spells::Mode::CREATURE_ACTIVE;
				}

				if(caster && spell) //when casting spell
				{
					// printing shaded hex(es)
					spells::BattleCast event(owner->curInt->cb.get(), caster, mode, spell);
					auto shaded = spell->battleMechanics(&event)->rangeInHexes(currentlyHoveredHex);

					for(BattleHex shadedHex : shaded)
					{
						if((shadedHex.getX() != 0) && (shadedHex.getX() != GameConstants::BFIELD_WIDTH - 1))
							showHighlightedHex(to, shadedHex, true);
					}
				}
				else if(owner->active || delayedBlit) //always highlight pointed hex, keep this condition last in this method for correct behavior
				{
					if(currentlyHoveredHex.getX() != 0
					 && currentlyHoveredHex.getX() != GameConstants::BFIELD_WIDTH - 1)
						showHighlightedHex(to, currentlyHoveredHex, true); //keep true for OH3 behavior: hovered hex frame "thinner"
				}
			}
		}
	}
}

Rect CBattleFieldController::hexPosition(BattleHex hex) const
{
	int x = 14 + ((hex.getY())%2==0 ? 22 : 0) + 44*hex.getX() + owner->pos.x;
	int y = 86 + 42 *hex.getY() + owner->pos.y;
	int w = cellShade->w;
	int h = cellShade->h;
	return Rect(x, y, w, h);
}

bool CBattleFieldController::isPixelInHex(Point const & position)
{
	assert(cellShade);
	return CSDL_Ext::SDL_GetPixel(cellShade, position.x, position.y) != 0;
}

BattleHex CBattleFieldController::getHoveredHex()
{
	for ( auto const & hex : bfield)
		if (hex->hovered && hex->strictHovered)
			return hex->myNumber;

	return BattleHex::INVALID;
}

void CBattleFieldController::setBattleCursor(BattleHex myNumber)
{
	Rect hoveredHexPos = hexPosition(myNumber);
	CCursorHandler *cursor = CCS->curh;

	const double subdividingAngle = 2.0*M_PI/6.0; // Divide a hex into six sectors.
	const double hexMidX = hoveredHexPos.x + hoveredHexPos.w/2.0;
	const double hexMidY = hoveredHexPos.y + hoveredHexPos.h/2.0;
	const double cursorHexAngle = M_PI - atan2(hexMidY - cursor->ypos, cursor->xpos - hexMidX) + subdividingAngle/2; //TODO: refactor this nightmare
	const double sector = fmod(cursorHexAngle/subdividingAngle, 6.0);
	const int zigzagCorrection = !((myNumber/GameConstants::BFIELD_WIDTH)%2); // Off-by-one correction needed to deal with the odd battlefield rows.

	std::vector<int> sectorCursor; // From left to bottom left.
	sectorCursor.push_back(8);
	sectorCursor.push_back(9);
	sectorCursor.push_back(10);
	sectorCursor.push_back(11);
	sectorCursor.push_back(12);
	sectorCursor.push_back(7);

	const bool doubleWide = owner->activeStack->doubleWide();
	bool aboveAttackable = true, belowAttackable = true;

	// Exclude directions which cannot be attacked from.
	// Check to the left.
	if (myNumber%GameConstants::BFIELD_WIDTH <= 1 || !vstd::contains(occupyableHexes, myNumber - 1))
	{
		sectorCursor[0] = -1;
	}
	// Check top left, top right as well as above for 2-hex creatures.
	if (myNumber/GameConstants::BFIELD_WIDTH == 0)
	{
			sectorCursor[1] = -1;
			sectorCursor[2] = -1;
			aboveAttackable = false;
	}
	else
	{
		if (doubleWide)
		{
			bool attackRow[4] = {true, true, true, true};

			if (myNumber%GameConstants::BFIELD_WIDTH <= 1 || !vstd::contains(occupyableHexes, myNumber - GameConstants::BFIELD_WIDTH - 2 + zigzagCorrection))
				attackRow[0] = false;
			if (!vstd::contains(occupyableHexes, myNumber - GameConstants::BFIELD_WIDTH - 1 + zigzagCorrection))
				attackRow[1] = false;
			if (!vstd::contains(occupyableHexes, myNumber - GameConstants::BFIELD_WIDTH + zigzagCorrection))
				attackRow[2] = false;
			if (myNumber%GameConstants::BFIELD_WIDTH >= GameConstants::BFIELD_WIDTH - 2 || !vstd::contains(occupyableHexes, myNumber - GameConstants::BFIELD_WIDTH + 1 + zigzagCorrection))
				attackRow[3] = false;

			if (!(attackRow[0] && attackRow[1]))
				sectorCursor[1] = -1;
			if (!(attackRow[1] && attackRow[2]))
				aboveAttackable = false;
			if (!(attackRow[2] && attackRow[3]))
				sectorCursor[2] = -1;
		}
		else
		{
			if (!vstd::contains(occupyableHexes, myNumber - GameConstants::BFIELD_WIDTH - 1 + zigzagCorrection))
				sectorCursor[1] = -1;
			if (!vstd::contains(occupyableHexes, myNumber - GameConstants::BFIELD_WIDTH + zigzagCorrection))
				sectorCursor[2] = -1;
		}
	}
	// Check to the right.
	if (myNumber%GameConstants::BFIELD_WIDTH >= GameConstants::BFIELD_WIDTH - 2 || !vstd::contains(occupyableHexes, myNumber + 1))
	{
		sectorCursor[3] = -1;
	}
	// Check bottom right, bottom left as well as below for 2-hex creatures.
	if (myNumber/GameConstants::BFIELD_WIDTH == GameConstants::BFIELD_HEIGHT - 1)
	{
		sectorCursor[4] = -1;
		sectorCursor[5] = -1;
		belowAttackable = false;
	}
	else
	{
		if (doubleWide)
		{
			bool attackRow[4] = {true, true, true, true};

			if (myNumber%GameConstants::BFIELD_WIDTH <= 1 || !vstd::contains(occupyableHexes, myNumber + GameConstants::BFIELD_WIDTH - 2 + zigzagCorrection))
				attackRow[0] = false;
			if (!vstd::contains(occupyableHexes, myNumber + GameConstants::BFIELD_WIDTH - 1 + zigzagCorrection))
				attackRow[1] = false;
			if (!vstd::contains(occupyableHexes, myNumber + GameConstants::BFIELD_WIDTH + zigzagCorrection))
				attackRow[2] = false;
			if (myNumber%GameConstants::BFIELD_WIDTH >= GameConstants::BFIELD_WIDTH - 2 || !vstd::contains(occupyableHexes, myNumber + GameConstants::BFIELD_WIDTH + 1 + zigzagCorrection))
				attackRow[3] = false;

			if (!(attackRow[0] && attackRow[1]))
				sectorCursor[5] = -1;
			if (!(attackRow[1] && attackRow[2]))
				belowAttackable = false;
			if (!(attackRow[2] && attackRow[3]))
				sectorCursor[4] = -1;
		}
		else
		{
			if (!vstd::contains(occupyableHexes, myNumber + GameConstants::BFIELD_WIDTH + zigzagCorrection))
				sectorCursor[4] = -1;
			if (!vstd::contains(occupyableHexes, myNumber + GameConstants::BFIELD_WIDTH - 1 + zigzagCorrection))
				sectorCursor[5] = -1;
		}
	}

	// Determine index from sector.
	int cursorIndex;
	if (doubleWide)
	{
		sectorCursor.insert(sectorCursor.begin() + 5, belowAttackable ? 13 : -1);
		sectorCursor.insert(sectorCursor.begin() + 2, aboveAttackable ? 14 : -1);

		if (sector < 1.5)
			cursorIndex = static_cast<int>(sector);
		else if (sector >= 1.5 && sector < 2.5)
			cursorIndex = 2;
		else if (sector >= 2.5 && sector < 4.5)
			cursorIndex = (int) sector + 1;
		else if (sector >= 4.5 && sector < 5.5)
			cursorIndex = 6;
		else
			cursorIndex = (int) sector + 2;
	}
	else
	{
		cursorIndex = static_cast<int>(sector);
	}

	// Generally should NEVER happen, but to avoid the possibility of having endless loop below... [#1016]
	if (!vstd::contains_if (sectorCursor, [](int sc) { return sc != -1; }))
	{
		logGlobal->error("Error: for hex %d cannot find a hex to attack from!", myNumber);
		attackingHex = -1;
		return;
	}

	// Find the closest direction attackable, starting with the right one.
	// FIXME: Is this really how the original H3 client does it?
	int i = 0;
	while (sectorCursor[(cursorIndex + i)%sectorCursor.size()] == -1) //Why hast thou forsaken me?
		i = i <= 0 ? 1 - i : -i; // 0, 1, -1, 2, -2, 3, -3 etc..
	int index = (cursorIndex + i)%sectorCursor.size(); //hopefully we get elements from sectorCursor
	cursor->changeGraphic(ECursor::COMBAT, sectorCursor[index]);
	switch (index)
	{
		case 0:
			attackingHex = myNumber - 1; //left
			break;
		case 1:
			attackingHex = myNumber - GameConstants::BFIELD_WIDTH - 1 + zigzagCorrection; //top left
			break;
		case 2:
			attackingHex = myNumber - GameConstants::BFIELD_WIDTH + zigzagCorrection; //top right
			break;
		case 3:
			attackingHex = myNumber + 1; //right
			break;
		case 4:
			attackingHex = myNumber + GameConstants::BFIELD_WIDTH + zigzagCorrection; //bottom right
			break;
		case 5:
			attackingHex = myNumber + GameConstants::BFIELD_WIDTH - 1 + zigzagCorrection; //bottom left
			break;
	}
	BattleHex hex(attackingHex);
	if (!hex.isValid())
		attackingHex = -1;
}

BattleHex CBattleFieldController::fromWhichHexAttack(BattleHex myNumber)
{
	//TODO far too much repeating code
	BattleHex destHex;
	switch(CCS->curh->frame)
	{
	case 12: //from bottom right
		{
			bool doubleWide = owner->activeStack->doubleWide();
			destHex = myNumber + ( (myNumber/GameConstants::BFIELD_WIDTH)%2 ? GameConstants::BFIELD_WIDTH : GameConstants::BFIELD_WIDTH+1 ) +
				(owner->activeStack->side == BattleSide::ATTACKER && doubleWide ? 1 : 0);
			if(vstd::contains(occupyableHexes, destHex))
				return destHex;
			else if(owner->activeStack->side == BattleSide::ATTACKER)
			{
				if (vstd::contains(occupyableHexes, destHex+1))
					return destHex+1;
			}
			else //if we are defender
			{
				if(vstd::contains(occupyableHexes, destHex-1))
					return destHex-1;
			}
			break;
		}
	case 7: //from bottom left
		{
			destHex = myNumber + ( (myNumber/GameConstants::BFIELD_WIDTH)%2 ? GameConstants::BFIELD_WIDTH-1 : GameConstants::BFIELD_WIDTH );
			if (vstd::contains(occupyableHexes, destHex))
				return destHex;
			else if(owner->activeStack->side == BattleSide::ATTACKER)
			{
				if(vstd::contains(occupyableHexes, destHex+1))
					return destHex+1;
			}
			else //we are defender
			{
				if(vstd::contains(occupyableHexes, destHex-1))
					return destHex-1;
			}
			break;
		}
	case 8: //from left
		{
			if(owner->activeStack->doubleWide() && owner->activeStack->side == BattleSide::DEFENDER)
			{
				std::vector<BattleHex> acc = owner->curInt->cb->battleGetAvailableHexes(owner->activeStack);
				if (vstd::contains(acc, myNumber))
					return myNumber - 1;
				else
					return myNumber - 2;
			}
			else
			{
				return myNumber - 1;
			}
			break;
		}
	case 9: //from top left
		{
			destHex = myNumber - ((myNumber/GameConstants::BFIELD_WIDTH) % 2 ? GameConstants::BFIELD_WIDTH + 1 : GameConstants::BFIELD_WIDTH);
			if(vstd::contains(occupyableHexes, destHex))
				return destHex;
			else if(owner->activeStack->side == BattleSide::ATTACKER)
			{
				if(vstd::contains(occupyableHexes, destHex+1))
					return destHex+1;
			}
			else //if we are defender
			{
				if(vstd::contains(occupyableHexes, destHex-1))
					return destHex-1;
			}
			break;
		}
	case 10: //from top right
		{
			bool doubleWide = owner->activeStack->doubleWide();
			destHex = myNumber - ( (myNumber/GameConstants::BFIELD_WIDTH)%2 ? GameConstants::BFIELD_WIDTH : GameConstants::BFIELD_WIDTH-1 ) +
				(owner->activeStack->side == BattleSide::ATTACKER && doubleWide ? 1 : 0);
			if(vstd::contains(occupyableHexes, destHex))
				return destHex;
			else if(owner->activeStack->side == BattleSide::ATTACKER)
			{
				if(vstd::contains(occupyableHexes, destHex+1))
					return destHex+1;
			}
			else //if we are defender
			{
				if(vstd::contains(occupyableHexes, destHex-1))
					return destHex-1;
			}
			break;
		}
	case 11: //from right
		{
			if(owner->activeStack->doubleWide() && owner->activeStack->side == BattleSide::ATTACKER)
			{
				std::vector<BattleHex> acc = owner->curInt->cb->battleGetAvailableHexes(owner->activeStack);
				if(vstd::contains(acc, myNumber))
					return myNumber + 1;
				else
					return myNumber + 2;
			}
			else
			{
				return myNumber + 1;
			}
			break;
		}
	case 13: //from bottom
		{
			destHex = myNumber + ( (myNumber/GameConstants::BFIELD_WIDTH)%2 ? GameConstants::BFIELD_WIDTH : GameConstants::BFIELD_WIDTH+1 );
			if(vstd::contains(occupyableHexes, destHex))
				return destHex;
			else if(owner->activeStack->side == BattleSide::ATTACKER)
			{
				if(vstd::contains(occupyableHexes, destHex+1))
					return destHex+1;
			}
			else //if we are defender
			{
				if(vstd::contains(occupyableHexes, destHex-1))
					return destHex-1;
			}
			break;
		}
	case 14: //from top
		{
			destHex = myNumber - ( (myNumber/GameConstants::BFIELD_WIDTH)%2 ? GameConstants::BFIELD_WIDTH : GameConstants::BFIELD_WIDTH-1 );
			if (vstd::contains(occupyableHexes, destHex))
				return destHex;
			else if(owner->activeStack->side == BattleSide::ATTACKER)
			{
				if(vstd::contains(occupyableHexes, destHex+1))
					return destHex+1;
			}
			else //if we are defender
			{
				if(vstd::contains(occupyableHexes, destHex-1))
					return destHex-1;
			}
			break;
		}
	}
	return -1;
}

bool CBattleFieldController::isTileAttackable(const BattleHex & number) const
{
	for (auto & elem : occupyableHexes)
	{
		if (BattleHex::mutualPosition(elem, number) != -1 || elem == number)
			return true;
	}
	return false;
}

bool CBattleFieldController::stackCountOutsideHex(const BattleHex & number) const
{
	return stackCountOutsideHexes[number];
}