From 57328bdc83983346b3f46e84dfe25bc68d949136 Mon Sep 17 00:00:00 2001
From: Arseniy Shestakov <me@arseniyshestakov.com>
Date: Fri, 29 Jan 2016 22:43:35 +0300
Subject: [PATCH] Battles: implement basic drawbridge mechanics

Movement to blocking hex 94 not yet properly handled as stack movement code need to be rewritten first.
Also gate destruction not immidiately affect drawbridge state.
---
 lib/CBattleCallback.cpp | 24 ++++++++++++++++++++++--
 lib/CBattleCallback.h   |  1 +
 server/CGameHandler.cpp | 35 +++++++++++++++++++++++++++++++++++
 server/CGameHandler.h   |  1 +
 4 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/lib/CBattleCallback.cpp b/lib/CBattleCallback.cpp
index bdfb2580e..c5556d4c0 100644
--- a/lib/CBattleCallback.cpp
+++ b/lib/CBattleCallback.cpp
@@ -442,6 +442,15 @@ si8 CBattleInfoEssentials::battleGetWallState(int partOfWall) const
 	return getBattle()->si.wallState[partOfWall];
 }
 
+EDrawbridgeState CBattleInfoEssentials::battleGetDrawbridgeState() const
+{
+	RETURN_IF_NOT_BATTLE(EDrawbridgeState::NONE);
+	if(getBattle()->town == nullptr || getBattle()->town->fortLevel() == CGTownInstance::NONE)
+		return EDrawbridgeState::NONE;
+
+	return getBattle()->si.drawbridgeState;
+}
+
 si8 CBattleInfoCallback::battleHasWallPenalty( const CStack * stack, BattleHex destHex ) const
 {
 	return battleHasWallPenalty(stack, stack->position, destHex);
@@ -1129,9 +1138,20 @@ AccessibilityInfo CBattleInfoCallback::getAccesibility() const
 	}
 
 	//gate -> should be before stacks
-	if(battleGetSiegeLevel() > 0 && battleGetWallState(EWallPart::GATE) != EWallState::DESTROYED)
+	if(battleGetSiegeLevel() > 0)
 	{
-		ret[95] = ret[96] = EAccessibility::GATE; //block gate's hexes
+		EAccessibility::EAccessibility accessability = EAccessibility::ACCESSIBLE;
+		switch(battleGetDrawbridgeState())
+		{
+		case EDrawbridgeState::RAISED:
+			accessability = EAccessibility::GATE;
+			break;
+
+		case EDrawbridgeState::RAISED_BLOCKED:
+			accessability = EAccessibility::UNAVAILABLE;
+			break;
+		}
+		ret[95] = ret[96] = accessability;
 	}
 
 	//tiles occupied by standing stacks
diff --git a/lib/CBattleCallback.h b/lib/CBattleCallback.h
index 0c7323706..8d2fe69c0 100644
--- a/lib/CBattleCallback.h
+++ b/lib/CBattleCallback.h
@@ -199,6 +199,7 @@ public:
 	// for determining state of a part of the wall; format: parameter [0] - keep, [1] - bottom tower, [2] - bottom wall,
 	// [3] - below gate, [4] - over gate, [5] - upper wall, [6] - uppert tower, [7] - gate; returned value: 1 - intact, 2 - damaged, 3 - destroyed; 0 - no battle
 	si8 battleGetWallState(int partOfWall) const;
+	EDrawbridgeState battleGetDrawbridgeState() const;
 
 	//helpers
 	///returns all stacks, alive or dead or undead or mechanical :)
diff --git a/server/CGameHandler.cpp b/server/CGameHandler.cpp
index 368201a81..6f657ab80 100644
--- a/server/CGameHandler.cpp
+++ b/server/CGameHandler.cpp
@@ -1148,6 +1148,7 @@ int CGameHandler::moveStack(int stack, BattleHex dest)
 				handleDamageFromObstacle(*theLastObstacle, curStack);
 			}
 	}
+	updateDrawbridgeState();
 	return ret;
 }
 
@@ -3449,6 +3450,40 @@ bool CGameHandler::queryReply(QueryID qid, ui32 answer, PlayerColor player)
 
 static EndAction end_action;
 
+void CGameHandler::updateDrawbridgeState()
+{
+	BattleDrawbridgeStateChanged db;
+	db.state = gs->curB->si.drawbridgeState;
+	if(gs->curB->si.wallState[EWallPart::GATE] == EWallState::DESTROYED)
+	{
+		db.state = EDrawbridgeState::LOWERED_BORKED;
+	}
+	else if(db.state == EDrawbridgeState::LOWERED)
+	{
+		if(gs->curB->battleGetStackByPos(BattleHex(94), false) ||
+			gs->curB->battleGetStackByPos(BattleHex(95), false) ||
+			gs->curB->battleGetStackByPos(BattleHex(96), false))
+		{
+			db.state = EDrawbridgeState::LOWERED;
+		}
+		else
+			db.state = EDrawbridgeState::RAISED;
+	}
+	else if(db.state == EDrawbridgeState::RAISED || db.state == EDrawbridgeState::RAISED_BLOCKED)
+	{
+		if(gs->curB->battleGetStackByPos(BattleHex(94), false))
+			db.state = EDrawbridgeState::RAISED_BLOCKED;
+		else if(gs->curB->battleGetStackByPos(BattleHex(95), false) ||
+			gs->curB->battleGetStackByPos(BattleHex(96), false))
+		{
+			db.state = EDrawbridgeState::LOWERED;
+		}
+		else
+			db.state = EDrawbridgeState::RAISED;
+	}
+	sendAndApply(&db);
+}
+
 bool CGameHandler::makeBattleAction( BattleAction &ba )
 {
 	bool ok = true;
diff --git a/server/CGameHandler.h b/server/CGameHandler.h
index 104979140..7eacccf77 100644
--- a/server/CGameHandler.h
+++ b/server/CGameHandler.h
@@ -200,6 +200,7 @@ public:
 	PlayerColor getPlayerAt(CConnection *c) const;
 
 	void playerMessage( PlayerColor player, const std::string &message, ObjectInstanceID currObj);
+	void updateDrawbridgeState();
 	bool makeBattleAction(BattleAction &ba);
 	bool makeAutomaticAction(const CStack *stack, BattleAction &ba); //used when action is taken by stack without volition of player (eg. unguided catapult attack)
 	bool makeCustomAction(BattleAction &ba);