Fixup pending research states when loading savegames

src/game.cpp

@@ -2262,6 +2262,8 @@ static bool writeCompListFile(const char *pFileName);
 static bool loadSaveStructTypeList(const char *pFileName);
 static bool writeStructTypeListFile(const char *pFileName);
 
+static void loadFixupResearchPendingStates();
+
 static bool loadSaveResearch(const char *pFileName);
 static bool writeResearchFile(char *pFileName);
 
@@ -3300,6 +3302,11 @@ bool loadGame(const char *pGameToLoad, bool keepObjects, bool freeMem, bool User
 		}
 	}
 
+	if (UserSaveGame)
+	{
+		loadFixupResearchPendingStates();
+	}
+
 	// Load labels
 	aFileName[fileExten] = '\0';
 	strcat(aFileName, "labels.json");
@@ -7434,6 +7441,61 @@ static bool writeStructTypeListFile(const char *pFileName)
 	return true;
 }
 
+void loadFixupResearchPendingStates()
+{
+	const unsigned int players = static_cast<unsigned int>(game.maxPlayers);
+	for (int statInc = 0; statInc < asResearch.size(); statInc++)
+	{
+		for (unsigned int plr = 0; plr < players; plr++)
+		{
+			PLAYER_RESEARCH *pPlayerRes = &asPlayerResList[plr][statInc];
+
+			// Handle "pending" states
+			// - i.e. starting/cancelling research was queued, but the game tick was not processed before the save occurred
+			// - (Ideally the game would prevent this from happening by ensuring the save is queued to happen after the next tick...)
+			if (pPlayerRes->ResearchStatus & CANCELLED_RESEARCH_PENDING)
+			{
+				STRUCTURE *psLab = findResearchingFacilityByResearchIndex(apsStructLists, plr, statInc);
+				if (psLab == nullptr)
+				{
+					// check the mission list
+					psLab = findResearchingFacilityByResearchIndex(mission.apsStructLists, plr, statInc);
+				}
+
+				if (psLab != nullptr)
+				{
+					// Process the pending cancellation with immediate effect
+					debug(LOG_INFO, "Processing CANCELLED_RESEARCH_PENDING for: %s", asResearch[statInc].id.toUtf8().c_str());
+					::cancelResearch(psLab, ModeImmediate);
+				}
+				else
+				{
+					// did not find in *either* list - log and convert the CANCELLED_RESEARCH_PENDING status appropriately
+					if (pPlayerRes->currentPoints == 0)
+					{
+						// Reset this topic as not having been researched
+						debug(LOG_INFO, "Resetting CANCELLED_RESEARCH_PENDING to 0 for: %s", asResearch[statInc].id.toUtf8().c_str());
+						ResetResearchStatus(pPlayerRes);
+					}
+					else
+					{
+						// Set the cancelled flag
+						debug(LOG_INFO, "Resetting CANCELLED_RESEARCH_PENDING to CANCELLED_RESEARCH for: %s", asResearch[statInc].id.toUtf8().c_str());
+						MakeResearchCancelled(pPlayerRes);
+					}
+				}
+			}
+			else if (pPlayerRes->ResearchStatus & STARTED_RESEARCH_PENDING)
+			{
+				// Possible Future TODO: Could try to "recover", and queue this research item in an available research facility (however, the save doesn't contain which facility the user queued it in)
+				// For now: Just clear the STARTED_RESEARCH_PENDING bit, so that the user can re-start the research after loading the save
+				debug(LOG_INFO, "Resetting STARTED_RESEARCH_PENDING to 0 for: %s", asResearch[statInc].id.toUtf8().c_str());
+				pPlayerRes->ResearchStatus &= ~STARTED_RESEARCH_PENDING;
+			}
+		}
+	}
+}
+
 // -----------------------------------------------------------------------------------------
 // load up saved research file
 bool loadSaveResearch(const char *pFileName)

src/multiplay.cpp

@@ -1576,21 +1576,26 @@ bool sendResearchStatus(const STRUCTURE *psBuilding, uint32_t index, uint8_t pla
 	return true;
 }
 
-STRUCTURE *findResearchingFacilityByResearchIndex(unsigned player, unsigned index)
+STRUCTURE *findResearchingFacilityByResearchIndex(const PerPlayerStructureLists& pList, unsigned player, unsigned index)
 {
 	// Go through the structs to find the one doing this topic
-	for (STRUCTURE *psBuilding : apsStructLists[player])
+	for (STRUCTURE *psBuilding : pList[player])
 	{
 		if (psBuilding->pStructureType->type == REF_RESEARCH
-		    && ((RESEARCH_FACILITY *)psBuilding->pFunctionality)->psSubject
-		    && ((RESEARCH_FACILITY *)psBuilding->pFunctionality)->psSubject->ref - STAT_RESEARCH == index)
+			&& ((RESEARCH_FACILITY *)psBuilding->pFunctionality)->psSubject
+			&& ((RESEARCH_FACILITY *)psBuilding->pFunctionality)->psSubject->ref - STAT_RESEARCH == index)
 		{
 			return psBuilding;
 		}
 	}
 	return nullptr;  // Not found.
 }
 
+STRUCTURE *findResearchingFacilityByResearchIndex(unsigned player, unsigned index)
+{
+	return findResearchingFacilityByResearchIndex(apsStructLists, player, index);
+}
+
 bool recvResearchStatus(NETQUEUE queue)
 {
 	STRUCTURE			*psBuilding;

src/multiplay.h

@@ -36,6 +36,7 @@
 #include "levels.h"
 #include "console.h"
 #include "multirecv.h"
+#include "objmem.h"
 #include <vector>
 #include <string>
 #include <chrono>
@@ -323,7 +324,8 @@ bool sendBeacon(int32_t locX, int32_t locY, int32_t forPlayer, int32_t sender, c
 void startMultiplayerGame();
 void resetReadyStatus(bool bSendOptions, bool ignoreReadyReset = false);
 
-STRUCTURE *findResearchingFacilityByResearchIndex(unsigned player, unsigned index);
+STRUCTURE *findResearchingFacilityByResearchIndex(const PerPlayerStructureLists& pList, unsigned player, unsigned index);
+STRUCTURE *findResearchingFacilityByResearchIndex(unsigned player, unsigned index); // checks apsStructLists
 
 void sendSyncRequest(int32_t req_id, int32_t x, int32_t y, const BASE_OBJECT *psObj, const BASE_OBJECT *psObj2);