Reimplement native market pricing and goods trading

docs/wiki.rst

@@ -29,6 +29,7 @@ For the recommended method of using SARIF files in Ghidra, see:
 The Game itself
 ------------------
 - :doc:`Load balancing of the core game engine <wiki/load-balancing-table>`
+- :doc:`Market pricing and goods trading <wiki/market-trading>`
 - Game Mechanics
 - AI Behavior
 - Graphics and Sound Systems

docs/wiki/market-trading.md

@@ -0,0 +1,29 @@
+# Market pricing and goods trading
+
+The AI buys and sells resources using the game's price table. The trade routines
+handle storage and gold accounting; the decision to trade is made by their callers.
+
+| Function | Crusader 1.41 address | Behavior |
+| --- | --- | --- |
+| `GameStateStructures::getBuyPrice` | `0x004588A0` | Returns `(buyPrice / 5) * amount`. |
+| `GameStateStructures::getSellPrice` | `0x00458910` | Returns `(salesPrice / 5) * amount`. |
+| `AICState::buyGoods` | `0x004CC000` | Attempts resource storage, then deducts gold and displays the trade on success. |
+| `AICState::sellGoods` | `0x004CBFA0` | Credits gold and final-result statistics, removes resources, then displays the trade. |
+
+## Prices
+
+Prices are stored for lots of five goods. The game divides that price by five
+using integer division, then multiplies by the amount traded. For example, a
+table price of 14 and a trade of five goods produce a price of 10. The player
+argument does not affect the price calculation.
+
+## Buying and selling
+
+A purchase first attempts to store the goods. If storage fails, it returns
+without deducting gold or displaying a trade. The routine itself does not check
+whether the player can afford the purchase. Successful purchases reduce both
+the player's gold and their net market-gold total.
+
+A sale increases those two totals and the final-results gold statistic, then
+removes the sold goods. Both successful purchases and sales display the trade
+amount to the player.

src/OpenSHC/AI/AICState/buyGoods.cpp

@@ -0,0 +1,29 @@
+#include "../AICState.func.hpp"
+
+#include "OpenSHC/Game/GameStateStructures.func.hpp"
+#include "OpenSHC/Map/Buildings/BuildingsState.func.hpp"
+
+#include "OpenSHC/Globals/DAT_BuildingsState.hpp"
+#include "OpenSHC/Globals/DAT_GameState.hpp"
+
+namespace OpenSHC {
+namespace AI {
+
+    // FUNCTION: STRONGHOLDCRUSADER 0x004CC000
+    BOOLEnum AICState::buyGoods(int playerID, ResourceType resourceType, int amount)
+    {
+        int const cost = MACRO_CALL_MEMBER(Game::GameStateStructures_Func::getBuyPrice, DAT_GameState::ptr)(
+            playerID, resourceType, amount);
+        if (MACRO_CALL_MEMBER(Map::Buildings::BuildingsState_Func::processResourceGain, DAT_BuildingsState::ptr)(
+                playerID, resourceType, amount)) {
+            DAT_GameState::instance.playerDataArray[playerID].currentResources[Game::Resources::RT_GOLD] -= cost;
+            DAT_GameState::instance.playerDataArray[playerID].marketGold -= cost;
+            MACRO_CALL_MEMBER(Game::GameStateStructures_Func::displayPlayerTradeVisualEffect, DAT_GameState::ptr)(
+                playerID, 0, amount, resourceType);
+            return TRUE;
+        }
+        return FALSE;
+    }
+
+}
+}

src/OpenSHC/AI/AICState/sellGoods.cpp

@@ -0,0 +1,28 @@
+#include "../AICState.func.hpp"
+
+#include "OpenSHC/Game/GameStateStructures.func.hpp"
+#include "OpenSHC/Map/Buildings/BuildingsState.func.hpp"
+
+#include "OpenSHC/Globals/DAT_BuildingsState.hpp"
+#include "OpenSHC/Globals/DAT_GameState.hpp"
+#include "OpenSHC/Globals/DAT_GameSynchronyState.hpp"
+
+namespace OpenSHC {
+namespace AI {
+
+    // FUNCTION: STRONGHOLDCRUSADER 0x004CBFA0
+    void AICState::sellGoods(int playerID, ResourceType resourceType, int amount)
+    {
+        int const reward = MACRO_CALL_MEMBER(Game::GameStateStructures_Func::getSellPrice, DAT_GameState::ptr)(
+            playerID, resourceType, amount);
+        DAT_GameSynchronyState::instance.finalResults.finalGold[playerID] += reward;
+        DAT_GameState::instance.playerDataArray[playerID].currentResources[Game::Resources::RT_GOLD] += reward;
+        DAT_GameState::instance.playerDataArray[playerID].marketGold += reward;
+        MACRO_CALL_MEMBER(Map::Buildings::BuildingsState_Func::processResourceLoss, DAT_BuildingsState::ptr)(
+            playerID, resourceType, amount, 0);
+        MACRO_CALL_MEMBER(Game::GameStateStructures_Func::displayPlayerTradeVisualEffect, DAT_GameState::ptr)(
+            playerID, 1, -amount, resourceType);
+    }
+
+}
+}

src/OpenSHC/Game/GameStateStructures/getBuyPrice.cpp

@@ -0,0 +1,13 @@
+#include "../GameStateStructures.func.hpp"
+
+namespace OpenSHC {
+namespace Game {
+
+    // FUNCTION: STRONGHOLDCRUSADER 0x004588A0
+    int GameStateStructures::getBuyPrice(undefined4 playerID, int resourceType, int amount)
+    {
+        return (this->mapAndTime.buyAndSalesPriceArray[resourceType].buyPrice / 5) * amount;
+    }
+
+}
+}

src/OpenSHC/Game/GameStateStructures/getSellPrice.cpp

@@ -0,0 +1,13 @@
+#include "../GameStateStructures.func.hpp"
+
+namespace OpenSHC {
+namespace Game {
+
+    // FUNCTION: STRONGHOLDCRUSADER 0x00458910
+    int GameStateStructures::getSellPrice(int playerID, int resourceType, int amount)
+    {
+        return (this->mapAndTime.buyAndSalesPriceArray[resourceType].salesPrice / 5) * amount;
+    }
+
+}
+}

status/addresses-SHC-3BB0A8C1.txt

@@ -17715,13 +17715,13 @@ SHC_3BB0A8C1_0x00458840 | 0.0% | Pending
 
 SHC_3BB0A8C1_0x00458890 | 0.0% | Pending
 
-SHC_3BB0A8C1_0x004588A0 | 0.0% | Pending
+SHC_3BB0A8C1_0x004588A0 | 100.0% | Reimplemented
 
 SHC_3BB0A8C1_0x004588D0 | 0.0% | Pending
 
 SHC_3BB0A8C1_0x004588F0 | 0.0% | Pending
 
-SHC_3BB0A8C1_0x00458910 | 0.0% | Pending
+SHC_3BB0A8C1_0x00458910 | 100.0% | Reimplemented
 
 SHC_3BB0A8C1_0x00458940 | 0.0% | Pending
 
@@ -34857,9 +34857,9 @@ SHC_3BB0A8C1_0x004CBA50 | 0.0% | Pending
 
 SHC_3BB0A8C1_0x004CBE30 | 0.0% | Pending
 
-SHC_3BB0A8C1_0x004CBFA0 | 0.0% | Pending
+SHC_3BB0A8C1_0x004CBFA0 | 100.0% | Reimplemented
 
-SHC_3BB0A8C1_0x004CC000 | 0.0% | Pending
+SHC_3BB0A8C1_0x004CC000 | 100.0% | Reimplemented
 
 SHC_3BB0A8C1_0x004CC070 | 0.0% | Pending