Implement HOOK_STEAL (#442)

* Implement HOOK_STEAL

SFALL_COMPATIBILITY.md

@@ -98,7 +98,7 @@ See [`https://sfall-team.github.io/sfall/`](https://sfall-team.github.io/sfall/)
 | KeyPress | `HOOK_KEYPRESS` | ✅ | Third hook arg is currently `0`; CE doesn't use VK codes. |
 | MouseClick | `HOOK_MOUSECLICK` | ✅ | - |
 | UseSkill | `HOOK_USESKILL` | 🚫 | - |
-| Steal | `HOOK_STEAL` | 🚫 | Et tu |
+| Steal | `HOOK_STEAL` | ✅ | - |
 | WithinPerception | `HOOK_WITHINPERCEPTION` | ✅ | - |
 | InventoryMove | `HOOK_INVENTORYMOVE` | ✅ | - |
 | InvenWield | `HOOK_INVENWIELD` | ✅ | - |

sfall_testing/hooks/gl_steal.ssl

@@ -0,0 +1,83 @@
+#include "sfall.h"
+#include "dik.h"
+#include "lib.arrays.h"
+
+variable steal_mode := 0;
+
+procedure steal_mode_name(variable mode) begin
+    if (mode == 1) then return "force_success";
+    if (mode == 2) then return "caught_fail";
+    if (mode == 3) then return "silent_fail";
+    if (mode == 4) then return "xp_override";
+    return "vanilla";
+end
+
+procedure steal_handler begin
+    variable
+        args := get_sfall_args,
+        thief := args[0],
+        target := args[1],
+        item := args[2],
+        is_planting := args[3],
+        quantity := args[4],
+        thief_name := "<null>",
+        target_name := "<null>",
+        item_name := "<null>";
+
+    if (thief) then thief_name := obj_name(thief);
+    if (target) then target_name := obj_name(target);
+    if (item) then item_name := obj_name(item);
+
+    display_msg(string_format6("steal mode=%s thief=%s target=%s item=%s planting=%d qty=%d",
+        steal_mode_name(steal_mode),
+        thief_name,
+        target_name,
+        item_name,
+        is_planting,
+        quantity));
+    display_msg(string_format1("steal args=%s", debug_array_str(args)));
+
+    if (thief != dude_obj) then return;
+
+    if (steal_mode == 1) then begin
+        display_msg("steal forcing success");
+        display_msg(sprintf(mstr_skill(571 + is_planting * 2), item_name));
+        set_sfall_return(1);
+    end else if (steal_mode == 2) then begin
+        display_msg("steal forcing caught failure");
+        display_msg(sprintf(mstr_skill(570 + is_planting * 2), item_name));
+        set_sfall_return(0);
+    end else if (steal_mode == 3) then begin
+        display_msg("steal forcing silent failure");
+        set_sfall_return(2);
+    end else if (steal_mode == 4) then begin
+        display_msg("steal forcing success with xp override 77");
+        display_msg(sprintf(mstr_skill(571 + is_planting * 2), item_name));
+        set_sfall_return(1);
+        set_sfall_return(77);
+    end
+end
+
+procedure keypress_handler begin
+    variable
+        pressed := get_sfall_arg_at(0),
+        key := get_sfall_arg_at(1);
+
+    if (not pressed) then return;
+    if (key != DIK_X) then return;
+
+    steal_mode += 1;
+    if (steal_mode > 4) then steal_mode := 0;
+
+    display_msg(string_format1("steal mode -> %s", steal_mode_name(steal_mode)));
+end
+
+procedure start begin
+    if (not game_loaded) then return;
+
+    display_msg("steal manual test ready: press X to cycle vanilla / force_success / caught_fail / silent_fail / xp_override");
+    display_msg("open a steal screen and move an item in either direction; mode 4 should award 77 XP for a successful action");
+
+    register_hook_proc(HOOK_KEYPRESS, keypress_handler);
+    register_hook_proc(HOOK_STEAL, steal_handler);
+end

src/inventory.cc

@@ -330,7 +330,7 @@ static void inventoryDrawCenteredText(unsigned char* buffer, int pitch, int widt
 static void inventoryExamineItem(Object* critter, Object* item);
 static void inventorySetLeftPaneCritter(Object* critter, Object* target, int inventoryWindowType);
 static void inventoryWindowOpenContextMenu(int eventCode, int inventoryWindowType);
-static InventoryMoveResult _move_inventory(Object* item, int slotIndex, Object* targetObj, bool isPlanting);
+static InventoryMoveResult _move_inventory(Object* item, int slotIndex, Object* targetObj, bool isPlanting, int* stealXpOverridePtr);
 static std::pair<int, int> barterComputeTablesValue(Object* dude, Object* npc, bool offerButton = false);
 static std::pair<int, int> barterComputeTablesWeight(Object* dude, Object* npc);
 static int barterAttemptTransaction(Object* dude, Object* offerTable, Object* npc, Object* barterTable);
@@ -4622,11 +4622,12 @@ int inventoryOpenLooting(Object* looter, Object* target)
                             _gStealSize += itemGetSize(_stack[_curr_stack]);
 
                             InventoryItem* inventoryItem = &(_pud->items[_pud->length - (slotIndex + _stack_offset[_curr_stack] + 1)]);
-                            InventoryMoveResult rc = _move_inventory(inventoryItem->item, slotIndex, _target_stack[_target_curr_stack], true);
+                            int stealXpOverride = -1;
+                            InventoryMoveResult rc = _move_inventory(inventoryItem->item, slotIndex, _target_stack[_target_curr_stack], true, &stealXpOverride);
                             if (rc == INVENTORY_MOVE_RESULT_CAUGHT_STEALING) {
                                 isCaughtStealing = true;
                             } else if (rc == INVENTORY_MOVE_RESULT_SUCCESS) {
-                                stealingXp += stealingXpBonus;
+                                stealingXp += stealXpOverride >= 0 ? stealXpOverride : stealingXpBonus;
                                 stealingXpBonus += 10;
                             }
 
@@ -4646,11 +4647,12 @@ int inventoryOpenLooting(Object* looter, Object* target)
                             _gStealSize += itemGetSize(_stack[_curr_stack]);
 
                             InventoryItem* inventoryItem = &(_target_pud->items[_target_pud->length - (slotIndex + _target_stack_offset[_target_curr_stack] + 1)]);
-                            InventoryMoveResult rc = _move_inventory(inventoryItem->item, slotIndex, _target_stack[_target_curr_stack], false);
+                            int stealXpOverride = -1;
+                            InventoryMoveResult rc = _move_inventory(inventoryItem->item, slotIndex, _target_stack[_target_curr_stack], false, &stealXpOverride);
                             if (rc == INVENTORY_MOVE_RESULT_CAUGHT_STEALING) {
                                 isCaughtStealing = true;
                             } else if (rc == INVENTORY_MOVE_RESULT_SUCCESS) {
-                                stealingXp += stealingXpBonus;
+                                stealingXp += stealXpOverride >= 0 ? stealXpOverride : stealingXpBonus;
                                 stealingXpBonus += 10;
                             }
 
@@ -4764,8 +4766,11 @@ int inventoryOpenStealing(Object* thief, Object* target)
 
 // 0x474708
 // note: this is looting and stealing, not the inventory screen
-static InventoryMoveResult _move_inventory(Object* item, int slotIndex, Object* targetObj, bool isPlanting)
+static InventoryMoveResult _move_inventory(Object* item, int slotIndex, Object* targetObj, bool isPlanting, int* stealXpOverridePtr)
 {
+    assert(stealXpOverridePtr != nullptr);
+    *stealXpOverridePtr = -1;
+
     bool needRefresh = true;
 
     Rect rect;
@@ -4827,13 +4832,17 @@ static InventoryMoveResult _move_inventory(Object* item, int slotIndex, Object*
             }
 
             if (quantityToMove != -1) {
+                bool skipMove = false;
                 if (_gIsSteal && _inven_dude == gDude) {
-                    if (skillsPerformStealing(_inven_dude, targetObj, item, true) == 0) {
+                    SkillStealResult stealResult = skillsPerformStealing(_inven_dude, targetObj, item, quantityToMove, true, stealXpOverridePtr);
+                    if (stealResult == SkillStealResult::Caught) {
                         result = INVENTORY_MOVE_RESULT_CAUGHT_STEALING;
+                    } else if (stealResult == SkillStealResult::Fail) {
+                        skipMove = true;
                     }
                 }
 
-                if (result != INVENTORY_MOVE_RESULT_CAUGHT_STEALING) {
+                if (!skipMove && result != INVENTORY_MOVE_RESULT_CAUGHT_STEALING) {
                     if (itemMove(_inven_dude, targetObj, item, quantityToMove) != -1) {
                         result = INVENTORY_MOVE_RESULT_SUCCESS;
                     } else {
@@ -4854,13 +4863,17 @@ static InventoryMoveResult _move_inventory(Object* item, int slotIndex, Object*
             }
 
             if (quantityToMove != -1) {
+                bool skipMove = false;
                 if (_gIsSteal && _inven_dude == gDude) {
-                    if (skillsPerformStealing(_inven_dude, targetObj, item, false) == 0) {
+                    SkillStealResult stealResult = skillsPerformStealing(_inven_dude, targetObj, item, quantityToMove, false, stealXpOverridePtr);
+                    if (stealResult == SkillStealResult::Caught) {
                         result = INVENTORY_MOVE_RESULT_CAUGHT_STEALING;
+                    } else if (stealResult == SkillStealResult::Fail) {
+                        skipMove = true;
                     }
                 }
 
-                if (result != INVENTORY_MOVE_RESULT_CAUGHT_STEALING) {
+                if (!skipMove && result != INVENTORY_MOVE_RESULT_CAUGHT_STEALING) {
                     if (itemMove(targetObj, _inven_dude, item, quantityToMove) == 0) {
                         if ((item->flags & OBJECT_IN_RIGHT_HAND) != 0) {
                             targetObj->fid = buildFid(FID_TYPE(targetObj->fid), targetObj->fid & 0xFFF, FID_ANIM_TYPE(targetObj->fid), 0, targetObj->rotation + 1);

src/sfall_script_hooks.cc

@@ -324,6 +324,54 @@ int scriptHooks_AmmoCost(Object* weapon, int rounds, int ammoCost, AmmoCostHookT
     return overrideAmmoCost >= 0 ? overrideAmmoCost : ammoCost;
 }
 
+/*
+Runs when checking an attempt to steal or plant an item.
+
+Critter arg0 - The thief
+Obj     arg1 - The target
+Item    arg2 - The item being stolen/planted
+int     arg3 - 0 when stealing, 1 when planting
+int     arg4 - Quantity being stolen/planted
+
+int     ret0 - Override the handler:
+               2 - fail without being caught
+               1 - success
+               0 - fail and get caught
+              -1 - use engine handler
+int     ret1 - Override XP gained for this action. Values below 0 are ignored.
+*/
+int scriptHooks_Steal(Object* thief, Object* target, Object* item, bool isPlanting, int quantity, int* xpOverride)
+{
+    assert(thief != nullptr);
+    assert(target != nullptr);
+    assert(item != nullptr);
+    assert(quantity >= 0);
+    assert(xpOverride != nullptr);
+
+    *xpOverride = -1;
+
+    ScriptHookCall hook(HOOK_STEAL, 2, { thief, target, item, isPlanting ? 1 : 0, quantity });
+    hook.call();
+
+    if (hook.numReturnValues() <= 0) {
+        return -1;
+    }
+
+    if (hook.numReturnValues() > 1) {
+        int overrideXp = hook.getReturnValueAt(1).asInt();
+        if (overrideXp >= 0) {
+            *xpOverride = overrideXp;
+        }
+    }
+
+    int overrideResult = hook.getReturnValueAt(0).asInt();
+    if (overrideResult >= 0 && overrideResult <= 2) {
+        return overrideResult;
+    }
+
+    return -1;
+}
+
 /*
 Runs immediately after a critter dies for any reason.
 

src/sfall_script_hooks.h

@@ -267,6 +267,7 @@ enum AmmoCostHookType {
 bool scriptHooksRegister(Program* program, HookType hookType, int procedureIndex);
 bool scriptHooks_StdProcedure(int procedureNumber, Object* self, Object* source, Object* target, int fixedParam, bool after);
 int scriptHooks_AmmoCost(Object* weapon, int rounds, int ammoCost, AmmoCostHookType hookType);
+int scriptHooks_Steal(Object* thief, Object* target, Object* item, bool isPlanting, int quantity, int* xpOverride);
 
 bool scriptHooksInit();
 void scriptHooksReset();

src/skill.cc

@@ -4,6 +4,8 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include <assert.h>
+
 #include "actions.h"
 #include "color.h"
 #include "combat.h"
@@ -24,6 +26,7 @@
 #include "random.h"
 #include "scripts.h"
 #include "settings.h"
+#include "sfall_script_hooks.h"
 #include "stat.h"
 #include "trait.h"
 
@@ -1028,8 +1031,30 @@ int skillUse(Object* obj, Object* target, int skill, int skillBonus)
 }
 
 // 0x4ABBE4
-int skillsPerformStealing(Object* thief, Object* target, Object* item, bool isPlanting)
+SkillStealResult skillsPerformStealing(Object* thief, Object* target, Object* item, int quantity, bool isPlanting, int* xpOverride)
 {
+    assert(thief != nullptr);
+    assert(target != nullptr);
+    assert(item != nullptr);
+    assert(quantity >= 0);
+    assert(xpOverride != nullptr);
+
+    *xpOverride = -1;
+
+    int hookXpOverride = -1;
+    int hookResult = scriptHooks_Steal(thief, target, item, isPlanting, quantity, &hookXpOverride);
+    if (hookXpOverride >= 0) {
+        *xpOverride = hookXpOverride;
+    }
+
+    if (hookResult == static_cast<int>(SkillStealResult::Fail)) {
+        return SkillStealResult::Fail;
+    }
+
+    if (hookResult == static_cast<int>(SkillStealResult::Success) || hookResult == static_cast<int>(SkillStealResult::Caught)) {
+        return static_cast<SkillStealResult>(hookResult);
+    }
+
     int howMuch;
 
     int stealModifier = -_gStealCount + 1;
@@ -1086,26 +1111,22 @@ int skillsPerformStealing(Object* thief, Object* target, Object* item, bool isPl
         // 571: You steal the %s.
         // 573: You plant the %s.
         messageListItem.num = isPlanting ? 573 : 571;
-        if (!messageListGetItem(&gSkillsMessageList, &messageListItem)) {
-            return -1;
+        if (messageListGetItem(&gSkillsMessageList, &messageListItem)) {
+            snprintf(text, sizeof(text), messageListItem.text, objectGetName(item));
+            displayMonitorAddMessage(text);
         }
 
-        snprintf(text, sizeof(text), messageListItem.text, objectGetName(item));
-        displayMonitorAddMessage(text);
-
-        return 1;
+        return SkillStealResult::Success;
     } else {
         // 570: You're caught stealing the %s.
         // 572: You're caught planting the %s.
         messageListItem.num = isPlanting ? 572 : 570;
-        if (!messageListGetItem(&gSkillsMessageList, &messageListItem)) {
-            return -1;
+        if (messageListGetItem(&gSkillsMessageList, &messageListItem)) {
+            snprintf(text, sizeof(text), messageListItem.text, objectGetName(item));
+            displayMonitorAddMessage(text);
         }
 
-        snprintf(text, sizeof(text), messageListItem.text, objectGetName(item));
-        displayMonitorAddMessage(text);
-
-        return 0;
+        return SkillStealResult::Caught;
     }
 }
 

src/skill.h

@@ -12,6 +12,12 @@ extern int _gIsSteal;
 extern int _gStealCount;
 extern int _gStealSize;
 
+enum class SkillStealResult {
+    Caught = 0,
+    Success = 1,
+    Fail = 2,
+};
+
 int skillsInit();
 void skillsReset();
 void skillsExit();
@@ -35,7 +41,7 @@ char* skillGetDescription(int skill);
 char* skillGetAttributes(int skill);
 int skillGetFrmId(int skill);
 int skillUse(Object* obj, Object* target, int skill, int skillBonus);
-int skillsPerformStealing(Object* thief, Object* target, Object* item, bool isPlanting);
+SkillStealResult skillsPerformStealing(Object* thief, Object* target, Object* item, int quantity, bool isPlanting, int* xpOverride);
 int skillGetGameDifficultyModifier(int skill);
 int skillUpdateLastUse(int skill);
 int skillsUsageSave(File* stream);