Changed interrupted butchering behaviour as per Johanna's

suggestions/observations:

1) Get rid of option swap_when_safe and its behaviour.

2) If auto-swap butchery is interrupted by teleportation or chagning levels
   (banishment) then auto-swap back if there's no monsters nearby.

2b) Do the same if butchery is interrupted and then later a large position
    change happens.

3) If auto-swap butchery is interrupted by something like poison damage,
   if the butchery is resumed and finished then swap back.

4) If auto-swap butchery is interrupted by a monster, then if the
   new option prompt_for_swap is set the game will ask if you wish to
   swap back from your butchering tool.

4b) Do the same if butchery is interrupted and then later a large
    position change lands you near some hostile monsters.


git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@7717 c06c8d41-db1a-0410-9941-cceddc491573

11 files changed, 169 insertions, 54 deletions

diff --git a/crawl-ref/docs/options_guide.txt b/crawl-ref/docs/options_guide.txt
index 27d16930e6..384da9e96a 100644
--- a/crawl-ref/docs/options_guide.txt
+++ b/crawl-ref/docs/options_guide.txt
@@ -58,7 +58,7 @@ The contents of this text are:
 4-i     Command Enhancements.
                 auto_list, easy_open, easy_unequip, easy_confirm, 
                 allow_self_target, easy_butcher, always_confirm_butcher, 
-                swap_when_safe, easy_quit_item_prompts, easy_exit_menu, 
+                prompt_for_swap, easy_quit_item_prompts, easy_exit_menu, 
                 sort_menus
 4-j     Message and Display Improvements.
                 hp_warning, mp_warning, hp_colour, mp_colour,
@@ -976,10 +976,12 @@ always_confirm_butcher = false
         one corpse on the square. If there are multiple corpses on a 
         square, you will always be prompted, regardless of this option.
 
-swap_when_safe = true
+prompt_for_swap = true
         If both this and easy_butcher are true, then if an auto-switch
-        butchery is interrupted, the auto-switch will be reversed as
-        soon as you are safe again.
+        butchery is interrupted by a hostile monster, the game will
+        ask if you wish to switch back to your weapon.  It will also
+        prompt you if after butchery is interupted you teleport or
+        change levels and find yourself near hostile monsters.
 
 easy_quit_item_prompts = true
         Setting this option to true allows the quitting of item listing 
diff --git a/crawl-ref/settings/init.txt b/crawl-ref/settings/init.txt
index 92ac56ee24..7c27112595 100644
--- a/crawl-ref/settings/init.txt
+++ b/crawl-ref/settings/init.txt
@@ -207,7 +207,7 @@ include = travel_stoppers.txt
 # allow_self_target = (yes | no | prompt)
 # easy_butcher = false
 # always_confirm_butcher = true
-# swap_when_safe         = false
+# prompt_for_swap        = false
 # easy_quit_item_prompts = false
 # easy_exit_menu         = false
 # sort_menus = pickup: true : basename, qualname, curse, qty
diff --git a/crawl-ref/source/acr.cc b/crawl-ref/source/acr.cc
index 79ddec8867..599a4cda5f 100644
--- a/crawl-ref/source/acr.cc
+++ b/crawl-ref/source/acr.cc
@@ -1487,24 +1487,6 @@ static void _input()
     if (need_to_autoinscribe())
         autoinscribe();
 
-    // XXX: Is there some smart way to avoid autoswitching back if we're
-    //      just about to continue butchering?
-    if (!you.turn_is_over && player_feels_safe
-        && you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED]
-        && you_tran_can_wear(EQ_WEAPON))
-    {
-        // Decrease value by 1. (0 means attribute is false, 1 = a, 2 = b, ...)
-        int weap = you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] - 1;
-        if (weap == ENDOFPACK)
-            weap = -1;
-
-        weapon_switch(weap);
-        print_stats();
-
-        // To prevent spam in case the weapon can't be switched back to.
-        you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
-    }
-
     handle_delay();
 
     _center_cursor();
diff --git a/crawl-ref/source/beam.cc b/crawl-ref/source/beam.cc
index 7751bd40fd..bde83713a3 100644
--- a/crawl-ref/source/beam.cc
+++ b/crawl-ref/source/beam.cc
@@ -2358,9 +2358,6 @@ mon_resist_type mons_ench_f2(monsters *monster, bolt &pbolt)
 
                 if (!player_monster_visible(monster))
                 {
-                    // Don't swap weapons just because you can't see it anymore!
-                    you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
-
                     // Also turn off autopickup.
                     Options.autopickup_on = false;
                     mpr("Deactivating autopickup; reactivate with Ctrl-A.",
diff --git a/crawl-ref/source/delay.cc b/crawl-ref/source/delay.cc
index 7514ffa44d..04c4de8663 100644
--- a/crawl-ref/source/delay.cc
+++ b/crawl-ref/source/delay.cc
@@ -308,6 +308,10 @@ void start_delay( delay_type type, int turns, int parm1, int parm2 )
     delay.parm2    = parm2;
     delay.started  = false;
 
+    // Paranoia
+    if (type == DELAY_WEAPON_SWAP)
+        you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
+
     // Handle zero-turn delays (possible with butchering).
     if (turns == 0)
     {
@@ -393,19 +397,12 @@ void stop_delay( bool stop_stair_travel )
                              "back to %s.", butcher_verb.c_str(),
                              (multiple_corpses ? "s" : ""), weapon.c_str());
 
-            // Maybe we should do precisely that, but that would entirely
-            // defeat the purpose of the weapon swap.
-//            you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
-
-            if (Options.swap_when_safe)
-            {
-                // Use weapon slot + 1, so weapon slot 'a' (== 0) doesn't
-                // return false when checking if
-                // you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED].
-                you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED]
-                    = (butcher_swap_weapon == -1 ? ENDOFPACK
-                                                 : butcher_swap_weapon) + 1;
-            }
+            // Use weapon slot + 1, so weapon slot 'a' (== 0) doesn't
+            // return false when checking if
+            // you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED].
+            you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED]
+                = (butcher_swap_weapon == -1 ? ENDOFPACK
+                                             : butcher_swap_weapon) + 1;
         }
         else
         {
@@ -539,6 +536,82 @@ void stop_butcher_delay()
     }
 }
 
+void handle_interrupted_swap(bool swap_if_safe, bool force_unsafe)
+{
+    if (!you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED]
+        || !you_tran_can_wear(EQ_WEAPON))
+    {
+        return;
+    }
+
+    // Decrease value by 1. (0 means attribute is false, 1 = a, 2 = b, ...)
+    int weap = you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] - 1;
+    if (weap == ENDOFPACK)
+        weap = -1;
+
+    const bool       safe   = i_feel_safe() && !force_unsafe;
+    const bool       prompt = Options.prompt_for_swap && !safe;
+    const delay_type delay  = current_delay_action();
+
+    // If we're going to prompt then update the window so the player can
+    // see what the monsters are.
+    if (prompt)
+        viewwindow(true, false);
+
+    if (delay == DELAY_WEAPON_SWAP)
+    {
+        ASSERT(!"handle_interrupted_swap() called while already swapping "
+                "weapons");
+        you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
+        return;
+    }
+    else if (!you.turn_is_over
+             && (delay == DELAY_ASCENDING_STAIRS
+                 || delay == DELAY_DESCENDING_STAIRS))
+    {
+        // We just arrived on the level, let rest of function do its stuff.
+        ;
+    }
+    else if (you.turn_is_over && delay == DELAY_NOT_DELAYED)
+    {
+        // Turn is over, set up a delay to do swapping next turn.
+        if (prompt && yesno("Switch back from butchering tool?", false)
+            || safe && swap_if_safe)
+        {
+            start_delay(DELAY_WEAPON_SWAP, 1, weap);
+            you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
+        }
+        return;
+    }
+    else if (delay != DELAY_NOT_DELAYED)
+    {
+        // If ATTR_WEAPON_SWAP_INTERRUPTED is set while a corpse is being
+        // butchered/bottled/offered, then fake a weapon swap delay.
+        if (delay == DELAY_BUTCHER || delay == DELAY_BOTTLE_BLOOD
+           || delay == DELAY_OFFER_CORPSE)
+        {
+            start_delay(DELAY_WEAPON_SWAP, 1, weap);
+            you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
+        }
+        return;
+    }
+
+    if (safe)
+    {
+        if (!swap_if_safe)
+            return;
+    }
+    else if (!prompt || !yesno("Switch back from butchering tool?", false))
+    {
+        return;
+    }
+
+    weapon_switch(weap);
+    print_stats();
+
+    you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
+}
+
 bool you_are_delayed( void )
 {
     return (!you.delay_queue.empty());
@@ -1151,6 +1224,12 @@ static void _finish_delay(const delay_queue_item &delay)
             {
                 autopickup();
             }
+
+            // If we were interrupted while butchering (by poisonig, for
+            // example) then resumed butchering and finished, swap back from
+            // butchering tool if appropriate.
+            if (you.delay_queue.size() == 1)
+                handle_interrupted_swap(true);
         }
         else
         {
@@ -1187,6 +1266,11 @@ static void _finish_delay(const delay_queue_item &delay)
             offer_corpse(delay.parm1);
             StashTrack.update_stash(); // Don't stash-track this corpse anymore.
         }
+        // If we were interrupted while butchering (by poisonig, for
+        // example) then resumed butchering and finished, swap back from
+        // butchering tool if appropriate.
+        if (you.delay_queue.size() == 1)
+            handle_interrupted_swap(true);
         break;
     }
     case DELAY_DROP_ITEM:
@@ -1653,7 +1737,7 @@ static bool _should_stop_activity(const delay_queue_item &item,
             || Options.activity_interrupts[item.type][ai]);
 }
 
-inline static void _monster_warning(activity_interrupt_type ai,
+inline static bool _monster_warning(activity_interrupt_type ai,
                                     const activity_interrupt_data &at,
                                     int atype)
 {
@@ -1661,7 +1745,7 @@ inline static void _monster_warning(activity_interrupt_type ai,
     {
         const monsters* mon = static_cast<const monsters*>(at.data);
         if (!mon->visible())
-            return;
+            return (false);
         if (at.context == "already seen" || at.context == "uncharm")
         {
             // Only say "comes into view" if the monster wasn't in view
@@ -1726,10 +1810,14 @@ inline static void _monster_warning(activity_interrupt_type ai,
 
         if (Options.tutorial_left)
             tutorial_first_monster(*mon);
+
+        return (true);
     }
+
+    return (false);
 }
 
-static void _paranoid_option_disable( activity_interrupt_type ai,
+static bool _paranoid_option_disable( activity_interrupt_type ai,
                                       const activity_interrupt_data &at )
 {
     if (ai == AI_HIT_MONSTER || ai == AI_MONSTER_ATTACKS)
@@ -1758,16 +1846,15 @@ static void _paranoid_option_disable( activity_interrupt_type ai,
                                            restart.end()).c_str());
             }
 
-            // Don't switch back after we encountered an invisible creature.
-            you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
-
             if (Options.tutorial_left)
             {
                 learned_something_new(TUT_INVISIBLE_DANGER);
                 Options.tut_seen_invisible = you.num_turns;
             }
         }
+        return (true);
     }
+    return (false);
 }
 
 // Returns true if any activity was stopped.
@@ -1777,7 +1864,7 @@ bool interrupt_activity( activity_interrupt_type ai,
     if (_interrupts_blocked > 0)
         return (false);
 
-    _paranoid_option_disable(ai, at);
+    bool was_monst = _paranoid_option_disable(ai, at);
 
     if (crawl_state.is_repeating_cmd())
         return interrupt_cmd_repeat(ai, at);
@@ -1802,8 +1889,11 @@ bool interrupt_activity( activity_interrupt_type ai,
         if (is_sanctuary(you.pos()))
             return (false);
 
-        _monster_warning(ai, at, item.type);
+        was_monst = _monster_warning(ai, at, item.type) || was_monst;
         stop_delay();
+        if (was_monst)
+            handle_interrupted_swap(false, true);
+
         return (true);
     }
 
@@ -1822,8 +1912,13 @@ bool interrupt_activity( activity_interrupt_type ai,
             {
                 if (is_run_delay( you.delay_queue[j].type ))
                 {
-                    _monster_warning(ai, at, you.delay_queue[j].type);
+                    was_monst =
+                        _monster_warning(ai, at, you.delay_queue[j].type)
+                        || was_monst;
+
                     stop_delay();
+                    if (was_monst)
+                        handle_interrupted_swap(false, true);
                     return (true);
                 }
             }
@@ -1831,6 +1926,9 @@ bool interrupt_activity( activity_interrupt_type ai,
             // Non-run queued delays can be discarded without any processing.
             you.delay_queue.erase( you.delay_queue.begin() + i,
                                    you.delay_queue.end() );
+            if (was_monst)
+                handle_interrupted_swap(false, true);
+
             return (true);
         }
     }
diff --git a/crawl-ref/source/delay.h b/crawl-ref/source/delay.h
index dd47926e18..55cb7bd1d4 100644
--- a/crawl-ref/source/delay.h
+++ b/crawl-ref/source/delay.h
@@ -77,6 +77,9 @@ bool is_run_delay(int delay);
 bool is_being_butchered(const item_def &item, bool just_first = true);
 bool is_vampire_feeding( void );
 void stop_butcher_delay();
+void handle_interrupted_swap(bool swap_if_safe = false,
+                             bool force_unsafe = false);
+
 void clear_macro_process_key_delay();
 
 const char *activity_interrupt_name(activity_interrupt_type ai);
diff --git a/crawl-ref/source/externs.h b/crawl-ref/source/externs.h
index dd52521d4c..f73d24df6c 100644
--- a/crawl-ref/source/externs.h
+++ b/crawl-ref/source/externs.h
@@ -1857,8 +1857,8 @@ public:
     bool        easy_butcher;    // autoswap to butchering tool
     bool        always_confirm_butcher; // even if only one corpse
     bool        chunks_autopickup; // Autopickup chunks after butchering
-    bool        swap_when_safe;  // If autoswapped butchery was interrupted,
-                                 // swap weapon back when safe.
+    bool        prompt_for_swap; // Prompt to switch back from butchering
+                                 // tool if hostile monsters are around.
     bool        list_rotten;     // list slots for rotting corpses/chunks
     bool        default_target;  // start targeting on a real target
     bool        autopickup_no_burden;   // don't autopickup if it changes burden
diff --git a/crawl-ref/source/fight.cc b/crawl-ref/source/fight.cc
index 7e702fd1a6..a47588edb9 100644
--- a/crawl-ref/source/fight.cc
+++ b/crawl-ref/source/fight.cc
@@ -4199,8 +4199,9 @@ void melee_attack::mons_apply_attack_flavour(const mon_attack_def &attk)
 
 void melee_attack::mons_perform_attack_rounds()
 {
-    const int nrounds   = atk->has_hydra_multi_attack() ? atk->number : 4;
-    const coord_def pos = defender->pos();
+    const int nrounds      = atk->has_hydra_multi_attack() ? atk->number : 4;
+    const coord_def pos    = defender->pos();
+    const bool was_delayed = you_are_delayed();
 
     // Melee combat, tell attacker to wield its melee weapon.
     atk->wield_melee_weapon();
@@ -4379,6 +4380,13 @@ void melee_attack::mons_perform_attack_rounds()
 
     if (def_copy)
         delete def_copy;
+
+    // Inivislbe monster might have interrupted butchering.
+    if (was_delayed && defender->atype() == ACT_PLAYER && perceived_attack
+        && !attacker_visible)
+    {
+        handle_interrupted_swap(false, true);
+    }
 }
 
 bool melee_attack::mons_perform_attack()
diff --git a/crawl-ref/source/files.cc b/crawl-ref/source/files.cc
index cb3ea53ddf..4bdf77b5f1 100644
--- a/crawl-ref/source/files.cc
+++ b/crawl-ref/source/files.cc
@@ -7,6 +7,7 @@
  */
 
 #include "AppHdr.h"
+#include "delay.h"
 #include "files.h"
 #include "version.h"
 
@@ -1343,6 +1344,18 @@ bool load( dungeon_feature_type stair_taken, load_mode_type load_mode,
     if (load_mode != LOAD_VISITOR)
         dungeon_events.fire_event(DET_ENTERED_LEVEL);
 
+    if (load_mode == LOAD_ENTER_LEVEL)
+    {
+        // If butchering was interrupted by switching levels (banishment)
+        // then switch back from butchering tool if there's no hostiles
+        // nearby.
+        handle_interrupted_swap(true);
+
+        // Forget about interrupted butchering, since we probably aren't going
+        // to get back to the corpse in time to finish things.
+        you.attribute[ATTR_WEAPON_SWAP_INTERRUPTED] = 0;
+    }
+
     return just_created_level;
 }                               // end load()
 
diff --git a/crawl-ref/source/initfile.cc b/crawl-ref/source/initfile.cc
index d256558f1d..5763bdc482 100644
--- a/crawl-ref/source/initfile.cc
+++ b/crawl-ref/source/initfile.cc
@@ -682,7 +682,7 @@ void game_options::reset_options()
     easy_butcher           = true;
     always_confirm_butcher = false;
     chunks_autopickup      = true;
-    swap_when_safe         = true;
+    prompt_for_swap        = true;
     list_rotten            = true;
     easy_confirm           = CONFIRM_SAFE_EASY;
     easy_quit_item_prompts = true;
@@ -2054,7 +2054,7 @@ void game_options::read_option_line(const std::string &str, bool runscript)
     else BOOL_OPTION(easy_butcher);
     else BOOL_OPTION(always_confirm_butcher);
     else BOOL_OPTION(chunks_autopickup);
-    else BOOL_OPTION(swap_when_safe);
+    else BOOL_OPTION(prompt_for_swap);
     else BOOL_OPTION(list_rotten);
     else if (key == "lua_file" && runscript)
     {
diff --git a/crawl-ref/source/spells3.cc b/crawl-ref/source/spells3.cc
index 959ae1bc95..4d89207f0e 100644
--- a/crawl-ref/source/spells3.cc
+++ b/crawl-ref/source/spells3.cc
@@ -1259,6 +1259,7 @@ static bool _teleport_player( bool allow_control, bool new_abyss_area )
     }
 
     coord_def pos(1, 0);
+    bool      large_change = false;
 
     if (is_controlled)
     {
@@ -1328,6 +1329,9 @@ static bool _teleport_player( bool allow_control, bool new_abyss_area )
             if (pos != you.pos())
                 clear_trapping_net();
 
+            if (!see_grid(pos))
+                large_change = true;
+
             you.moveto(pos);
 
             if (grd(you.pos()) != DNGN_FLOOR
@@ -1336,6 +1340,7 @@ static bool _teleport_player( bool allow_control, bool new_abyss_area )
                 || env.cgrid(you.pos()) != EMPTY_CLOUD)
             {
                 is_controlled = false;
+                large_change  = false;
             }
             else
             {
@@ -1396,14 +1401,21 @@ static bool _teleport_player( bool allow_control, bool new_abyss_area )
         else if ( see_grid(newpos) )
             mpr("Your surroundings seem slightly different.");
         else
+        {
             mpr("Your surroundings suddenly seem different.");
+            large_change = true;
+        }
 
         you.position = newpos;
 
         // Necessary to update the view centre.
         you.moveto(you.pos());
+
     }
 
+    if (large_change)
+        handle_interrupted_swap(true);
+
     return !is_controlled;
 }