item_pickup_change_flags: "auto" item name

item_pickup_change_flags (and the underlying DgnTriggerable) can take
the item name "auto", in which case it automatically picks the item
placed on top of the marker.

2 files changed, 25 insertions, 7 deletions

diff --git a/crawl-ref/source/dat/clua/lm_flags.lua b/crawl-ref/source/dat/clua/lm_flags.lua
index c6b93b7a2b..996cd9dd52 100644
--- a/crawl-ref/source/dat/clua/lm_flags.lua
+++ b/crawl-ref/source/dat/clua/lm_flags.lua
@@ -52,7 +52,9 @@
 --        an item on its grid gets picked up.  Accepts the parameter
 --        "item", which is the plain name of the item its watching
 --        (i.e., "Orb of Zot" and "golden rune of Zot" rather than
---         "the Orb of Zot" or "a golden rune of Zot").
+--        "the Orb of Zot" or "a golden rune of Zot").  You can also
+--        just use "auto", in which case whichever item is on top of
+--        the marker will autoamically be chosen.
 --
 -- ChangeFlags is a Triggerable subclass, and the above three functions
 -- are just convenience functions which add a single triggerer.  Other
diff --git a/crawl-ref/source/dat/clua/lm_trig.lua b/crawl-ref/source/dat/clua/lm_trig.lua
index 11d47607f8..d08d3fa1bd 100644
--- a/crawl-ref/source/dat/clua/lm_trig.lua
+++ b/crawl-ref/source/dat/clua/lm_trig.lua
@@ -537,14 +537,17 @@ end
 --
 -- * item_moved: Wait for an item to move from one cell to another.
 --      Needs the parameter "target", who's value is the name of the
---      item that is being tracked.  The triggerable/marker must be placed
---      on top of the cell containing the item.
+--      item that is being tracked, or which can be "auto", in which
+--      case it will pick the item placed by the vault.  The
+--      triggerable/marker must be placed on top of the cell containing
+--      the item.
 --
 -- * item_pickup: Wait for an item to be picked up.  Needs the parameter
---      "target", who's value is the name of the item that is being tracked.
---      The triggerable/marker must be placed on top of the cell containing
---      the item.  Automatically takes care of the item moving from one
---      square to another without being picked up.
+--      "target", who's value is the name of the item that is being tracked,
+--      or which can be "auto", in which case it will pick the item placed
+--      by the vault.  The triggerable/marker must be placed on top of the
+--      cell containing the item.  Automatically takes care of the item
+--      moving from one square to another without being picked up.
 --
 -- * player_move: Wait for the player to move to a cell.  The
 --      triggerable/marker must be placed on top of cell in question.
@@ -626,6 +629,19 @@ function DgnTriggerer:activate(triggerable, marker, x, y)
     error("DgnTriggerer:activate(): triggerable is not activated")
   end
 
+  if self.type == "item_moved" or self.type == "item_pickup" then
+    if self.target == "auto" then
+      local items = dgn.items_at(marker:pos())
+
+      if #items == 0 then
+        error("No vault item for " .. self.type)
+      elseif #items > 1 then
+        error("Too many vault items for " .. self.type)
+      end
+      self.target = item.name(items[1])
+    end
+  end
+
   local et = dgn.dgn_event_type(self.type)
 
   if (dgn.dgn_event_is_position(et)) then