Add list-rings

Adds list-rings, a method to implement item sending between inventories via shift-click.
Nice insider feature: a ring consisting of a single inventory list serves as nice clean-up method.
Also adds them to minimal game, and the standard inventory.
Craft output slots are not supported.

5 files changed, 156 insertions, 14 deletions

diff --git a/doc/lua_api.txt b/doc/lua_api.txt
index 012c6eae1..a65c53c1a 100644
--- a/doc/lua_api.txt
+++ b/doc/lua_api.txt
@@ -1340,6 +1340,17 @@ examples.
 #### `list[<inventory location>;<list name>;<X>,<Y>;<W>,<H>;<starting item index>]`
 * Show an inventory list
 
+#### `listring[<inventory location>;<list name>]`
+* Allows to create a ring of inventory lists
+* Shift-clicking on items in one element of the ring
+* will send them to the next inventory list inside the ring
+* The first occurrence of an element inside the ring will
+* determine the inventory where items will be sent to
+
+#### `listring[]`
+* Shorthand for doing `listring[<inventory location>;<list name>]`
+* for the last two inventory lists added by list[...]
+
 #### `listcolors[<slot_bg_normal>;<slot_bg_hover>]`
 * Sets background color of slots as `ColorString`
 * Sets background color of slots on mouse hovering
diff --git a/games/minimal/mods/default/init.lua b/games/minimal/mods/default/init.lua
index cf0a1c679..c51af594f 100644
--- a/games/minimal/mods/default/init.lua
+++ b/games/minimal/mods/default/init.lua
@@ -1158,7 +1158,8 @@ minetest.register_node("default:chest", {
 		meta:set_string("formspec",
 				"size[8,9]"..
 				"list[current_name;main;0,0;8,4;]"..
-				"list[current_player;main;0,5;8,4;]")
+				"list[current_player;main;0,5;8,4;]" ..
+				"listring[]")
 		meta:set_string("infotext", "Chest")
 		local inv = meta:get_inventory()
 		inv:set_size("main", 8*4)
@@ -1197,7 +1198,8 @@ minetest.register_node("default:chest_locked", {
 		meta:set_string("formspec",
 				"size[8,9]"..
 				"list[current_name;main;0,0;8,4;]"..
-				"list[current_player;main;0,5;8,4;]")
+				"list[current_player;main;0,5;8,4;]" ..
+				"listring[]")
 		meta:set_string("infotext", "Locked Chest")
 		meta:set_string("owner", "")
 		local inv = meta:get_inventory()
@@ -1261,7 +1263,11 @@ default.furnace_inactive_formspec =
 	"list[current_name;fuel;2,3;1,1;]"..
 	"list[current_name;src;2,1;1,1;]"..
 	"list[current_name;dst;5,1;2,2;]"..
-	"list[current_player;main;0,5;8,4;]"
+	"list[current_player;main;0,5;8,4;]" ..
+	"listring[current_name;dst]" ..
+	"listring[current_player;main]" ..
+	"listring[current_name;src]" ..
+	"listring[current_player;main]"
 
 minetest.register_node("default:furnace", {
 	description = "Furnace",
@@ -1398,7 +1404,11 @@ minetest.register_abm({
 				"list[current_name;fuel;2,3;1,1;]"..
 				"list[current_name;src;2,1;1,1;]"..
 				"list[current_name;dst;5,1;2,2;]"..
-				"list[current_player;main;0,5;8,4;]")
+				"list[current_player;main;0,5;8,4;]" ..
+				"listring[current_name;dst]" ..
+				"listring[current_player;main]" ..
+				"listring[current_name;src]" ..
+				"listring[current_player;main]")
 			return
 		end
 
diff --git a/src/guiFormSpecMenu.cpp b/src/guiFormSpecMenu.cpp
index ec829525b..0414dc41f 100644
--- a/src/guiFormSpecMenu.cpp
+++ b/src/guiFormSpecMenu.cpp
@@ -352,6 +352,40 @@ void GUIFormSpecMenu::parseList(parserData* data,std::string element)
 	errorstream<< "Invalid list element(" << parts.size() << "): '" << element << "'"  << std::endl;
 }
 
+void GUIFormSpecMenu::parseListRing(parserData* data, std::string element)
+{
+	if (m_gamedef == 0) {
+		errorstream << "WARNING: invalid use of 'listring' with m_gamedef==0" << std::endl;
+		return;
+	}
+
+	std::vector<std::string> parts = split(element, ';');
+
+	if (parts.size() == 2) {
+		std::string location = parts[0];
+		std::string listname = parts[1];
+
+		InventoryLocation loc;
+
+		if (location == "context" || location == "current_name")
+			loc = m_current_inventory_location;
+		else
+			loc.deSerialize(location);
+
+		m_inventory_rings.push_back(ListRingSpec(loc, listname));
+		return;
+	} else if ((element == "") && (m_inventorylists.size() > 1)) {
+		size_t siz = m_inventorylists.size();
+		// insert the last two inv list elements into the list ring
+		const ListDrawSpec &spa = m_inventorylists[siz - 2];
+		const ListDrawSpec &spb = m_inventorylists[siz - 1];
+		m_inventory_rings.push_back(ListRingSpec(spa.inventoryloc, spa.listname));
+		m_inventory_rings.push_back(ListRingSpec(spb.inventoryloc, spb.listname));
+	}
+	errorstream<< "Invalid list ring element(" << parts.size() << ", "
+		<< m_inventorylists.size() << "): '" << element << "'"  << std::endl;
+}
+
 void GUIFormSpecMenu::parseCheckbox(parserData* data,std::string element)
 {
 	std::vector<std::string> parts = split(element,';');
@@ -1661,6 +1695,11 @@ void GUIFormSpecMenu::parseElement(parserData* data, std::string element)
 		return;
 	}
 
+	if (type == "listring") {
+		parseListRing(data, description);
+		return;
+	}
+
 	if (type == "checkbox") {
 		parseCheckbox(data,description);
 		return;
@@ -3145,6 +3184,10 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 		// from m_selected_item to s.
 		u32 move_amount = 0;
 
+		// Set this number to a positive value to generate a move action
+		// from s to the next inventory ring.
+		u32 shift_move_amount = 0;
+
 		// Set this number to a positive value to generate a drop action
 		// from m_selected_item.
 		u32 drop_amount = 0;
@@ -3166,18 +3209,29 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 			}
 			else if(m_selected_item == NULL) {
 				if(s_count != 0) {
-					// Non-empty stack has been clicked: select it
+					// Non-empty stack has been clicked: select or shift-move it
 					m_selected_item = new ItemSpec(s);
 
+					u32 count;
 					if(button == 1)  // right
-						m_selected_amount = (s_count + 1) / 2;
+						count = (s_count + 1) / 2;
 					else if(button == 2)  // middle
-						m_selected_amount = MYMIN(s_count, 10);
+						count = MYMIN(s_count, 10);
 					else  // left
-						m_selected_amount = s_count;
+						count = s_count;
 
-					m_selected_dragging = true;
-					m_rmouse_auto_place = false;
+					if (!event.MouseInput.Shift) {
+						// no shift: select item
+						m_selected_amount = count;
+						m_selected_dragging = true;
+						m_rmouse_auto_place = false;
+					} else {
+						// shift pressed: move item
+						if (button != 1)
+							shift_move_amount = count;
+						else // count of 1 at left click like after drag & drop
+							shift_move_amount = 1;
+					}
 				}
 			}
 			else { // m_selected_item != NULL
@@ -3259,8 +3313,7 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 		}
 
 		// Possibly send inventory action to server
-		if(move_amount > 0)
-		{
+		if (move_amount > 0) {
 			// Send IACTION_MOVE
 
 			assert(m_selected_item && m_selected_item->isValid());
@@ -3308,8 +3361,57 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 			a->to_list = s.listname;
 			a->to_i = s.i;
 			m_invmgr->inventoryAction(a);
-		}
-		else if(drop_amount > 0) {
+		} else if (shift_move_amount > 0) {
+			u32 mis = m_inventory_rings.size();
+			u32 i = 0;
+			for (; i < mis; i++) {
+				const ListRingSpec &sp = m_inventory_rings[i];
+				if (sp.inventoryloc == s.inventoryloc
+						&& sp.listname == s.listname)
+					break;
+			}
+			do {
+				if (i >= mis) // if not found
+					break;
+				u32 to_inv_ind = (i + 1) % mis;
+				const ListRingSpec &to_inv_sp = m_inventory_rings[to_inv_ind];
+				InventoryList *list_from = inv_s->getList(s.listname);
+				if (!list_from)
+					break;
+				Inventory *inv_to = m_invmgr->getInventory(to_inv_sp.inventoryloc);
+				if (!inv_to)
+					break;
+				InventoryList *list_to = inv_to->getList(to_inv_sp.listname);
+				if (!list_to)
+					break;
+				ItemStack stack_from = list_from->getItem(s.i);
+				assert(shift_move_amount <= stack_from.count);
+
+				// find a place (or more than one) to add the new item
+				u32 slot_to = 0;
+				u32 ilt_size = list_to->getSize();
+				ItemStack leftover;
+				for (; slot_to < ilt_size && shift_move_amount > 0; slot_to++) {
+					list_to->itemFits(slot_to, stack_from, &leftover);
+					if (leftover.count < stack_from.count) {
+						infostream << "Handing IACTION_MOVE to manager" << std::endl;
+						IMoveAction *a = new IMoveAction();
+						a->count = MYMIN(shift_move_amount,
+							(u32) (stack_from.count - leftover.count));
+						shift_move_amount -= a->count;
+						a->from_inv = s.inventoryloc;
+						a->from_list = s.listname;
+						a->from_i = s.i;
+						a->to_inv = to_inv_sp.inventoryloc;
+						a->to_list = to_inv_sp.listname;
+						a->to_i = slot_to;
+						m_invmgr->inventoryAction(a);
+						stack_from = leftover;
+					}
+				}
+			} while (0);
+
+		} else if (drop_amount > 0) {
 			m_selected_content_guess = ItemStack(); // Clear
 
 			// Send IACTION_DROP
diff --git a/src/guiFormSpecMenu.h b/src/guiFormSpecMenu.h
index f04968aec..2ba47f7ff 100644
--- a/src/guiFormSpecMenu.h
+++ b/src/guiFormSpecMenu.h
@@ -121,6 +121,22 @@ class GUIFormSpecMenu : public GUIModalMenu
 		s32 start_item_i;
 	};
 
+	struct ListRingSpec
+	{
+		ListRingSpec()
+		{
+		}
+		ListRingSpec(const InventoryLocation &a_inventoryloc,
+				const std::string &a_listname):
+			inventoryloc(a_inventoryloc),
+			listname(a_listname)
+		{
+		}
+
+		InventoryLocation inventoryloc;
+		std::string listname;
+	};
+
 	struct ImageDrawSpec
 	{
 		ImageDrawSpec()
@@ -306,6 +322,7 @@ protected:
 
 
 	std::vector<ListDrawSpec> m_inventorylists;
+	std::vector<ListRingSpec> m_inventory_rings;
 	std::vector<ImageDrawSpec> m_backgrounds;
 	std::vector<ImageDrawSpec> m_images;
 	std::vector<ImageDrawSpec> m_itemimages;
@@ -384,6 +401,7 @@ private:
 
 	void parseSize(parserData* data,std::string element);
 	void parseList(parserData* data,std::string element);
+	void parseListRing(parserData* data,std::string element);
 	void parseCheckbox(parserData* data,std::string element);
 	void parseImage(parserData* data,std::string element);
 	void parseItemImage(parserData* data,std::string element);
diff --git a/src/player.cpp b/src/player.cpp
index 4a5e5ad91..26496259c 100644
--- a/src/player.cpp
+++ b/src/player.cpp
@@ -71,6 +71,7 @@ Player::Player(IGameDef *gamedef, const char *name):
 		//"image[1,0.6;1,2;player.png]"
 		"list[current_player;main;0,3.5;8,4;]"
 		"list[current_player;craft;3,0;3,3;]"
+		"listring[]"
 		"list[current_player;craftpreview;7,1;1,1;]";
 
 	// Initialize movement settings at default values, so movement can work if the server fails to send them