worked on griefing protection

random_buildings/griefing_tool.lua

@@ -0,0 +1,129 @@
+
+    
+
+-- TODO: town angeben
+
+minetest.register_tool( "random_buildings:griefing_tool",
+{
+    description = "building modification liszence",
+    groups = {}, 
+    inventory_image = "default_tool_steelaxe.png", --TODO
+    wield_image = "",
+    wield_scale = {x=1,y=1,z=1},
+    stack_max = 1, -- it has to store information - thus only one can be stacked
+    liquids_pointable = true, -- it may be necessary to remove water sources
+    -- TODO
+    tool_capabilities = {
+        full_punch_interval = 1.0,
+        max_drop_level=0,
+        groupcaps={
+            -- For example:
+            fleshy={times={[2]=0.80, [3]=0.40}, maxwear=0.05, maxlevel=1},
+            snappy={times={[2]=0.80, [3]=0.40}, maxwear=0.05, maxlevel=1},
+            choppy={times={[3]=0.90}, maxwear=0.05, maxlevel=0}
+        }
+    },
+    node_placement_prediction = nil,
+    metadata = minetest.serialize( {x=0,y=0,z=0,village='?',usages=5,owner='?'} ), -- information about the village for which this tool is valid
+
+
+    -- give information about the liscense
+    on_place = function(itemstack, placer, pointed_thing)
+
+       local name = placer:get_player_name();
+       local item = itemstack:to_table();
+       local data = minetest.deserialize( item[ "metadata" ] or {});
+
+       -- do not replace if there is nothing to be done
+       if( not( data ) or not( data[ village ] )) then
+
+          minetest.chat_send_player( name, "This building modification liscense is invalid! Please destroy it.");
+
+       elseif( data.village ) then
+
+          --minetest.chat_send_player( name, "Node already is '"..( item[ "metadata"] or "?" ).."'. Nothing to do.");
+          minetest.chat_send_player( name, "This special building modification liscense, issued by the the village called "..tostring( data.village )..
+              ", located at "..minetest.pos_to_string( {x=data.x, y=data.y, z=data.z} )..", grants "..tostring( data.owner )..
+              " the right to remove up to "..tostring( data.usages ).." blocks in said village."); 
+
+       elseif( data.general ) then
+
+          minetest.chat_send_player( name, "This general building modification liscense grants "..tostring( data.owner )..
+              " the right to remove up to "..tostring( data.usages ).." blocks of houses from lumberjacks or clay traders."); 
+
+       else
+          minetest.chat_send_player( name, "Error: This building modification liscense is neither special nor general. Please destroy it.");
+       end
+    end,
+
+
+
+    -- remove the protection on a node and dig it immediately
+    on_use = function(itemstack, user, pointed_thing)
+
+       if( user == nil or pointed_thing == nil) then
+          return nil;
+       end
+       local name = user:get_player_name();
+ 
+       if( pointed_thing.type ~= "node" ) then
+          minetest.chat_send_player( name, "  Error: No node.");
+          return nil;
+       end
+
+       local pos  = minetest.get_pointed_thing_position( pointed_thing, above );
+       local node = minetest.env:get_node_or_nil( pos );
+       
+       if( node == nil ) then
+ 
+          minetest.chat_send_player( name, "Error: Target node not yet loaded. Please wait a moment for the server to catch up.");
+          return nil;
+       end
+ 
+       local item = itemstack:to_table();
+       local data = minetest.deserialize( item[ "metadata" ] or {});
+
+       local meta = minetest.env:get_meta( pos );
+       
+       if( not(meta) or not( data ) or (not( data[ village ] ) and not(data[general])) or not( data[ owner ])) then
+          minetest.chat_send_player( name, "This building modification liscense is invalid! Please destroy it.");
+          return nil;
+       end
+
+       local protection = random_buildings.is_protected( pos, node, digger, data );
+
+       if( protection == 0) then
+
+          minetest.chat_send_player( name, "Your building modification liscence is not needed here.");
+          return nil;
+     
+       -- the node is protected - and this liscence allows to modifiy it
+       elseif( protection == -1 ) then
+
+          -- remember that this liscense has been used one more times
+          data.usages = data.usages - 1;
+
+          item[ 'metadata' ] = minetest.serialize( data );
+
+          minetest.chat_send_player( name, 'Your building modification liscence allows you to modify this node. You can now dig it.');
+
+          if( data.usages < 1 ) then
+             -- TODO: destroy the liscence if it got used up
+          end      
+
+       -- an error occoured or the liszcence is not valid here (random_buildings.is_protected already printed an error message)
+       else
+          return nil;
+
+       end
+    end,
+})
+
+-- mese wrapped in paper - the mese is the payment for the blocks the player will later take
+minetest.register_craft({
+        output = 'random_buildings:griefing_tool',
+        recipe = {
+                { 'default:paper' },
+                { 'default:mese' },
+        }
+})

random_buildings/random_buildings_protect.lua

@@ -1,9 +1,25 @@
 
 
+-- sends a message to the digger if the node is part of a house owned by an npc
+--          2 in case of error
+--          1 if the player is not allowed to change the node
+-- returns  0 if the node is not protected
+--         -1 if the player is allowed to change the node anyway (due to a liszence)
+random_buildings.is_protected = function( pos, node, digger, data )
 
+   if( pos  == nil ) then
+      minetest.chat_send_player(digger:get_player_name(), 'Error: No position given for house protection check.');
+      return 2; -- error: state could not be determined
+   end
 
-random_buildings.orig_node_dig = minetest.node_dig;
+   if( node == nil ) then
-function minetest.node_dig(pos, node, digger)
+      node = minetest.env:get_node( pos );
+   end
+
+   if( node == nil or node.name == 'ignore' ) then
+      minetest.chat_send_player(digger:get_player_name(), 'Please wait a moment. Area not yet loaded.');
+      return 2; -- error: state could not be determined
+   end
 
    local meta = {};
 
@@ -14,38 +30,76 @@ function minetest.node_dig(pos, node, digger)
       meta = minetest.env:get_meta( pos );
    end
 
-   if( meta ) then
+   -- definitely not owned by an npc
+   if( not( meta )) then
+      return 0;
+   end
 
-      local owner_info = meta:get_string( 'owner_info');
+   -- has meta info bit is not owned by an npc
-      if( owner_info ~= nil and owner_info ~= '' ) then
+   local owner_info = meta:get_string( 'owner_info');
+   if( not( owner_info ) or owner_info == '' ) then
+      return 0;
+   end
 
-         local chest_pos = minetest.deserialize( owner_info );
+   -- the information about the owner is stored in the building chest - and there is no guarantee that that area is loaded
+   local chest_pos = minetest.deserialize( owner_info );
 
-         local chest_node = minetest.env:get_node( chest_pos );
+   local chest_node = minetest.env:get_node( chest_pos );
 
-         if( chest_node == nil or chest_node.name == 'ignore' ) then
+   if( chest_node == nil or chest_node.name == 'ignore' ) then
-            minetest.chat_send_player(digger:get_player_name(), 'This building is owned by someone. '..
+
+      minetest.chat_send_player(digger:get_player_name(), 'This building is owned by someone. '..
                  'Please wait a moment and dig this node again to find out by whom it is owned.');
-            return false;
+      return 1; -- this is protected - even though we don't know yet by whom
-         end
+   end
 
-         local chest_meta  = minetest.env:get_meta( chest_pos );
+   local chest_meta  = minetest.env:get_meta( chest_pos );
-         local owner_name  = chest_meta:get_string( 'owner' );
+   local owner_name  = chest_meta:get_string( 'owner' );
-         local village     = chest_meta:get_string( 'village' );
+   local village     = chest_meta:get_string( 'village' );
-         local village_pos = minetest.deserialize( chest_meta:get_string( 'village_pos' ));
+   local village_pos = minetest.deserialize( chest_meta:get_string( 'village_pos' ));
 
- 
+
--- TODO: check if a liscense is in the inv of the player
+   -- lone traders like lumberjacks or clay traders who live on their own outside villages
-         minetest.chat_send_player(digger:get_player_name(), 'This building is owned by '..( owner_name or ' (someone) ')..
+   if( not( village ) or not( village_pos )) then
+
+      -- check if a general liscense is in the inv of the player (for this, check data )
+      if( data and data.usages > 0 and data.owner == digger:get_player_name()) then
+
+         meta:set_string( 'owner_info', nil ); -- delete the protection
+         return -1; -- this way, the liscence knows that it has been used
+      end
+
+      minetest.chat_send_player(digger:get_player_name(), 'This building is owned by '..( owner_name or ' (someone) ')..
+                 '. You need a general building modification liscence in order to remove this node.'); 
+      return 1;
+
+   else
+
+      -- check if a fitting liscense is used (for this, check data )
+      if( data and data.usages > 0 and data.owner == digger:get_player_name()
+          and data.x == village_pos.x and data.y == village_pos.y and data.z == village_pos.z ) then
+
+         meta:set_string( 'owner_info', nil ); -- delete the protection
+         return -1; -- this way, the liscence knows that it has been used
+      end
+      minetest.chat_send_player(digger:get_player_name(), 'This building is owned by '..( owner_name or ' (someone) ')..
                  ', who lives in the village '..( village or '(unknown)' )..
                  '. You need a special building modification liscence - obtainable at the village center at '..
                  minetest.pos_to_string( {x=village_pos.x,y=village_pos.y,z=village_pos.z} )..
 --                 ..minetest.pos_to_string( minetest.deserialize( village_pos or {}))
                  ' - in order to remove this node.'); --..' chest_pos: '..tostring( minetest.serialize( chest_pos )));
-         return false;
+      return 1;
-      end
+   end
+end
+
+
+-- protect npc houses against griefing
+random_buildings.orig_node_dig = minetest.node_dig;
+function minetest.node_dig(pos, node, digger)
+
+   if( random_buildings.is_protected( pos, node, digger )==0) then
+
+      return random_buildings.orig_node_dig(pos, node, digger, nil);
    end
-
-   return random_buildings.orig_node_dig(pos, node, digger);
 end