added quest_api.lua; added variable handling in fs_edit_preconditions.lua

fs_edit_preconditions.lua

@@ -1,6 +1,5 @@
 -- TODO: check inscription of a sign?
 -- TODO: invlist as dropdown of inventory lists at detected position
--- TODO: variable as dropdown of allowed variables
 
 -- Which diffrent types of preconditions are available?
 -- -> The following fields are part of a precondition:
@@ -11,7 +10,8 @@
 -- 	p_value		used to store the subtype of p_type
 --
 -- a state/variable:
---	p_variable	TODO
+--	p_variable	name of a variable the player has read access to;
+--	                dropdown list with allowed options
 --	p_operator	selected from values_operator
 --	p_var_cmp_value can be set freely by the player
 --
@@ -101,11 +101,29 @@ local values_operator = {"", "==", "~=", ">=", ">", "<=", "<", "not", "is_set",
 -- some internal ones...
 local check_variable = {
 	"- please select -",
-	"(internal) hour of ingame day",
+	"(internal) hour of ingame day", -- 2
-	"(internal) player's health points",
+	"(internal) player's health points", -- 3
 }
 
 
+-- get the list of variables the player has read access to
+local get_sorted_player_var_list = function(pname)
+	local var_list = {}
+	-- copy the values from check_variable
+	for i, v in ipairs(check_variable) do
+		table.insert(var_list, v)
+	end
+	-- get the list of variables the player can read
+	local tmp = yl_speak_up.get_quest_variables_with_read_access(pname)
+	-- sort that list (the dropdown formspec element returns just an index)
+	table.sort(tmp)
+	for i, v in ipairs(tmp) do
+		table.insert(var_list, v)
+	end
+	return var_list
+end
+
+
 -- returns a human-readable text as description of the precondition
 -- (as shown in the edit options dialog and in the edit precondition formspec)
 yl_speak_up.show_precondition = function(p)
@@ -120,14 +138,19 @@ yl_speak_up.show_precondition = function(p)
 	elseif(p.p_type == "function") then
 		return "function: evaluate "..tostring(p_value)
 	elseif(p.p_type == "state") then
-		if(p.p_operator == "not") then
+		if(not(p.p_operator)) then
-			return "not( "..tostring(p.p_variable).." )"
+			return "Error: Operator not defined."
+		elseif(p.p_operator == "not") then
+			return "not( VALUE_OF[ "..tostring(p.p_variable).." ] )"
 		elseif(p.p_operator == "is_set") then
-			return tostring(p.p_variable).." ~= nil (is_set)"
+			return "VALUE_OF[ "..tostring(p.p_variable).." ] ~= nil (is_set)"
 		elseif(p.p_operator == "is_unset") then
-			return tostring(p.p_variable).." == nil (is_unset)"
+			return "VALUE_OF[ "..tostring(p.p_variable).." ] == nil (is_unset)"
 		end
-		return tostring(p.p_variable).." "..tostring(p.p_operator).." "..
+		if(p.p_var_cmp_value == "") then
+			return "VALUE_OF[ "..tostring(p.p_variable).." ] "..tostring(p.p_operator).." \"\""
+		end
+		return "VALUE_OF[ "..tostring(p.p_variable).." ] "..tostring(p.p_operator).." "..
 			tostring(p.p_var_cmp_value)
 	elseif(p.p_type == "block") then
 		if(not(p.p_pos) or type(p.p_pos) ~= "table"
@@ -216,18 +239,65 @@ yl_speak_up.eval_precondition = function(player, n_id, p)
 		-- extremly powerful (executes any lua code)
 		return yl_speak_up.eval_precondition_function(player, p)
 	elseif(p.p_type == "state") then
-		-- TODO: implement
+		local var_val = false
---[[
+		if(not(p.p_variable) or p.p_variable == "") then
-		if(p.p_operator == "not") then
+			-- broken precondition
-			return "not( "..tostring(p.p_variable).." )"
+			return false
-		elseif(p.p_operator == "is_set") then
+		-- "(internal) hour of ingame day", -- 2
-			return tostring(p.p_variable).." ~= nil (is_set)"
+		elseif(p.p_variable == check_variable[2]) then
-		elseif(p.p_operator == "is_unset") then
+			-- timeofday is between 0..1; translate to 24 hours
-			return tostring(p.p_variable).." == nil (is_unset)"
+			var_val = math.floor((minetest.get_timeofday() * 24)+0.5)
+		-- "(internal) player's health points", -- 3
+		elseif(p.p_variable == check_variable[3]) then
+			var_val = player:get_hp()
+		else
+			local pname = player:get_player_name()
+			local owner = yl_speak_up.npc_owner[ n_id ]
+			-- get the value of the variable
+			var_val = yl_speak_up.get_quest_variable_value(owner, pname, p.p_variable)
 		end
-		return tostring(p.p_variable).." "..tostring(p.p_operator).." "..
+
-			tostring(p.p_var_cmp_value)
+		if(p.p_operator == "not") then
---]]
+			return not(var_val)
+		elseif(p.p_operator == "is_set") then
+			return var_val ~= nil
+		elseif(p.p_operator == "is_unset") then
+			return var_val == nil
+		-- for security reasons: do this manually instead of just evaluating a term
+		elseif(p.p_operator == "==") then
+			-- best do these comparisons in string form to make sure both are of same type
+			return tostring(var_val) == tostring(p.p_var_cmp_value)
+		elseif(p.p_operator == "~=") then
+			return tostring(var_val) ~= tostring(p.p_var_cmp_value)
+		elseif(p.p_operator == ">=") then
+			-- compare numeric if possible
+			if(tonumber(var_val) and tonumber(p.p_var_cmp_value)) then
+				return tonumber(var_val) >= tonumber(p.p_var_cmp_value)
+			-- fallback: compare as strings
+		else
+				return tostring(var_val) >= tostring(p.p_var_cmp_value)
+			end
+		elseif(p.p_operator == ">") then
+			if(tonumber(var_val) and tonumber(p.p_var_cmp_value)) then
+				return tonumber(var_val) >  tonumber(p.p_var_cmp_value)
+			else
+				return tostring(var_val) >  tostring(p.p_var_cmp_value)
+			end
+		elseif(p.p_operator == "<=") then
+			if(tonumber(var_val) and tonumber(p.p_var_cmp_value)) then
+				return tonumber(var_val) <= tonumber(p.p_var_cmp_value)
+			else
+				return tostring(var_val) <= tostring(p.p_var_cmp_value)
+			end
+		elseif(p.p_operator == "<") then
+			if(tonumber(var_val) and tonumber(p.p_var_cmp_value)) then
+				return tonumber(var_val) <  tonumber(p.p_var_cmp_value)
+			else
+				return tostring(var_val) <  tostring(p.p_var_cmp_value)
+			end
+		end
+		-- unsupported operator
+		return false
 	elseif(p.p_type == "block") then
 		if(not(p.p_pos) or type(p.p_pos) ~= "table"
 		  or not(p.p_pos.x) or not(p.p_pos.y) or not(p.p_pos.z)) then
@@ -386,7 +456,7 @@ yl_speak_up.input_fs_edit_preconditions = function(player, formname, fields)
 
 	-- comparison value for a variable
 	elseif(fields.var_cmp_value
-	  and data and data.what and data.what >= 5 and data.what <= 6) then
+	  and data and data.what and data.what == 2) then
 		data.var_cmp_value = fields.var_cmp_value
 	end
 
@@ -420,9 +490,10 @@ yl_speak_up.input_fs_edit_preconditions = function(player, formname, fields)
 
 		-- "an internal state (i.e. of a quest)", -- 2
 		if(data.what == 2) then
-			pq.p_value = values_operator[ data.operator ]
+			pq.p_value = "expression"
+			pq.p_operator = values_operator[ data.operator ]
 			pq.p_var_cmp_value = (data.var_cmp_value or "")
-			-- TODO: p_variable
+			pq.p_variable = data.variable_name
 
 		-- "a block somewhere", -- 3
 		elseif(data.what == 3) then
@@ -509,9 +580,14 @@ yl_speak_up.input_fs_edit_preconditions = function(player, formname, fields)
 
 	-- select data regarding a variable
 	elseif(fields.select_variable) then
-		-- TODO: this needs to include player-specific variables
+		-- get the list of available variables (with the same elements
-		local nr = table.indexof(check_variable, fields.select_variable)
+		-- and the same sort order as when the dropdown was displayed)
+		local var_list = get_sorted_player_var_list(pname)
+		local nr = table.indexof(var_list, fields.select_variable)
+		if(nr) then
 			yl_speak_up.speak_to[pname].tmp_prereq.variable = nr
+			yl_speak_up.speak_to[pname].tmp_prereq.variable_name = var_list[ nr ]
+		end
 
 	-- select data regarding an operator
 	elseif(fields.select_operator) then
@@ -649,13 +725,15 @@ yl_speak_up.get_fs_edit_preconditions = function(player, table_click_result)
 		if(not(data.operator) or data.operator == 1 or data.operator >= 8) then
 			field_for_value = "label[11.2,5.1;- not used for this operator -]"
 		end
-		-- TODO: the list of available variables needs to be extended
+		-- the list of available variables needs to be extended with the ones
-		--       with the ones the player has read access to
+		-- the player has read access to, and the order has to be constant
+		-- (because dropdown just returns an index)
+		local var_list = get_sorted_player_var_list(pname)
 		formspec = formspec..
 			"label[0.2,3.3;The following expression shall be true:]"..
 			"label[0.2,4.3;Name of variable:]"..
 			"dropdown[0.2,4.8;6.5,0.6;select_variable;"..
-				table.concat(check_variable, ",")..";"..
+				table.concat(var_list, ",")..";"..
 				tostring(data.variable)..";]"..
 			"label[7.0,4.3;Operator:]"..
 			"dropdown[7.0,4.8;4.0,0.6;select_operator;"..

init.lua

@@ -33,6 +33,8 @@ dofile(modpath .. "inventory.lua")
 dofile(modpath .. "trade_simple.lua")
 -- easily accessible list of all trades the NPC offers
 dofile(modpath .. "trade_list.lua")
+-- handle variables for quests for player-owned NPC
+dofile(modpath .. "quest_api.lua")
 -- the main functionality of the mod
 dofile(modpath .. "functions.lua")
 -- a way of determining a node position

quest_api.lua

@@ -0,0 +1,22 @@
+
+-- just some handling of variables
+
+yl_speak_up.player_vars = {}
+
+-- get the value of a variable used by a player in an NPC
+yl_speak_up.get_quest_variable_value = function(owner_name, current_player_name, variable_name)
+	-- TODO: actually implement
+	return tostring(owner_name).." "..tostring(current_player_name).." "..tostring(variable_name)
+end
+
+-- which variables can player pname read and use in preconditions?
+yl_speak_up.get_quest_variables_with_read_access = function(pname)
+	-- TODO: actually implement
+	return {"var_1","var_2","var_3", "var_4"}
+end
+
+-- which variables can player pname write and use in effects/results?
+yl_speak_up.get_quest_variables_with_write_access = function(pname)
+	-- TODO: actually implement
+	return {"var_1","var_2","var_3"}
+end