Support [set/clear_variable] inside [modify_unit/side]

data/lua/wml-tags.lua

@@ -105,11 +105,12 @@ function wml_actions.store_gold(cfg)
 	if team then wml.variables[cfg.variable or "gold"] = team.gold end
 end
 
-function wml_actions.clear_variable(cfg)
+function wml_actions.clear_variable(cfg, variables)
 	local names = cfg.name or
 		helper.wml_error "[clear_variable] missing required name= attribute."
+	if variables == nil then variables = wml.variables end
 	for w in utils.split(names) do
-		wml.variables[utils.trim(w)] = nil
+		variables[utils.trim(w)] = nil
 	end
 end
 

data/lua/wml/modify_side.lua

@@ -91,16 +91,24 @@ function wesnoth.wml_actions.modify_side(cfg)
 			end
 		end
 
+		local ai, replace_ai = {}, false
+		for k, v in ipairs(cfg) do
+			local tag, content = v[1], v[2]
+			if tag == "ai" then
+				table.insert(ai, T.ai(content))
+				if content.ai_algorithm then
+					replace_ai = true
+				end
+			elseif tag == "set_variable" then
+				wesnoth.wml_actions.set_variable(v[2], side.variables)
+			elseif tag == "clear_variable" then
+				wesnoth.wml_actions.clear_variable(cfg, side.variables)
+			end
+		end
+		
 		if cfg.switch_ai then
 			wesnoth.switch_ai(side.side, cfg.switch_ai)
 		end
-		local ai, replace_ai = {}, false
-		for next_ai in wml.child_range(cfg, "ai") do
-			table.insert(ai, T.ai(next_ai))
-			if next_ai.ai_algorithm then
-				replace_ai = true
-			end
-		end
 		if #ai > 0 then
 			if replace_ai then
 				wesnoth.switch_ai(side.side, ai)

data/lua/wml/modify_unit.lua

@@ -55,6 +55,9 @@ local known_tags = make_set {
 	"trait",
 	"filter",
 	"status",
+	"set_variable",
+	-- todo: "set_variables",
+	"clear_variable",
 }
 
 local function is_simple(cfg)
@@ -137,11 +140,14 @@ local function simple_modify_unit(cfg)
 					tagcontent = wml.parsed(tagcontent)
 				end
 				u:add_modification(tagname, tagcontent);
-			end
+			elseif tagname == "status" then
-			if tagname == "status" then
 				for i, v in pairs(tagcontent) do
 					u.status[i] = v
 				end
+			elseif tagname == "set_variable" then
+				wesnoth.wml_actions.set_variable(tagcontent, u.variables)
+			elseif tagname == "clear_variable" then
+				wesnoth.wml_actions.clear_variable(tagcontent, u.variables)
 			end
 		end
 
@@ -233,6 +239,14 @@ function wml_actions.modify_unit(cfg)
 				else
 					helper.wml_error("[modify_unit] had invalid [effect]apply_to value")
 				end
+			elseif current_tag == "set_variable" then
+				local unit = wesnoth.create_unit(wml.variables[unit_path])
+				wesnoth.wml_actions.set_variable(current_table[2], unit.variables)
+				wml.variables[unit_path] = unit.__cfg
+			elseif current_tag == "clear_variable" then
+				local unit = wesnoth.create_unit(wml.variables[unit_path])
+				wesnoth.wml_actions.clear_variable(current_table[2], unit.variables)
+				wml.variables[unit_path] = unit.__cfg
 			else
 				if replace_mode then
 					wml.variables[string.format("%s.%s", unit_path, current_tag)] = {}

data/lua/wml/set_variable.lua

@@ -1,54 +1,55 @@
 local helper = wesnoth.require "helper"
 
-function wesnoth.wml_actions.set_variable(cfg)
+function wesnoth.wml_actions.set_variable(cfg, variables)
-	local name = cfg.name or helper.wml_error "trying to set a variable with an empty name"
+	local name = cfg.name or wml.error "trying to set a variable with an empty name"
+	if variables == nil then variables = wml.variables end
 
 	if cfg.value ~= nil then -- check for nil because user may try to set a variable as false
-		wml.variables[name] = cfg.value
+		variables[name] = cfg.value
 	end
 
 	if cfg.literal ~= nil then
-		wml.variables[name] = wml.shallow_literal(cfg).literal
+		variables[name] = wml.shallow_literal(cfg).literal
 	end
 
 	if cfg.to_variable then
-		wml.variables[name] = wml.variables[cfg.to_variable]
+		variables[name] = variables[cfg.to_variable]
 	end
 
 	if cfg.suffix then
-		wml.variables[name] = (wml.variables[name] or '') .. (cfg.suffix or '')
+		variables[name] = (variables[name] or '') .. (cfg.suffix or '')
 	end
 
 	if cfg.prefix then
-		wml.variables[name] = (cfg.prefix or '') .. (wml.variables[name] or '')
+		variables[name] = (cfg.prefix or '') .. (variables[name] or '')
 	end
 
 	if cfg.add then
-		wml.variables[name] = (tonumber(wml.variables[name]) or 0) + (tonumber(cfg.add) or 0)
+		variables[name] = (tonumber(variables[name]) or 0) + (tonumber(cfg.add) or 0)
 	end
 
 	if cfg.sub then
-		wml.variables[name] = (tonumber(wml.variables[name]) or 0) - (tonumber(cfg.sub) or 0)
+		variables[name] = (tonumber(variables[name]) or 0) - (tonumber(cfg.sub) or 0)
 	end
 
 	if cfg.multiply then
-		wml.variables[name] = (tonumber(wml.variables[name]) or 0) * (tonumber(cfg.multiply) or 0)
+		variables[name] = (tonumber(variables[name]) or 0) * (tonumber(cfg.multiply) or 0)
 	end
 
 	if cfg.divide then
 		local divide = tonumber(cfg.divide) or 0
-		if divide == 0 then helper.wml_error("division by zero on variable " .. name) end
+		if divide == 0 then wml.error("division by zero on variable " .. name) end
-		wml.variables[name] = (tonumber(wml.variables[name]) or 0) / divide
+		variables[name] = (tonumber(variables[name]) or 0) / divide
 	end
 
 	if cfg.modulo then
 		local modulo = tonumber(cfg.modulo) or 0
-		if modulo == 0 then helper.wml_error("division by zero on variable " .. name) end
+		if modulo == 0 then wml.error("division by zero on variable " .. name) end
-		wml.variables[name] = (tonumber(wml.variables[name]) or 0) % modulo
+		variables[name] = (tonumber(variables[name]) or 0) % modulo
 	end
 
 	if cfg.abs then
-		wml.variables[name] = math.abs(tonumber(wml.variables[name]) or 0)
+		variables[name] = math.abs(tonumber(variables[name]) or 0)
 	end
 
 	if cfg.root then
@@ -64,40 +65,40 @@ function wesnoth.wml_actions.set_variable(cfg)
 			root_fcn = function(n) return n ^ (1 / root) end
 		end
 
-		local radicand = tonumber(wml.variables[name]) or 0
+		local radicand = tonumber(variables[name]) or 0
 		if radicand < 0 and root % 2 == 0 then
 			if root == 2 then
-				helper.wml_error("square root of negative number on variable " .. name)
+				wml.error("square root of negative number on variable " .. name)
 			else
-				helper.wml_error(string.format("%dth root of negative number on variable %s", root, name))
+				wml.error(string.format("%dth root of negative number on variable %s", root, name))
 			end
 		end
 
-		wml.variables[name] = root_fcn(radicand)
+		variables[name] = root_fcn(radicand)
 	end
 
 	if cfg.power then
-		wml.variables[name] = (tonumber(wml.variables[name]) or 0) ^ (tonumber(cfg.power) or 0)
+		variables[name] = (tonumber(variables[name]) or 0) ^ (tonumber(cfg.power) or 0)
 	end
 
 	if cfg.round then
-		local var = tonumber(wml.variables[name] or 0)
+		local var = tonumber(variables[name] or 0)
 		local round_val = cfg.round
 		if round_val == "ceil" then
-			wml.variables[name] = math.ceil(var)
+			variables[name] = math.ceil(var)
 		elseif round_val == "floor" then
-			wml.variables[name] = math.floor(var)
+			variables[name] = math.floor(var)
 		elseif round_val == "trunc" then
 			-- Storing to a variable first because modf returns two values,
 			-- and I'm not sure if set_variable will complain about the extra parameter
 			local new_val = math.modf(var)
-			wml.variables[name] = new_val
+			variables[name] = new_val
 		else
 			local decimals = math.modf(tonumber(round_val) or 0)
 			local value = var * (10 ^ decimals)
 			value = helper.round(value)
 			value = value * (10 ^ -decimals)
-			wml.variables[name] = value
+			variables[name] = value
 		end
 	end
 
@@ -106,36 +107,36 @@ function wesnoth.wml_actions.set_variable(cfg)
 	-- but on the value assigned to the respective key
 	if cfg.ipart then
 		local ivalue = math.modf(tonumber(cfg.ipart) or 0)
-		wml.variables[name] = ivalue
+		variables[name] = ivalue
 	end
 
 	if cfg.fpart then
 		local ivalue, fvalue = math.modf(tonumber(cfg.fpart) or 0)
-		wml.variables[name] = fvalue
+		variables[name] = fvalue
 	end
 
 	if cfg.string_length ~= nil then
-		wml.variables[name] = string.len(tostring(cfg.string_length))
+		variables[name] = string.len(tostring(cfg.string_length))
 	end
 
 	if cfg.time then
 		if cfg.time == "stamp" then
-			wml.variables[name] = wesnoth.get_time_stamp()
+			variables[name] = wesnoth.get_time_stamp()
 		end
 	end
 
 	if cfg.rand then
-		wml.variables[name] = helper.rand(tostring(cfg.rand))
+		variables[name] = helper.rand(tostring(cfg.rand))
 	end
 
 	if cfg.formula then
 		local fcn = wesnoth.compile_formula(cfg.formula)
-		wml.variables[name] = fcn(wml.variables[name])
+		variables[name] = fcn(variables[name])
 	end
 
 	local join_child = wml.get_child(cfg, "join")
 	if join_child then
-		local array_name = join_child.variable or helper.wml_error "missing variable= attribute in [join]"
+		local array_name = join_child.variable or wml.error "missing variable= attribute in [join]"
 		local separator = join_child.separator
 		local key_name = join_child.key or "value"
 		local remove_empty = join_child.remove_empty
@@ -151,6 +152,6 @@ function wesnoth.wml_actions.set_variable(cfg)
 			end
 		end
 
-		wml.variables[name] = string_to_join
+		variables[name] = string_to_join
 	end
 end

src/scripting/lua_team.cpp

@@ -40,6 +40,7 @@
 
 // Registry key
 static const char * Team = "side";
+static const char teamVar[] = "side variables";
 
 /**
  * Gets some data on a side (__index metamethod).
@@ -102,6 +103,13 @@ static int impl_side_get(lua_State *L)
 		}
 		return 1;
 	}
+	if(strcmp(m, "variables") == 0) {
+		lua_createtable(L, 1, 0);
+		lua_pushvalue(L, 1);
+		lua_rawseti(L, -2, 1);
+		luaL_setmetatable(L, teamVar);
+		return 1;
+	}
 
 	// These are blocked together because they are all part of the team_data struct.
 	// Some of these values involve iterating over the units map to calculate them.
@@ -212,10 +220,67 @@ static int impl_side_equal(lua_State *L)
 	return 1;
 }
 
+/**
+ * Gets the variable of a side (__index metamethod).
+ * - Arg 1: table containing the userdata containing the side id.
+ * - Arg 2: string containing the name of the status.
+ * - Ret 1: boolean.
+ */
+static int impl_side_variables_get(lua_State *L)
+{
+	if(!lua_istable(L, 1)) {
+		return luaW_type_error(L, 1, "side variables");
+	}
+	lua_rawgeti(L, 1, 1);
+	const team& side = luaW_checkteam(L, -1);
+	
+	char const *m = luaL_checkstring(L, 2);
+	return_cfgref_attrib("__cfg", side.variables());
+
+	variable_access_const v(m, side.variables());
+	return luaW_pushvariable(L, v) ? 1 : 0;
+}
+
+/**
+ * Sets the variable of a side (__newindex metamethod).
+ * - Arg 1: table containing the userdata containing the side id.
+ * - Arg 2: string containing the name of the status.
+ * - Arg 3: scalar.
+ */
+static int impl_side_variables_set(lua_State *L)
+{
+	if(!lua_istable(L, 1)) {
+		return luaW_type_error(L, 1, "side variables");
+	}
+	lua_rawgeti(L, 1, 1);
+	team& side = luaW_checkteam(L, -1);
+	
+	char const *m = luaL_checkstring(L, 2);
+	if(strcmp(m, "__cfg") == 0) {
+		side.variables() = luaW_checkconfig(L, 3);
+		return 0;
+	}
+	config& vars = side.variables();
+	if(lua_isnoneornil(L, 3)) {
+		try {
+			variable_access_throw(m, vars).clear(false);
+		} catch(const invalid_variablename_exception&) {
+		}
+		return 0;
+	}
+	variable_access_create v(m, vars);
+	luaW_checkvariable(L, v, 3);
+	return 0;
+}
+
 namespace lua_team {
 
 	std::string register_metatable(lua_State * L)
 	{
+		std::ostringstream cmd_out;
+
+		cmd_out << "Adding getside metatable...\n";
+		
 		luaL_newmetatable(L, Team);
 
 		static luaL_Reg const callbacks[] {
@@ -232,7 +297,18 @@ namespace lua_team {
 		luaW_getglobal(L, "wesnoth", "match_side");
 		lua_setfield(L, -2, "matches");
 
-		return "Adding getside metatable...\n";
+		// Create the side variables metatable.
+		cmd_out << "Adding side variables metatable...\n";
+
+		luaL_newmetatable(L, teamVar);
+		lua_pushcfunction(L, impl_side_variables_get);
+		lua_setfield(L, -2, "__index");
+		lua_pushcfunction(L, impl_side_variables_set);
+		lua_setfield(L, -2, "__newindex");
+		lua_pushstring(L, "side variables");
+		lua_setfield(L, -2, "__metatable");
+		
+		return cmd_out.str();
 	}
 }