made edit dialog work in formspec versions < 3 as far as possible

fs_talkdialog.lua

@@ -276,6 +276,24 @@ yl_speak_up.input_talk = function(player, formname, fields)
 end
 
 
+-- older formspecs (before v3) do not offer a scroll container and have to scroll manually;
+-- we maintain a player-name-based counter in order to see if this line ought to be shown
+yl_speak_up.old_fs_version_show_line = function(pname)
+	-- the player is using a new enough version for scroll_container to work
+	if(not(pname)) then
+		return true
+	end
+	local max_number_of_buttons = yl_speak_up.max_number_of_buttons
+	local start_index = yl_speak_up.speak_to[pname].option_index
+	local counter = yl_speak_up.speak_to[pname].counter
+	yl_speak_up.speak_to[pname].counter = counter + 1
+	if counter < start_index or counter >= start_index + max_number_of_buttons then
+		return false
+	end
+	return true
+end
+
+
 -- show an edit option in the main menu of the NPC;
 -- helper function for yl_speak_up.fs_talkdialog(..)
 yl_speak_up.add_edit_button_fs_talkdialog = function(formspec, h, button_name, tooltip, label,
@@ -289,11 +307,7 @@ yl_speak_up.add_edit_button_fs_talkdialog = function(formspec, h, button_name, t
 	local label_start_pos = "0.7"
 	-- older formspecs (before v4) do not offer a scroll container and have to scroll manually
 	if(pname) then
-		local max_number_of_buttons = yl_speak_up.max_number_of_buttons
+		if(not(yl_speak_up.old_fs_version_show_line(pname))) then
-		local start_index = yl_speak_up.speak_to[pname].option_index
-		local counter = yl_speak_up.speak_to[pname].counter
-		yl_speak_up.speak_to[pname].counter = counter + 1
-		if counter < start_index or counter >= start_index + max_number_of_buttons then
 			return h
 		end
 		-- there has to be more room for the up and down arrows
@@ -657,11 +671,17 @@ yl_speak_up.get_fs_talkdialog = function(player, n_id, d_id, alternate_text, rec
             for _, sb_v in pairs(sorted_buttons) do
 		local oid = minetest.formspec_escape(sb_v.o_id)
                 -- in edit_mode: show all options
-		if edit_mode then
+		if(edit_mode and yl_speak_up.old_fs_version_show_line(pname_for_old_fs)) then
-                    h = h + 1
+			local offset = 0.0
+			local field_length = 44.4
+			if(pname_for_old_fs) then
+				offset = 0.7
+				field_length = 42.4
+			end
+			h = h + 1
 			-- add a button "o_<nr>:" that leads to an edit formspec for this option
 			yl_speak_up.add_formspec_element_with_tooltip_if(formspec,
-				"button", "2.3," .. h .. ";2,0.9", "edit_option_" .. oid,
+				"button", tostring(2.3+offset).."," .. h .. ";2,0.9", "edit_option_" .. oid,
 				oid,
 				"Edit target dialog, pre(C)onditions and (Ef)fects for option "..oid..".",
 				true)
@@ -683,16 +703,17 @@ yl_speak_up.get_fs_talkdialog = function(player, n_id, d_id, alternate_text, rec
 		        -- add a button "-> d_<nr>" that leads to the target dialog (if one is set)
 			-- selecting an option this way MUST NOT execute the pre(C)onditions or (Ef)fects!
 			yl_speak_up.add_formspec_element_with_tooltip_if(formspec,
-				"button", "9.0," .. h .. ";1,0.9", "button_" .. oid,
+				"button", tostring(9.0+offset).."," .. h .. ";1,0.9", "button_" .. oid,
 				"->",
-				"Go to target dialog "..minetest.formspec_escape(target_dialog)..
+				"Go to target dialog "..minetest.formspec_escape(target_dialog or "")..
 					" that will be shown when this option ("..oid..") is selected.",
 				(target_dialog))
 
 			-- allow to set a new target dialog
-			table.insert(formspec, "dropdown[4.4,"..h..";4.7,1;d_id_"..oid..";"..
+			table.insert(formspec, "dropdown["..tostring(4.4+offset)..","..h..";4.7,1;d_id_"..
+					oid..";"..
 				dialog_list..";"..
-				minetest.formspec_escape(d_id_to_dropdown_index[target_dialog] or "0")..",]")
+				minetest.formspec_escape(d_id_to_dropdown_index[(target_dialog or "?")] or "0")..",]")
 			-- add a tooltip "Change target dialog"
 			table.insert(formspec, "tooltip[4.4,"..h..";4.7,1;"..
 				"Change target dialog for option "..oid..".;#FFFFFF;#000000]")
@@ -700,13 +721,13 @@ yl_speak_up.get_fs_talkdialog = function(player, n_id, d_id, alternate_text, rec
 			-- are there any prerequirements?
 			local prereq = active_dialog.d_options[sb_v.o_id].o_prerequisites
 			yl_speak_up.add_formspec_element_with_tooltip_if(formspec,
-				"button", "0.5," .. h .. ";0.5,0.9", "conditions_"..oid,
+				"button", tostring(0.5+offset).."," .. h .. ";0.5,0.9", "conditions_"..oid,
 				"C",
 				"There are pre(C)onditions required for showing this option. Display them.",
 				(prereq and next(prereq)))
 
 			yl_speak_up.add_formspec_element_with_tooltip_if(formspec,
-				"button", "1.6," .. h .. ";0.6,0.9", "effects_"..oid,
+				"button", tostring(1.6+offset).."," .. h .. ";0.6,0.9", "effects_"..oid,
 				"Ef",
 				"There are further (Ef)fects (apart from switching\n"..
 					"to a new dialog) set for this option. Display them.",
@@ -715,7 +736,7 @@ yl_speak_up.get_fs_talkdialog = function(player, n_id, d_id, alternate_text, rec
 			-- are there any actions defined?
 			local actions = active_dialog.d_options[sb_v.o_id].actions
 			yl_speak_up.add_formspec_element_with_tooltip_if(formspec,
-				"button", "1.1," .. h .. ";0.5,0.9", "actions_"..oid,
+				"button", tostring(1.1+offset).."," .. h .. ";0.5,0.9", "actions_"..oid,
 				"A",
 				"There is an (A)ction (i.e. a trade) that will happen\n"..
 					"when switching to a new dialog. Display actions and\n"..
@@ -724,13 +745,15 @@ yl_speak_up.get_fs_talkdialog = function(player, n_id, d_id, alternate_text, rec
 
 			-- show the actual text for the option
 			yl_speak_up.add_formspec_element_with_tooltip_if(formspec,
-				"field", "9.9," .. h .. ";44.4,0.9", "text_option_" .. oid,
+				"field", tostring(9.9+offset).."," .. h .. ";"..
+					 tostring(field_length)..",0.9",
+				"text_option_" .. oid,
 				";"..minetest.formspec_escape(sb_v.o_text_when_prerequisites_met),
 				"Edit the text that is displayed on button "..oid..".",
 				true)
 
 		-- normal mode: show an option if the prerequirements (if any are defined) are met
-		else
+		elseif(not(edit_mode)) then
 			local t = "- no text given -"
 			local t_alt = nil
 			-- the preconditions are fulfilled; showe the option