added save/discard/back menu for saving changes

functions.lua

@@ -1697,10 +1697,113 @@ yl_speak_up.add_new_dialog = function(dialog, pname)
 	return future_d_id
 end
 
+
+-- this is always called when switching to a new dialog; but only in edit_mode does
+-- it show a formspec asking for change/back/discard
+yl_speak_up.save_changes_and_switch_to_other_dialog = function(player, fields, target_dialog)
+
+	if(not(target_dialog)) then
+		target_dialog = ""
+	end
+
+	local pname = player:get_player_name()
+	-- if the player is not even talking to this particular npc
+	if(not(yl_speak_up.speak_to[pname])) then
+		return
+	end
+
+	local edit_mode = (yl_speak_up.edit_mode[pname] == yl_speak_up.speak_to[pname].n_id)
+	local d_id = yl_speak_up.speak_to[pname].d_id
+	local n_id = yl_speak_up.speak_to[pname].n_id
+
+	-- the player decided to go back and continue editing the current dialog
+	if(edit_mode and fields.back_to_dialog_changes) then
+		-- do NOT clear the list of changes; just show the old dialog again
+		minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, n_id, d_id))
+		return
+
+	-- save changes and continue on to the next dialog
+	elseif(edit_mode and fields.save_dialog_changes) then
+		-- actually save the dialog (the one the NPC currently has)
+		save_dialog(n_id, yl_speak_up.speak_to[pname].dialog)
+		-- clear list of changes
+		yl_speak_up.npc_was_changed[ n_id ] = {}
+
+	-- discard changes and continue on to the next dialog
+	elseif(edit_mode and fields.discard_dialog_changes) then
+		-- actually restore the old state and discard the changes by loading the dialog anew
+		yl_speak_up.speak_to[pname].dialog = load_dialog(n_id)
+		-- clear list of changes
+		yl_speak_up.npc_was_changed[ n_id ] = {}
+	end
+
+	-- are there any changes which might be saved or discarded?
+	if(edit_mode
+	  and  yl_speak_up.npc_was_changed[ n_id ]
+	  and #yl_speak_up.npc_was_changed[ n_id ] > 0) then
+
+		local target_name = "quit"
+		if(target_dialog and target_dialog ~= "") then
+			target_name = "go on to dialog "..minetest.formspec_escape(target_dialog)
+		end
+
+		local d_id = yl_speak_up.speak_to[pname].d_id
+		-- reverse the order of the changes in the log so that newest are topmost
+		local text = ""
+		for i,t in ipairs(yl_speak_up.npc_was_changed[ n_id ]) do
+			-- some entries may be more than one line long
+			local tmp = ""
+			local parts = string.split(t, "\n", false)
+			for i, part in ipairs(parts) do
+				tmp = tmp..minetest.formspec_escape(part)..","
+			end
+			text = tmp..text
+		end
+		-- build a formspec showing the changes to this dialog and ask for save
+		local formspec =
+			"formspec_version[3]"..
+			"size[14,6.2]"..
+			"bgcolor[#00000000;false]"..
+			"label[0.2,0.2;You are about to leave dialog "..minetest.formspec_escape(d_id)..
+				" and "..target_name..".]"..
+			"label[0.2,0.65;These changes have been applied to dialog "..
+				minetest.formspec_escape(d_id)..":]"..
+			"textlist[0.2,1;13.5,4;list_of_changes;"..text.."]"..
+			"button[1.2,5.2;3,0.9;discard_dialog_changes;Discard changes]"..
+			"button[5.7,5.2;3,0.9;back_to_dialog_changes;Back]"..
+			"button[10.2,5.2;3,0.9;save_dialog_changes;Save changes]"..
+			"tooltip[save_dialog_changes;Save all changes to this dialog and "..target_name..".]"..
+			"tooltip[discard_dialog_changes;Undo all changes and "..target_name..".]"..
+			"tooltip[back_to_dialog_changes;Go back to dialog "..
+				minetest.formspec_escape(d_id).." and continue editing it.]"..
+
+			-- hidden field telling about the target dialog
+			"field[20,20;0.1,0.1;goto_target_dialog;target_dialog;"..minetest.formspec_escape(target_dialog).."]"
+		-- actaully show the formspec to the player
+		minetest.show_formspec(pname, "yl_speak_up:confirm_save", formspec)
+		return
+	end
+	-- if there is nothing that needs to be saved or discarded: allow quit/exit
+        if fields.quit or fields.button_exit then
+		yl_speak_up.edit_mode[pname] = nil
+		-- Formspec was quit
+		yl_speak_up.speak_to[pname] = nil
+		return
+	end
+	-- end edit mode and start a new chat - but this time in normal mode
+	if not(target_dialog) or target_dialog == "" then
+		yl_speak_up.edit_mode[pname] = nil
+		target_dialog = nil
+	end
+	-- move on to the target dialog
+	yl_speak_up.speak_to[pname].d_id = target_dialog
+	minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, n_id, target_dialog))
+end
+
+
 -- helper function for formspec "yl_speak_up:talk" when a parameter was changed in edit mode;
 -- this is called when the player is in edit_mode (editing the NPC);
 -- the function checks if the player has changed any parameters
--- TODO: implement the change detection and ask the user what to do (save? discard?)
 -- Parameters:
 --    pname    player name
 --    fields   the fields returned from the formspec
@@ -1820,15 +1923,19 @@ yl_speak_up.edit_mode_apply_changes = function(pname, fields)
 		fields["d_id"] = d_id
 		fields["show_new_dialog"] = nil
 	end
-
-	-- TODO just for debugging
-	for k,v in pairs(yl_speak_up.npc_was_changed[ yl_speak_up.edit_mode[pname] ]) do
-		minetest.chat_send_player(pname, v )
-	end
 end
 -- end of yl_speak_up.edit_mode_apply_changes
 
 
+minetest.register_on_player_receive_fields(
+    function(player, formname, fields)
+	if formname ~= "yl_speak_up:confirm_save" then
+		return
+	end
+	yl_speak_up.save_changes_and_switch_to_other_dialog(player, fields, fields.goto_target_dialog)
+    end
+)
+
 
 minetest.register_on_player_receive_fields(
     function(player, formname, fields)
@@ -1865,16 +1972,14 @@ minetest.register_on_player_receive_fields(
 	    return
         -- end edit mode (does not require the priv; will only switch back to normal behaviour)
         elseif fields.button_end_edit_mode then
-            yl_speak_up.edit_mode[pname] = nil
-	    -- start a new chat - but this time in normal mode
-            yl_speak_up.speak_to[pname].d_id = nil
-            minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, yl_speak_up.speak_to[pname].n_id, nil))
+            -- if there are any changes done: ask first and don't end edit mode yet
+            yl_speak_up.save_changes_and_switch_to_other_dialog(player, fields, nil)
 	    return
        end
 
         if fields.quit or fields.button_exit then
-            -- Formspec was quit
-            yl_speak_up.speak_to[pname] = nil
+            -- if there are any changes done: ask first and don't quit yet
+            yl_speak_up.save_changes_and_switch_to_other_dialog(player, fields, nil)
             return
         end
 
@@ -1948,8 +2053,8 @@ minetest.register_on_player_receive_fields(
 	            end
 	        end
 	    end
-            yl_speak_up.speak_to[pname].d_id = show_dialog
-            minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, yl_speak_up.speak_to[pname].n_id, show_dialog))
+            -- if there are any changes done: ask first and don't switch to the new dialog yet
+            yl_speak_up.save_changes_and_switch_to_other_dialog(player, fields, show_dialog)
 	    return
 	end
 
@@ -2079,9 +2184,9 @@ minetest.register_on_player_receive_fields(
                 end
                 if v.r_type == "dialog" then
                     if dialog.n_dialogs[v.r_value] ~= nil then
-                        yl_speak_up.speak_to[pname].d_id = v.r_value
-                        local n_id = yl_speak_up.speak_to[pname].n_id
-                        minetest.show_formspec(pname, "yl_speak_up:talk", get_fs_talkdialog(player, n_id, v.r_value))
+                        -- if there are any changes done: ask first and don't switch to the new dialog yet
+			yl_speak_up.save_changes_and_switch_to_other_dialog(player, fields, v.r_value)
+	                return
                     else
                         say("This dialog does not exist")
                     end