Full undo (rewind)

1 files changed, 8 insertions, 12 deletions

diff --git a/main.lua b/main.lua
index c3d1199..3391780 100644
--- a/main.lua
+++ b/main.lua
@@ -66,9 +66,7 @@ end
 
 -- set current level based on the index in the levels table
 function set_level(number)
-    level_undo = {}
-    level_undo_x = 0
-    level_undo_y = 0
+    state_undo = {}
 
     level = {}
     for y, row in ipairs(levels[number]) do
@@ -154,9 +152,7 @@ function move(target_x, target_y)
     moves = moves + 1
 
     -- save the previous move for UNDO
-    level_undo = undo
-    level_undo_x = undo_x
-    level_undo_y = undo_y
+    table.insert(state_undo, 1, {undo, undo_x, undo_y})
 end
 
 -- keypressed handler when the level is compplete
@@ -180,12 +176,12 @@ function keypressed_play(key)
         -- reset level
         set_level(current_level)
         return
-    elseif key == "u" and #level_undo > 0 then
+    elseif key == "u" and #state_undo > 0 then
         -- undo move
-        level = level_undo
-        player_x = level_undo_x
-        player_y = level_undo_y
-        level_undo = {}
+        local state = table.remove(state_undo, 1)
+        level = state[1]
+        player_x = state[2]
+        player_y = state[3]
         moves = moves - 1
     end
 
@@ -252,7 +248,7 @@ function love.draw()
         love.graphics.print("R:restart", 20, 205 * game.scale)
 
         -- change colour if there's not undo
-        if #level_undo == 0 then
+        if #state_undo == 0 then
             love.graphics.setColor(0.5, 0.3, 0.3)
         end
         love.graphics.print("U:undo", 20 + 10 * 8 * game.scale, 205 * game.scale)