stage 3

src/main.lua

@@ -24,6 +24,13 @@ end
 
 -- returns cargo_amount (actual amount transferred)
 local function transfer_cargo(source_object, destination_object, cargo_type, cargo_amount)
+  if not source_object then
+    source_object = { cargo_contents = { [cargo_type] = math.huge }, cargo_free_space = 0, }
+  end
+  if not destination_object then
+    destination_object = { cargo_contents = {}, cargo_free_space = math.huge, }
+  end
+
   if not source_object.cargo_contents[cargo_type] then
     return 0
   end
@@ -31,7 +38,13 @@ local function transfer_cargo(source_object, destination_object, cargo_type, car
     destination_object.cargo_contents[cargo_type] = 0
   end
 
-  cargo_amount = math.min(cargo_amount, source_object.cargo_contents[cargo_type])
+  if cargo_amount > source_object.cargo_contents[cargo_type] then
+    cargo_amount = source_object.cargo_contents[cargo_type]
+  end
+  if cargo_amount > destination_object.cargo_free_space then
+    cargo_amount = destination_object.cargo_free_space
+  end
+
   destination_object.cargo_contents[cargo_type] = destination_object.cargo_contents[cargo_type] + cargo_amount
   destination_object.cargo_free_space = destination_object.cargo_free_space - cargo_amount
   source_object.cargo_contents[cargo_type] = source_object.cargo_contents[cargo_type] - cargo_amount
@@ -44,12 +57,25 @@ local function transfer_cargo(source_object, destination_object, cargo_type, car
   return cargo_amount
 end
 
+local function check_cargo_amount(source_object, cargo_type, cargo_amount)
+  if not source_object.cargo_contents[cargo_type] then
+    return false
+  end
+  if source_object.cargo_contents[cargo_type] >= cargo_amount then
+    return true
+  end
+  return false
+end
+
 -- The resources collected by the player can be spent on something,
 -- like improving the ship. Speed, capacity, collection speed, etc.
 -- TODO future upgrade: range upgrade ?
 --  right now: iron -> caoacity, copper -> acceleration
 
 local cargo_types = { "iron ore", "copper ore", }
+-- for i = 1, #cargo_types do
+--   cargo_types[cargo_types[i]] = i
+-- end
 
 -- TODO review my previous orbits code to add extremely slow background orbits to this
 --       planets/stars/stations always have fixed orbits; ships have a fixed orbital acceleration but have their own additional
@@ -90,7 +116,7 @@ local function spawn_3_points()
       -- NOTE can select literally anything
       local selected_type = cargo_types[math.random(#cargo_types)]
       local cargo_amount = math.random() * 10000
-      transfer_cargo({ cargo_contents = { [selected_type] = cargo_amount, }, cargo_free_space = 0, }, current_point, selected_type, cargo_amount)
+      transfer_cargo(nil, current_point, selected_type, cargo_amount)
 
       local closest_object, distance_squared_to_object = get_closest_object(resource_points, current_point)
       if closest_object and distance_squared_to_object <= (closest_object.radar_size^2 + current_point.radar_size^2) * 1.5 then
@@ -202,5 +228,22 @@ end
 function love.keypressed(key)
   if key == "escape" then
     love.event.quit()
+  elseif key == "1" then
+    -- 25x iron ore -> 5 cargo space
+    if not check_cargo_amount(player_ship, "iron ore", 25) then
+      last_message = "You do not have enough iron ore to upgrade your cargo space. (need 25)"
+      return
+    end
+    transfer_cargo(player_ship, nil, "iron ore", 25)
+    player_ship.cargo_max_space = player_ship.cargo_max_space + 5
+    player_ship.cargo_free_space = player_ship.cargo_free_space + 5
+  elseif key == "2" then
+    -- 25x copper ore -> 1.1x acceleration
+    if not check_cargo_amount(player_ship, "copper ore", 25) then
+      last_message = "You do not have enough copper ore to upgrade your acceleration. (need 25)"
+      return
+    end
+    transfer_cargo(player_ship, nil, "copper ore", 25)
+    player_ship.acceleration = player_ship.acceleration * 1.1
   end
 end