z_mirror/MouseOverConstruction

git clone https://git.raiguard.me/z_mirror/MouseOverConstruction

Caleb HeuerWIP7a81c3d2025-10-15

--- @param box1 BoundingBox
--- @param box2 BoundingBox
local function bounding_boxes_equal(box1, box2)
  return box1.left_top.x == box2.left_top.x
    and box1.left_top.y == box2.left_top.y
    and box1.right_bottom.x == box2.right_bottom.x
    and box1.right_bottom.y == box2.right_bottom.y
end

--- @class common
local common = {}

--- Builds an entity over the top of an existing entity.
--- @param player LuaPlayer
--- @param entity LuaEntity
--- @param new_prototype LuaEntityPrototype
--- @param new_quality LuaQualityPrototype
--- @return LuaEntity?
function common.build(player, entity, new_prototype, new_quality)
  local item_spec = common.get_item_to_place(player, new_prototype, new_quality)
  if not item_spec then
    return nil
  end

  local bounding_box = entity.bounding_box
  local surface = entity.surface
  local position = entity.position
  local direction = entity.direction
  local quality = entity.quality
  local force = entity.force

  local new_entity = player.surface.create_entity({
    name = new_prototype.name,
    position = entity.position,
    direction = entity.direction,
    quality = new_quality,
    force = entity.force,
    fast_replace = true,
    player = player,
    character = player.character,
    raise_built = true,
    create_build_effect_smoke = true,
    spawn_decorations = true,
    move_stuck_players = true,
    item = item_spec.item,
    register_plant = true,
    --- Undergound belt
    type = entity.type == "underground-belt" and entity.belt_to_ground_type or nil,
  })
  if not new_entity or not new_entity.valid then
    -- Some mods will immediately replace the entity with a different one. Let's see if we can detect this.
    for _, replaced_entity in
      pairs(surface.find_entities_filtered({
        direction = direction,
        position = position,
        quality = quality.name,
        force = force,
      }))
    do
      if
        replaced_entity.type ~= "entity-ghost"
        and replaced_entity.type ~= "tile-ghost"
        and bounding_boxes_equal(replaced_entity.bounding_box, bounding_box)
      then
        new_entity = replaced_entity
        break
      else
        return
      end
    end
  end

  item_spec.item.count = item_spec.item.count - item_spec.count

  player.play_sound({
    path = "entity-build/" .. new_entity.name,
    position = new_entity.position,
  })

  return new_entity
end

--- @param player LuaPlayer
--- @param entity LuaEntity
--- @param new_prototype LuaEntityPrototype
--- @return boolean
function common.check_can_place_entity(player, entity, new_prototype)
  -- TODO: Remote interface for mods to conditionally decide if placement is allowed.
  if
    not player.can_place_entity({
      name = new_prototype.name,
      position = entity.position,
      direction = entity.direction,
    })
  then
    storage.recheck_on_move[player.index] = true
    return false
  end
  return true
end

--- @param item LuaItemStack
--- @param name string
--- @param quality LuaQualityPrototype
--- @param min_count uint?
--- @param max_count uint?
local function does_item_match(item, name, quality, min_count, max_count)
  min_count = min_count or 0
  max_count = max_count or math.huge

  return item.valid_for_read
    and item.name == name
    and item.quality == quality
    and item.count >= min_count
    and item.count <= max_count
end

--- Returns the first LuaItemStack with the given name and quality. If count is provided, the returned item stack will
--- contain at least count items.
--- @param player LuaPlayer
--- @param name string
--- @param quality LuaQualityPrototype
--- @param min_count uint?
--- @param max_count uint?
--- @return fun(): LuaItemStack?
function common.get_item(player, name, quality, min_count, max_count)
  local cursor_stack_used = false
  local cursor_stack = player.cursor_stack
  local inventory = player.get_main_inventory()
  local i = 0
  return function()
    if not cursor_stack_used then
      cursor_stack_used = true
      if cursor_stack and does_item_match(cursor_stack, name, quality, min_count, max_count) then
        return cursor_stack
      end
    end

    if not inventory then
      return
    end

    while i <= #inventory do
      i = i + 1
      local stack = inventory[i]
      if does_item_match(stack, name, quality, min_count, max_count) then
        return stack
      end
    end
  end
end

--- Returns the first LuaItemStack that can build the given entity and quality.
--- @param player LuaPlayer
--- @param prototype LuaEntityPrototype
--- @param quality LuaQualityPrototype
--- @return {item: LuaItemStack, count: uint}?
function common.get_item_to_place(player, prototype, quality)
  for _, item_to_place in pairs(prototype.items_to_place_this or {}) do
    local item = common.get_item(player, item_to_place.name, quality, item_to_place.count)()
    if item then
      return { item = item, count = item_to_place.count }
    end
  end
end

return common