local NUM_REQUEST_SLOTS = 4 -- maybe at some point make this a param, but why?
local PUSH_LIST_PICKER = "push_pick"
local ON_OFF_BUTTON = "on_off_btn"
local FORMSPEC_NAME = "logistica_requester"

local requesterForms = {}

local function get_requester_formspec(pos)
  local posForm = "nodemeta:"..pos.x..","..pos.y..","..pos.z
  local pushPos = logistica.get_requester_target(pos)
  local selectedList = logistica.get_requester_target_list(pos)
  local isOn = logistica.is_machine_on(pos)
  return "formspec_version[4]" ..
    "size[10.6,7]" ..
    logistica.ui.background..
    logistica.ui.push_list_picker(PUSH_LIST_PICKER, 6.7, 0.7, pushPos, selectedList, "Put items in:")..
    logistica.ui.on_off_btn(isOn, 9.3, 0.5, ON_OFF_BUTTON, "Enable")..
    "list["..posForm..";filter;0.5,0.5;"..NUM_REQUEST_SLOTS..",1;0]"..
    "list[current_player;main;0.5,2;8,4;0]"
end

local function show_requester_formspec(playerName, pos)
  requesterForms[playerName] = {position = pos}
  minetest.show_formspec(playerName, FORMSPEC_NAME, get_requester_formspec(pos))
end

local function on_player_receive_fields(player, formname, fields)
  if not player or not player:is_player() then return false end
  if formname ~= FORMSPEC_NAME then return false end
  local playerName = player:get_player_name()
  if not requesterForms[playerName] then return false end
  local pos = requesterForms[playerName].position
  if minetest.is_protected(pos, playerName) then return true end

  if fields.quit then
    requesterForms[playerName] = nil
  elseif fields[ON_OFF_BUTTON] then
    if not pos then return false end
    logistica.toggle_machine_on_off(pos)
    show_requester_formspec(player:get_player_name(), pos)
  elseif fields[PUSH_LIST_PICKER] then
    local selected = fields[PUSH_LIST_PICKER]
    if logistica.is_allowed_push_list(selected) then
      local pos = requesterForms[playerName].position
      if not pos then return false end
      logistica.set_requester_target_list(pos, selected)
    end
  end
  return true
end

local function on_requester_punch(pos, node, puncher, pointed_thing)
  local targetPos = logistica.get_requester_target(pos)
  if targetPos and puncher:is_player() and puncher:get_player_control().sneak then
    logistica.show_output_at(targetPos)
  end
end

local function on_requester_rightclick(pos, node, clicker, itemstack, pointed_thing)
  if not clicker or not clicker:is_player() then return end
  show_requester_formspec(clicker:get_player_name(), pos)
end

local function after_place_requester(pos, placer, itemstack, numRequestSlots)
  local meta = minetest.get_meta(pos)
  if placer and placer:is_player() then
    meta:set_string("owner", placer:get_player_name())
  end
  logistica.set_requester_target_list(pos, "main")
  local inv = meta:get_inventory()
  inv:set_size("filter", numRequestSlots)
  inv:set_size("actual", numRequestSlots)
  logistica.on_requester_change(pos)
  logistica.start_requester_timer(pos)
  logistica.show_output_at(logistica.get_requester_target(pos))
end

local function allow_requester_storage_inv_put(pos, listname, index, stack, player)
  if listname ~= "filter" then return 0 end
  if minetest.is_protected(pos, player:get_player_name()) then return 0 end
  local inv = minetest.get_meta(pos):get_inventory()
  local slotStack = inv:get_stack(listname, index)
  slotStack:add_item(stack)
  inv:set_stack(listname, index, slotStack)
  logistica.update_cache_at_pos(pos, LOG_CACHE_REQUESTER)
  logistica.start_requester_timer(pos, 1)
  return 0
end

local function allow_requester_inv_take(pos, listname, index, stack, player)
  if listname ~= "filter" then return 0 end
  if minetest.is_protected(pos, player:get_player_name()) then return 0 end
  local inv = minetest.get_meta(pos):get_inventory()
  local slotStack = inv:get_stack(listname, index)
  slotStack:take_item(stack:get_count())
  inv:set_stack(listname, index, slotStack)
  logistica.update_cache_at_pos(pos, LOG_CACHE_REQUESTER)
  return 0
end

local function allow_requester_inv_move(_, _, _, _, _, _, _)
  return 0
end

----------------------------------------------------------------
-- Minetest registration
----------------------------------------------------------------

minetest.register_on_player_receive_fields(on_player_receive_fields)

----------------------------------------------------------------
-- Public Registration API
----------------------------------------------------------------
-- `simpleName` is used for the description and for the name (can contain spaces)
-- transferRate is how many items per tick this requester can transfer, -1 for unlimited
function logistica.register_requester(description, name, transferRate, tiles)
  local lname = string.lower(name:gsub(" ", "_"))
  local requester_name = "logistica:requester_"..lname
  logistica.requesters[requester_name] = true
  local grps = {oddly_breakable_by_hand = 3, cracky = 3 }
  grps[logistica.TIER_ALL] = 1
  local def = {
    description = description,
    drawtype = "normal",
    tiles = tiles,
    paramtype = "light",
    paramtype2 = "facedir",
    is_ground_content = false,
    groups = grps,
    drop = requester_name,
    sounds = logistica.node_sound_metallic(),
    on_timer = logistica.on_timer_powered(logistica.on_requester_timer),
    after_place_node = function (pos, placer, itemstack)
      after_place_requester(pos, placer, itemstack, NUM_REQUEST_SLOTS)
    end,
    after_destruct = logistica.on_requester_change,
    on_punch = on_requester_punch,
    on_rightclick = on_requester_rightclick,
    allow_metadata_inventory_put = allow_requester_storage_inv_put,
    allow_metadata_inventory_take = allow_requester_inv_take,
    allow_metadata_inventory_move = allow_requester_inv_move,
    logistica = {
      requester_transfer_rate = transferRate,
      on_connect_to_network = function(pos, networkId)
        logistica.start_requester_timer(pos)
      end,
      on_power = function(pos, isPoweredOn)

        if isPoweredOn then
          logistica.start_requester_timer(pos)
        end
      end,
    }
  }

  minetest.register_node(requester_name, def)

  local def_disabled = table.copy(def)
  local tiles_disabled = {}
  for k, v in pairs(def.tiles) do tiles_disabled[k] = v.."^logistica_disabled.png" end

  def_disabled.tiles = tiles_disabled
  def_disabled.groups = { oddly_breakable_by_hand = 3, cracky = 3, choppy = 3, not_in_creative_inventory = 1 }
  def_disabled.on_construct = nil
  def_disabled.after_destruct = nil
  def_disabled.on_punch = nil
  def_disabled.on_rightclick = nil
  def_disabled.on_timer = nil
  def_disabled.logistica = nil

  minetest.register_node(requester_name.."_disabled", def_disabled)

end

local function get_tiles(lname) return {
  "logistica_"..lname.."_requester_side.png^[transformR270",
  "logistica_"..lname.."_requester_side.png^[transformR90",
  "logistica_"..lname.."_requester_side.png^[transformR180",
  "logistica_"..lname.."_requester_side.png",
  "logistica_"..lname.."_requester_back.png",
  "logistica_"..lname.."_requester_front.png",
} end

logistica.register_requester("Item Request Inserter\nInserts 1 item at a time", "item", 1, get_tiles("item"))
logistica.register_requester("Bulk Request Inserter\nInserts up to 64 items at a time", "stack", 64, get_tiles("stack"))