-- client.lua
-- AE2-Client, empfängt Daten per rednet und zeigt AE2 UI an

-------------------------
-- 1) KONFIG
-------------------------
local monSide     = "right"      -- Monitor-Seite
local modemSide   = "top"       -- Wireless Modem-Seite
local BOX_W       = 14           -- Breite Kästchen
local BOX_H       = 4            -- Höhe Kästchen
local ITEMS_PER_PAGE   = 10      -- Items in Detailansicht
local REDNET_PROTOCOL  = "AE2_DATA"  -- Muss zum Server passen
local DATA_TIMEOUT     = 15      -- Sekunden, bis wir "keine Daten" anzeigen

-------------------------
-- 2) Peripherie-Abfrage
-------------------------
local mon = peripheral.wrap(monSide)
if not mon then
  error("Monitor an Seite '"..monSide.."' nicht gefunden!")
end

local modem = peripheral.wrap(modemSide)
if not modem then
  error("Modem an Seite '"..modemSide.."' nicht gefunden!")
end
rednet.open(modemSide)

mon.setTextScale(0.5)

-------------------------
-- 3) Globale Variablen
-------------------------
local width, height = mon.getSize()
local currentScreen = "main"
local currentPage   = 1

-- Daten vom Server
local serverData = {
  cells       = {},  -- { {usedBytes=..., totalBytes=...}, ... }
  itemCount   = 0,
  freePercent = 0,
  items       = {},  -- Komplette Liste (sortiert)
}

-------------------------
-- 4) Hilfsfunktionen
-------------------------
local function clear()
  mon.setBackgroundColor(colors.black)
  mon.clear()
  mon.setCursorPos(1,1)
end

local function centerText(y, text, color)
  color = color or colors.white
  mon.setTextColor(color)
  local x = math.floor((width - #text) / 2)
  mon.setCursorPos(x+1, y)
  mon.write(text)
end

local function getColorForUsage(used, total)
  if total == 0 then
    return colors.lime
  end
  local percent = used / total
  if percent >= 0.9 then
    return colors.red
  elseif percent >= 0.5 then
    return colors.yellow
  else
    return colors.lime
  end
end

-------------------------
-- 4.1) Box-Zeichnung (Cell UI)
-------------------------
local function drawCellBox(x, y, w, h, cellIndex, usedB, totalB)
  mon.setCursorPos(x, y)
  mon.setTextColor(colors.white)
  mon.write("+")
  for i = 1, w-2 do
    mon.write("-")
  end
  mon.write("+")

  for row = 1, h-2 do
    mon.setCursorPos(x, y+row)
    mon.write("|")
    mon.setCursorPos(x+w-1, y+row)
    mon.write("|")
  end

  mon.setCursorPos(x, y+h-1)
  mon.write("+")
  for i = 1, w-2 do
    mon.write("-")
  end
  mon.write("+")

  -- Info
  mon.setCursorPos(x+1, y+1)
  mon.setTextColor(colors.white)
  mon.write("Cell "..cellIndex)

  local percent = 0
  if totalB > 0 then
    percent = math.floor((usedB / totalB)*100)
  end
  local usageColor = getColorForUsage(usedB, totalB)
  mon.setTextColor(usageColor)
  mon.setCursorPos(x+1, y+2)
  mon.write(usedB.."/"..totalB.." ("..percent.."%)")
end

-------------------------
-- 5) Hauptmenü zeichnen
-------------------------
local function drawMainScreen()
  clear()
  centerText(1, "AE2 Cells Overview (Page "..currentPage..")", colors.cyan)

  local cells = serverData.cells or {}
  local columns = math.floor(width / BOX_W)
  local rows    = math.floor((height - 3) / BOX_H)

  if columns < 1 or rows < 1 then
    centerText(math.floor(height/2), "Monitor zu klein!", colors.red)
    return
  end

  local boxesPerPage = columns * rows
  local totalCells   = #cells
  local totalPages   = math.ceil(totalCells / boxesPerPage)

  -- "globale" totalPages Updaten, damit wir blättern können
  _G.totalPages = totalPages

  local startCell = (currentPage - 1)*boxesPerPage + 1
  local endCell   = math.min(startCell + boxesPerPage - 1, totalCells)

  local idx = startCell
  for row=0, rows-1 do
    for col=0, columns-1 do
      if idx > endCell then break end
      local c = cells[idx]
      local usedB  = c.usedBytes  or 0
      local totalB = c.totalBytes or 0

      local x = col*BOX_W + 1
      local y = row*BOX_H + 2
      drawCellBox(x, y, BOX_W, BOX_H, idx, usedB, totalB)
      idx = idx + 1
    end
    if idx > endCell then break end
  end

  -- Infozeile (Cells, Items, Frei)
  mon.setCursorPos(2, height-1)
  mon.setTextColor(colors.white)
  local msg = string.format("Cells: %d  Items: %d  Frei: %d%%",
    #cells, serverData.itemCount, serverData.freePercent)
  mon.write(msg)

  -- Seitenbuttons
  mon.setCursorPos(2, height)
  if currentPage > 1 then
    mon.write("[ < ]")
  end
  mon.setCursorPos(width-5, height)
  if currentPage < totalPages then
    mon.write("[ > ]")
  end
end

-------------------------
-- 5.1) Detail-Items
-------------------------
local function drawCellDetails(cellIndex)
  clear()
  centerText(1, "Cell "..cellIndex.." - Top Items", colors.cyan)

  local items = serverData.items or {}
  local y = 3
  local shown = 0

  for _, it in ipairs(items) do
    if y >= height then break end
    mon.setCursorPos(2, y)
    mon.setTextColor(colors.white)
    mon.write((it.displayName or "?")..": "..(it.amount or 0))
    y = y + 1
    shown = shown + 1
    if shown >= ITEMS_PER_PAGE then
      break
    end
  end

  mon.setCursorPos(2, height)
  mon.setTextColor(colors.gray)
  mon.write("[ Zurueck ]")
end

-------------------------
-- 6) Klick -> Welche Cell?
-------------------------
local function getCellIndexFromClick(x, y)
  local cells = serverData.cells or {}
  local columns = math.floor(width / BOX_W)
  local rows    = math.floor((height - 3) / BOX_H)
  local boxesPerPage = columns * rows

  local totalCells = #cells
  local totalPages = math.ceil(totalCells / boxesPerPage)
  _G.totalPages = totalPages  -- for global reference

  local startCell = (currentPage - 1)*boxesPerPage + 1
  local endCell   = math.min(startCell + boxesPerPage - 1, totalCells)

  local col = math.floor((x-1)/BOX_W)
  local row = math.floor((y-2)/BOX_H)
  if col<0 or col>=columns or row<0 or row>=rows then
    return nil
  end

  local cellOffset = row*columns + col
  local actualIndex = startCell + cellOffset
  if actualIndex <= endCell then
    return actualIndex
  end
  return nil
end

-------------------------
-- 7) Haupt-Loop
-------------------------
local refreshTimer = os.startTimer(1) -- alle 1s checken, ob neue Daten reingekommen sind

-- Wir speichern Zeitstempel, wann wir zuletzt Daten erhielten
local lastDataTime = os.epoch("utc")

-- Wir zeigen init
drawMainScreen()

while true do
  local event, p1, p2, p3, p4 = os.pullEvent()

  if event == "rednet_message" then
    local senderID, message, protocol = p1, p2, p3
    if protocol == REDNET_PROTOCOL and type(message)=="table" then
      -- Neue Daten vom Server
      serverData = message
      lastDataTime = os.epoch("utc")
      if currentScreen == "main" then
        drawMainScreen()
      end
    end

  elseif event == "monitor_touch" then
    local x, y = p2, p3
    if currentScreen == "main" then
      -- Blättern?
      if y == height then
        if x>=2 and x<=5 and currentPage>1 then
          currentPage = currentPage - 1
          drawMainScreen()
        elseif x>=width-4 and x<=width and currentPage<_G.totalPages then
          currentPage = currentPage + 1
          drawMainScreen()
        end
      else
        -- Klick auf Cell => Detail
        local cellIndex = getCellIndexFromClick(x,y)
        if cellIndex then
          currentScreen = "cell"
          drawCellDetails(cellIndex)
        end
      end
    elseif currentScreen == "cell" then
      -- Klick auf [Zurueck]
      if y == height then
        currentScreen = "main"
        drawMainScreen()
      end
    end

  elseif event == "timer" then
    if p1 == refreshTimer then
      -- Prüfe, ob wir zu lange keine Daten hatten
      local now = os.epoch("utc")
      if now - lastDataTime > (DATA_TIMEOUT*1000) then
        -- Zu lange keine Daten => Anzeige leeren
        clear()
        centerText(math.floor(height/2), "Keine Daten vom Server!", colors.red)
      end
      refreshTimer = os.startTimer(1) -- Timer neu
    end
  end
end