-- private variables
local SHOP_EXTENTED_OPCODE = 201

shop = nil
local shopButton = nil
local msgWindow = nil
local browsingHistory = false

local CATEGORIES = {}
local HISTORY = {}
local STATUS = {}
local AD = {}

local selectedOffer = {}

local function sendAction(action, data)
  local protocolGame = g_game.getProtocolGame()
  if data == nil then
    data = {}
  end
  if protocolGame then
    protocolGame:sendExtendedOpcode(SHOP_EXTENTED_OPCODE, json.encode({action = action, data = data}))
  end  
end

-- public functions
function init()
  connect(g_game, {  onGameStart = check, onGameEnd = hide  })

  ProtocolGame.registerExtendedOpcode(SHOP_EXTENTED_OPCODE, onExtendedOpcode)

  if g_game.isOnline() then
    check()
  end
end

function terminate()
  disconnect(g_game, {  onGameStart = check, onGameEnd = hide  })

  ProtocolGame.unregisterExtendedOpcode(SHOP_EXTENTED_OPCODE, onExtendedOpcode)
  
  if shopButton then
    shopButton:destroy()
    shopButton = nil
  end
  if shop then
    disconnect(shop.categories, { onChildFocusChange = changeCategory })
    shop:destroy()
    shop = nil
  end
  if msgWindow then
    msgWindow:destroy()
  end
end

function check()
  if not g_game.getFeature(GameExtendedOpcode) then
    return
  end
  sendAction("init")
end

function hide()
  if not shop then
    return
  end
  shop:hide()
end

function show()
  if not shop or not shopButton then
    return
  end
  shop:show()
  shop:raise()
  shop:focus()
end

function toggle()
  if not shop then
    return
  end
  if shop:isVisible() then
    return hide()
  end
  show()
  check()
end

function onExtendedOpcode(protocol, code, buffer)
  if not shop then
    shop = g_ui.displayUI('shop')
    shop:hide()
    shopButton = modules.client_topmenu.addRightGameToggleButton('shopButton', tr('Shop'), '/images/topbuttons/shop', toggle)

    connect(shop.categories, { onChildFocusChange = changeCategory })
  end

  local json_status, json_data = pcall(function() return json.decode(buffer) end)
  if not json_status then
    g_logger.error("SHOP json error: " .. json_data)
    return false
  end

  local action = json_data['action']
  local data = json_data['data']
  local status = json_data['status']
  if not action or not data then
    return false
  end

  if action == 'categories' then
    processCategories(data)
  elseif action == 'history' then
    processHistory(data)
  elseif action == 'message' then
    processMessage(data)
  end

  if status then
    processStatus(status)
  end
end

function clearOffers()
  while shop.offers:getChildCount() > 0 do
    local child = shop.offers:getLastChild()
    shop.offers:destroyChildren(child)
  end
end

function clearCategories()
  CATEGORIES = {}
  clearOffers()
  while shop.categories:getChildCount() > 0 do
    local child = shop.categories:getLastChild()
    shop.categories:destroyChildren(child)
  end
end

function clearHistory()
  HISTORY = {}
  if browsingHistory then
    clearOffers()
  end
end

function processCategories(data)
  if table.equal(CATEGORIES,data) then
    return
  end
  clearCategories()
  CATEGORIES = data
  for i, category in ipairs(data) do
    addCategory(category)
  end
  if not browsingHistory then
    local firstCategory = shop.categories:getChildByIndex(1)
    if firstCategory then
      firstCategory:focus()
    end
  end
end

function processHistory(data)
  if table.equal(HISTORY,data) then
    return
  end
  HISTORY = data
  if browsingHistory then
    showHistory(true)
  end
end

function processMessage(data)
    if msgWindow then
      msgWindow:destroy()
    end
      
    local title = tr(data["title"])
    local msg = data["msg"]
    msgWindow = displayInfoBox(title, msg)
    msgWindow:show()
    msgWindow:raise()
    msgWindow:focus()
    msgWindow:raise()  
end

function processStatus(data)
  if table.equal(STATUS,data) then
    return
  end
  STATUS = data

  if data['ad'] then 
    processAd(data['ad'])
  end
  if data['points'] then
    shop.infoPanel.points:setText(tr("Points:") .. " " .. data['points'])
  end
  if data['buyUrl'] and data['buyUrl']:sub(1, 4):lower() == "http" then
    shop.infoPanel.buy:show()
    shop.infoPanel.buy.onMouseRelease = function() 
      scheduleEvent(function() g_platform.openUrl(data['buyUrl']) end, 50)
    end
  else
    shop.infoPanel.buy:hide()
  end
end

function processAd(data)
  if table.equal(AD,data) then
    return
  end
  AD = data
  
  if data['image'] and data['image']:sub(1, 4):lower() == "http" then
    HTTP.downloadImage(data['image'], function(path, err) 
      if err then g_logger.warning("HTTP error: " .. err) return end
      shop.adPanel:setHeight(shop.infoPanel:getHeight())
      shop.adPanel.ad:setText("")
      shop.adPanel.ad:setImageSource(path)
      shop.adPanel.ad:setImageFixedRatio(true)
      shop.adPanel.ad:setImageAutoResize(true)
      shop.adPanel.ad:setHeight(shop.infoPanel:getHeight())
    end)
  elseif data['text'] and data['text']:len() > 0 then
      shop.adPanel:setHeight(shop.infoPanel:getHeight())
      shop.adPanel.ad:setText(data['text'])
      shop.adPanel.ad:setHeight(shop.infoPanel:getHeight())
  else
      shop.adPanel:setHeight(0)
  end
  if data['url'] and data['url']:sub(1, 4):lower() == "http" then
    shop.adPanel.ad.onMouseRelease = function() 
      scheduleEvent(function() g_platform.openUrl(data['url']) end, 50)
    end
  else
    shop.adPanel.ad.onMouseRelease = nil
  end
end

function addCategory(data)
  local category
  if data["type"] == "item" then
    category = g_ui.createWidget('ShopCategoryItem', shop.categories)  
    category.item:setItemId(data["item"])
    category.item:setItemCount(data["count"])
    category.item:setShowCount(false)
  elseif data["type"] == "outfit" then
    category = g_ui.createWidget('ShopCategoryCreature', shop.categories)
    category.creature:setOutfit(data["outfit"])
    if data["outfit"]["rotating"] then
      category.creature:setAutoRotating(true)
    end
  elseif data["type"] == "image" then
    category = g_ui.createWidget('ShopCategoryImage', shop.categories)
    if data["image"]:sub(1, 4):lower() == "http" then
       HTTP.downloadImage(data['image'], function(path, err) 
        if err then g_logger.warning("HTTP error: " .. err) return end
        category.image:setImageSource(path)
      end)
    else
      category.image:setImageSource(data["image"])
    end
  else
    g_logger.error("Invalid shop category type: " .. tostring(data["type"]))
    return
  end
  category:setId("category_" .. shop.categories:getChildCount())
  category.name:setText(data["name"])
end

function showHistory(force)
  if browsingHistory and not force then
    return
  end
  sendAction("history")
  browsingHistory = true
  clearOffers()
  shop.categories:focusChild(nil)
  for i, transaction in ipairs(HISTORY) do
    addOffer(0, transaction)
  end
end

function addOffer(category, data)
  local offer
  if data["type"] == "item" then
    offer = g_ui.createWidget('ShopOfferItem', shop.offers)  
    offer.item:setItemId(data["item"])
    offer.item:setItemCount(data["count"])
    offer.item:setShowCount(false)
  elseif data["type"] == "outfit" then
    offer = g_ui.createWidget('ShopOfferCreature', shop.offers)
    offer.creature:setOutfit(data["outfit"])
    if data["outfit"]["rotating"] then
      offer.creature:setAutoRotating(true)
    end
  elseif data["type"] == "image" then
    offer = g_ui.createWidget('ShopOfferImage', shop.offers)
    if data["image"]:sub(1, 4):lower() == "http" then
      HTTP.downloadImage(data['image'], function(path, err) 
        if err then g_logger.warning("HTTP error: " .. err) return end
        offer.image:setImageSource(path)
      end)
    elseif data["image"] and data["image"]:len() > 1 then
      offer.image:setImageSource(data["image"])
    end
  else
    g_logger.error("Invalid shop offer type: " .. tostring(data["type"]))
    return
  end
  offer:setId("offer_" .. category .. "_" .. shop.offers:getChildCount())
  offer.title:setText(data["title"] .. " (" .. data["cost"] .. " points)")
  offer.description:setText(data["description"])  
  if category ~= 0 then
    offer.onDoubleClick = buyOffer
  end
end


function changeCategory(widget, newCategory)
  if not newCategory then
    return
  end
  browsingHistory = false
  local id = tonumber(newCategory:getId():split("_")[2])
  clearOffers()
  for i, offer in ipairs(CATEGORIES[id]["offers"]) do
    addOffer(id, offer)
  end
end

function buyOffer(widget)
  if not widget then
    return
  end
  local split = widget:getId():split("_")
  if #split ~= 3 then
    return
  end
  local category = tonumber(split[2])  
  local offer = tonumber(split[3])  
  local item = CATEGORIES[category]["offers"][offer]
  if not item then
    return
  end
  
  selectedOffer = {category=category, offer=offer, title=item.title, cost=item.cost}
  
  scheduleEvent(function()
      if msgWindow then
        msgWindow:destroy()
      end
      
      local title = tr("Buying from shop")
      local msg = "Do you want to buy " ..  item.title .. " for " .. item.cost .. " premium points?"
      msgWindow = displayGeneralBox(title, msg, {
          { text=tr('Yes'), callback=buyConfirmed },
          { text=tr('No'), callback=buyCanceled },
          anchor=AnchorHorizontalCenter}, buyConfirmed, buyCanceled)
      msgWindow:show()
      msgWindow:raise()
      msgWindow:focus()
      msgWindow:raise()
    end, 50)
end

function buyConfirmed()
  msgWindow:destroy()
  msgWindow = nil
  sendAction("buy", selectedOffer)
end

function buyCanceled()
  msgWindow:destroy()
  msgWindow = nil
  selectedOffer = {}
end