-- ========================================================================= --
--                              SylingTracker                                --
--           https://www.curseforge.com/wow/addons/sylingtracker             --
--                                                                           --
--                               Repository:                                 --
--                   https://github.com/Skamer/SylingTracker                 --
--                                                                           --
-- ========================================================================= --
Syling                 "SylingTracker.UI.ListView"                           ""
-- ========================================================================= --
export {
  newtable                            = System.Toolset.newtable,
  IsObjectType                        = Class.IsObjectType,
}

__UIElement__()
class "ListView" (function(_ENV)
  inherit "Frame" extend "IView"
  -----------------------------------------------------------------------------
  --                               Methods                                   --
  -----------------------------------------------------------------------------
  function OnViewUpdate(self, data, metadata)
    wipe(self.ViewKeys)

    if data and self.ViewClass then 
      local previousView
      local paddingLeft = Style[self].PaddingLeft or 0
      local paddingTop = Style[self].PaddingTop or 0
      local paddingRight = Style[self].paddingRight or 0

      for key, itemData, itemMetadata in self:IterateData(data) do
        local classType = self:GetViewClass(itemData, metadata)

        if classType then 
          local view = self:AcquireView(key, classType)
          view:ClearAllPoints()

          if previousView then 
            view:SetPoint("TOP", previousView, "BOTTOM", 0, -self.Spacing)
          else
            local firstRegion = self:GetFirstRegion()
            if firstRegion == self then 
              view:SetPoint("TOP", 0, -paddingTop)
            else
              view:SetPoint("TOP", firstRegion, "BOTTOM", 0, -paddingTop)
            end
          end
          
          view:SetPoint("LEFT", paddingLeft, 0)
          view:SetPoint("RIGHT", -paddingRight, 0)

          -- Update the view with the data 
          view:UpdateView(itemData, itemMetadata)

          previousView = view

          self.ViewKeys[key] = true 
        end
      end
    end
    
    self:ReleaseUnusedViews()
  end

  function GetFirstRegion(self)
    return self
  end

  __Iterator__()
  function IterateData(self, data, metadata)
    local yield = coroutine.yield
    local iterator = self.Indexed and ipairs or pairs 

    for k, v in iterator(data) do 
      yield(k, v, metadata)
    end
  end

  function AcquireView(self, key, classType)
    local view = self.Views[key]
    local new = false 

    if view and not IsObjectType(view, classType) then 
      view.OnSizeChanged = view.OnSizeChanged - self.OnViewSizeChanged

      view:Release()
      self.Views[key] = nil 

      new = true
    end

    if not view or new then 
      view = classType.Acquire()
      view:SetParent(self)
      view:Show()

      view.OnSizeChanged = view.OnSizeChanged + self.OnViewSizeChanged

      self.Views[key] = view 

      new = true 
    end

    return view, new
  end

  function OnAdjustHeight(self)
    local height = 0
    local count = 0
    local paddingTop = Style[self].PaddingTop or 0
    local paddingBottom = Style[self].PaddingBottom or 0

    for childName, child in pairs(self.Views) do 
      height = height + child:GetHeight()

      count = count + 1
    end

    height = height + self.Spacing * math.max(0, count - 1) + paddingBottom + paddingTop

    self:SetHeight(height)
  end

  function GetViewClass(self, data, ...)
    if type(self.ViewClass) == "function" then 
      return self.ViewClass(data, ...)
    end

    return self.ViewClass
  end

  function ReleaseUnusedViews(self)
    for key, view in pairs(self.Views) do
      if not self.ViewKeys[key] then
        view.OnSizeChanged = view.OnSizeChanged - self.OnViewSizeChanged
        view:Release() 
        
        self.Views[key] = nil
      end
    end
  end
  -----------------------------------------------------------------------------
  --                               Properties                                --
  -----------------------------------------------------------------------------
  property "ViewClass" {
    type = ClassType + Function,
    handler = function(self) self:RefreshView() end
  }

  property "ViewKeys" {
    set = false,
    default = function() return {} end
  }

  property "Views" {
    set = false,
    default = function() return newtable(false, true) end 
  }

  property "Indexed" {
    type = Boolean,
    default = false 
  }

  property "Spacing" {
    type = Number,
    default = 10,
    handler = function(self) self:RefreshView() end
  }
  -----------------------------------------------------------------------------
  --                            Constructors                                 --
  -----------------------------------------------------------------------------
  __Template__ {}
  function __ctor(self)
    self:InstantApplyStyle()
    self:SetHeight(1)

    self.OnViewSizeChanged = function() self:AdjustHeight() end
  end
end)


class "ListViewWithHeaderText" (function(_ENV)
  inherit "ListView"

  function GetFirstRegion(self)
    return self:GetChild("HeaderText")
  end

  function OnAdjustHeight(self)
    local height = 0
    local count = 0
    local paddingTop = Style[self].PaddingTop or 0
    local paddingBottom = Style[self].PaddingBottom or 0

    height = self:GetChild("HeaderText"):GetHeight() + 5

    for childName, child in pairs(self.Views) do 
      height = height + child:GetHeight()

      count = count + 1
    end

    height = height + self.Spacing * math.max(0, count - 1) + paddingBottom + paddingTop

    self:SetHeight(height)
  end
  -----------------------------------------------------------------------------
  --                            Constructors                                 --
  -----------------------------------------------------------------------------
  __Template__ {
    HeaderText = FontString
  }
  function __ctor(self)
  end
end)
-------------------------------------------------------------------------------
--                                Styles                                     --
-------------------------------------------------------------------------------
Style.UpdateSkin("Default", {
  [ListView] = {
    autoAdjustHeight = true,
    paddingLeft = 5,
    paddingBottom = 5,
    paddingTop = 5,
    paddingRight = 5,
  },

  [ListViewWithHeaderText] = {
    HeaderText = {
      location = {
        Anchor("TOP", 0, -5),
        Anchor("LEFT"),
        Anchor("RIGHT")
      }
    }
  }
})