local addonName, addon = ...
local ui = addon:GetModule("Options.UI")
local options = addon:NewModule("Options.Menu")
local L = LibStub("AceLocale-3.0"):GetLocale(addonName)

local function menuItems()
	local index = 0
	return function ()
		index = index + 1
		for name, order in pairs(addon.db.profile.menu) do
			if order == index then
				return name
			end
		end
	end
end

local function updateMenuDb(visibleItems)
	local menu = {}
	for i, item in visibleItems:Items() do
		local interface = addon.display:GetInterface(item:GetText())
		menu[interface.name] = i
	end
	-- Sets items that are not visible with zero so when the list of visible items is empty
	--	AceDB won't change back to the default profile and everything will reset.
	for _, interface in addon.display:Interfaces() do
		local exists = menu[interface.name]
		if not exists then
			menu[interface.name] = 0
		end
	end
	addon.db.profile.menu = menu
	addon:UpdateMenu()
end

local function addAvailableItems(availableItems)
	for _, interface in addon.display:Interfaces() do
		local order = addon.db.profile.menu[interface.name]
		if order == 0 then
			local item = ui:CreateListItem()
			item:SetText(interface.title)
			availableItems:AddItem(item)
		end
	end
end

local function addVisibleItems(visibleItems)
	for name in menuItems() do
		local interface = addon.display:GetInterface(name)
		if interface and interface.title then
			local item = ui:CreateListItem()
			item:SetText(interface.title)
			visibleItems:AddItem(item)
		end
	end
end

local function reset(availableItems, visibleItems)
	visibleItems:Clear()
	addVisibleItems(visibleItems)
	updateMenuDb(visibleItems)

	availableItems:Clear()
	addAvailableItems(availableItems)

	addon:UpdateMenu()
end

function options:OnInitialize()
	local order = addon.options:AddSubCategory(L["Menu"])

	local availableItems = ui:CreateList(order)
	availableItems:SetTitle("Available Interfaces")
	availableItems:SetPoint("TOPLEFT", 10, -80)
	availableItems:SetSize(220, 435)

	local visibleItems = ui:CreateList(order)
	visibleItems:SetTitle("Visible Menu Items")
	visibleItems:SetPoint("TOPLEFT", availableItems, "TOPRIGHT", 23, 0)
	visibleItems:SetSize(220, 435)

	reset(availableItems, visibleItems)

	local addToButton = ui:CreateButton(availableItems)
	addToButton:SetSize(24, 24)
	addToButton:SetPoint("CENTER", availableItems, "RIGHT", 12, 0)
	addToButton:SetNormalTexture([[Interface\Buttons\UI-SpellbookIcon-NextPage-Up]])
	addToButton:SetPushedTexture([[Interface\Buttons\UI-SpellbookIcon-NextPage-Down]])
	addToButton:OnClick(function()
		availableItems:MoveSelectedTo(visibleItems)
		updateMenuDb(visibleItems)
	end)

	local removeFromButton = ui:CreateButton(availableItems)
	removeFromButton:SetSize(24, 24)
	removeFromButton:SetPoint("TOP", addToButton, "BOTTOM")
	removeFromButton:SetNormalTexture([[Interface\Buttons\UI-SpellbookIcon-PrevPage-Up]])
	removeFromButton:SetPushedTexture([[Interface\Buttons\UI-SpellbookIcon-PrevPage-Down]])
	removeFromButton:OnClick(function()
		visibleItems:MoveSelectedTo(availableItems)
		updateMenuDb(visibleItems)
	end)

	local moveUpButton = ui:CreateButton(visibleItems)
	moveUpButton:SetSize(24, 24)
	moveUpButton:SetPoint("TOPLEFT", visibleItems, "TOPRIGHT", 0, 5)
	moveUpButton:SetNormalTexture([[Interface\ChatFrame\UI-ChatIcon-ScrollUp-Up]])
	moveUpButton:SetPushedTexture([[Interface\ChatFrame\UI-ChatIcon-ScrollUp-Down]])
	moveUpButton:OnClick(function()
		visibleItems:MoveSelectedUp()
		updateMenuDb(visibleItems)
	end)

	local moveDownButton = ui:CreateButton(visibleItems)
	moveDownButton:SetSize(24, 24)
	moveDownButton:SetPoint("TOP", moveUpButton, "BOTTOM")
	moveDownButton:SetNormalTexture([[Interface\ChatFrame\UI-ChatIcon-ScrollDown-Up]])
	moveDownButton:SetPushedTexture([[Interface\ChatFrame\UI-ChatIcon-ScrollDown-Down]])
	moveDownButton:OnClick(function()
		visibleItems:MoveSelectedDown()
		updateMenuDb(visibleItems)
	end)
end