local MER, E, L, V, P, G = unpack(select(2, ...))
local MERS = MER:GetModule('MER_Skins')
local S = E:GetModule('Skins')

--Cache global variables
--Lua Variables
local _G = _G
local tostring, unpack = tostring, unpack
local strtrim = strtrim
local math_max, math_ceil = math.max, math.ceil
local tinsert = table.insert
--WoW API / Variables
local C_Heirloom_IsItemHeirloom = C_Heirloom.IsItemHeirloom
local C_Heirloom_PlayerHasHeirloom = C_Heirloom.PlayerHasHeirloom
local CanAffordMerchantItem = CanAffordMerchantItem
local CreateFrame = CreateFrame
local GetBuybackItemLink = GetBuybackItemLink
local GetCurrencyInfo = GetCurrencyInfo
local GetItemClassInfo = GetItemClassInfo
local GetItemInfo = GetItemInfo
local GetItemQualityColor = GetItemQualityColor
local GetMerchantItemInfo = GetMerchantItemInfo
local GetMerchantItemID = GetMerchantItemID
local GetMerchantItemLink = GetMerchantItemLink
local GetMerchantNumItems = GetMerchantNumItems
local hooksecurefunc = hooksecurefunc
local UIParent = UIParent
local SetItemButtonCount = SetItemButtonCount
local SetItemButtonStock = SetItemButtonStock
local SetItemButtonTexture = SetItemButtonTexture
local MerchantFrame_UpdateAltCurrency = MerchantFrame_UpdateAltCurrency
local MoneyFrame_SetMaxDisplayWidth = MoneyFrame_SetMaxDisplayWidth
local MoneyFrame_Update = MoneyFrame_Update
local MerchantFrameItem_UpdateQuality = MerchantFrameItem_UpdateQuality
local SetMoneyFrameColor = SetMoneyFrameColor
local SetItemButtonNameFrameVertexColor = SetItemButtonNameFrameVertexColor
local SetItemButtonSlotVertexColor = SetItemButtonSlotVertexColor
local SetItemButtonTextureVertexColor = SetItemButtonTextureVertexColor
local SetItemButtonNormalTextureVertexColor = SetItemButtonNormalTextureVertexColor
-- GLOBALS:

local ItemsPerSubpage, SubpagesPerPage
local RETRIEVING_ITEM_INFO, RETRIEVING_ITEM_INFO, MISCELLANEOUS, MOUNT, ITEM_SPELL_KNOWN, SEARCH = RETRIEVING_ITEM_INFO, RETRIEVING_ITEM_INFO, MISCELLANEOUS, MOUNT, ITEM_SPELL_KNOWN, SEARCH
local MAX_MONEY_DISPLAY_WIDTH = 120
local RECIPE = GetItemClassInfo(_G.LE_ITEM_CLASS_RECIPE)
local searchBox
local searching = ""

local function SkinVendorItems(i)
	local button = _G["MerchantItem"..i]
	local bu = _G["MerchantItem"..i.."ItemButton"]
	local mo = _G["MerchantItem"..i.."MoneyFrame"]
	local ic = bu.icon
	local IconBorder = bu.IconBorder

	bu:SetHighlightTexture("")
	bu:CreateBackdrop()
	bu:StyleButton(false)

	_G["MerchantItem"..i.."SlotTexture"]:Hide()
	_G["MerchantItem"..i.."NameFrame"]:Hide()

	local a1, p, a2 = bu:GetPoint()
	bu:SetPoint(a1, p, a2, -1, -1)
	bu:SetNormalTexture("")
	bu:SetPushedTexture("")

	local a3, p2, a4, x, y = mo:GetPoint()
	mo:SetPoint(a3, p2, a4, x, y+2)

	MERS:CreateBD(bu, 0)

	button.bd = CreateFrame("Frame", nil, button, "BackdropTemplate")
	button.bd:SetPoint("TOPLEFT", 39, 0)
	button.bd:SetPoint("BOTTOMRIGHT")
	button.bd:SetFrameLevel(0)
	MERS:CreateBD(button.bd, .25)
	MERS:CreateGradient(button.bd)

	ic:SetTexCoord(unpack(E.TexCoords))
	ic:ClearAllPoints()
	ic:Point('TOPLEFT', 1, -1)
	ic:Point('BOTTOMRIGHT', -1, 1)
	IconBorder:SetAlpha(0)

	-- Hide ElvUI's backdrop
	if button.backdrop then
		button.backdrop:Hide()
	end

	_G.MerchantBuyBackItemItemButton.IconBorder:SetAlpha(0)

	hooksecurefunc(IconBorder, 'SetVertexColor', function(self, r, g, b)
		bu.backdrop:SetBackdropBorderColor(r, g, b)
	end)

	hooksecurefunc(IconBorder, 'Hide', function(self)
		bu.backdrop:SetBackdropBorderColor(unpack(E.media.bordercolor))
	end)

	MER.NPC:Register(_G.MerchantFrame)
end

local function UpdateButtonsPositions(isBuyBack)
	local btn
	local vertSpacing, horizSpacing

	if (isBuyBack) then
		vertSpacing = -30
		horizSpacing = 50
		searchBox:Hide()
	else
		vertSpacing = -16
		horizSpacing = 12
		searchBox:Show()
	end

	for i = 1, _G.MERCHANT_ITEMS_PER_PAGE do
		btn = _G["MerchantItem" .. i]
		if (isBuyBack) then
			if (i > _G.BUYBACK_ITEMS_PER_PAGE) then
				btn:Hide()
			else
				if (i == 1) then
					btn:SetPoint("TOPLEFT", _G["MerchantFrame"], "TOPLEFT", 64, -105)
				else
					if ((i % 3) == 1) then
						btn:SetPoint("TOPLEFT", _G["MerchantItem" .. (i-3)], "BOTTOMLEFT", 0, vertSpacing)
					else
						btn:SetPoint("TOPLEFT", _G["MerchantItem" .. (i-1)], "TOPRIGHT", horizSpacing, 0)
					end
				end
			end
		else
			btn:Show()
			if ((i % ItemsPerSubpage) == 1) then
				if (i == 1) then
					btn:SetPoint("TOPLEFT", _G["MerchantFrame"], "TOPLEFT", 24, -70)
				else
					btn:SetPoint("TOPLEFT", _G["MerchantItem" .. (i-(ItemsPerSubpage - 1))], "TOPRIGHT", 12, 0)
				end
			else
				if ((i % 2) == 1) then
					btn:SetPoint("TOPLEFT", _G["MerchantItem" .. (i-2)], "BOTTOMLEFT", 0, vertSpacing)
				else
					btn:SetPoint("TOPLEFT", _G["MerchantItem" .. (i-1)], "TOPRIGHT", horizSpacing, 0)
				end
			end
		end
	end
end

local function UpdateBuybackInfo()
	UpdateButtonsPositions(true)

	-- apply coloring
	local btn, link, quality, r, g, b, _
	for i = 1, _G.BUYBACK_ITEMS_PER_PAGE, 1 do
		btn = _G["MerchantItem" .. i]
		if (btn) then
			link = GetBuybackItemLink(i)
			if (link) then
				_, _, quality = GetItemInfo(link)
				if quality then
					r, g, b = GetItemQualityColor(quality)
				else
					r, g, b = 1, 1, 1
				end
				_G["MerchantItem" .. i .. "Name"]:SetTextColor(r, g, b)
			end
		end
	end
end

local function isKnown(link, itemType, itemSubType)
	if ( not link ) then
		return false
	end

	local upperLimit
	local isMount = false
	local isRecipe = false
	if itemType == RECIPE then
		isRecipe = true
	elseif itemType == MISCELLANEOUS and itemSubType == MOUNT then
		isMount = true
	end

	_G["MER_Merchant_HiddenTooltip"]:SetOwner(UIParent, "ANCHOR_NONE")
	_G["MER_Merchant_HiddenTooltip"]:SetHyperlink(link)
	upperLimit = isRecipe and _G["MER_Merchant_HiddenTooltip"]:NumLines() or 0

	for i = 2, _G["MER_Merchant_HiddenTooltip"]:NumLines() do
		if (isRecipe and (i <= 5 or i >= upperLimit - 3)) or isMount or not isRecipe then
			local text = _G["MER_Merchant_HiddenTooltipTextLeft"..i]
			local r, g, b = text:GetTextColor()
			local gettext = text:GetText()

			if ( gettext and r >= 0.9 and g <= 0.2 and b <= 0.2 and gettext ~= RETRIEVING_ITEM_INFO ) then
				if gettext == ITEM_SPELL_KNOWN then return true end
			end
		end
	end

	return false
end

local function UpdateMerchantInfo()
	UpdateButtonsPositions()

	local totalMerchantItems = GetMerchantNumItems()
	local visibleMerchantItems = 0
	local indexes = {}
	local _, name, texture, price, quantity, numAvailable, isPurchasable, isUsable, extendedCost, r, g, b, notOptimal
	local link, quality, itemLevel, itemMinLevel, itemType, itemSubType, itemStackCount, itemEquipLoc, itemSellPrice, itemId

	for i = 1, totalMerchantItems do
		tinsert(indexes, i)
		visibleMerchantItems = visibleMerchantItems + 1
	end

	 -- validate current page shown
	if (_G["MerchantFrame"].page > math_max(1, math_ceil(visibleMerchantItems / _G.MERCHANT_ITEMS_PER_PAGE))) then
		_G["MerchantFrame"].page = math_max(1, math_ceil(visibleMerchantItems / _G.MERCHANT_ITEMS_PER_PAGE))
	end

	-- Show correct page count based on number of items shown
	_G["MerchantPageText"]:SetFormattedText(_G.MERCHANT_PAGE_NUMBER, _G["MerchantFrame"].page, math_ceil(visibleMerchantItems / _G.MERCHANT_ITEMS_PER_PAGE))

	for i = 1, _G.MERCHANT_ITEMS_PER_PAGE do
		local index = ((_G["MerchantFrame"].page - 1) * _G.MERCHANT_ITEMS_PER_PAGE) + i
		local itemButton = _G["MerchantItem" .. i .. "ItemButton"]
		itemButton.link = nil
		local merchantButton = _G["MerchantItem" .. i]
		local merchantMoney = _G["MerchantItem" .. i .. "MoneyFrame"]
		local merchantAltCurrency = _G["MerchantItem" .. i .. "AltCurrencyFrame"]

		if (index <= visibleMerchantItems) then
			-- ItemLevel
			if itemButton and itemButton:IsShown() then
				if not itemButton.text then
					itemButton.text = MER:CreateText(itemButton, "OVERLAY", 10)
					itemButton.text:ClearAllPoints()
					itemButton.text:Point("BOTTOMRIGHT", 2, -9)
				else
					itemButton.text:SetText("")
				end

				-- ItemLevel on MerchantFrame
				local itemLink = GetMerchantItemLink(index)
				if itemLink then
					local _, _, quality, itemlevel, _, _, _, _, _, _, _, itemClassID = GetItemInfo(itemLink)
					local color = _G.BAG_ITEM_QUALITY_COLORS[quality or 1]
					if (itemlevel and itemlevel > 1) and (quality and quality > 1) and (itemClassID == _G.LE_ITEM_CLASS_WEAPON or itemClassID == _G.LE_ITEM_CLASS_ARMOR) then
						itemButton.text:SetText(itemlevel)
						itemButton.text:SetTextColor(color.r, color.g, color.b)
					end
				end
			end

			name, texture, price, quantity, numAvailable, isPurchasable, isUsable, extendedCost = GetMerchantItemInfo(indexes[index])
			if (name ~= nil) then
				local canAfford = CanAffordMerchantItem(index)
				_G["MerchantItem"..i.."Name"]:SetText(name)
				SetItemButtonCount(itemButton, quantity)
				SetItemButtonStock(itemButton, numAvailable)
				SetItemButtonTexture(itemButton, texture)

				if ( extendedCost and (price <= 0) ) then -- update item's currency info
					itemButton.price = nil
					itemButton.extendedCost = true
					itemButton.name = name
					itemButton.link = GetMerchantItemLink(indexes[index])
					itemButton.texture = texture
					MerchantFrame_UpdateAltCurrency(index, i, canAfford)
					merchantAltCurrency:ClearAllPoints()
					merchantAltCurrency:Point("BOTTOMLEFT", "MerchantItem"..i.."NameFrame", "BOTTOMLEFT", 0, 31)
					merchantMoney:Hide()
					merchantAltCurrency:Show()
				elseif ( extendedCost and (price > 0) ) then
					itemButton.price = price
					itemButton.extendedCost = true
					itemButton.name = name
					itemButton.link = GetMerchantItemLink(indexes[index])
					itemButton.texture = texture
					local altCurrencyWidth = MerchantFrame_UpdateAltCurrency(index, i, canAfford)
					MoneyFrame_SetMaxDisplayWidth(merchantMoney, MAX_MONEY_DISPLAY_WIDTH - altCurrencyWidth)
					MoneyFrame_Update(merchantMoney:GetName(), price)
					local color
					if (canAfford == false) then
						color = "red"
					end
					SetMoneyFrameColor(merchantMoney:GetName(), color)
					merchantAltCurrency:ClearAllPoints()
					merchantAltCurrency:Point("LEFT", merchantMoney:GetName(), "RIGHT", -14, 0)
					merchantAltCurrency:Show()
					merchantMoney:Show()
				else
					itemButton.price = price
					itemButton.extendedCost = nil
					itemButton.name = name
					itemButton.link = GetMerchantItemLink(indexes[index])
					itemButton.texture = texture
					MoneyFrame_SetMaxDisplayWidth(merchantMoney, MAX_MONEY_DISPLAY_WIDTH)
					MoneyFrame_Update(merchantMoney:GetName(), price)
					local color
					if (canAfford == false) then
						color = "red"
					end
					SetMoneyFrameColor(merchantMoney:GetName(), color)
					merchantAltCurrency:Hide()
					merchantMoney:Show()
				end

				MerchantFrameItem_UpdateQuality(merchantButton, itemButton.link)

				local merchantItemID = GetMerchantItemID(index)
				local isHeirloom = merchantItemID and C_Heirloom_IsItemHeirloom(merchantItemID)
				local isKnownHeirloom = isHeirloom and C_Heirloom_PlayerHasHeirloom(merchantItemID)

				itemButton.showNonrefundablePrompt = isHeirloom

				itemButton.hasItem = true
				itemButton:SetID(indexes[index])
				itemButton:Show()

				local tintRed = not isPurchasable or (not isUsable and not isHeirloom)

				local colorMult = 1.0
				local detailColor = {}
				local slotColor = {}
				-- unavailable items (limited stock, bought out) are darkened
				if ( numAvailable == 0 or isKnownHeirloom) then
					colorMult = 0.5
				end
				if ( tintRed ) then
					slotColor = {r = 1.0, g = 0, b = 0}
					detailColor = {r = 1.0, g = 0, b = 0}
				else
					if not isKnown(itemButton.link, itemType, itemSubType) then
						slotColor = {r = 1.0, g = 1.0, b = 1.0}
						detailColor = {r = 0.5, g = 0.5, b = 0.5}
					else
						slotColor = {r = 1.0, g = 0, b = 0}
						detailColor = {r = 1.0, g = 0, b = 0}
					end
				end
				local alpha = 0.3
				if ( searching == "" or searching == SEARCH:lower() or name:lower():match(searching)
					or ( quality and ( tostring(quality):lower():match(searching) or _G["ITEM_QUALITY"..tostring(quality).."_DESC"]:lower():match(searching) ) )
					or ( itemType and itemType:lower():match(searching) )
					or ( itemSubType and itemSubType:lower():match(searching) )
					) then
					alpha = 1
				end

				merchantButton:SetAlpha(alpha)

				SetItemButtonNameFrameVertexColor(merchantButton, detailColor.r * colorMult, detailColor.g * colorMult, detailColor.b * colorMult)
				SetItemButtonSlotVertexColor(merchantButton, slotColor.r * colorMult, slotColor.g * colorMult, slotColor.b * colorMult)
				SetItemButtonTextureVertexColor(itemButton, slotColor.r * colorMult, slotColor.g * colorMult, slotColor.b * colorMult)
				SetItemButtonNormalTextureVertexColor(itemButton, slotColor.r * colorMult, slotColor.g * colorMult, slotColor.b * colorMult)
			end
		else
			itemButton.price = nil
			itemButton.hasItem = nil
			itemButton.name = nil
			itemButton:Hide()
			SetItemButtonNameFrameVertexColor(merchantButton, 0.5, 0.5, 0.5)
			SetItemButtonSlotVertexColor(merchantButton,0.4, 0.4, 0.4)
			_G["MerchantItem"..i.."Name"]:SetText("")
			_G["MerchantItem"..i.."MoneyFrame"]:Hide()
			_G["MerchantItem"..i.."AltCurrencyFrame"]:Hide()
		end
	end
end

local function RebuildMerchantFrame()
	ItemsPerSubpage = _G.MERCHANT_ITEMS_PER_PAGE
	SubpagesPerPage = E.db.mui.merchant.subpages
	_G.MERCHANT_ITEMS_PER_PAGE = SubpagesPerPage * 10 --Haven't seen this causing any taints so I asume it's ok
	_G["MerchantFrame"]:Width(42 + (318 * SubpagesPerPage) + (12 * (SubpagesPerPage - 1)))

	_G.MerchantFrame:Styling()
	MER:CreateBackdropShadow(_G.MerchantFrame)

	for i = 1, _G.MERCHANT_ITEMS_PER_PAGE do
		if (not _G["MerchantItem" .. i]) then
			CreateFrame("Frame", "MerchantItem" .. i, _G["MerchantFrame"], "MerchantItemTemplate")
			SkinVendorItems(i)
		end
	end

	for i = 1, _G.BUYBACK_ITEMS_PER_PAGE do
		local button = _G["MerchantItem"..i]
		-- Hide ElvUI's backdrop
		if button.backdrop then
			button.backdrop:SetTemplate("Transparent")
		end
	end

	 -- alter the position of the buyback item slot on the merchant tab
	_G["MerchantBuyBackItem"]:ClearAllPoints()
	_G["MerchantBuyBackItem"]:Point("TOPLEFT", _G["MerchantItem10"], "BOTTOMLEFT", -14, -20)

	-- move the next/previous page buttons
	_G["MerchantPrevPageButton"]:ClearAllPoints()
	_G["MerchantPrevPageButton"]:Point("CENTER", _G["MerchantFrame"], "BOTTOM", 50, 70)
	_G["MerchantPageText"]:ClearAllPoints()
	_G["MerchantPageText"]:Point("BOTTOM", _G["MerchantFrame"], "BOTTOM", 160, 65)
	_G["MerchantNextPageButton"]:ClearAllPoints()
	_G["MerchantNextPageButton"]:Point("CENTER", _G["MerchantFrame"], "BOTTOM", 270, 70)

	-- currency insets
	_G["MerchantExtraCurrencyInset"]:ClearAllPoints()
	_G["MerchantExtraCurrencyInset"]:Point("BOTTOMRIGHT", _G["MerchantMoneyInset"], "BOTTOMLEFT", 0, 0)
	_G["MerchantExtraCurrencyInset"]:Point("TOPLEFT", _G["MerchantMoneyInset"], "TOPLEFT", -165, 0)
	_G["MerchantExtraCurrencyBg"]:ClearAllPoints()
	_G["MerchantExtraCurrencyBg"]:Point("TOPLEFT", _G["MerchantExtraCurrencyInset"], "TOPLEFT", 3, -2)
	_G["MerchantExtraCurrencyBg"]:Point("BOTTOMRIGHT", _G["MerchantExtraCurrencyInset"], "BOTTOMRIGHT", -3, 2)

	searchBox = CreateFrame("EditBox", "$parentSearchBox", _G["MerchantFrame"], "InputBoxTemplate")
	searchBox:Width(_G["MerchantItem1"]:GetWidth())
	searchBox:Height(21)
	searchBox:ClearAllPoints()
	searchBox:Point("RIGHT", _G["MerchantFrameLootFilter"], "LEFT", 0, 2)
	searchBox:SetAutoFocus(false)
	searchBox:SetFontObject(_G.ChatFontSmall)
	searchBox:SetScript("OnTextChanged", function(self) searching = self:GetText():trim():lower() UpdateMerchantInfo() end)
	searchBox:SetScript("OnShow", function(self) self:SetText(SEARCH) searching = "" end)
	searchBox:SetScript("OnEnterPressed", function(self) self:ClearFocus() end)
	searchBox:SetScript("OnEscapePressed", function(self) self:ClearFocus() self:SetText(SEARCH) searching = "" end)
	searchBox:SetScript("OnEditFocusLost", function(self)
		self:HighlightText(0, 0)
		if (strtrim(self:GetText()) == "") then
			self:SetText(SEARCH)
			searching = ""
		end
	end)
	searchBox:SetScript("OnEditFocusGained", function(self)
		self:HighlightText()
		if (self:GetText():trim():lower() == SEARCH:lower()) then
			self:SetText("")
		end
	end)
	searchBox:SetText(SEARCH)
	S:HandleEditBox(searchBox)
end

local function MerchantSkinInit()
	if E.private.skins.blizzard.enable ~= true or E.private.skins.blizzard.merchant ~= true or E.db.mui.merchant.enable ~= true or not E.Retail then return end

	hooksecurefunc("MerchantFrame_UpdateBuybackInfo", UpdateBuybackInfo)

	RebuildMerchantFrame()
	UpdateButtonsPositions()
	CreateFrame("GameTooltip", "MER_Merchant_HiddenTooltip", UIParent, "GameTooltipTemplate")

	hooksecurefunc("MerchantFrame_UpdateMerchantInfo", UpdateMerchantInfo)
end

hooksecurefunc(S, "Initialize", MerchantSkinInit)
