local E, L, V, P, G = unpack(ElvUI)
local DT = E:GetModule("DataTexts")

local type, pairs, select, next = type, pairs, select, next
local sort, wipe = table.sort, wipe
local format, find, join, gsub = string.format, string.find, string.join, string.gsub

local UnitIsAFK = UnitIsAFK
local UnitIsDND = UnitIsDND
local SendChatMessage = SendChatMessage
local InviteUnit = InviteUnit
local SetItemRef = SetItemRef
local GetFriendInfo = GetFriendInfo
local GetNumFriends = GetNumFriends
local GetQuestDifficultyColor = GetQuestDifficultyColor
local UnitInParty = UnitInParty
local UnitInRaid = UnitInRaid
local ToggleFriendsFrame = ToggleFriendsFrame
local EasyMenu = EasyMenu
local AFK, DND = AFK, DND
local OPTIONS_MENU, OPTIONS_MENU, PLAYER_STATUS, PARTY_INVITE = OPTIONS_MENU, OPTIONS_MENU, PLAYER_STATUS, PARTY_INVITE
local CHAT_MSG_WHISPER_INFORM = CHAT_MSG_WHISPER_INFORM
local LOCALIZED_CLASS_NAMES_MALE = LOCALIZED_CLASS_NAMES_MALE
local LOCALIZED_CLASS_NAMES_FEMALE = LOCALIZED_CLASS_NAMES_FEMALE
local RAID_CLASS_COLORS = RAID_CLASS_COLORS

local menuFrame = CreateFrame("Frame", "FriendDatatextRightClickMenu", E.UIParent, "UIDropDownMenuTemplate")
local menuList = {
	{text = OPTIONS_MENU, isTitle = true, notCheckable = true},
	{text = PARTY_INVITE, hasArrow = true, notCheckable = true},
	{text = CHAT_MSG_WHISPER_INFORM, hasArrow = true, notCheckable= true},
	{text = PLAYER_STATUS, hasArrow = true, notCheckable = true,
		menuList = {
			{text = "|cff2BC226"..AVAILABLE.."|r", notCheckable = true, func = function() if UnitIsAFK("player") then SendChatMessage("", "AFK") elseif UnitIsDND("player") then SendChatMessage("", "DND") end end},
			{text = "|cffE7E716"..AFK.."|r", notCheckable = true, func = function() if not UnitIsAFK("player") then SendChatMessage("", "AFK") end end},
			{text = "|cffFF0000"..DND.."|r", notCheckable = true, func = function() if not UnitIsDND("player") then SendChatMessage("", "DND") end end}
		}
	}
}

local function GetNumberFriends()
	local numFriends = GetNumFriends()
	local onlineFriends = 0
	local _, online

	for i = 1, numFriends do
		_, _, _, _, online = GetFriendInfo(i)

		if online then
			onlineFriends = onlineFriends + 1
		end
	end

	return numFriends, onlineFriends
end

local function inviteClick(name)
	menuFrame:Hide()

	if type(name) ~= "number" then
		InviteUnit(name)
	end
end

local function whisperClick(name)
	menuFrame:Hide()

	SetItemRef("player:"..name, format("|Hplayer:%1$s|h[%1$s]|h", name), "LeftButton")
end

local levelNameString = "|cff%02x%02x%02x%d|r |cff%02x%02x%02x%s|r"
local levelNameClassString = "|cff%02x%02x%02x%d|r %s%s%s"
local totalOnlineString = join("", GUILD_ONLINE_LABEL, ": %s/%s")
local tthead = {r = 0.4, g = 0.78, b = 1}
local activezone, inactivezone = {r = 0.3, g = 1.0, b = 0.3}, {r = 0.65, g = 0.65, b = 0.65}
local displayString = ""
local statusTable = {" |cffFFFFFF[|r|cffFF9900"..L["AFK"].."|r|cffFFFFFF]|r", " |cffFFFFFF[|r|cffFF3333"..L["DND"].."|r|cffFFFFFF]|r", ""}
local groupedTable = {"|cffaaaaaa*|r", ""}
local friendTable = {}
local friendOnline, friendOffline = gsub(ERR_FRIEND_ONLINE_SS, "\124Hplayer:%%s\124h%[%%s%]\124h", ""), gsub(ERR_FRIEND_OFFLINE_S, "%%s", "")
local dataValid = false
local lastPanel

local function SortAlphabeticName(a, b)
	if a[1] and b[1] then
		return a[1] < b[1]
	end
end

local function BuildFriendTable(total)
	wipe(friendTable)
	local name, level, class, area, connected, status, note
	for i = 1, total do
		name, level, class, area, connected, status, note = GetFriendInfo(i)

		if status == "<"..AFK..">" then
			status = statusTable[1]
		elseif status == "<"..DND..">" then
			status = statusTable[2]
		else
			status = statusTable[3]
		end

		if connected then
			--other non-english locales require this
			for k, v in pairs(LOCALIZED_CLASS_NAMES_MALE) do if class == v then class = k end end
			for k, v in pairs(LOCALIZED_CLASS_NAMES_FEMALE) do if class == v then class = k end end

			friendTable[i] = {name, level, class, area, connected, status, note}
		end
	end
	if next(friendTable) then
		sort(friendTable, SortAlphabeticName)
	end
end

local function OnEvent(self, event, ...)
	local _, onlineFriends = GetNumberFriends()

	-- special handler to detect friend coming online or going offline
	-- when this is the case, we invalidate our buffered table and update the
	-- datatext information
	if event == "CHAT_MSG_SYSTEM" then
		local message = select(1, ...)
		if not (find(message, friendOnline) or find(message, friendOffline)) then return end
	end

	-- force update when showing tooltip
	dataValid = false

	self.text:SetFormattedText(displayString, FRIENDS, onlineFriends)

	lastPanel = self
end

local function OnClick(_, btn)
	DT.tooltip:Hide()

	if btn == "RightButton" then
		local menuCountWhispers = 0
		local menuCountInvites = 0
		local classc, levelc, info, shouldSkip

		menuList[2].menuList = {}
		menuList[3].menuList = {}

		if #friendTable > 0 then
			for i = 1, #friendTable do
				info = friendTable[i]
				if info[5] then
					shouldSkip = false
					if (info[6] == statusTable[1]) and E.db.datatexts.friends.hideAFK then
						shouldSkip = true
					elseif (info[6] == statusTable[2]) and E.db.datatexts.friends.hideDND then
						shouldSkip = true
					end
					if not shouldSkip then
						classc, levelc = (CUSTOM_CLASS_COLORS and CUSTOM_CLASS_COLORS[info[3]]) or RAID_CLASS_COLORS[info[3]], GetQuestDifficultyColor(info[2])
						classc = classc or GetQuestDifficultyColor(info[2])

						menuCountWhispers = menuCountWhispers + 1
						menuList[3].menuList[menuCountWhispers] = {text = format(levelNameString, levelc.r*255, levelc.g*255, levelc.b*255, info[2], classc.r*255, classc.g*255, classc.b*255, info[1]), arg1 = info[1], notCheckable = true, func = whisperClick}
						if not (UnitInParty(info[1]) or UnitInRaid(info[1])) then
							menuCountInvites = menuCountInvites + 1
							menuList[2].menuList[menuCountInvites] = {text = format(levelNameString, levelc.r*255, levelc.g*255, levelc.b*255, info[2], classc.r*255, classc.g*255, classc.b*255, info[1]), arg1 = info[1], notCheckable = true, func = inviteClick}
						end
					end
				end
			end
		end

		EasyMenu(menuList, menuFrame, "cursor", 0, 0, "MENU", 2)
	else
		ToggleFriendsFrame(1)
	end
end

local function OnEnter(self)
	DT:SetupTooltip(self)

	local numberOfFriends, onlineFriends = GetNumberFriends()

	-- no friends online, quick exit
	if onlineFriends == 0 then return end

	if not dataValid then
		-- only retrieve information for all on-line members when we actually view the tooltip
		if numberOfFriends > 0 then BuildFriendTable(numberOfFriends) end
		dataValid = true
	end

	local zonec, classc, levelc, info, grouped, shouldSkip
	DT.tooltip:AddDoubleLine(L["Friends List"], format(totalOnlineString, onlineFriends, numberOfFriends), tthead.r, tthead.g, tthead.b, tthead.r, tthead.g, tthead.b)
	if onlineFriends > 0 then
		for i = 1, #friendTable do
			info = friendTable[i]
			if info[5] then
				shouldSkip = false
				if (info[6] == statusTable[1]) and E.db.datatexts.friends.hideAFK then
					shouldSkip = true
				elseif (info[6] == statusTable[2]) and E.db.datatexts.friends.hideDND then
					shouldSkip = true
				end
				if not shouldSkip then
					if GetRealZoneText() == info[4] then zonec = activezone else zonec = inactivezone end
					classc, levelc = (CUSTOM_CLASS_COLORS and CUSTOM_CLASS_COLORS[info[3]]) or RAID_CLASS_COLORS[info[3]], GetQuestDifficultyColor(info[2])

					classc = classc or GetQuestDifficultyColor(info[2])

					if UnitInParty(info[1]) or UnitInRaid(info[1]) then grouped = 1 else grouped = 2 end
					DT.tooltip:AddDoubleLine(format(levelNameClassString, levelc.r*255, levelc.g*255, levelc.b*255, info[2], info[1], groupedTable[grouped], " " .. info[6]), info[4], classc.r, classc.g, classc.b, zonec.r, zonec.g, zonec.b)
				end
			end
		end
	end

	DT.tooltip:Show()
end

local function ValueColorUpdate(hex)
	displayString = join("", "%s: ", hex, "%d|r")

	if lastPanel ~= nil then
		OnEvent(lastPanel, "ELVUI_COLOR_UPDATE")
	end
end
E.valueColorUpdateFuncs[ValueColorUpdate] = true

DT:RegisterDatatext("Friends", {"PLAYER_LOGIN", "FRIENDLIST_UPDATE", "CHAT_MSG_SYSTEM"}, OnEvent, nil, OnClick, OnEnter, nil, FRIENDS)