local LibChatBubble = CogWheel:Set("LibChatBubble", 2)
if (not LibChatBubble) then	
	return
end

-- We require this library to properly handle startup events
local LibClientBuild = CogWheel("LibClientBuild")
assert(LibClientBuild, "LibChatBubble requires LibClientBuild to be loaded.")

local LibEvent = CogWheel("LibEvent")
assert(LibEvent, "LibChatBubble requires LibEvent to be loaded.")

-- Embed event functionality into this
LibEvent:Embed(LibChatBubble)

-- Lua API
local _G = _G

local ipairs = ipairs
local math_abs = math.abs
local math_floor = math.floor
local pairs = pairs
local select = select
local tostring = tostring

-- WoW API
local Ambiguate = _G.Ambiguate
local CreateFrame = _G.CreateFrame
local IsInInstance = _G.IsInInstance
local SetCVar = _G.SetCVar
local WorldFrame = _G.WorldFrame
local C_ChatBubbles = _G.C_ChatBubbles
local GetAllChatBubbles = C_ChatBubbles and C_ChatBubbles.GetAllChatBubbles


-- Client Constants
local ENGINE_LEGION_720 = LibClientBuild:IsBuild("7.2.0")
local ENGINE_LEGION_725 = LibClientBuild:IsBuild("7.2.5")

-- Textures
local BLANK_TEXTURE = [[Interface\ChatFrame\ChatFrameBackground]]
local BUBBLE_TEXTURE = [[Interface\Tooltips\ChatBubble-Background]]
local TOOLTIP_BORDER = [[Interface\Tooltips\UI-Tooltip-Border]]

-- Bubble Data
LibChatBubble.embeds = LibChatBubble.embeds or {}
LibChatBubble.messageToGUID = LibChatBubble.messageToGUID or {}
LibChatBubble.messageToSender = LibChatBubble.messageToSender or {}
LibChatBubble.customBubbles = LibChatBubble.customBubbles or {} -- local bubble registry
LibChatBubble.numChildren = LibChatBubble.numChildren or -1 -- worldframe children
LibChatBubble.numBubbles = LibChatBubble.numBubbles or 0 -- worldframe customBubbles

-- Custom Bubble parent frame
LibChatBubble.BubbleBox = LibChatBubble.BubbleBox or CreateFrame("Frame", nil, UIParent)
LibChatBubble.BubbleBox:SetAllPoints()
LibChatBubble.BubbleBox:Hide()

-- Update frame
LibChatBubble.BubbleUpdater = LibChatBubble.BubbleUpdater or CreateFrame("Frame", nil, WorldFrame)
LibChatBubble.BubbleUpdater:SetFrameStrata("TOOLTIP")


local bubbleBox = LibChatBubble.BubbleBox
local bubbleUpdater = LibChatBubble.BubbleUpdater
local messageToGUID = LibChatBubble.messageToGUID
local messageToSender = LibChatBubble.messageToSender

local minsize, maxsize, fontsize = 12, 16, 12 -- bubble font size
local offsetX, offsetY = 0, -100 -- bubble offset from its original position

local getPadding = function()
	return fontsize / 1.2
end

-- let the bubble size scale from 400 to 660ish (font size 22)
local getMaxWidth = function()
	return 400 + math_floor((fontsize - 12)/22 * 260)
end

local getBackdrop = function(scale) 
	return {
		bgFile = BLANK_TEXTURE,  
		edgeFile = TOOLTIP_BORDER, 
		edgeSize = 16 * scale,
		insets = {
			left = 2.5 * scale,
			right = 2.5 * scale,
			top = 2.5 * scale,
			bottom = 2.5 * scale
		}
	}
end

------------------------------------------------------------------------------
-- 	Namebubble Detection & Update Cycle
------------------------------------------------------------------------------

-- check whether the given frame is a bubble or not
LibChatBubble.IsBubble = function(self, bubble)
	if (bubble.IsForbidden and bubble:IsForbidden()) then
		return 
	end
	local name = bubble.GetName and bubble:GetName()
	local region = bubble.GetRegions and bubble:GetRegions()
	if (name or (not region)) then 
		return 
	end
	local texture = region.GetTexture and region:GetTexture()
	return texture and (texture == BUBBLE_TEXTURE)
end

LibChatBubble.DisableBlizzard = function(self, bubble)
	local customBubble = customBubbles[bubble]

	-- Grab the original bubble's text color
	customBubble.blizzardColor[1], 
	customBubble.blizzardColor[2], 
	customBubble.blizzardColor[3] = customBubble.blizzardText:GetTextColor()

	-- Make the original blizzard text transparent
	customBubble.blizzardText:SetTextColor(r, g, b, 0)

	-- Remove all the default textures
	for region, texture in pairs(customBubbles[bubble].blizzardRegions) do
		region:SetTexture(nil)
		region:SetAlpha(0)
	end
end

LibChatBubble.EnableBlizzard = function(self, bubble)
	local customBubble = customBubbles[bubble]

	-- Restore the original text color
	customBubble.blizzardText:SetTextColor(customBubble.blizzardColor[1], customBubble.blizzardColor[2], customBubble.blizzardColor[3], 1)

	for region, texture in pairs(customBubbles[bubble].blizzardRegions) do
		region:SetTexture(texture)
	end
end

LibChatBubble.InitBubble = function(self, bubble)
	LibChatBubble.numBubbles = LibChatBubble.numBubbles + 1

	local customBubble = CreateFrame("Frame", nil, bubbleBox)
	customBubble:Hide()
	customBubble:SetFrameStrata("BACKGROUND")
	customBubble:SetFrameLevel(LibChatBubble.numBubbles%128 + 1) -- try to avoid overlapping bubbles blending into each other
	customBubble:SetBackdrop(getBackdrop(1))

	customBubble.blizzardRegions = {}
	customBubble.blizzardColor = { 1, 1, 1, 1 }
	customBubble.color = { 1, 1, 1, 1 }
	
	customBubble.text = customBubble:CreateFontString()
	customBubble.text:SetPoint("BOTTOMLEFT", 12, 12)
	customBubble.text:SetFontObject(ChatFontNormal)
	customBubble.text:SetShadowOffset(-.75, -.75)
	customBubble.text:SetShadowColor(0, 0, 0, 1)
	
	for i = 1, bubble:GetNumRegions() do
		local region = select(i, bubble:GetRegions())
		if (region:GetObjectType() == "Texture") then
			customBubble.blizzardRegions[region] = region:GetTexture()
		elseif (region:GetObjectType() == "FontString") then
			customBubble.blizzardText = region
		end
	end

	customBubbles[bubble] = customBubble

	LibChatBubble:HideBlizzard(bubble)

	if LibChatBubble.PostCreateBubble then 
		LibChatBubble.PostCreateBubble(bubble)
	end 
end

LibChatBubble.PostCreateBubble = function(self, bubble)
	if LibChatBubble.PostCreateBubbleFunc then 
		LibChatBubble.PostCreateBubbleFunc(bubble)
	end 
end 

LibChatBubble.SetBubblePostCreateFunc = function(self, func)
	LibChatBubble.PostCreateBubbleFunc = func
end 

LibChatBubble.SetBubblePostUpdateFunc = function(self, func)
	LibChatBubble.PostUpdateBubbleFunc = func
end 

LibChatBubble.UpdateBubbleVisibility = function(self)
	local _, instanceType = IsInInstance()
	if ENGINE_LEGION_720 then 
		if (instanceType == "none") then
			SetCVar("chatBubbles", 1)
			bubbleUpdater:SetScript("OnUpdate", LibChatBubble.OnUpdate)
		else
			bubbleUpdater:SetScript("OnUpdate", nil)
			SetCVar("chatBubbles", 0)
			for bubble in pairs(customBubbles) do
				customBubbles[bubble]:Hide()
			end
		end
	else
		SetCVar("chatBubbles", 1)
		bubbleUpdater:SetScript("OnUpdate", LibChatBubble.OnUpdate)
	end
end

LibChatBubble.EnableBubbleStyling = function(self)
	if ENGINE_LEGION_720 then
		LibChatBubble:RegisterEvent("PLAYER_ENTERING_WORLD", LibChatBubble.UpdateBubbleVisibility)
	end

	-- Enforcing this now
	LibChatBubble:UpdateBubbleVisibility()
end 

LibChatBubble.DisableBubbleStyling = function(self)
end 

LibChatBubble.GetAllChatBubbles = function(self)
	if GetAllChatBubbles then
		return pairs(GetAllChatBubbles())
	end 

	local chatBubbles = {}
	local ignored = {}

	local numChildren = WorldFrame:GetNumChildren()
	if (numChildren ~= self.numChildren) then
		for i = 1, numChildren do
			local frame = select(i, WorldFrame:GetChildren())
			if (not ignored[frame]) and (not bubbles[frame]) and (not frame:IsForbidden()) then

				local name = bubble.GetName and bubble:GetName()
				local region = bubble.GetRegions and bubble:GetRegions()
				if (name or (not region)) then 
					return 
				end
				local texture = region.GetTexture and region:GetTexture()
				return texture and (texture == BUBBLE_TEXTURE)

				--self:InitBubble(frame)
			end
		end
		numChildren = children
	end

	for i = 1, WorldFrame:GetNumChildren() do
		local v = select(i, WorldFrame:GetChildren())
		local b = v.isChatBubble == nil and v:GetBackdrop()
		if v.isChatBubble ~= false and b and (b.bgFile == BUBBLE_TEXTURE) then
			v.isChatBubble = true
			for i = 1, v:GetNumRegions() do
				local frame = v
				local v = select(i, v:GetRegions())
				if v:GetObjectType() == "FontString" then
					local fontstring = v
					if type(funcToCall) == "function" then
						funcToCall(frame, fontstring)
					else
						self[funcToCall](self, frame, fontstring)
					end
				end
			end
		else
			v.isChatBubble = false
		end
	end
end

LibChatBubble.OnEvent = function(self, event, ...)
	local msg, sender, _, _, _, _, _, _, _, _, _, guid = ...
	messageToGUID[msg] = guid
	messageToSender[msg] = Ambiguate(sender, "short")
end 

LibChatBubble:RegisterEvent("CHAT_MSG_SAY", "OnEvent")
LibChatBubble:RegisterEvent("CHAT_MSG_YELL", "OnEvent")
LibChatBubble:RegisterEvent("CHAT_MSG_MONSTER_SAY", "OnEvent")
LibChatBubble:RegisterEvent("CHAT_MSG_MONSTER_YELL", "OnEvent")

-- Module embedding
local embedMethods = {
	EnableBubbleStyling = true,
	DisableBubbleStyling = true,
	SetBubblePostCreateFunc = true,
	SetBubblePostUpdateFunc = true
}

LibChatBubble.Embed = function(self, target)
	for method in pairs(embedMethods) do
		target[method] = self[method]
	end
	self.embeds[target] = true
	return target
end

-- Upgrade existing embeds, if any
for target in pairs(LibChatBubble.embeds) do
	LibChatBubble:Embed(target)
end
