--[[
# Element: Raid Role Indicator

Handles the visibility and updating of an indicator based on the unit's raid assignment (main tank or main assist).

## Widget

RaidRoleIndicator - A `Texture` representing the unit's raid assignment.

## Notes

This element updates by changing the texture.

## Examples

    -- Position and size
    local RaidRoleIndicator = self:CreateTexture(nil, 'OVERLAY')
    RaidRoleIndicator:SetSize(16, 16)
    RaidRoleIndicator:SetPoint('TOPLEFT')

    -- Register it with oUF
    self.RaidRoleIndicator = RaidRoleIndicator
--]]

local _, ns = ...
local oUF = ns.oUF

local GetPartyAssignment = GetPartyAssignment
local UnitHasVehicleUI = UnitHasVehicleUI
local UnitInRaid = UnitInRaid

local MAINTANK_ICON = [[Interface\GROUPFRAME\UI-GROUP-MAINTANKICON]]
local MAINASSIST_ICON = [[Interface\GROUPFRAME\UI-GROUP-MAINASSISTICON]]

local function Update(self, event)
	local unit = self.unit

	local element = self.RaidRoleIndicator

	--[[ Callback: RaidRoleIndicator:PreUpdate()
	Called before the element has been updated.

	* self - the RaidRoleIndicator element
	--]]
	if(element.PreUpdate) then
		element:PreUpdate()
	end

	local role, isShown
	if(UnitInRaid(unit) and not UnitHasVehicleUI(unit)) then
		if(GetPartyAssignment('MAINTANK', unit)) then
			isShown = true
			element:SetTexture(MAINTANK_ICON)
			role = 'MAINTANK'
		elseif(GetPartyAssignment('MAINASSIST', unit)) then
			isShown = true
			element:SetTexture(MAINASSIST_ICON)
			role = 'MAINASSIST'
		end
	end

	if isShown then
		element:Show()
	else
		element:Hide()
	end

	--[[ Callback: RaidRoleIndicator:PostUpdate(role)
	Called after the element has been updated.

	* self - the RaidRoleIndicator element
	* role - the unit's raid assignment (string?)['MAINTANK', 'MAINASSIST']
	--]]
	if(element.PostUpdate) then
		return element:PostUpdate(role)
	end
end

local function Path(self, ...)
	--[[ Override: RaidRoleIndicator.Override(self, event, ...)
	Used to completely override the internal update function.

	* self  - the parent object
	* event - the event triggering the update (string)
	* ...   - the arguments accompanying the event
	--]]
	return (self.RaidRoleIndicator.Override or Update)(self, ...)
end

local function ForceUpdate(element)
	return Path(element.__owner, 'ForceUpdate')
end

local function Enable(self)
	local element = self.RaidRoleIndicator
	if(element) then
		element.__owner = self
		element.ForceUpdate = ForceUpdate

		self:RegisterEvent('PARTY_MEMBERS_CHANGED', Path, true)

		return true
	end
end

local function Disable(self)
	local element = self.RaidRoleIndicator
	if(element) then
		element:Hide()

		self:UnregisterEvent('PARTY_MEMBERS_CHANGED', Path)
	end
end

oUF:AddElement('RaidRoleIndicator', Path, Enable, Disable)