-- incoming.lua
-- 2020 Aleksi Blinnikka
local _;
local UnitGUID, UnitIsEnemy = UnitGUID, UnitIsEnemy;

local _, addon = ...;
local guids = addon.FrameGuids;
local abilities = {
    [260741] = true, -- Jagged Nettles (Waycrest Manor)
    [342675] = true, -- Bone Spear (Theater of Pain)
    [320788] = true, -- Frozen Binds (Necrotic Wake)
};

local frame = CreateFrame("Frame", "kehysIncoming");

local function event(_, event, target, cast, id)
    if event == "PLAYER_REGEN_ENABLED" then
        for _, f in pairs(guids) do
            f.incoming = {};
        end
        return
    end
    if abilities[id] and UnitIsEnemy("player", target) then
        local f = guids[UnitGUID(target .. "target")];
        if f then
            if event == "UNIT_SPELLCAST_START" then
                if f.incoming[id] then
                    f.incoming[id] = f.incoming[id] + 1;
                else
                    f.incoming[id] = 1;
                end
            elseif f.incoming[id] then
                f.incoming[id] = f.incoming[id] - 1;
                if f.incoming[id] == 0 then
                    f.incoming[id] = nil;
                end
            end
        end
    end
end

local function setup()
    frame:UnregisterAllEvents();
    frame:SetScript("OnEvent", event);
    frame:RegisterEvent("UNIT_SPELLCAST_START");
    frame:RegisterEvent("UNIT_SPELLCAST_CHANNEL_START");
    frame:RegisterEvent("UNIT_SPELLCAST_CHANNEL_STOP");
    frame:RegisterEvent("UNIT_SPELLCAST_STOP");
    frame:RegisterEvent("UNIT_SPELLCAST_INTERRUPTED");
    frame:RegisterEvent("UNIT_SPELLCAST_FAILED");
    frame:RegisterEvent("UNIT_SPELLCAST_FAILED_QUIET");
    frame:RegisterEvent("PLAYER_REGEN_ENABLED");
end

frame:SetScript("OnEvent", setup);
frame:RegisterEvent("PLAYER_LOGIN");