Dispatcher.lua

local _M = {}

local listeners = {}

if not table.deepcopy then
    function table.deepcopy(t)
        if type(t) ~= 'table' then return t end
        local mt = getmetatable(t)
        local res = {}
        for k,v in pairs(t) do
            if type(v) == 'table' then
                v = table.deepcopy(v)
            end
            res[k] = v
        end
        setmetatable(res,mt)
        return res
    end
end

function _M.addListener(name, listener)
    if not name or not listener then return end
    if not listeners[name] then listeners[name] = {} end
    table.insert(listeners[name], listener)
end

function _M.removeListener(name, listener)
    if not name or not listener or not listeners[name] then return end
    local ind = table.indexOf(listeners[name], listener)
    if ind then table.remove(listeners[name], ind) end
end

function _M.dispatch(name, params)
    if not name or not listeners[name] then return end
    local l = listeners[name]
    for i = 1, #l do
        l[i](params and table.deepcopy(params))
    end
end

return _M