local function defaultTimeout() end

---@class Timer
---@field duration number
---@field time number
---@field oneShot boolean
---@field timeout function
---@field data table
---@field paused boolean
Timer = {
    duration = 1,
    time = 1,
    oneShot = false,
    timeout = defaultTimeout,
    data = {},
    paused = true
}

---@param duration number|nil
---@param oneShot boolean|nil
---@param timeout function|nil
---@param data table|nil
---@return Timer
function Timer:new( duration, oneShot, timeout, data )
    local timer = {
        duration = duration or self.duration,
        time = duration or self.duration,
        oneShot = oneShot or self.oneShot,
        timeout = timeout or self.timeout,
        data = data or self.data,
        paused = self.paused,
    }
    setmetatable( timer, { __index = self } )

    return timer
end

---@param dt number
function Timer:tick( dt )
    if self.paused then
        return
    end

    self.time = self.time - dt

    if self.time <= 0 then
        self.timeout( self.data )

        if self.oneShot then
            self.paused = true
            self.time = 0
        else
            self.time = self.duration + self.time
        end
    end
end

---@param duration number|nil
function Timer:start( duration )
    self.paused = false
    if duration ~= nil then
        self.duration = duration
    end
    self.time = self.duration
end

---@param emit boolean
function Timer:stop( emit )
    self.paused = true
    self.time = 0
    if emit then
        self.timeout( self.data )
    end
end

function Timer:elapsed()
    return self.duration - self.time
end