-- @version 1.0.1
-- @location /libs/

local utils = {}

local lastTick = os.clock()
local deltaTime = 0
local tickCount = 0

local lastTickTime = os.clock()
local lastServerTickTime = os.clock()
local lastTickDayTime = nil
local tps = 20

local tickRates = {}
local nextIndex = 0
local timeLastTimeUpdate = -1
local timeGameJoined = os.clock() * 1000

registerClientTick(function()
    tickCount = tickCount + 1
    lastTickTime = os.clock()
end)

registerServerSetTimeEvent(function(dayTime, gameTime, tickDayTime)
    local now = os.clock() * 1000

    if timeLastTimeUpdate ~= -1 then
        local timeElapsed = (now - timeLastTimeUpdate) / 1000

        local currentTps = 20.0 / timeElapsed
        if currentTps > 20 then currentTps = 20 end
        if currentTps < 0 then currentTps = 0 end

        tickRates[nextIndex] = currentTps
        nextIndex = (nextIndex + 1) % 20
    end

    timeLastTimeUpdate = now
    lastTickDayTime = tickDayTime
end)

registerWorldRenderer(function()
    local currentTick = os.clock()
    deltaTime = currentTick - lastTick
    lastTick = currentTick
end)

---Reurns sqrt dist between points
---@param pos1 table
---@param pos2 table
---@return number
function utils.getDistance(pos1, pos2)
    return math.sqrt((pos1.x - pos2.x) ^ 2 + (pos1.y - pos2.y) ^ 2 + (pos1.z - pos2.z) ^ 2)
end

---comment
---@param o table
---@param depth number|nil
---@return unknown
function utils.dump(o, depth)
    depth = depth or 0
    local indent = string.rep('  ', depth)

    if type(o) == 'table' then
        local s = '{\n'
        for k, v in pairs(o) do
            if type(k) ~= 'number' then k = '"' .. k .. '"' end
            s = s .. indent .. '  [' .. k .. '] = ' .. utils.dump(v, depth + 1) .. ',\n'
        end
        return s .. indent .. '}'
    else
        return tostring(o)
    end
end

---Returns seconds between frames
---@return integer
function utils.deltaTime()
    return deltaTime
end

---Rounds a value to n after comma
---@param n number
---@param decimals number
---@return unknown
function utils.round(n, decimals)
    local factor = 10 ^ (decimals or 0)
    return math.floor(n * factor + 0.5) / factor
end

---Normalizes minecraft yaw
---@param yaw number
---@return number
function utils.normalizeYaw(yaw)
    yaw = yaw % 360
    if yaw > 180 then
        yaw = yaw - 360
    end
    return yaw
end

---Returns ticks since library load
---@return integer
function utils.tickCount()
    return tickCount
end

---Returns date from unix time
---@param stamp number
---@return string|osdate
function utils.timestampToDate(stamp)
    stamp = math.floor(stamp / 1000)
    return os.date("%Y-%m-%d %H:%M:%S", stamp)
end

---Returns fps of the game
---@return integer
function utils.getFPS()
    if deltaTime > 0 then
        return math.ceil(1 / deltaTime)
    end
    return 0
end

---Returns current TPS (Ticks Per Second)
---@return number
function utils.getTPS()
    if os.clock() * 1000 - timeGameJoined < 4000 then
        return 20
    end

    local numTicks = 0
    local sumTickRates = 0

    for _, tickRate in ipairs(tickRates) do
        if tickRate and tickRate > 0 then
            sumTickRates = sumTickRates + tickRate
            numTicks = numTicks + 1
        end
    end

    if numTicks > 0 then
        return sumTickRates / numTicks
    end
    return 0
end

---Returns time since last tick was received (in seconds)
---@return number
function utils.getTimeSinceLastTick()
    if os.clock() * 1000 - timeGameJoined < 4000 then
        return 0
    end
    return (os.clock() * 1000 - timeLastTimeUpdate) / 1000
end

return utils