-- @include libs/utils.txt
-- @client
require("/koptilnya/libs/utils.txt")

EngineSound = class("EngineSound")

accessorFunc(EngineSound, "_masterVolume", "MasterVolume", 1)
accessorFunc(EngineSound, "_parent", "Parent", chip())

local function fadeIn(rpm, range)
    local fadeIn = 1

    if range and range[1] ~= range[2] then
        fadeIn = math.min(math.max((rpm + (range[2] - range[1] * 2)) / (range[2] - range[1]), 1) - 1, 1)
    elseif range and range[1] == range[2] then
        fadeIn = rpm >= range[1] and 1 or 0
    end

    return fadeIn
end

local function fadeOut(rpm, range)
    local fadeOut = 1

    if range and range[1] ~= range[2] then
        fadeOut = math.min(math.max((rpm + (range[1] - range[2] * 2)) / (range[1] - range[2]), 1) - 1, 1)
    elseif range and range[1] == range[2] then
        fadeOut = rpm >= range[1] and 1 or 0
    end

    return fadeOut
end

function EngineSound:initialize(soundsMap)
    self.pitchDamping = 0.2
    self.volumeDamping = 0.3

    self._rpm = 0
    self._soundsMap = soundsMap

    for k, v in pairs(soundsMap) do
        bass.loadURL(v.link, "3d noblock", function(snd, err, errtxt)
            if snd then
                snd:setPos(self:getParent():getPos())
                snd:setLooping(true)
                snd:setVolume(0)

                v.source = snd
                v.lastPitch = 1
                v.lastVolume = 0
            elseif errtext then
                error(errtxt)
            end
        end)
    end

    hook.add("think", "EngineSound_think", function()
        for _, v in pairs(self._soundsMap) do
            if v.source then
                v.source:setPos(self:getParent():getPos())

                local fadeIn = fadeIn(self:getRPM(), v.fadeIn)
                local fadeOut = fadeOut(self:getRPM(), v.fadeOut)
                local targetVolume = self:getMasterVolume() * (fadeIn + fadeOut - 1)
                local targetPitch = self:getRPM() / v.rootPitch

                local pitch = math.lerp(self.pitchDamping, v.lastPitch, targetPitch)
                local volume = math.lerp(self.volumeDamping, v.lastVolume, targetVolume)

                v.source:setVolume(volume)
                v.source:setPitch(pitch)

                v.lastVolume = volume
                v.lastPitch = pitch
            end
        end
    end)
end

function EngineSound:setRPM(rpm)
    self._rpm = math.max(rpm, 0)
end

function EngineSound:getRPM()
    return self._rpm
end