if SERVER then return end

flomp = flomp or {} local f = flomp

flomp.emitter = ParticleEmitter(EyePos(), false)

f.FFT = {}
f.FFT_Size = 256

f.FFT_Bass_1 = 0
f.FFT_Bass_2 = 0

f.max_volume = 0
f.scale = 1
f.eye_angles = Angle(0)
f.eye_origin = vector_origin
f.vol_multplier = 1

f.fft_detail = 10
f.mul_fft = f.FFT_Size/f.fft_detail

for i = 1, f.FFT_Size do
    f.FFT[i] = 0
end

function flomp.SetSource(var)
    var = type(var) == "number" and Entity(var) or var
    if type(var) == "Vector" or (IsEntity(var) and var:IsValid()) then
        f.source = var
    end
end

function flomp.SetScale(n)
    f.scale = n
end

function flomp.SetVolumeInputScale(n)
    f.vol_multplier = n
end

function flomp.GetSourcePos()
    return type(f.source) == "Vector" and f.source or IsEntity(f.source) and f.source:IsValid() and f.source:GetPos() or vector_origin
end

function flomp.GetAverage(istart, iend)
    istart = math.Round(math.Clamp(istart, 1, f.FFT_Size))
    iend = math.Round(math.Clamp(iend, 1, f.FFT_Size))
    local n = 0
    for i=istart, iend do
    --  if f.FFT[i] then
            n = n + f.FFT[i]
--      end
    end

    local div = (iend - istart)

    return div == 0 and 0 or (n / div)
end

function flomp.IsAround(number, min, max)
    return number > min and number < max and true or false
end

flomp.powscale = 0.5

function flomp.ScaleVolume(volume)
    return (volume ^ flomp.powscale) * f.vol_multplier * 7
end

function flomp.Spectrum2D()
    do return end
    --if bawss and bawss.channel then bawss.channel:stop() bawss = nil end -- declan interuption protection

    local h = ScrH() + -400
    local w = ScrW()
    local volume = 0

    for fr = 1, f.FFT_Size do
        volume = f.ScaleVolume(f.FFT[fr])

        surface.SetDrawColor(volume,volume,255*volume,255)
        surface.DrawLine(
            (w+fr)-ScrW(), h,
            (w+fr)-ScrW(), h-(volume*50)
        )
    end
end

function flomp.ParticleThink(data)
    f.FFT = data

    f.FFT_Bass_1 = flomp.GetAverage(1, 6)

    for i = 1, 4 do

        local fr = (i * 256)

        local volume = f.ScaleVolume(f.FFT[math.Clamp(math.Round(i*f.mul_fft), 1, f.FFT_Size)])

        if volume < 0.01 then continue end

        local n_fr = -(fr-30) + f.FFT_Size -- negative fr, f.FFT_Size to 0

        local f_fr = (fr-30)/f.FFT_Size -- fraction fr, 0, 1
        local nf_fr = n_fr/f.FFT_Size -- negative fraction, 1, 0

        for i = 1, math.Clamp(math.Round(volume*4),0,15) do

            local size = (f.FFT_Bass_1 * 20 ^ 1.5)
            local color = HSVToColor(((CurTime()*10)+(f_fr*40))%360, 0.3, 1)
            local velocity = ((f.eye_origin - f.GetSourcePos() ):Normalize() * 2 + VectorRand()):GetNormal()* volume ^ 1.3

            local particle = f.emitter:Add("particle/Particle_Glow_04_Additive", f:GetSourcePos() + (velocity*5*f.scale))

            particle:SetVelocity(velocity*500*f.scale)

            particle:SetLifeTime(0)
            particle:SetDieTime(math.Clamp(volume*0.2, 0.1, 0.8))

            particle:SetStartLength(size*7*f.scale)
            particle:SetEndLength(size*2*f.scale)
            particle:SetStartSize(size*f.scale)
            particle:SetEndSize(0)

            particle:SetStartAlpha(255)
            particle:SetEndAlpha(0)

            particle:SetAirResistance(math.Clamp((-size+800), 10, 1200)*f.scale)
            --particle:SetGravity((VectorRand()*50)*f.scale)

            particle:SetColor(color.r, color.g, color.b)
            particle:SetCollide(true)
            particle:SetBounce(0.1)
        end
    end
end

f.smooth_pp = 0
f.look_at_mult = 1

function flomp.DrawPostProcess()
    local w = ScrW()
    local h = ScrH()

    local vec2 = f.GetSourcePos():ToScreen()

    local m = math.max(f.eye_angles:Forward():DotProduct((f.GetSourcePos()-f.eye_origin):Normalize()), 0) ^ 3
    f.look_at_mult = m
    m = m * (f.sound_vol * 2) ^ 2

    --m = m * math.Clamp((-f.eye_origin:Distance(f.GetSourcePos()) / 15000) + 1, 0, 1)

    if m < 0.001 then return end

    m = math.Clamp(m, 0, 1)

    local vol = f.FFT_Bass_1
    local darkness = (-m+1)

    local avr = math.Clamp(vol * 2  - 0.1,0,1) * m
    local blur = math.Clamp((vol*-0.5)+1, 0.2, 1)
    local invert = (vol*-10+1)

    local angle = VectorRand() * f.GetAverage(3, 7) ^ 1.5 * m
    angle.x = math.Clamp(angle.x, -0.2, 0.2)
    angle.y = math.Clamp(angle.y, -0.2, 0.2)
    angle.z = 0
    LocalPlayer():SetEyeAngles(LocalPlayer():EyeAngles() + angle)

    f.smooth_pp = f.smooth_pp + ((avr - f.smooth_pp)*FrameTime()*10)

    local mscale = m * f.vol_multplier

    local tbl= {}
    tbl[ "$pp_colour_addr" ] = 3/255*m
    tbl[ "$pp_colour_addg" ] = 0
    tbl[ "$pp_colour_addb" ] = 4/255*m
    tbl[ "$pp_colour_brightness" ] = -0.05*m
    tbl[ "$pp_colour_contrast" ] = Lerp(m, 1, 2)
    tbl[ "$pp_colour_colour" ] = 1+(0.6*m)
    tbl[ "$pp_colour_mulr" ] = 0
    tbl[ "$pp_colour_mulg" ] = 0
    tbl[ "$pp_colour_mulb" ] = 0


    --DrawMotionBlur(blur, 1, 0)
    DrawBloom(darkness, invert*(m/20), math.max(invert*20+2, 5), math.max(invert*20+10, 5), 4, 3, 1, 1, 1 )
    DrawSunbeams(darkness+0.2, math.max(vol*0.5, 0.1), 0.05 * (vol * 20) ^ 1.5, vec2.x / ScrW(), vec2.y / ScrH())
    DrawColorModify(tbl)
    DrawToyTown(Lerp(avr, 0, 10), ScrH()*0.55)

    materials.SetSkyColor(Vector()*(darkness ^ 2))
    --print(blur)
end

hook.Add("HUDPaint", "flomp_Helper", flomp.Spectrum2D)
hook.Add("SpotifySpectrum", "flomp_Think", flomp.ParticleThink)
hook.Add("RenderScreenspaceEffects", "flomp_RenderScreenspaceEffects", flomp.DrawPostProcess)


hook.Add("RenderScene", "flomp_CalcView", function(pos, ang)
    f.eye_origin = pos
    f.eye_angles = ang
end)

local voldata = Vector(1,1,1) -- V, L, R

local function calcsource(eye, rgt, src, dist, fwd, vel)
    local vol = math.Clamp(-((eye - src):Length() / dist) + 1, 0, 1)
    local dot = rgt:Dot((src - eye):Normalize())

    local left = math.Clamp(-dot, 0, 1) + 0.5
    local right = math.Clamp(dot, 0, 1) + 0.5

    if vol ~= 0 then
    return vol, -left + right
    end
end

function GetVolumeData(source, falloff)
    local ply = LocalPlayer()
    return calcsource(ply:EyePos(),f.eye_angles:Right(), source, falloff, f.eye_angles:Forward(), ply:GetVelocity())
end

f.sound_vol = 1

hook.Add("Think","flomp_volume",function()
    local vol, panning = GetVolumeData(flomp.GetSourcePos(), 4000)

    if vol then
        f.sound_vol = vol
        vol = vol * f.look_at_mult

        BlahSetVolume(vol^1.5)
        BlahSetPanning(panning)
    end
end)

flomp.SetSource(Entity(187))
flomp.SetVolumeInputScale(1)

hook.Add("HUDPaintBackground", "itsaparty")
hook.Add("CalcView", "itsaparty")