import ddf.minim.Minim
import ddf.minim.analysis.FFT
import ddf.minim.analysis.LanczosWindow
import org.openrndr.application
import org.openrndr.extra.minim.minim
import org.openrndr.math.map
import kotlin.math.ln

fun main() = application {
    configure {
        width = 1280
        height = 720
    }

    program {
        val minim = minim()
        if (minim.lineOut == null) {
            application.exit()
        }

        val lineIn = minim.getLineIn(Minim.MONO, 2048, 48000f)
        if (lineIn == null) {
            application.exit()
        }
        val fft = FFT(lineIn.bufferSize(), lineIn.sampleRate())
        fft.window(LanczosWindow())
        extend {
            fft.forward(lineIn.mix)
            for (i in 0 until 200) {
                val bandDB = 20.0 * ln(2.0 * fft.getBand(i) / fft.timeSize())
                drawer.rectangle(i * 5.0, height / 2.0, 5.0, bandDB.map(0.0, -150.0, 0.0, -height / 8.0))
            }
        }
    }
}