package com.mindmachine.mvp

import com.mindmachine.mvp.domain.VisualPattern
import com.mindmachine.mvp.session.computeVisualAlpha
import org.junit.Assert.assertEquals
import org.junit.Assert.assertTrue
import org.junit.Test

class VisualSignalTest {

    @Test
    fun flashPatternAlternatesBetweenIntensityAndOff() {
        val intensity = 70
        val hz = 10f

        val on = computeVisualAlpha(
            visualPattern = VisualPattern.FLASH,
            frameTimeNanos = 0L,
            blinkFrequencyHz = hz,
            intensityPercent = intensity
        )

        val off = computeVisualAlpha(
            visualPattern = VisualPattern.FLASH,
            frameTimeNanos = 75_000_000L,
            blinkFrequencyHz = hz,
            intensityPercent = intensity
        )

        assertEquals(0.7f, on, 0.0001f)
        assertEquals(0f, off, 0.0001f)
    }

    @Test
    fun pulsePatternStaysWithinZeroAndIntensity() {
        val intensity = 60

        val atStart = computeVisualAlpha(
            visualPattern = VisualPattern.PULSE,
            frameTimeNanos = 0L,
            blinkFrequencyHz = 3f,
            intensityPercent = intensity
        )
        val quarterCycle = computeVisualAlpha(
            visualPattern = VisualPattern.PULSE,
            frameTimeNanos = 83_333_333L,
            blinkFrequencyHz = 3f,
            intensityPercent = intensity
        )

        assertTrue(atStart in 0f..0.6f)
        assertTrue(quarterCycle in 0f..0.6f)
        assertTrue(quarterCycle > atStart)
    }

    @Test
    fun intensityZeroAlwaysReturnsZero() {
        val alpha = computeVisualAlpha(
            visualPattern = VisualPattern.FLASH,
            frameTimeNanos = 123_000_000L,
            blinkFrequencyHz = 8f,
            intensityPercent = 0
        )

        assertEquals(0f, alpha, 0f)
    }
}