MindMachine/app/src/test/java/com/mindmachine/mvp/VisualSignalTest.kt

package com.mindmachine.mvp

import com.mindmachine.mvp.session.FlashColor
import com.mindmachine.mvp.session.computeSplitFlashFrame
import org.junit.Assert.assertEquals
import org.junit.Test

class VisualSignalTest {

    @Test
    fun splitFlashPattern_cycles_redGreen_black_greenRed_black() {
        val intervalMs = 100

        val phase0 = computeSplitFlashFrame(frameTimeNanos = 0L, flashIntervalMs = intervalMs)
        val phase1 = computeSplitFlashFrame(frameTimeNanos = 100_000_000L, flashIntervalMs = intervalMs)
        val phase2 = computeSplitFlashFrame(frameTimeNanos = 200_000_000L, flashIntervalMs = intervalMs)
        val phase3 = computeSplitFlashFrame(frameTimeNanos = 300_000_000L, flashIntervalMs = intervalMs)

        assertEquals(FlashColor.RED, phase0.left)
        assertEquals(FlashColor.GREEN, phase0.right)

        assertEquals(FlashColor.BLACK, phase1.left)
        assertEquals(FlashColor.BLACK, phase1.right)

        assertEquals(FlashColor.GREEN, phase2.left)
        assertEquals(FlashColor.RED, phase2.right)

        assertEquals(FlashColor.BLACK, phase3.left)
        assertEquals(FlashColor.BLACK, phase3.right)
    }

    @Test
    fun interval_is_clamped_to_valid_range() {
        val tooFast = computeSplitFlashFrame(frameTimeNanos = 49_000_000L, flashIntervalMs = 1)
        val validAt50ms = computeSplitFlashFrame(frameTimeNanos = 49_000_000L, flashIntervalMs = 50)
        assertEquals(validAt50ms, tooFast)

        val tooSlow = computeSplitFlashFrame(frameTimeNanos = 2_100_000_000L, flashIntervalMs = 5000)
        val validAt2000ms = computeSplitFlashFrame(frameTimeNanos = 2_100_000_000L, flashIntervalMs = 2000)
        assertEquals(validAt2000ms, tooSlow)
    }
}