package com.hawhamburg.micr0bu

import com.hawhamburg.micr0bu.domain.vam.VamGenerationRules
import com.hawhamburg.micr0bu.domain.vam.VamGenerationRules.Kinematics
import org.junit.Assert.assertFalse
import org.junit.Assert.assertTrue
import org.junit.Test

/** TS 103 300-3 clause 6.4 items 1 to 4, with the Table 16/17 values. */
class VamGenerationRulesTest {

    private val here = Kinematics(53.5546667, 10.0223889, speedMps = 3.0, headingDeg = 90.0)

    private fun sentAt(ms: Long, k: Kinematics = here) = VamGenerationRules().apply { onSent(ms, k, withLowFrequency = true) }

    @Test
    fun `the first VAM is always due`() {
        assertTrue(VamGenerationRules().due(0, here))
    }

    @Test
    fun `nothing is due within T_GenVamMin even after a big jump`() {
        assertFalse(sentAt(1_000).due(1_050, here.copy(latitude = here.latitude + 0.001)))
    }

    @Test
    fun `a stationary VRU gets one VAM every T_GenVamMax`() {
        val rules = sentAt(1_000)
        assertFalse(rules.due(5_900, here))
        assertTrue(rules.due(6_001, here))
    }

    @Test
    fun `position, speed and heading changes trigger past their thresholds only`() {
        val rules = sentAt(1_000)
        // ~3.3 m north: under 4 m. ~5.6 m: over.
        assertFalse(rules.due(2_000, here.copy(latitude = here.latitude + 0.00003)))
        assertTrue(rules.due(2_000, here.copy(latitude = here.latitude + 0.00005)))
        assertFalse(rules.due(2_000, here.copy(speedMps = 3.4)))
        assertTrue(rules.due(2_000, here.copy(speedMps = 3.6)))
        assertFalse(rules.due(2_000, here.copy(headingDeg = 93.0)))
        assertTrue(rules.due(2_000, here.copy(headingDeg = 95.0)))
    }

    @Test
    fun `heading change is measured the short way round north`() {
        val rules = sentAt(1_000, here.copy(headingDeg = 358.0))
        assertFalse(rules.due(2_000, here.copy(headingDeg = 1.0)))  // 3 degrees across north
        assertTrue(rules.due(2_000, here.copy(headingDeg = 3.0)))   // 5 degrees
    }

    @Test
    fun `the low-frequency container goes with the first VAM, then every T_GenVamLFMin`() {
        val rules = VamGenerationRules()
        assertTrue(rules.includeLowFrequency(0))
        rules.onSent(0, here, withLowFrequency = true)
        assertFalse(rules.includeLowFrequency(1_999))
        assertTrue(rules.includeLowFrequency(2_000))
    }
}