ViewTest.kt

import org.junit.Assert.*
import org.junit.Before
import org.junit.Test

class ViewTest {

    private lateinit var firstColour: Colour
    private lateinit var secondColour: Colour
    private lateinit var overlappedColour: Colour

    private lateinit var emptyView: View
    private lateinit var view1WithOneChart: View
    private lateinit var view2WithNonOverlappedCharts: View
    private lateinit var view3WithOverlappedCharts: View

    private lateinit var pointNotInView3: Coordinate
    private lateinit var pointInView3FirstChart: Coordinate
    private lateinit var pointInView3SecondChart: Coordinate
    private lateinit var pointInView3OverlappedChart: Coordinate

    @Before
    fun setup() {
        val rectangle1 = Rectangle(Coordinate(0, 0), Coordinate(50, 50))
        val rectangle2 = Rectangle(Coordinate(25, 25), Coordinate(75, 75))
        val rectangle3 = Rectangle(Coordinate(80, 80), Coordinate(100, 100))

        firstColour = Colour(255, 0, 0)
        secondColour = Colour(0, 0, 255)
        overlappedColour = Colour(128, 0, 128)

        emptyView = View(emptyList())
        view1WithOneChart = View(listOf(Chart(rectangle1, firstColour)))
        view2WithNonOverlappedCharts =
            View(listOf(Chart(rectangle1, firstColour), Chart(rectangle3, secondColour)))
        view3WithOverlappedCharts =
            View(listOf(Chart(rectangle1, firstColour), Chart(rectangle2, secondColour)))

        pointNotInView3 = Coordinate(80, 80)
        pointInView3FirstChart = Coordinate(0, 0)
        pointInView3SecondChart = Coordinate(60, 60)
        pointInView3OverlappedChart = Coordinate(35, 35)

    }

    @Test
    fun `View doChartsOverlap should return false if contains zero or one chart`() {
        assertFalse(emptyView.doChartsOverlap())
        assertFalse(view1WithOneChart.doChartsOverlap())
    }

    @Test
    fun `View doChartsOverlap should return false if contains two non-overlapped charts`() {
        assertFalse(view2WithNonOverlappedCharts.doChartsOverlap())
    }

    @Test
    fun `View doChartsOverlap should return true if contains two overlapped charts`() {
        assertTrue(view3WithOverlappedCharts.doChartsOverlap())
    }

    @Test(expected = IllegalArgumentException::class)
    fun `View with more than 2 chars should throw exception`() {
        val chart = Chart(Rectangle(Coordinate(0, 0), Coordinate(50, 50)), Colour(255, 0, 0))
        View(listOf(chart, chart, chart))
    }

    @Test
    fun `View getColour should return null if contains 0 chart`() {
        assertNull(emptyView.getColour(0, 0))
    }

    @Test
    fun `View getColour should return null if the given point is not in charts`() {
        with (pointNotInView3) {
            assertNull(view3WithOverlappedCharts.getColour(x, y))
        }
    }

    @Test
    fun `View getColour should return chart colour if the given point is found in only this chart`() {
        with (pointInView3FirstChart) {
            assertEquals(firstColour, view3WithOverlappedCharts.getColour(x, y))
        }
        with (pointInView3SecondChart) {
            assertEquals(secondColour, view3WithOverlappedCharts.getColour(x, y))
        }
    }

    @Test
    fun `View getColour should return overlapped colour if the given point is found in overlapped area`() {
        with (pointInView3OverlappedChart) {
            assertEquals(overlappedColour, view3WithOverlappedCharts.getColour(x, y))
        }
    }
}