package org.meshbay.client

import org.junit.Assert.assertArrayEquals
import org.junit.Assert.assertEquals
import org.junit.Assert.assertNull
import org.junit.Test
import org.meshbay.client.photos.ByteRange

class ByteRangeTest {
    @Test fun `a range is read as the upload asks for it`() {
        assertEquals(0L..1023L, ByteRange.parse("bytes=0-1023", 5000))
        assertEquals(4096L..4999L, ByteRange.parse("bytes=4096-", 5000))
        assertEquals("the last chunk may ask past the end", 4096L..4999L, ByteRange.parse("bytes=4096-8191", 5000))
    }

    @Test fun `what cannot be served is refused`() {
        assertNull(ByteRange.parse(null, 10))
        assertNull(ByteRange.parse("bytes=10-20", 10))
        assertNull(ByteRange.parse("bytes=5-2", 10))
        assertNull(ByteRange.parse("bytes=0-1,4-5", 10))
        assertNull(ByteRange.parse("bytes=-5", 10))
        assertNull(ByteRange.parse("items=0-1", 10))
    }

    @Test fun `a slice holds exactly those bytes`() {
        val data = ByteArray(100_000) { (it % 251).toByte() }
        val got = ByteRange.slice(data.inputStream(), 70_000L..99_999L).readBytes()
        assertArrayEquals(data.copyOfRange(70_000, 100_000), got)
        assertArrayEquals(data.copyOfRange(10, 12), ByteRange.slice(data.inputStream(), 10L..11L).readBytes())
    }
}