/*
 * Copyright (C) 2024 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License")
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.net.module.util

import com.android.net.module.util.DnsUtils.equalsDnsLabelIgnoreDnsCase
import com.android.net.module.util.DnsUtils.equalsIgnoreDnsCase
import com.android.net.module.util.DnsUtils.toDnsLabelsUpperCase
import com.android.net.module.util.DnsUtils.toDnsUpperCase
import com.android.testutils.DevSdkIgnoreRunner
import org.junit.Assert.assertArrayEquals
import org.junit.Assert.assertEquals
import org.junit.Assert.assertFalse
import org.junit.Assert.assertTrue
import org.junit.Test
import org.junit.runner.RunWith

@RunWith(DevSdkIgnoreRunner::class)
class DnsUtilsTest {
    @Test
    fun testToDnsUpperCase() {
        assertEquals("TEST", toDnsUpperCase("TEST"))
        assertEquals("TEST", toDnsUpperCase("TeSt"))
        assertEquals("TEST", toDnsUpperCase("test"))
        assertEquals("TÉST", toDnsUpperCase("TÉST"))
        assertEquals("ţéST", toDnsUpperCase("ţést"))
        // Unicode characters 0x10000 (𐀀), 0x10001 (𐀁), 0x10041 (𐁁)
        // Note the last 2 bytes of 0x10041 are identical to 'A', but it should remain unchanged.
        assertEquals(
            "TEST: -->\ud800\udc00 \ud800\udc01 \ud800\udc41<-- ",
                toDnsUpperCase("Test: -->\ud800\udc00 \ud800\udc01 \ud800\udc41<-- ")
        )
        // Also test some characters where the first surrogate is not \ud800
        assertEquals(
            "TEST: >\ud83c\udff4\udb40\udc67\udb40\udc62\udb40" +
                "\udc77\udb40\udc6c\udb40\udc73\udb40\udc7f<",
                toDnsUpperCase(
                    "Test: >\ud83c\udff4\udb40\udc67\udb40\udc62\udb40" +
                        "\udc77\udb40\udc6c\udb40\udc73\udb40\udc7f<"
                )
        )
    }

    @Test
    fun testToDnsLabelsUpperCase() {
        assertArrayEquals(
            arrayOf("TEST", "TÉST", "ţéST"),
            toDnsLabelsUpperCase(arrayOf("TeSt", "TÉST", "ţést"))
        )
    }

    @Test
    fun testEqualsIgnoreDnsCase() {
        assertTrue(equalsIgnoreDnsCase("TEST", "Test"))
        assertTrue(equalsIgnoreDnsCase("TEST", "test"))
        assertTrue(equalsIgnoreDnsCase("test", "TeSt"))
        assertTrue(equalsIgnoreDnsCase("Tést", "tést"))
        assertFalse(equalsIgnoreDnsCase("ŢÉST", "ţést"))
        // Unicode characters 0x10000 (𐀀), 0x10001 (𐀁), 0x10041 (𐁁)
        // Note the last 2 bytes of 0x10041 are identical to 'A', but it should remain unchanged.
        assertTrue(equalsIgnoreDnsCase(
                "test: -->\ud800\udc00 \ud800\udc01 \ud800\udc41<-- ",
                "Test: -->\ud800\udc00 \ud800\udc01 \ud800\udc41<-- "
        ))
        // Also test some characters where the first surrogate is not \ud800
        assertTrue(equalsIgnoreDnsCase(
                "test: >\ud83c\udff4\udb40\udc67\udb40\udc62\udb40" +
                        "\udc77\udb40\udc6c\udb40\udc73\udb40\udc7f<",
                "Test: >\ud83c\udff4\udb40\udc67\udb40\udc62\udb40" +
                        "\udc77\udb40\udc6c\udb40\udc73\udb40\udc7f<"
        ))
    }

    @Test
    fun testEqualsLabelIgnoreDnsCase() {
        assertTrue(equalsDnsLabelIgnoreDnsCase(arrayOf("TEST", "Test"), arrayOf("test", "test")))
        assertFalse(equalsDnsLabelIgnoreDnsCase(arrayOf("TEST", "Test"), arrayOf("test")))
        assertFalse(equalsDnsLabelIgnoreDnsCase(arrayOf("Test"), arrayOf("test", "test")))
        assertFalse(equalsDnsLabelIgnoreDnsCase(arrayOf("TEST", "Test"), arrayOf("test", "tést")))
    }
}