packages/pigeon/platform_tests/android_kotlin_unit_tests/android/app/src/test/java/com/example/android_kotlin_unit_tests/NullableReturnsTest.kt

// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package com.example.android_kotlin_unit_tests

import io.flutter.plugin.common.BinaryMessenger
import io.mockk.every
import io.mockk.mockk
import io.mockk.slot
import io.mockk.verify
import junit.framework.TestCase
import org.junit.Test

class NullableReturnsTest: TestCase() {
    @Test
    fun testNullableParameterHost() {
        val binaryMessenger = mockk<BinaryMessenger>(relaxed = true)
        val api = mockk<NullableReturnHostApi>(relaxed = true)

        val output = 1L

        val channelName = "dev.flutter.pigeon.NullableReturnHostApi.doit"
        val handlerSlot = slot<BinaryMessenger.BinaryMessageHandler>()

        every { binaryMessenger.setMessageHandler(channelName, capture(handlerSlot)) } returns Unit
        every { api.doit() } returns output

        NullableReturnHostApi.setUp(binaryMessenger, api)

        val codec = PrimitiveHostApi.codec
        val message = codec.encodeMessage(null)
        message?.rewind()
        handlerSlot.captured.onMessage(message) {
            it?.rewind()
            @Suppress("UNCHECKED_CAST")
            val wrapped = codec.decodeMessage(it) as HashMap<String, Any>?
            assertNotNull(wrapped)
            wrapped?.let {
                assertEquals(output, wrapped["result"])
            }
        }

        verify { binaryMessenger.setMessageHandler(channelName, handlerSlot.captured) }
        verify { api.doit() }
    }

    @Test
    fun testNullableParameterFlutter() {
        val binaryMessenger = mockk<BinaryMessenger>()
        val api = NullableReturnFlutterApi(binaryMessenger)

        val output = 12L

        every { binaryMessenger.send(any(), any(), any()) } answers {
            val codec = NullableReturnFlutterApi.codec
            val reply = arg<BinaryMessenger.BinaryReply>(2)
            val replyData = codec.encodeMessage(output)
            replyData?.position(0)
            reply.reply(replyData)
        }

        var didCall = false
        api.doit {
            didCall = true
            assertEquals(output, it)
        }

        assertTrue(didCall)
    }
}