/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package mozilla.components.feature.prompts.dialog

import android.content.DialogInterface.BUTTON_NEGATIVE
import android.content.DialogInterface.BUTTON_POSITIVE
import android.os.Looper.getMainLooper
import android.os.Parcelable
import android.view.LayoutInflater
import android.widget.LinearLayout
import android.widget.TextView
import androidx.appcompat.app.AlertDialog
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import androidx.test.ext.junit.runners.AndroidJUnit4
import mozilla.components.concept.engine.prompt.Choice
import mozilla.components.feature.prompts.R
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.Companion.TYPE_GROUP
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.Companion.TYPE_MENU
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.Companion.TYPE_MENU_SEPARATOR
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.Companion.TYPE_MULTIPLE
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.Companion.TYPE_SINGLE
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.GroupViewHolder
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.MenuViewHolder
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.MultipleViewHolder
import mozilla.components.feature.prompts.dialog.ChoiceAdapter.SingleViewHolder
import mozilla.components.feature.prompts.dialog.ChoiceDialogFragment.Companion.MENU_CHOICE_DIALOG_TYPE
import mozilla.components.feature.prompts.dialog.ChoiceDialogFragment.Companion.MULTIPLE_CHOICE_DIALOG_TYPE
import mozilla.components.feature.prompts.dialog.ChoiceDialogFragment.Companion.SINGLE_CHOICE_DIALOG_TYPE
import mozilla.components.feature.prompts.dialog.ChoiceDialogFragment.Companion.newInstance
import mozilla.components.support.test.ext.appCompatContext
import mozilla.components.support.test.robolectric.testContext
import org.junit.Assert.assertEquals
import org.junit.Assert.assertFalse
import org.junit.Assert.assertNotNull
import org.junit.Assert.assertTrue
import org.junit.Before
import org.junit.Test
import org.junit.runner.RunWith
import org.mockito.Mock
import org.mockito.Mockito.doNothing
import org.mockito.Mockito.doReturn
import org.mockito.Mockito.spy
import org.mockito.Mockito.times
import org.mockito.Mockito.verify
import org.mockito.MockitoAnnotations.openMocks
import org.robolectric.Shadows.shadowOf

@RunWith(AndroidJUnit4::class)
class ChoiceDialogFragmentTest {

    @Mock private lateinit var mockFeature: Prompter
    private val item = Choice(id = "", label = "item1")
    private val subItem = Choice(id = "", label = "sub-item1")
    private val separator = Choice(id = "", label = "item1", isASeparator = true)

    @Before
    fun setup() {
        openMocks(this)
    }

    @Test
    fun `Build single choice dialog`() {

        val fragment = spy(newInstance(arrayOf(), "sessionId", "uid", true, SINGLE_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val dialog = fragment.onCreateDialog(null)

        assertNotNull(dialog)
    }

    @Test
    fun `cancelling the dialog cancels the feature`() {
        val fragment = spy(newInstance(arrayOf(), "sessionId", "uid", false, SINGLE_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val dialog = fragment.onCreateDialog(null)

        fragment.feature = mockFeature

        doReturn(appCompatContext).`when`(fragment).requireContext()

        doNothing().`when`(fragment).dismiss()

        assertNotNull(dialog)

        dialog.show()

        fragment.onCancel(dialog)

        verify(mockFeature).onCancel("sessionId", "uid")
    }

    @Test
    fun `Build menu choice dialog`() {

        val fragment = spy(newInstance(arrayOf(), "sessionId", "uid", true, MENU_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val dialog = fragment.onCreateDialog(null)

        assertNotNull(dialog)
    }

    @Test
    fun `Build multiple choice dialog`() {

        val fragment = spy(newInstance(arrayOf(), "sessionId", "uid", false, MULTIPLE_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val dialog = fragment.onCreateDialog(null)

        assertNotNull(dialog)
    }

    @Test(expected = Exception::class)
    fun `Building a unknown dialog type will throw an exception`() {

        val fragment = spy(newInstance(arrayOf(), "sessionId", "uid", true, -1))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        fragment.onCreateDialog(null)
    }

    @Test
    fun `Will show a single choice item`() {

        val choices = arrayOf(item)

        val fragment = spy(newInstance(choices, "sessionId", "uid", false, SINGLE_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val adapter = getAdapterFrom(fragment)
        val holder = adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_SINGLE) as SingleViewHolder
        val labelView = holder.labelView
        adapter.bindViewHolder(holder, 0)

        assertEquals(1, adapter.itemCount)
        assertEquals("item1", labelView.text)
    }

    @Test
    fun `Will show a menu choice item`() {

        val choices = arrayOf(item)

        val fragment = spy(newInstance(choices, "sessionId", "uid", true, MENU_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val adapter = getAdapterFrom(fragment)
        val holder = adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_MENU) as MenuViewHolder
        val labelView = holder.labelView
        adapter.bindViewHolder(holder, 0)

        assertEquals(1, adapter.itemCount)
        assertEquals("item1", labelView.text)
    }

    @Test
    fun `Will show a menu choice separator item`() {

        val choices = arrayOf(separator)

        val fragment = spy(newInstance(choices, "sessionId", "uid", false, MENU_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val adapter = getAdapterFrom(fragment)
        val holder = adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_MENU_SEPARATOR)
        adapter.bindViewHolder(holder, 0)

        assertEquals(1, adapter.itemCount)
        assertNotNull(holder.itemView)
    }

    @Test(expected = Exception::class)
    fun `Will throw an exception to try to create a invalid choice type item`() {

        val choices = arrayOf(separator)

        val fragment = spy(newInstance(choices, "sessionId", "uid", true, MENU_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val adapter = getAdapterFrom(fragment)
        adapter.onCreateViewHolder(LinearLayout(testContext), -1)
    }

    @Test
    fun `Will adapter will return correct view type `() {

        val choices = arrayOf(
            item,
            Choice(id = "", label = "item1", children = arrayOf()),
            Choice(id = "", label = "menu", children = arrayOf()),
            Choice(id = "", label = "separator", children = arrayOf(), isASeparator = true),
            Choice(id = "", label = "multiple choice")
        )

        var fragment = spy(newInstance(choices, "sessionId", "uid", false, SINGLE_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        var adapter = getAdapterFrom(fragment)
        var type = adapter.getItemViewType(0)

        assertEquals(type, TYPE_SINGLE)

        fragment = spy(newInstance(choices, "sessionId", "uid", true, MULTIPLE_CHOICE_DIALOG_TYPE))
        doReturn(appCompatContext).`when`(fragment).requireContext()

        adapter = getAdapterFrom(fragment)

        type = adapter.getItemViewType(1)
        assertEquals(type, TYPE_GROUP)

        fragment = spy(newInstance(choices, "sessionId", "uid", false, MENU_CHOICE_DIALOG_TYPE))
        doReturn(appCompatContext).`when`(fragment).requireContext()

        adapter = getAdapterFrom(fragment)

        type = adapter.getItemViewType(2)
        assertEquals(type, TYPE_MENU)

        type = adapter.getItemViewType(3)
        assertEquals(type, TYPE_MENU_SEPARATOR)

        fragment = spy(newInstance(choices, "sessionId", "uid", true, MULTIPLE_CHOICE_DIALOG_TYPE))
        doReturn(appCompatContext).`when`(fragment).requireContext()

        adapter = getAdapterFrom(fragment)

        type = adapter.getItemViewType(4)
        assertEquals(type, TYPE_MULTIPLE)
    }

    @Test
    fun `Will show a multiple choice item`() {

        val choices =
            arrayOf(Choice(id = "", label = "item1", children = arrayOf(Choice(id = "", label = "sub-item1"))))

        val fragment = spy(newInstance(choices, "sessionId", "uid", false, MULTIPLE_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val adapter = getAdapterFrom(fragment)

        val holder =
            adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_MULTIPLE) as MultipleViewHolder
        val groupHolder = adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_GROUP) as GroupViewHolder

        adapter.bindViewHolder(holder, 0)
        adapter.bindViewHolder(groupHolder, 1)

        assertEquals(2, adapter.itemCount)
        assertEquals("item1", holder.labelView.text)
        assertEquals("sub-item1", groupHolder.labelView.text.trim())
    }

    @Test
    fun `Will show a multiple choice item with selected element`() {

        val choices = arrayOf(
            Choice(
                id = "", label = "item1",
                children = arrayOf(Choice(id = "", label = "sub-item1", selected = true))
            )
        )

        val fragment = spy(newInstance(choices, "sessionId", "uid", true, MULTIPLE_CHOICE_DIALOG_TYPE))

        doReturn(appCompatContext).`when`(fragment).requireContext()

        val adapter = getAdapterFrom(fragment)

        assertEquals(2, adapter.itemCount)

        val groupHolder = adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_GROUP) as GroupViewHolder
        val holder =
            adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_MULTIPLE) as MultipleViewHolder

        adapter.bindViewHolder(groupHolder, 0)
        adapter.bindViewHolder(holder, 1)

        assertEquals("item1", (groupHolder.labelView as TextView).text)
        assertEquals("sub-item1", holder.labelView.text.trim())
        assertEquals(true, holder.labelView.isChecked)
    }

    @Test
    fun `Clicking on single choice item notifies the feature`() {

        val choices = arrayOf(item)

        val fragment = spy(newInstance(choices, "sessionId", "uid", false, SINGLE_CHOICE_DIALOG_TYPE))

        fragment.feature = mockFeature

        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = getAdapterFrom(fragment)

        val holder = adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_SINGLE) as SingleViewHolder

        adapter.bindViewHolder(holder, 0)

        holder.itemView.performClick()
        shadowOf(getMainLooper()).idle()
        verify(mockFeature).onConfirm("sessionId", "uid", choices.first())

        dialog.dismiss()
        shadowOf(getMainLooper()).idle()
        verify(mockFeature).onCancel("sessionId", "uid")
    }

    @Test
    fun `Clicking on menu choice item notifies the feature`() {

        val choices = arrayOf(item)

        val fragment = spy(newInstance(choices, "sessionId", "uid", true, MENU_CHOICE_DIALOG_TYPE))

        fragment.feature = mockFeature

        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = getAdapterFrom(fragment)

        val holder = adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_MENU)

        adapter.bindViewHolder(holder, 0)

        holder.itemView.performClick()
        shadowOf(getMainLooper()).idle()

        verify(mockFeature).onConfirm("sessionId", "uid", choices.first())

        dialog.dismiss()
        shadowOf(getMainLooper()).idle()

        verify(mockFeature).onCancel("sessionId", "uid")
    }

    @Test
    fun `Clicking on multiple choice item notifies the feature`() {

        val choices =
            arrayOf(Choice(id = "", label = "item1", children = arrayOf(subItem)))
        val fragment = spy(newInstance(choices, "sessionId", "uid", false, MULTIPLE_CHOICE_DIALOG_TYPE))

        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        val holder = adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_MULTIPLE)

        adapter.bindViewHolder(holder, 1)

        holder.itemView.performClick()

        assertTrue(fragment.mapSelectChoice.isNotEmpty())

        val positiveButton = (dialog as AlertDialog).getButton(BUTTON_POSITIVE)
        positiveButton.performClick()
        shadowOf(getMainLooper()).idle()

        verify(mockFeature).onConfirm("sessionId", "uid", fragment.mapSelectChoice.keys.toTypedArray())

        val negativeButton = dialog.getButton(BUTTON_NEGATIVE)
        negativeButton.performClick()
        shadowOf(getMainLooper()).idle()

        verify(mockFeature, times(2)).onCancel("sessionId", "uid")
    }

    @Test
    fun `Clicking on selected multiple choice item will notify feature`() {

        val choices =
            arrayOf(item.copy(selected = true))
        val fragment = spy(newInstance(choices, "sessionId", "uid", true, MULTIPLE_CHOICE_DIALOG_TYPE))

        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        val holder =
            adapter.onCreateViewHolder(LinearLayout(testContext), TYPE_MULTIPLE) as MultipleViewHolder

        adapter.bindViewHolder(holder, 0)

        assertTrue(holder.labelView.isChecked)

        holder.itemView.performClick()

        assertTrue(fragment.mapSelectChoice.isEmpty())

        val positiveButton = (dialog as AlertDialog).getButton(BUTTON_POSITIVE)
        positiveButton.performClick()
        shadowOf(getMainLooper()).idle()

        verify(mockFeature).onConfirm("sessionId", "uid", fragment.mapSelectChoice.keys.toTypedArray())
    }

    @Test
    fun `single choice item with multiple sub-menu groups`() {

        val choices = arrayOf(
            Choice(
                id = "group1",
                label = "group1",
                children = arrayOf(Choice(id = "item_group_1", label = "item group 1"))
            ),
            Choice(
                id = "group2",
                label = "group2",
                children = arrayOf(Choice(id = "item_group_2", label = "item group 2"))
            )
        )

        val fragment = spy(newInstance(choices, "sessionId", "uid", false, SINGLE_CHOICE_DIALOG_TYPE))
        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        val groupViewHolder = adapter.onCreateViewHolder(LinearLayout(testContext), adapter.getItemViewType(0))
            as GroupViewHolder

        adapter.bindViewHolder(groupViewHolder, 0)

        assertFalse(groupViewHolder.labelView.isEnabled)
        assertEquals(groupViewHolder.labelView.text, "group1")

        val singleViewHolder =
            adapter.onCreateViewHolder(LinearLayout(testContext), adapter.getItemViewType(1)) as SingleViewHolder

        adapter.bindViewHolder(singleViewHolder, 1)

        with(singleViewHolder) {
            assertTrue(labelView.isEnabled)

            val choiceGroup1 = choices[0].children!![0]
            assertEquals(labelView.text, choiceGroup1.label)

            itemView.performClick()
            verify(mockFeature).onConfirm("sessionId", "uid", choiceGroup1)
        }
    }

    @Test
    fun `disabled single choice item is not clickable`() {
        val choices = arrayOf(
            Choice(id = "item1", label = "Enabled choice"),
            Choice(id = "item2", enable = false, label = "Disabled choice")
        )

        val fragment =
            spy(newInstance(choices, "sessionId", "uid", false, SINGLE_CHOICE_DIALOG_TYPE))
        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        // test disabled item
        val disabledItemViewHolder =
            adapter.onCreateViewHolder(LinearLayout(testContext), adapter.getItemViewType(1))
                as SingleViewHolder

        adapter.bindViewHolder(disabledItemViewHolder, 1)

        with(disabledItemViewHolder) {
            assertEquals(labelView.text, "Disabled choice")
            assertFalse(labelView.isEnabled)
            assertFalse(itemView.isClickable)
        }
    }

    @Test
    fun `enabled single choice item is clickable`() {
        val choices = arrayOf(
            Choice(id = "item1", label = "Enabled choice"),
            Choice(id = "item2", enable = false, label = "Disabled choice")
        )

        val fragment = spy(newInstance(choices, "sessionId", "uid", false, SINGLE_CHOICE_DIALOG_TYPE))
        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        // test enabled item
        val enabledItemViewHolder =
            adapter.onCreateViewHolder(LinearLayout(testContext), adapter.getItemViewType(0)) as SingleViewHolder

        adapter.bindViewHolder(enabledItemViewHolder, 0)

        with(enabledItemViewHolder) {
            assertEquals(labelView.text, "Enabled choice")
            assertTrue(labelView.isEnabled)
            assertTrue(itemView.isClickable)
        }
    }

    @Test
    fun `disabled multiple choice item is not clickable`() {
        val choices = arrayOf(
            Choice(id = "item1", label = "Enabled choice"),
            Choice(id = "item2", enable = false, label = "Disabled choice")
        )

        val fragment =
            spy(newInstance(choices, "sessionId", "uid", false, MULTIPLE_CHOICE_DIALOG_TYPE))
        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        // test disabled item
        val disabledItemViewHolder =
            adapter.onCreateViewHolder(LinearLayout(testContext), adapter.getItemViewType(1))
                as MultipleViewHolder

        adapter.bindViewHolder(disabledItemViewHolder, 1)

        with(disabledItemViewHolder) {
            assertEquals(labelView.text, "Disabled choice")
            assertFalse(labelView.isEnabled)
            assertFalse(itemView.isClickable)
        }
    }

    @Test
    fun `enabled multiple choice item is clickable`() {
        val choices = arrayOf(
            Choice(id = "item1", label = "Enabled choice"),
            Choice(id = "item2", enable = false, label = "Disabled choice")
        )

        val fragment = spy(newInstance(choices, "sessionId", "uid", false, MULTIPLE_CHOICE_DIALOG_TYPE))
        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        // test enabled item
        val enabledItemViewHolder =
            adapter.onCreateViewHolder(LinearLayout(testContext), adapter.getItemViewType(0)) as MultipleViewHolder

        adapter.bindViewHolder(enabledItemViewHolder, 0)

        with(enabledItemViewHolder) {
            assertEquals(labelView.text, "Enabled choice")
            assertTrue(labelView.isEnabled)
            assertTrue(itemView.isClickable)
        }
    }

    @Test
    fun `disabled menu choice item is not clickable`() {
        val choices = arrayOf(
            Choice(id = "item1", label = "Enabled choice"),
            Choice(id = "item2", enable = false, label = "Disabled choice")
        )

        val fragment =
            spy(newInstance(choices, "sessionId", "uid", false, MENU_CHOICE_DIALOG_TYPE))
        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        // test disabled item
        val disabledItemViewHolder =
            adapter.onCreateViewHolder(LinearLayout(testContext), adapter.getItemViewType(1))
                as MenuViewHolder

        adapter.bindViewHolder(disabledItemViewHolder, 1)

        with(disabledItemViewHolder) {
            assertEquals(labelView.text, "Disabled choice")
            assertFalse(labelView.isEnabled)
            assertFalse(itemView.isClickable)
        }
    }

    @Test
    fun `enabled menu choice item is clickable`() {
        val choices = arrayOf(
            Choice(id = "item1", label = "Enabled choice"),
            Choice(id = "item2", enable = false, label = "Disabled choice")
        )

        val fragment = spy(newInstance(choices, "sessionId", "uid", false, MENU_CHOICE_DIALOG_TYPE))
        fragment.feature = mockFeature
        doReturn(appCompatContext).`when`(fragment).requireContext()
        doNothing().`when`(fragment).dismiss()

        val dialog = fragment.onCreateDialog(null)
        dialog.show()

        val adapter = dialog.findViewById<RecyclerView>(R.id.recyclerView).adapter as ChoiceAdapter

        // test enabled item
        val enabledItemViewHolder =
            adapter.onCreateViewHolder(LinearLayout(testContext), adapter.getItemViewType(0)) as MenuViewHolder

        adapter.bindViewHolder(enabledItemViewHolder, 0)

        with(enabledItemViewHolder) {
            assertEquals(labelView.text, "Enabled choice")
            assertTrue(labelView.isEnabled)
            assertTrue(itemView.isClickable)
        }
    }

    @Test
    fun `scroll to selected item`() {
        // array of 20 choices; 10th one is selected
        val choices = Array(20) { index ->
            if (index == 10) {
                item.copy(selected = true, label = "selected")
            } else {
                item.copy(label = "item$index")
            }
        }
        val fragment = newInstance(choices, "sessionId", "uid", true, SINGLE_CHOICE_DIALOG_TYPE)
        val inflater = LayoutInflater.from(testContext)
        val dialog = fragment.createDialogContentView(inflater)
        val recyclerView = dialog.findViewById<RecyclerView>(R.id.recyclerView)
        val layoutManager = recyclerView.layoutManager as LinearLayoutManager
        // these two lines are a bit of a hack to get the layout manager to draw the view.
        recyclerView.measure(0, 0)
        recyclerView.layout(0, 0, 100, 250)

        val selectedItemIndex = layoutManager.findLastCompletelyVisibleItemPosition()
        assertEquals(10, selectedItemIndex)
    }

    @Test
    fun `test toArrayOfChoices`() {
        val parcelables = Array<Parcelable>(1) { Choice(id = "id", label = "label") }
        val choice = parcelables.toArrayOfChoices()
        assertNotNull(choice)
    }

    private fun getAdapterFrom(fragment: ChoiceDialogFragment): ChoiceAdapter {
        val inflater = LayoutInflater.from(testContext)
        val view = fragment.createDialogContentView(inflater)
        val recyclerViewId = R.id.recyclerView

        return view.findViewById<RecyclerView>(recyclerViewId).adapter as ChoiceAdapter
    }
}
