package com.peachpasswords

import java.io.File
import javax.xml.parsers.DocumentBuilderFactory
import org.junit.Assert.assertEquals
import org.junit.Assert.assertTrue
import org.junit.Test
import org.w3c.dom.Element

class MainActivityManifestTest {
    @Test
    fun main_activity_declares_only_the_launcher_filter() {
        val manifest = manifestFile()
        val document = DocumentBuilderFactory.newInstance().apply {
            isNamespaceAware = true
        }.newDocumentBuilder().parse(manifest)
        val activities = document.getElementsByTagName("activity")
        val mainActivity = (0 until activities.length)
            .mapNotNull { activities.item(it) as? Element }
            .single { it.getAttributeNS(ANDROID_NAMESPACE, "name") == ".MainActivity" }

        val filters = mainActivity.getElementsByTagName("intent-filter")
        assertEquals("MainActivity must have only its launcher filter", 1, filters.length)
        val filter = filters.item(0) as Element
        val actions = filter.getElementsByTagName("action")
        val categories = filter.getElementsByTagName("category")
        assertEquals(1, actions.length)
        assertEquals(
            "android.intent.action.MAIN",
            (actions.item(0) as Element).getAttributeNS(ANDROID_NAMESPACE, "name"),
        )
        assertEquals(1, categories.length)
        assertEquals(
            "android.intent.category.LAUNCHER",
            (categories.item(0) as Element).getAttributeNS(ANDROID_NAMESPACE, "name"),
        )
        assertTrue(
            "MainActivity must not declare a custom peach URI handler",
            filter.getElementsByTagName("data").length == 0,
        )
    }

    private fun manifestFile(): File = File("src/main/AndroidManifest.xml")
        .takeIf { it.isFile }
        ?: File("app/src/main/AndroidManifest.xml")

    private companion object {
        const val ANDROID_NAMESPACE = "http://schemas.android.com/apk/res/android"
    }
}