app installer: get basic apk info

app/src/main/java/com/github/fishb1/apkinfo/ApkInfo.kt

@@ -0,0 +1,52 @@
+/*
+ *  Copyright (C) 2022 fishbone
+ *
+ *  This code is licensed under MIT license (see LICENSE file for details)
+ */
+
+package com.github.fishb1.apkinfo
+
+import com.android.apksig.internal.apk.AndroidBinXmlParser
+import com.android.apksig.internal.apk.AndroidBinXmlParser.XmlParserException
+import java.io.InputStream
+import java.nio.ByteBuffer
+import java.util.zip.ZipEntry
+import java.util.zip.ZipInputStream
+
+data class ApkInfo(
+    val compileSdkVersion: Int = 0,
+    val compileSdkVersionCodename: String = "",
+    val installLocation: String = "",
+    val packageName: String = "",
+    val platformBuildVersionCode: Int = 0,
+    val platformBuildVersionName: String = "",
+    val versionCode: Int = 0,
+    val versionName: String = "",
+) {
+
+    companion object {
+
+        private val EMPTY = ApkInfo()
+
+        private const val MANIFEST_FILE_NAME = "AndroidManifest.xml"
+
+        fun fromInputStream(stream: InputStream): ApkInfo {
+            ZipInputStream(stream).use { zip ->
+                var entry: ZipEntry?
+                do {
+                    entry = zip.nextEntry
+                    if (entry?.name == MANIFEST_FILE_NAME) {
+                        val data = ByteBuffer.wrap(zip.readBytes())
+                        return try {
+                            val parser = AndroidBinXmlParser(data)
+                            ManifestUtils.readApkInfo(parser)
+                        } catch (e: XmlParserException) {
+                            EMPTY
+                        }
+                    }
+                } while (entry != null)
+            }
+            return EMPTY
+        }
+    }
+}

app/src/main/java/com/github/fishb1/apkinfo/ApkInfoBuilder.kt

@@ -0,0 +1,64 @@
+/*
+ *  Copyright (C) 2022 fishbone
+ *
+ *  This code is licensed under MIT license (see LICENSE file for details)
+ */
+
+package com.github.fishb1.apkinfo
+
+internal class ApkInfoBuilder {
+
+    private var compileSdkVersion: Int = 0
+    private var compileSdkVersionCodename: String = ""
+    private var installLocation: String = ""
+    private var packageName: String = ""
+    private var platformBuildVersionCode: Int = 0
+    private var platformBuildVersionName: String = ""
+    private var versionCode: Int = 0
+    private var versionName: String = ""
+
+    fun compileSdkVersion(value: Int) = apply {
+        compileSdkVersion = value
+    }
+
+    fun compileSdkVersionCodename(value: String) = apply {
+        compileSdkVersionCodename = value
+    }
+
+    fun installLocation(value: String) = apply {
+        installLocation = value
+    }
+
+    fun packageName(value: String) = apply {
+        packageName = value
+    }
+
+    fun platformBuildVersionCode(value: Int) = apply {
+        platformBuildVersionCode = value
+    }
+
+    fun platformBuildVersionName(value: String) = apply {
+        platformBuildVersionName = value
+    }
+
+    fun versionCode(value: Int) = apply {
+        versionCode = value
+    }
+
+    fun versionName(value: String) = apply {
+        versionName = value
+    }
+
+    fun build(): ApkInfo {
+        return ApkInfo(
+            compileSdkVersion = compileSdkVersion,
+            compileSdkVersionCodename =compileSdkVersionCodename,
+            installLocation = installLocation,
+            packageName = packageName,
+            platformBuildVersionCode = platformBuildVersionCode,
+            platformBuildVersionName = platformBuildVersionName,
+            versionCode = versionCode,
+            versionName = versionName,
+        )
+    }
+}

app/src/main/java/com/github/fishb1/apkinfo/ManifestUtils.kt

@@ -0,0 +1,55 @@
+/*
+ *  Copyright (C) 2022 fishbone
+ *
+ *  This code is licensed under MIT license (see LICENSE file for details)
+ */
+
+package com.github.fishb1.apkinfo
+
+import com.android.apksig.internal.apk.AndroidBinXmlParser
+
+internal object ManifestUtils {
+
+    private const val TAG_MANIFEST = "manifest"
+
+    private const val ATTR_COMPILE_SDK_VERSION = "compileSdkVersion"
+    private const val ATTR_COMPILE_SDK_VERSION_CODENAME = "compileSdkVersionCodename"
+    private const val ATTR_INSTALL_LOCATION = "installLocation"
+    private const val ATTR_PACKAGE = "package"
+    private const val ATTR_PLATFORM_BUILD_VERSION_CODE = "platformBuildVersionCode"
+    private const val ATTR_PLATFORM_BUILD_VERSION_NAME = "platformBuildVersionName"
+    private const val ATTR_VERSION_CODE = "versionCode"
+    private const val ATTR_VERSION_NAME = "versionName"
+
+    fun readApkInfo(parser: AndroidBinXmlParser): ApkInfo {
+        val builder = ApkInfoBuilder()
+        var eventType = parser.eventType
+        while (eventType != AndroidBinXmlParser.EVENT_END_DOCUMENT) {
+            if (eventType == AndroidBinXmlParser.EVENT_START_ELEMENT && parser.name == TAG_MANIFEST) {
+
+                for (i in 0 until parser.attributeCount) {
+                    when (parser.getAttributeName(i)) {
+                        ATTR_COMPILE_SDK_VERSION ->
+                            builder.compileSdkVersion(parser.getAttributeIntValue(i))
+                        ATTR_COMPILE_SDK_VERSION_CODENAME ->
+                            builder.compileSdkVersionCodename(parser.getAttributeStringValue(i))
+                        ATTR_INSTALL_LOCATION ->
+                            builder.installLocation(parser.getAttributeStringValue(i))
+                        ATTR_PACKAGE ->
+                            builder.packageName(parser.getAttributeStringValue(i))
+                        ATTR_PLATFORM_BUILD_VERSION_CODE ->
+                            builder.platformBuildVersionCode(parser.getAttributeIntValue(i))
+                        ATTR_PLATFORM_BUILD_VERSION_NAME ->
+                            builder.platformBuildVersionName(parser.getAttributeStringValue(i))
+                        ATTR_VERSION_CODE ->
+                            builder.versionCode(parser.getAttributeIntValue(i))
+                        ATTR_VERSION_NAME ->
+                            builder.versionName(parser.getAttributeStringValue(i))
+                    }
+                }
+            }
+            eventType = parser.next()
+        }
+        return builder.build()
+    }
+}