Add support for shorthand SDK for bounding check

- fixes #1630

brut.apktool/apktool-lib/src/main/java/brut/androlib/Androlib.java

@@ -287,7 +287,7 @@ public class Androlib {
 
         if (meta.sdkInfo != null && meta.sdkInfo.get("minSdkVersion") != null) {
             String minSdkVersion = meta.sdkInfo.get("minSdkVersion");
-            mMinSdkVersion = getMinSdkVersionFromAndroidCodename(meta, minSdkVersion);
+            mMinSdkVersion = mAndRes.getMinSdkVersionFromAndroidCodename(meta, minSdkVersion);
         }
 
         if (outFile == null) {
@@ -728,19 +728,6 @@ public class Androlib {
         return files;
     }
 
-    private int getMinSdkVersionFromAndroidCodename(MetaInfo meta, String sdkVersion) {
-        switch (sdkVersion) {
-            case "M":
-                return ResConfigFlags.SDK_MNC;
-            case "N":
-                return ResConfigFlags.SDK_NOUGAT;
-            case "O":
-                return ResConfigFlags.SDK_OREO;
-            default:
-                return Integer.parseInt(meta.sdkInfo.get("minSdkVersion"));
-        }
-    }
-
     private boolean isModified(File working, File stored) {
         return ! stored.exists() || BrutIO.recursiveModifiedTime(working) > BrutIO .recursiveModifiedTime(stored);
     }

brut.apktool/apktool-lib/src/main/java/brut/androlib/res/AndrolibResources.java

@@ -19,6 +19,7 @@ package brut.androlib.res;
 import brut.androlib.AndrolibException;
 import brut.androlib.ApkOptions;
 import brut.androlib.err.CantFindFrameworkResException;
+import brut.androlib.meta.MetaInfo;
 import brut.androlib.meta.PackageInfo;
 import brut.androlib.meta.VersionInfo;
 import brut.androlib.res.data.*;
@@ -308,9 +309,10 @@ final public class AndrolibResources {
     }
 
     public String checkTargetSdkVersionBounds() {
-        int target = Integer.parseInt(mTargetSdkVersion);
+        int target = mapSdkShorthandToVersion(mTargetSdkVersion);
-        int min = (mMinSdkVersion != null) ? Integer.parseInt(mMinSdkVersion) : 0;
+
-        int max = (mMaxSdkVersion != null) ? Integer.parseInt(mMaxSdkVersion) : target;
+        int min = (mMinSdkVersion != null) ? mapSdkShorthandToVersion(mMinSdkVersion) : 0;
+        int max = (mMaxSdkVersion != null) ? mapSdkShorthandToVersion(mMaxSdkVersion) : target;
 
         target = Math.min(max, target);
         target = Math.max(min, target);
@@ -455,6 +457,28 @@ final public class AndrolibResources {
         }
     }
 
+    public int getMinSdkVersionFromAndroidCodename(MetaInfo meta, String sdkVersion) {
+        int sdkNumber = mapSdkShorthandToVersion(sdkVersion);
+
+        if (sdkNumber == ResConfigFlags.SDK_BASE) {
+            return Integer.parseInt(meta.sdkInfo.get("minSdkVersion"));
+        }
+        return sdkNumber;
+    }
+
+    private int mapSdkShorthandToVersion(String sdkVersion) {
+        switch (sdkVersion) {
+            case "M":
+                return ResConfigFlags.SDK_MNC;
+            case "N":
+                return ResConfigFlags.SDK_NOUGAT;
+            case "O":
+                return ResConfigFlags.SDK_OREO;
+            default:
+                return Integer.parseInt(sdkVersion);
+        }
+    }
+
     public boolean detectWhetherAppIsFramework(File appDir)
             throws AndrolibException {
         File publicXml = new File(appDir, "res/values/public.xml");

brut.apktool/apktool-lib/src/test/java/brut/androlib/InvalidSdkBoundingTest.java

@@ -75,4 +75,16 @@ public class InvalidSdkBoundingTest {
         androlibResources.setSdkInfo(sdkInfo);
         assertEquals("25", androlibResources.checkTargetSdkVersionBounds());
     }
+
+
+    @Test
+    public void checkForShortHandSdkTag() throws BrutException, IOException {
+        AndrolibResources androlibResources = new AndrolibResources();
+
+        Map<String, String> sdkInfo = new LinkedHashMap<>();
+        sdkInfo.put("targetSdkVersion", "O");
+
+        androlibResources.setSdkInfo(sdkInfo);
+        assertEquals("26", androlibResources.checkTargetSdkVersionBounds());
+    }
 }