show age for passwords in detail view (#339)

* show age for passwords in detail view

Implements #330.
This fetches the latest commit where the respective password file was
changed from the current HEAD and outputs the relative time since
the last change on the decrypt page.

* Move lastChanged logic out of PgpActivity

This nicely encapsulates the lastChanged logic (and thus separates it
from dependencies like git). The last changed date is now passed as a
timestamp using the Intent's extra info.

2 files changed, 53 insertions, 0 deletions

diff --git a/app/src/main/java/com/zeapo/pwdstore/PasswordStore.java b/app/src/main/java/com/zeapo/pwdstore/PasswordStore.java
index acfadf99..99593700 100644
--- a/app/src/main/java/com/zeapo/pwdstore/PasswordStore.java
+++ b/app/src/main/java/com/zeapo/pwdstore/PasswordStore.java
@@ -42,7 +42,9 @@ import com.zeapo.pwdstore.utils.PasswordRepository;
 
 import org.apache.commons.io.FileUtils;
 import org.eclipse.jgit.api.Git;
+import org.eclipse.jgit.api.errors.GitAPIException;
 import org.eclipse.jgit.lib.Repository;
+import org.eclipse.jgit.revwalk.RevCommit;
 
 import java.io.File;
 import java.util.ArrayList;
@@ -406,11 +408,40 @@ public class PasswordStore extends AppCompatActivity {
         }
     }
 
+    private String getRelativePath(String fullPath, String repositoryPath) {
+        return fullPath.replace(repositoryPath, "").replaceAll("/+", "/");
+    }
+
+    public int getLastChangedTimestamp(String fullPath) {
+        File repoPath = PasswordRepository.getRepositoryDirectory(this);
+        Repository repository = PasswordRepository.getRepository(repoPath);
+
+        if (repository == null) {
+            return -1;
+        }
+
+        Git git = new Git(repository);
+        String relativePath = getRelativePath(fullPath, repoPath.getAbsolutePath()).substring(1);
+        Iterable<RevCommit> iterable;
+
+        try {
+            iterable = git.log().addPath(relativePath).call();
+        } catch (GitAPIException e) {
+            System.out.println("Exception caught :(");
+            e.printStackTrace();
+            return -1;
+        }
+
+        RevCommit latestCommit = iterable.iterator().next();
+        return latestCommit.getCommitTime();
+    }
+
     public void decryptPassword(PasswordItem item) {
         Intent intent = new Intent(this, PgpActivity.class);
         intent.putExtra("NAME", item.toString());
         intent.putExtra("FILE_PATH", item.getFile().getAbsolutePath());
         intent.putExtra("REPO_PATH", PasswordRepository.getRepositoryDirectory(getApplicationContext()).getAbsolutePath());
+        intent.putExtra("LAST_CHANGED_TIMESTAMP", getLastChangedTimestamp(item.getFile().getAbsolutePath()));
         intent.putExtra("OPERATION", "DECRYPT");
 
         // Adds shortcut
diff --git a/app/src/main/java/com/zeapo/pwdstore/crypto/PgpActivity.kt b/app/src/main/java/com/zeapo/pwdstore/crypto/PgpActivity.kt
index 19b71b72..1a8a5051 100644
--- a/app/src/main/java/com/zeapo/pwdstore/crypto/PgpActivity.kt
+++ b/app/src/main/java/com/zeapo/pwdstore/crypto/PgpActivity.kt
@@ -12,6 +12,7 @@ import android.os.SystemClock
 import android.preference.PreferenceManager
 import android.support.v7.app.AppCompatActivity
 import android.text.TextUtils
+import android.text.format.DateUtils
 import android.text.method.PasswordTransformationMethod
 import android.util.Log
 import android.view.*
@@ -20,6 +21,7 @@ import com.zeapo.pwdstore.PasswordEntry
 import com.zeapo.pwdstore.R
 import com.zeapo.pwdstore.UserPreference
 import com.zeapo.pwdstore.pwgenDialogFragment
+import com.zeapo.pwdstore.utils.PasswordRepository
 import com.zeapo.pwdstore.utils.Totp
 import kotlinx.android.synthetic.main.decrypt_layout.*
 import kotlinx.android.synthetic.main.encrypt_layout.*
@@ -47,6 +49,7 @@ class PgpActivity : AppCompatActivity(), OpenPgpServiceConnection.OnBound {
 
     private val fullPath: String by lazy { intent.getStringExtra("FILE_PATH") }
     private val name: String by lazy { getName(fullPath, repoPath) }
+    private val lastChangedString: CharSequence by lazy { getLastChangedString(intent.getIntExtra("LAST_CHANGED_TIMESTAMP", -1)) }
     private val relativeParentPath: String by lazy { getParentPath(fullPath, repoPath) }
 
     private val settings: SharedPreferences by lazy { PreferenceManager.getDefaultSharedPreferences(this) }
@@ -76,6 +79,13 @@ class PgpActivity : AppCompatActivity(), OpenPgpServiceConnection.OnBound {
                 setContentView(R.layout.decrypt_layout)
                 crypto_password_category_decrypt.text = relativeParentPath
                 crypto_password_file.text = name
+
+                crypto_password_last_changed.text = try {
+                    this.resources.getString(R.string.last_changed, lastChangedString)
+                } catch (e: RuntimeException) {
+                    showToast(getString(R.string.get_last_changed_failed))
+                    ""
+                }
             }
             "ENCRYPT" -> {
                 setContentView(R.layout.encrypt_layout)
@@ -514,6 +524,18 @@ class PgpActivity : AppCompatActivity(), OpenPgpServiceConnection.OnBound {
         delayTask?.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR)
     }
 
+    /**
+     * Gets a relative string describing when this shape was last changed
+     * (e.g. "one hour ago")
+     */
+    private fun getLastChangedString(timeStamp: Int): CharSequence {
+        if (timeStamp < 0) {
+            throw RuntimeException()
+        }
+
+        return DateUtils.getRelativeTimeSpanString(this, timeStamp.toLong() * 1000, true)
+    }
+
     @SuppressLint("StaticFieldLeak")
     inner class DelayShow(val activity: PgpActivity) : AsyncTask<Void, Int, Boolean>() {
         private val pb: ProgressBar by lazy { pbLoading }