claude added export functionality, 2 iterations

app/src/main/AndroidManifest.xml

@@ -5,6 +5,9 @@
     <!-- Needed on API 26–28 to read files from Downloads via file picker -->
     <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"
         android:maxSdkVersion="28" />
+    <!-- Needed on API 26–28 to write files via ACTION_CREATE_DOCUMENT -->
+    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"
+        android:maxSdkVersion="28" />
 
     <application
         android:name=".VoCoachApp"

app/src/main/java/dev/lueckemeyer/vocoach/MainActivity.java

@@ -4,10 +4,8 @@ import android.app.AlertDialog;
 import android.content.Intent;
 import android.net.Uri;
 import android.os.Bundle;
-import android.os.Environment;
 import android.view.Menu;
 import android.view.MenuItem;
-import android.view.View;
 import android.widget.ProgressBar;
 import android.widget.Toast;
 
@@ -19,10 +17,14 @@ import androidx.navigation.fragment.NavHostFragment;
 import androidx.navigation.ui.AppBarConfiguration;
 import androidx.navigation.ui.NavigationUI;
 
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.Locale;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 
 import dev.lueckemeyer.vocoach.databinding.ActivityMainBinding;
+import dev.lueckemeyer.vocoach.importer.CsvExporter;
 import dev.lueckemeyer.vocoach.importer.CsvImporter;
 
 public class MainActivity extends AppCompatActivity {
@@ -30,7 +32,7 @@ public class MainActivity extends AppCompatActivity {
     private ActivityMainBinding binding;
     private final ExecutorService exec = Executors.newSingleThreadExecutor();
 
-    // ── File picker launcher ──────────────────────────────────────────────────
+    // ── File picker (import) ──────────────────────────────────────────────────
     private final ActivityResultLauncher<Intent> filePickerLauncher =
             registerForActivityResult(
                     new ActivityResultContracts.StartActivityForResult(),
@@ -41,6 +43,17 @@ public class MainActivity extends AppCompatActivity {
                         }
                     });
 
+    // ── File creator (export) ─────────────────────────────────────────────────
+    private final ActivityResultLauncher<Intent> fileCreateLauncher =
+            registerForActivityResult(
+                    new ActivityResultContracts.StartActivityForResult(),
+                    result -> {
+                        if (result.getResultCode() == RESULT_OK && result.getData() != null) {
+                            Uri uri = result.getData().getData();
+                            if (uri != null) startExport(uri);
+                        }
+                    });
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -68,68 +81,106 @@ public class MainActivity extends AppCompatActivity {
 
     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
-        if (item.getItemId() == R.id.action_add_vocabulary) {
+        int id = item.getItemId();
+        if (id == R.id.action_add_vocabulary) {
             openFilePicker();
             return true;
+        } else if (id == R.id.action_save_data) {
+            openFileSaver();
+            return true;
         }
         return super.onOptionsItemSelected(item);
     }
 
-    // ── File picker ───────────────────────────────────────────────────────────
+    // ── Import ────────────────────────────────────────────────────────────────
 
     private void openFilePicker() {
         Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
         intent.addCategory(Intent.CATEGORY_OPENABLE);
-        intent.setType("*/*");                          // text/csv not always recognised
+        intent.setType("*/*");
         intent.putExtra(Intent.EXTRA_MIME_TYPES,
                 new String[]{"text/csv", "text/comma-separated-values", "text/plain"});
+        filePickerLauncher.launch(intent);
+    }
 
-        // Pre-select the Downloads folder
-        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
-            Uri downloadsUri = android.provider.DocumentsContract.buildRootUri(
-                    "com.android.externalstorage.documents", "primary");
-            intent.putExtra(android.provider.DocumentsContract.EXTRA_INITIAL_URI, downloadsUri);
+    private void startImport(Uri uri) {
+        ProgressBar pb = new ProgressBar(this);
+        pb.setPadding(64, 64, 64, 64);
+        AlertDialog dialog = new AlertDialog.Builder(this)
+                .setTitle("Importing vocabulary…")
+                .setView(pb)
+                .setCancelable(false)
+                .create();
+        dialog.show();
+
+        exec.execute(() -> {
+            CsvImporter.Result result = new CsvImporter(this).importFromUri(uri);
+            runOnUiThread(() -> {
+                dialog.dismiss();
+                showImportResult(result);
+            });
+        });
     }
 
-        filePickerLauncher.launch(intent);
+    private void showImportResult(CsvImporter.Result r) {
+        if (r.errorMessage != null) {
+            new AlertDialog.Builder(this)
+                    .setTitle("Import failed")
+                    .setMessage(r.errorMessage)
+                    .setPositiveButton("OK", null)
+                    .show();
+        } else {
+            String msg = r.cardsInserted + " word(s) imported";
+            if (r.triesRestored > 0) msg += ", " + r.triesRestored + " try record(s) restored";
+            if (r.rowsSkipped  > 0) msg += "\n" + r.rowsSkipped + " row(s) skipped";
+            msg += ".";
+            Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
+        }
     }
 
-    // ── Import ────────────────────────────────────────────────────────────────
+    // ── Export ────────────────────────────────────────────────────────────────
 
-    private void startImport(Uri uri) {
-        // Show a non-cancelable progress dialog while importing
-        ProgressBar progressBar = new ProgressBar(this);
-        progressBar.setPadding(64, 64, 64, 64);
+    private void openFileSaver() {
+        String timestamp = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.US)
+                .format(new Date());
+        String filename  = "vocoach_" + timestamp + ".csv";
 
-        AlertDialog progressDialog = new AlertDialog.Builder(this)
-                .setTitle("Importing vocabulary…")
-                .setView(progressBar)
+        Intent intent = new Intent(Intent.ACTION_CREATE_DOCUMENT);
+        intent.addCategory(Intent.CATEGORY_OPENABLE);
+        intent.setType("text/csv");
+        intent.putExtra(Intent.EXTRA_TITLE, filename);
+        fileCreateLauncher.launch(intent);
+    }
+
+    private void startExport(Uri uri) {
+        ProgressBar pb = new ProgressBar(this);
+        pb.setPadding(64, 64, 64, 64);
+        AlertDialog dialog = new AlertDialog.Builder(this)
+                .setTitle("Saving data…")
+                .setView(pb)
                 .setCancelable(false)
                 .create();
-        progressDialog.show();
-
-        CsvImporter importer = new CsvImporter(this);
+        dialog.show();
 
         exec.execute(() -> {
-            CsvImporter.Result result = importer.importFromUri(uri);
+            CsvExporter.Result result = new CsvExporter(this).exportToUri(uri);
             runOnUiThread(() -> {
-                progressDialog.dismiss();
-                showResult(result);
+                dialog.dismiss();
+                showExportResult(result);
             });
         });
     }
 
-    private void showResult(CsvImporter.Result result) {
-        if (result.errorMessage != null) {
+    private void showExportResult(CsvExporter.Result r) {
+        if (r.errorMessage != null) {
             new AlertDialog.Builder(this)
-                    .setTitle("Import failed")
-                    .setMessage(result.errorMessage)
+                    .setTitle("Save failed")
+                    .setMessage(r.errorMessage)
                     .setPositiveButton("OK", null)
                     .show();
         } else {
-            String msg = result.cardsInserted + " word(s) imported.";
-            if (result.rowsSkipped > 0)
-                msg += "\n" + result.rowsSkipped + " row(s) skipped due to errors.";
+            String msg = r.cardsExported + " word(s) and " +
+                         r.triesExported + " try record(s) saved.";
             Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
         }
     }

app/src/main/java/dev/lueckemeyer/vocoach/db/dao/LeitnerStateDao.java

@@ -12,6 +12,16 @@ public interface LeitnerStateDao {
     @Insert long insert(LeitnerState state);
     @Update void update(LeitnerState state);
 
+    @Query("SELECT * FROM leitner_state ORDER BY card_id ASC")
+    List<LeitnerState> getAllSync();
+
+    /** Used during extended CSV import to locate a leitner_state by card identity + direction. */
+    @Query("SELECT ls.* FROM leitner_state ls " +
+           "JOIN card c ON c.id = ls.card_id " +
+           "WHERE c.french = :french AND c.native_lang = :nativeLang " +
+           "AND ls.direction = :direction LIMIT 1")
+    LeitnerState getByFrenchNativeDirectionSync(String french, String nativeLang, String direction);
+
     @Query("SELECT * FROM leitner_state WHERE id = :id LIMIT 1")
     LeitnerState getByIdSync(int id);
 

app/src/main/java/dev/lueckemeyer/vocoach/db/dao/TryDao.java

@@ -13,6 +13,10 @@ public interface TryDao {
     @Query("SELECT * FROM try_record WHERE leitner_state_id = :stateId ORDER BY responded_at ASC")
     List<TryRecord> getForStateSync(int stateId);
 
+    /** All try records ordered by time — used during full export. */
+    @Query("SELECT * FROM try_record ORDER BY responded_at ASC")
+    List<TryRecord> getAllSync();
+
     /** Returns leitner_state_ids attempted today (epoch seconds window). */
     @Query("SELECT DISTINCT leitner_state_id FROM try_record " +
            "WHERE direction = :direction AND responded_at >= :dayStart")

app/src/main/java/dev/lueckemeyer/vocoach/importer/CsvExporter.java

+package dev.lueckemeyer.vocoach.importer;
+
+import android.content.Context;
+import android.net.Uri;
+
+import java.io.*;
+import java.nio.charset.StandardCharsets;
+import java.util.*;
+
+import dev.lueckemeyer.vocoach.db.VocabDatabase;
+import dev.lueckemeyer.vocoach.db.entity.*;
+
+/**
+ * Exports the full database to a CSV file that can be re-imported by
+ * CsvImporter (which ignores the extra columns) or by the standalone
+ * command-line importer.
+ *
+ * Format
+ * ──────
+ * The file has two sections separated by a blank line:
+ *
+ * Section 1 — CARD rows (row_type = "card")
+ *   All 26 standard import columns  +  leitner_box_fr  +  leitner_box_native
+ *
+ * Section 2 — TRY rows (row_type = "try")
+ *   card_french, card_native_lang, leitner_state_id,
+ *   direction, correct (true/false), responded_at (epoch seconds)
+ *
+ * The standard importer ignores columns beyond column 25 and ignores any
+ * rows whose word_type it does not recognise, so "card" and "try" in column 0
+ * cause those rows to be silently skipped on a plain re-import — only the
+ * card data (columns 1-25) is used.  The app's own CsvImporter additionally
+ * processes the extra columns to restore Leitner state and try history.
+ */
+public class CsvExporter {
+
+    // ── Result ────────────────────────────────────────────────────────────────
+    public static class Result {
+        public final int    cardsExported;
+        public final int    triesExported;
+        public final String errorMessage; // null = success
+
+        Result(int cards, int tries, String error) {
+            cardsExported = cards;
+            triesExported = tries;
+            errorMessage  = error;
+        }
+    }
+
+    private final VocabDatabase db;
+    private final Context       context;
+
+    public CsvExporter(Context context) {
+        this.context = context.getApplicationContext();
+        this.db      = VocabDatabase.getInstance(this.context);
+    }
+
+    // ── Public entry point ────────────────────────────────────────────────────
+
+    /** Call from a background thread. Writes the CSV to the given URI. */
+    public Result exportToUri(Uri uri) {
+        try (OutputStream os = context.getContentResolver().openOutputStream(uri, "wt");
+             BufferedWriter w = new BufferedWriter(
+                     new OutputStreamWriter(os, StandardCharsets.UTF_8))) {
+
+            // ── Build lookup maps ─────────────────────────────────────────────
+            // book id → Book
+            Map<Integer, Book> books = new HashMap<>();
+            for (Book b : db.bookDao().getAllSync()) books.put(b.id, b);
+
+            // unit id → Unit
+            Map<Integer, Unit> units = new HashMap<>();
+            for (Book b : books.values())
+                for (Unit u : db.unitDao().getByBookSync(b.id)) units.put(u.id, u);
+
+            // volet id → Volet
+            Map<Integer, Volet> volets = new HashMap<>();
+            for (Volet v : db.voletDao().getAllSync()) volets.put(v.id, v);
+
+            // card id → Card
+            Map<Integer, Card> cards = new HashMap<>();
+            for (Volet v : volets.values())
+                for (Card c : db.cardDao().getByVoletSync(v.id)) cards.put(c.id, c);
+
+            // card id → LeitnerState per direction
+            Map<Integer, LeitnerState> lsFr  = new HashMap<>(); // fr_to_native
+            Map<Integer, LeitnerState> lsNat = new HashMap<>(); // native_to_fr
+            for (LeitnerState ls : db.leitnerStateDao().getAllSync()) {
+                if ("fr_to_native".equals(ls.direction)) lsFr.put(ls.cardId, ls);
+                else                                     lsNat.put(ls.cardId, ls);
+            }
+
+            // leitner_state id → card id (for try export)
+            Map<Integer, Integer> lsIdToCardId = new HashMap<>();
+            for (LeitnerState ls : db.leitnerStateDao().getAllSync())
+                lsIdToCardId.put(ls.id, ls.cardId);
+
+            // ── Section 1: card rows ──────────────────────────────────────────
+            w.write(cardHeader());
+            w.newLine();
+
+            // Order: book asc, unit position asc, volet position asc, card id asc
+            List<Card> orderedCards = orderedCards(books, units, volets, cards);
+            int cardCount = 0;
+
+            for (Card card : orderedCards) {
+                Volet  volet = volets.get(card.voletId);
+                Unit   unit  = units.get(volet.unitId);
+                Book   book  = books.get(unit.bookId);
+
+                NounDetail      nd = db.detailDao().getNounSync(card.id);
+                VerbDetail      vd = db.detailDao().getVerbSync(card.id);
+                AdjectiveDetail ad = db.detailDao().getAdjectiveSync(card.id);
+                AdverbDetail    rd = db.detailDao().getAdverbSync(card.id);
+
+                LeitnerState lsFrState  = lsFr.getOrDefault(card.id,  null);
+                LeitnerState lsNatState = lsNat.getOrDefault(card.id, null);
+                int boxFr  = lsFrState  != null ? lsFrState.boxNumber  : 1;
+                int boxNat = lsNatState != null ? lsNatState.boxNumber : 1;
+
+                w.write(cardRow(card, book, unit, volet, nd, vd, ad, rd, boxFr, boxNat));
+                w.newLine();
+                cardCount++;
+            }
+
+            // ── Section 2: try rows ───────────────────────────────────────────
+            w.newLine();
+            w.write(tryHeader());
+            w.newLine();
+
+            List<TryRecord> tries = db.tryDao().getAllSync();
+            int tryCount = 0;
+
+            for (TryRecord tr : tries) {
+                Integer cardId = lsIdToCardId.get(tr.leitnerStateId);
+                if (cardId == null) continue;
+                Card card = cards.get(cardId);
+                if (card == null) continue;
+                w.write(tryRow(card, tr));
+                w.newLine();
+                tryCount++;
+            }
+
+            w.flush();
+            return new Result(cardCount, tryCount, null);
+
+        } catch (Exception e) {
+            return new Result(0, 0, "Export failed: " + e.getMessage());
+        }
+    }
+
+    // ── CSV headers ───────────────────────────────────────────────────────────
+
+    private static String cardHeader() {
+        return "row_type,word_type,french,native_lang,phonetic,example_sentence,notes," +
+               "book_title,book_description,unit_position,unit_title," +
+               "volet_position,volet_title," +
+               "gender,plural_form,is_proper," +
+               "infinitive,verb_group,participe_passe,participe_present," +
+               "auxiliary,is_reflexive,is_irregular," +
+               "feminine_form,plural_form_adj,feminine_plural_form,derived_from," +
+               "leitner_box_fr,leitner_box_native";
+    }
+
+    private static String tryHeader() {
+        return "row_type,card_french,card_native_lang," +
+               "leitner_state_id,direction,correct,responded_at";
+    }
+
+    // ── Row builders ──────────────────────────────────────────────────────────
+
+    private static String cardRow(Card card, Book book, Unit unit, Volet volet,
+                                  NounDetail nd, VerbDetail vd,
+                                  AdjectiveDetail ad, AdverbDetail rd,
+                                  int boxFr, int boxNat) {
+        return csv(
+                "card",
+                s(card.wordType),
+                s(card.french),
+                s(card.nativeLang),
+                s(card.phonetic),
+                s(card.exampleSentence),
+                s(card.notes),
+                s(book.title),
+                s(book.description),
+                String.valueOf(unit.position),
+                s(unit.title),
+                String.valueOf(volet.position),
+                s(volet.title),
+                // noun
+                nd != null ? s(nd.gender)     : "",
+                nd != null ? s(nd.pluralForm)  : "",
+                nd != null ? b(nd.isProper)    : "",
+                // verb
+                vd != null ? s(vd.infinitive)       : "",
+                vd != null ? s(vd.verbGroup)         : "",
+                vd != null ? s(vd.participePasse)    : "",
+                vd != null ? s(vd.participePresent)  : "",
+                vd != null ? s(vd.auxiliary)         : "",
+                vd != null ? b(vd.isReflexive)       : "",
+                vd != null ? b(vd.isIrregular)       : "",
+                // adjective
+                ad != null ? s(ad.feminineForm)       : "",
+                ad != null ? s(ad.pluralForm)          : "",
+                ad != null ? s(ad.femininePluralForm)  : "",
+                // adverb
+                rd != null ? s(rd.derivedFrom) : "",
+                // leitner state
+                String.valueOf(boxFr),
+                String.valueOf(boxNat)
+        );
+    }
+
+    private static String tryRow(Card card, TryRecord tr) {
+        return csv(
+                "try",
+                s(card.french),
+                s(card.nativeLang),
+                String.valueOf(tr.leitnerStateId),
+                s(tr.direction),
+                b(tr.correct),
+                String.valueOf(tr.respondedAt)
+        );
+    }
+
+    // ── Helpers ───────────────────────────────────────────────────────────────
+
+    /** Null-safe string — empty string if null. */
+    private static String s(String v) { return v != null ? v : ""; }
+
+    /** Boolean to "true"/"false". */
+    private static String b(boolean v) { return v ? "true" : "false"; }
+
+    /**
+     * Joins fields as a CSV line.  Fields containing commas, quotes or
+     * newlines are wrapped in double-quotes; internal double-quotes are escaped
+     * by doubling them.
+     */
+    private static String csv(String... fields) {
+        StringBuilder sb = new StringBuilder();
+        for (int i = 0; i < fields.length; i++) {
+            if (i > 0) sb.append(',');
+            String f = fields[i];
+            if (f.contains(",") || f.contains("\"") || f.contains("\n")) {
+                sb.append('"').append(f.replace("\"", "\"\"")).append('"');
+            } else {
+                sb.append(f);
+            }
+        }
+        return sb.toString();
+    }
+
+    /** Returns cards ordered by book id, unit position, volet position, card id. */
+    private static List<Card> orderedCards(Map<Integer, Book>  books,
+                                           Map<Integer, Unit>  units,
+                                           Map<Integer, Volet> volets,
+                                           Map<Integer, Card>  cards) {
+        List<Card> list = new ArrayList<>(cards.values());
+        list.sort((a, b) -> {
+            Volet va = volets.get(a.voletId), vb = volets.get(b.voletId);
+            Unit  ua = units.get(va.unitId),  ub = units.get(vb.unitId);
+            Book  ba = books.get(ua.bookId),  bb = books.get(ub.bookId);
+            if (ba.id != bb.id)        return Integer.compare(ba.id, bb.id);
+            if (ua.position != ub.position) return Integer.compare(ua.position, ub.position);
+            if (va.position != vb.position) return Integer.compare(va.position, vb.position);
+            return Integer.compare(a.id, b.id);
+        });
+        return list;
+    }
+}

app/src/main/res/menu/menu_main.xml

@@ -8,4 +8,10 @@
         android:icon="@android:drawable/ic_menu_add"
         app:showAsAction="never"/>
 
+    <item
+        android:id="@+id/action_save_data"
+        android:title="@string/action_save_data"
+        android:icon="@android:drawable/ic_menu_save"
+        app:showAsAction="never"/>
+
 </menu>

app/src/main/res/values/strings.xml

@@ -2,4 +2,5 @@
 <resources>
     <string name="app_name">VoCoach</string>
     <string name="action_add_vocabulary">Add vocabulary</string>
+    <string name="action_save_data">Save data</string>
 </resources>