Add site login and alternate-source search for paywalled articles

Deliberately not a paywall-bypass mechanism -- that space (archive.today-style
proxies, "Bypass Paywalls" extensions) is legally grey, adversarial toward
publishers, and constantly breaking. Instead:

- BrowserScreen: a real interactive mini-browser (JS + DOM storage on,
  ordinary navigation, no Readability interception) for the two cases where
  the user needs to actually USE a page rather than read it. Reached from
  a new overflow menu on the article reader:
  - "Log in to this site" opens the article's own URL there so the user can
    sign into a site they already subscribe to. Needs no extra plumbing:
    Android's CookieManager is one process-wide store shared by every WebView
    in the app, so a session cookie set here is picked up automatically by
    the reader's (JS-off) extraction WebView on the next visit to that
    domain -- same as a normal browser remembering you're signed in.
  - "Find another source" runs a web search on the article's title in the
    same browser, so the user can pick a different, non-paywalled outlet
    covering the same story themselves -- plain search/discovery, not
    circumvention.

Verified live: search opened a real, interactive Google results page with
working title-bar sync; back navigation (via BackHandler, goBack() when the
WebView has history, else pop the screen) returned cleanly to the article.

1 files changed, 48 insertions, 3 deletions

diff --git a/app/src/main/java/org/terst/feedreader/ui/ReaderScreen.kt b/app/src/main/java/org/terst/feedreader/ui/ReaderScreen.kt
index ced9482..8c2f64e 100644
--- a/app/src/main/java/org/terst/feedreader/ui/ReaderScreen.kt
+++ b/app/src/main/java/org/terst/feedreader/ui/ReaderScreen.kt
@@ -16,9 +16,12 @@ import androidx.compose.material.icons.filled.Bookmark
 import androidx.compose.material.icons.filled.BookmarkBorder
 import androidx.compose.material.icons.filled.CloudDone
 import androidx.compose.material.icons.filled.CloudUpload
+import androidx.compose.material.icons.filled.MoreVert
 import androidx.compose.material.icons.filled.OpenInBrowser
 import androidx.compose.material.icons.outlined.Article
 import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.DropdownMenu
+import androidx.compose.material3.DropdownMenuItem
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.Icon
 import androidx.compose.material3.IconButton
@@ -50,6 +53,7 @@ import org.terst.feedreader.data.Settings
 import org.terst.feedreader.readability.ReaderExtractor
 import org.terst.feedreader.stash.StashClient
 import org.terst.feedreader.stash.StashSaveResult
+import java.net.URLEncoder
 
 // Below this length (of the plain feed-provided HTML), assume it's a teaser/summary,
 // not the real article body, and auto-fall-back to on-device Readability extraction.
@@ -64,7 +68,13 @@ private const val THIN_CONTENT_THRESHOLD = 500
  */
 @OptIn(ExperimentalFoundationApi::class)
 @Composable
-fun ReaderScreen(feedId: String, initialArticleId: String, onBack: () -> Unit, onOpenLink: (String) -> Unit) {
+fun ReaderScreen(
+    feedId: String,
+    initialArticleId: String,
+    onBack: () -> Unit,
+    onOpenLink: (String) -> Unit,
+    onOpenBrowser: (String) -> Unit
+) {
     val context = LocalContext.current
     val db = remember { AppDatabase.get(context) }
     var articleIds by remember(feedId) { mutableStateOf<List<String>?>(null) }
@@ -92,13 +102,23 @@ fun ReaderScreen(feedId: String, initialArticleId: String, onBack: () -> Unit, o
     val pagerState = rememberPagerState(initialPage = initialIndex) { safeIds.size }
 
     HorizontalPager(state = pagerState, modifier = Modifier.fillMaxSize()) { page ->
-        ReaderContent(articleId = safeIds[page], onBack = onBack, onOpenLink = onOpenLink)
+        ReaderContent(
+            articleId = safeIds[page],
+            onBack = onBack,
+            onOpenLink = onOpenLink,
+            onOpenBrowser = onOpenBrowser
+        )
     }
 }
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
-private fun ReaderContent(articleId: String, onBack: () -> Unit, onOpenLink: (String) -> Unit) {
+private fun ReaderContent(
+    articleId: String,
+    onBack: () -> Unit,
+    onOpenLink: (String) -> Unit,
+    onOpenBrowser: (String) -> Unit
+) {
     val context = LocalContext.current
     val db = remember { AppDatabase.get(context) }
     val scope = rememberCoroutineScope()
@@ -111,6 +131,7 @@ private fun ReaderContent(articleId: String, onBack: () -> Unit, onOpenLink: (St
     var isReaderMode by remember(articleId) { mutableStateOf(false) }
     var isExtracting by remember(articleId) { mutableStateOf(false) }
     var isSaving by remember(articleId) { mutableStateOf(false) }
+    var moreMenuExpanded by remember(articleId) { mutableStateOf(false) }
 
     LaunchedEffect(articleId) {
         val loaded = db.articleDao().getById(articleId) ?: return@LaunchedEffect
@@ -250,6 +271,30 @@ private fun ReaderContent(articleId: String, onBack: () -> Unit, onOpenLink: (St
                             contentDescription = "Save to Stash"
                         )
                     }
+                    IconButton(onClick = { moreMenuExpanded = true }) {
+                        Icon(Icons.Default.MoreVert, contentDescription = "More")
+                    }
+                    DropdownMenu(expanded = moreMenuExpanded, onDismissRequest = { moreMenuExpanded = false }) {
+                        // A real (JS-on) browser, not the extraction pipeline -- search results
+                        // and login pages need actual interaction, not a Readability pass.
+                        DropdownMenuItem(
+                            text = { Text("Find another source") },
+                            onClick = {
+                                moreMenuExpanded = false
+                                val a = currentArticle ?: return@DropdownMenuItem
+                                val query = URLEncoder.encode(a.title, "UTF-8")
+                                onOpenBrowser("https://www.google.com/search?q=$query")
+                            }
+                        )
+                        DropdownMenuItem(
+                            text = { Text("Log in to this site") },
+                            onClick = {
+                                moreMenuExpanded = false
+                                val a = currentArticle ?: return@DropdownMenuItem
+                                onOpenBrowser(a.link)
+                            }
+                        )
+                    }
                 }
             )
         },