Stop reader mode passing a site's cookie notice off as the article

Reported live: reader mode on a New Republic feature showed nothing but
the cookie disclaimer, and had cached it.

Reproduced outside the app by running ReaderExtractor's own injected
script (Readability.js and all) against the real page. With the article
body present, extraction is perfect. With the body absent from the DOM at
the moment the script runs, Readability's first pass -- which discards
"unlikely candidates", and the Didomi banner's class is
didomi-notice-banner -- comes back under its own 500-character threshold,
so it retries with that stripping switched off. The banner's single
paragraph is 510 characters, i.e. just over the threshold, so it comes
back as the article with the right title attached.

Nothing on the Kotlin side looked at that. Any non-blank content counted
as ExtractionResult.Success, was written to articles.extractedContent,
and was never reconsidered -- so one bad load became a permanent cookie
disclaimer, which is the "extractedContent cached: true" in the report.

ConsentNotice recognises such a result: a hard plain-text length cap
first (nothing long is ever rejected, however much consent boilerplate it
quotes), then either a known CMP container id -- Readability strips
classes but keeps ids -- or two or more distinct consent phrases.

The accept/retry/give-up decision moves out of the WebView callback into
decideEvalOutcome so it can be tested without a device. A consent notice
is now "not ready yet", which routes it into the retry the extractor
already does for an empty result; if it survives all six attempts that is
what the page serves, and it fails as ExtractionFailure.ConsentInterstitial
rather than being accepted.

A fixed extractor cannot repair what is already on disk, so
loadCachedExtraction drops a cached notice on read and re-extracts, in
both ReaderScreen and LinkReaderScreen. No schema change: the repair
happens when the article is next opened. Reader mode is still never
turned on heuristically -- replacing a discarded notice does not flip it.

The bug report now also carries the last extraction error, without which
a report about bad reader content cannot say whether extraction failed.

Tests: 59 -> 78.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018AwnALZL6bD4VBtATDVv3B

1 files changed, 61 insertions, 0 deletions

diff --git a/app/src/main/java/org/terst/feedreader/readability/EvalDecision.kt b/app/src/main/java/org/terst/feedreader/readability/EvalDecision.kt
new file mode 100644
index 0000000..ed0033d
--- /dev/null
+++ b/app/src/main/java/org/terst/feedreader/readability/EvalDecision.kt
@@ -0,0 +1,61 @@
+package org.terst.feedreader.readability
+
+/** What to do with one `evaluateJavascript` result. */
+sealed interface EvalDecision {
+    /** Nothing more to try: this is the extraction's outcome. */
+    data class Done(val result: ExtractionResult) : EvalDecision
+
+    /** The page probably was not ready; inject the script again. */
+    data object Retry : EvalDecision
+}
+
+/**
+ * Decides, for one script result, whether extraction succeeded, should be
+ * retried, or has failed and why.
+ *
+ * Lifted out of the WebView callback it used to live inside so it can be
+ * exercised without a device. The bug that prompted that: a result consisting
+ * only of the page's cookie-consent banner was non-blank and error-free, so it
+ * counted as a success, was cached to `articles.extractedContent`, and was never
+ * reconsidered. Reported live as "reader mode just extracts cookie disclaimer".
+ */
+internal fun decideEvalOutcome(
+    article: ExtractedArticle?,
+    rawResult: String,
+    attempt: Int,
+    maxAttempts: Int
+): EvalDecision {
+    val readabilityError = article?.error?.takeIf { it.isNotBlank() }
+    // A banner is exactly what a half-loaded page produces -- the consent script
+    // runs early, the article body may not be in the DOM yet -- so this is not
+    // usable, which routes it into the same retry the extractor already does for
+    // an empty result rather than being accepted.
+    val isConsentNotice = article != null &&
+        readabilityError == null &&
+        ConsentNotice.looksLikeConsentNotice(article.content)
+    val usable = article != null &&
+        readabilityError == null &&
+        !article.content.isNullOrBlank() &&
+        !isConsentNotice
+
+    return when {
+        usable -> EvalDecision.Done(ExtractionResult.Success(article!!))
+
+        // Readability ran and objected: that verdict will not change.
+        readabilityError != null ->
+            EvalDecision.Done(ExtractionResult.Failure(ExtractionFailure.ReadabilityError(readabilityError)))
+
+        attempt < maxAttempts -> EvalDecision.Retry
+
+        // Every attempt came back with nothing but the consent notice, so this is
+        // what the page actually serves -- report it as its own failure rather
+        // than passing a cookie disclaimer off as the article.
+        isConsentNotice ->
+            EvalDecision.Done(ExtractionResult.Failure(ExtractionFailure.ConsentInterstitial))
+
+        article == null ->
+            EvalDecision.Done(ExtractionResult.Failure(ExtractionFailure.BadResult(rawResult)))
+
+        else -> EvalDecision.Done(ExtractionResult.Failure(ExtractionFailure.NoContent))
+    }
+}