fix: search books by author and series

app/build.gradle.kts

@@ -11,8 +11,8 @@ android {
         applicationId = "com.aletheia.app"
         minSdk = 24
         targetSdk = 36
-        versionCode = 44
+        versionCode = 45
-        versionName = "2.33"
+        versionName = "2.34"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
         vectorDrawables {

app/src/main/java/com/aletheia/app/data/OpdsCatalogParser.kt

@@ -9,6 +9,11 @@ import org.w3c.dom.Document
 import org.w3c.dom.Element
 import org.xml.sax.InputSource
 
+data class OpdsNavigationEntry(
+    val title: String,
+    val url: String
+)
+
 object OpdsCatalogParser {
     fun isOpdsFeed(xml: String): Boolean = runCatching {
         val root = parseDocument(xml).documentElement
@@ -18,6 +23,30 @@ object OpdsCatalogParser {
     fun parseBooks(xml: String, resolveUrl: (String) -> String): List<QBooksBook> =
         parsePage(xml, resolveUrl).books
 
+    fun parseNavigationEntries(xml: String, resolveUrl: (String) -> String): List<OpdsNavigationEntry> {
+        val document = parseDocument(xml)
+        val root = document.documentElement
+        require(root.localName == "feed" && root.namespaceURI == ATOM_NAMESPACE) {
+            "Сервер вернул документ, который не является OPDS-каталогом."
+        }
+
+        val entries = document.getElementsByTagNameNS(ATOM_NAMESPACE, "entry")
+        return buildList {
+            for (index in 0 until entries.length) {
+                val entry = entries.item(index) as? Element ?: continue
+                val title = entry.firstText(ATOM_NAMESPACE, "title").trim()
+                if (title.isBlank()) continue
+                val catalogLink = entry.childElements("link").firstOrNull { link ->
+                    val type = link.getAttribute("type").substringBefore(';').trim()
+                    val rel = link.getAttribute("rel").trim()
+                    type.equals(ATOM_MEDIA_TYPE, ignoreCase = true) && rel.isBlank()
+                } ?: continue
+                val href = catalogLink.getAttribute("href").trim()
+                if (href.isNotBlank()) add(OpdsNavigationEntry(title, resolveUrl(href)))
+            }
+        }
+    }
+
     fun parsePage(xml: String, resolveUrl: (String) -> String): CatalogPage {
         val document = parseDocument(xml)
         val root = document.documentElement
@@ -177,6 +206,7 @@ object OpdsCatalogParser {
     )
 
     private const val ATOM_NAMESPACE = "http://www.w3.org/2005/Atom"
+    private const val ATOM_MEDIA_TYPE = "application/atom+xml"
     private const val DC_TERMS_NAMESPACE = "http://purl.org/dc/terms/"
     private val COVER_RELS = setOf(
         "http://opds-spec.org/image",

app/src/main/java/com/aletheia/app/data/QBooksService.kt

@@ -375,8 +375,25 @@ class QBooksService(
         pageSize: Int,
         pageUrl: String?
     ): CatalogPage {
+        val root = requireBaseUrl().trimEnd('/')
+        val combinedSearchPage = pageUrl
+            ?.takeIf { it.startsWith(COMBINED_SEARCH_PAGE_PREFIX) }
+            ?.removePrefix(COMBINED_SEARCH_PAGE_PREFIX)
+            ?.toIntOrNull()
+        if (isPublicOpdsRoot(root) && query.isNotBlank()) {
+            return searchPublicOpdsCatalog(
+                query = query,
+                page = (combinedSearchPage ?: page).coerceAtLeast(0),
+                pageSize = pageSize.coerceAtLeast(1)
+            )
+        }
+
         val url = pageUrl?.takeIf(String::isNotBlank) ?: buildOpdsBooksUrl(query, page.coerceAtLeast(0))
-        val parsed = openConnection(url, accept = OPDS_ACCEPT).use { connection ->
+        return fetchOpdsPage(url)
+    }
+
+    private fun fetchOpdsPage(url: String): CatalogPage =
+        openConnection(url, accept = OPDS_ACCEPT).use { connection ->
             if (connection.responseCode !in 200..299) {
                 error(qBooksHttpError(connection.responseCode))
             }
@@ -386,19 +403,143 @@ class QBooksService(
                 resolveCatalogLink(url, pathOrUrl)
             }
         }
-        return parsed
+
+    private fun fetchOpdsNavigation(url: String): List<OpdsNavigationEntry> =
+        openConnection(url, accept = OPDS_ACCEPT).use { connection ->
+            if (connection.responseCode !in 200..299) {
+                error(qBooksHttpError(connection.responseCode))
+            }
+
+            val payload = connection.inputStream.bufferedReader(Charsets.UTF_8).use { it.readText() }
+            OpdsCatalogParser.parseNavigationEntries(payload) { pathOrUrl ->
+                resolveCatalogLink(url, pathOrUrl)
+            }
+        }
+
+    private fun searchPublicOpdsCatalog(query: String, page: Int, pageSize: Int): CatalogPage {
+        val root = requireBaseUrl().trimEnd('/')
+        val directPage = fetchOpdsPage(buildPublicSearchUrl(root, "books", query, page))
+        val authorEntries = findAuthorEntries(root, query)
+        val rankedAuthors = rankNavigationEntries(authorEntries, query).take(MAX_AUTHOR_SEARCH_FEEDS)
+        val authorPages = rankedAuthors.mapNotNull { entry ->
+            val url = entry.url.trimEnd('/') + "/alphabet" + pageSuffix(page)
+            runCatching { fetchOpdsPage(url) }.getOrNull()
+        }
+        val sequenceEntries = runCatching {
+            fetchOpdsNavigation("$root/sequences/${encodePathSegment(query)}")
+        }.getOrDefault(emptyList())
+        val sequencePages = rankNavigationEntries(sequenceEntries, query)
+            .take(MAX_SEQUENCE_SEARCH_FEEDS)
+            .mapNotNull { entry ->
+                runCatching { fetchOpdsPage(entry.url.trimEnd('/') + pageSuffix(page)) }.getOrNull()
+            }
+
+        val pages = buildList {
+            add(directPage)
+            addAll(authorPages)
+            addAll(sequencePages)
+        }
+        val books = mergeSearchResults(pages.map(CatalogPage::books), pageSize)
+        val hasNextPage = pages.any { !it.nextPageUrl.isNullOrBlank() }
+        return CatalogPage(
+            books = books,
+            nextPageUrl = if (hasNextPage) "$COMBINED_SEARCH_PAGE_PREFIX${page + 1}" else null
+        )
+    }
+
+    private fun findAuthorEntries(root: String, query: String): List<OpdsNavigationEntry> {
+        for (term in authorSearchTerms(query)) {
+            val entries = runCatching {
+                fetchOpdsNavigation(buildPublicSearchUrl(root, "authors", term, page = 0))
+            }.getOrDefault(emptyList())
+            if (entries.isNotEmpty()) return entries
+        }
+        return emptyList()
+    }
+
+    private fun authorSearchTerms(query: String): List<String> {
+        val terms = query.trim().split(METADATA_WHITESPACE).filter { it.length > 1 }
+        return buildList {
+            add(query.trim())
+            terms.sortedByDescending(String::length).forEach(::add)
+        }.filter(String::isNotBlank).distinctBy { it.lowercase(Locale.ROOT) }
+    }
+
+    private fun rankNavigationEntries(
+        entries: List<OpdsNavigationEntry>,
+        query: String
+    ): List<OpdsNavigationEntry> {
+        val normalizedQuery = query.normalizedMetadataText()
+        val queryTokens = normalizedQuery.split(' ').filter(String::isNotBlank).toSet()
+        return entries.withIndex()
+            .sortedWith(
+                compareByDescending<IndexedValue<OpdsNavigationEntry>> { indexed ->
+                    val title = indexed.value.title.normalizedMetadataText()
+                    val titleTokens = title.split(' ').filter(String::isNotBlank).toSet()
+                    when {
+                        title == normalizedQuery -> 10_000
+                        titleTokens == queryTokens -> 9_000
+                        queryTokens.isNotEmpty() && titleTokens.containsAll(queryTokens) -> 7_000
+                        title.startsWith(normalizedQuery) -> 5_000
+                        title.contains(normalizedQuery) -> 4_000
+                        else -> titleTokens.intersect(queryTokens).size * 100
+                    }
+                }.thenBy { it.index }
+            )
+            .map(IndexedValue<OpdsNavigationEntry>::value)
+    }
+
+    private fun mergeSearchResults(
+        sources: List<List<QBooksBook>>,
+        pageSize: Int
+    ): List<QBooksBook> {
+        val result = mutableListOf<QBooksBook>()
+        val seen = mutableSetOf<String>()
+        val positions = IntArray(sources.size)
+        while (result.size < pageSize) {
+            var addedThisRound = false
+            sources.forEachIndexed { sourceIndex, books ->
+                while (positions[sourceIndex] < books.size) {
+                    val book = books[positions[sourceIndex]++]
+                    val key = book.id.ifBlank { book.downloadUrl }
+                    if (seen.add(key)) {
+                        result += book
+                        addedThisRound = true
+                        break
+                    }
+                }
+                if (result.size >= pageSize) return result
+            }
+            if (!addedThisRound) break
+        }
+        return result
+    }
+
+    private fun buildPublicSearchUrl(root: String, type: String, query: String, page: Int): String =
+        "$root/search?searchType=$type&searchTerm=${encodeQueryParameter(query)}&pageNumber=$page"
+
+    private fun encodeQueryParameter(value: String): String =
+        URLEncoder.encode(value, Charsets.UTF_8.name())
+
+    private fun encodePathSegment(value: String): String =
+        encodeQueryParameter(value).replace("+", "%20")
+
+    private fun pageSuffix(page: Int): String = if (page <= 0) "" else "/$page"
+
+    private fun isPublicOpdsRoot(root: String): Boolean {
+        val uri = URI(root)
+        return uri.host.equals(FLIBUSTA_HOST, ignoreCase = true) &&
+            uri.path.trimEnd('/').equals("/opds", ignoreCase = true)
     }
 
     private fun buildOpdsBooksUrl(query: String, page: Int): String {
         val root = requireBaseUrl().trimEnd('/')
-        val uri = URI(root)
+        val isPublicCatalog = isPublicOpdsRoot(root)
-        val isFlibusta = uri.host.equals(FLIBUSTA_HOST, ignoreCase = true) &&
+        val encodedQuery = encodeQueryParameter(query)
-            uri.path.trimEnd('/').equals("/opds", ignoreCase = true)
-        val encodedQuery = URLEncoder.encode(query, Charsets.UTF_8.name())
 
         return when {
-            isFlibusta && query.isBlank() -> "$root/new/$page/new"
+            isPublicCatalog && query.isBlank() -> "$root/new/$page/new"
-            isFlibusta -> "$root/search?searchType=books&searchTerm=$encodedQuery&pageNumber=$page"
+            isPublicCatalog -> "$root/search?searchType=books&searchTerm=$encodedQuery&pageNumber=$page"
             query.isBlank() -> root
             else -> "$root/search?searchTerm=$encodedQuery"
         }
@@ -476,6 +617,7 @@ class QBooksService(
 
     private fun catalogCacheKey(searchQuery: String, page: Int, pageUrl: String?): String =
         listOf(
+            if (searchQuery.isBlank()) CATALOG_CACHE_SCHEMA else SEARCH_CACHE_SCHEMA,
             requireBaseUrl(),
             username.orEmpty(),
             searchQuery.trim().lowercase(Locale.ROOT),
@@ -607,6 +749,11 @@ class QBooksService(
         private const val USER_AGENT = "Aletheia/2.28"
         private const val OPDS_ACCEPT = "application/atom+xml, application/xml;q=0.9, */*;q=0.8"
         private const val FLIBUSTA_HOST = "m.flibusta.is"
+        private const val COMBINED_SEARCH_PAGE_PREFIX = "aletheia-opds-search-page:"
+        private const val CATALOG_CACHE_SCHEMA = "catalog-v1"
+        private const val SEARCH_CACHE_SCHEMA = "search-v2"
+        private const val MAX_AUTHOR_SEARCH_FEEDS = 2
+        private const val MAX_SEQUENCE_SEARCH_FEEDS = 1
         private const val MAX_DOWNLOAD_REDIRECTS = 5
         private val REDIRECT_RESPONSE_CODES = setOf(301, 302, 303, 307, 308)
         private val UNKNOWN_AUTHORS = setOf("", "unknown", "unknown author", "неизвестный автор")

app/src/main/res/layout/fragment_qbooks_library.xml

@@ -44,6 +44,8 @@
             android:layout_height="match_parent"
             app:boxBackgroundMode="none"
             app:endIconMode="clear_text"
+            app:endIconTint="@color/ink_soft_color"
+            app:hintEnabled="false"
             app:startIconDrawable="@drawable/ic_nav_search"
             app:startIconTint="@color/ink_soft_color">
 
@@ -52,8 +54,11 @@
                 android:layout_width="match_parent"
                 android:layout_height="match_parent"
                 android:background="@android:color/transparent"
+                android:gravity="center_vertical"
                 android:hint="@string/label_search_qbooks"
                 android:imeOptions="actionSearch"
+                android:paddingTop="0dp"
+                android:paddingBottom="0dp"
                 android:singleLine="true"
                 android:textColor="@color/ink_color"
                 android:textColorHint="@color/ink_soft_color"

app/src/test/java/com/aletheia/app/data/OpdsCatalogParserTest.kt

@@ -31,6 +31,17 @@ class OpdsCatalogParserTest {
         assertTrue(books.isEmpty())
     }
 
+    @Test
+    fun parsesOnlyPrimaryNavigationLinks() {
+        val entries = OpdsCatalogParser.parseNavigationEntries(AUTHOR_NAVIGATION_FEED) { href ->
+            "https://books.example$href"
+        }
+
+        assertEquals(1, entries.size)
+        assertEquals("Азимов Айзек", entries.single().title)
+        assertEquals("https://books.example/opds/author/656", entries.single().url)
+    }
+
     @Test
     fun returnsResolvedNextPageEvenWhenSomeEntriesAreFilteredOut() {
         val page = OpdsCatalogParser.parsePage(PAGINATED_FEED) { href -> "https://books.example$href" }
@@ -113,5 +124,19 @@ class OpdsCatalogParserTest {
                 </entry>
             </feed>
         """.trimIndent()
+
+        private val AUTHOR_NAVIGATION_FEED = """
+            <?xml version="1.0" encoding="utf-8"?>
+            <feed xmlns="http://www.w3.org/2005/Atom">
+                <entry>
+                    <id>tag:author:656</id>
+                    <title>Азимов Айзек</title>
+                    <link type="application/atom+xml;profile=opds-catalog" href="/opds/author/656" />
+                    <link rel="http://www.feedbooks.com/opds/facet"
+                          type="application/atom+xml;profile=opds-catalog"
+                          href="/opds/authorsequences/656" />
+                </entry>
+            </feed>
+        """.trimIndent()
     }
 }