fix: better handling of broken epub

Closes: #1844

komga/src/main/kotlin/org/gotson/komga/infrastructure/mediacontainer/epub/Epub.kt

@@ -20,7 +20,7 @@ data class EpubPackage(
 inline fun <R> Path.epub(block: (EpubPackage) -> R): R =
   ZipFile.builder().setPath(this).use { zip ->
     val opfFile = zip.getPackagePath()
-    val opfDoc = zip.getEntryInputStream(opfFile).use { Jsoup.parse(it, null, "", Parser.xmlParser()) }
+    val opfDoc = zip.getEntryInputStream(opfFile)?.use { Jsoup.parse(it, null, "", Parser.xmlParser()) } ?: throw MediaUnsupportedException("Could not open OPF resource")
     val opfDir = Paths.get(opfFile).parent
     block(EpubPackage(zip, opfDoc, opfDir, opfDoc.getManifest()))
   }
@@ -30,9 +30,9 @@ inline fun <R> Path.epub(block: (EpubPackage) -> R): R =
  */
 fun ZipFile.getPackagePath(): String =
   getEntryInputStream("META-INF/container.xml")
-    .use { Jsoup.parse(it, null, "") }
-    .getElementsByTag("rootfile")
-    .first()
+    ?.use { Jsoup.parse(it, null, "") }
+    ?.getElementsByTag("rootfile")
+    ?.first()
     ?.attr("full-path") ?: throw MediaUnsupportedException("META-INF/container.xml does not contain rootfile tag")
 
 /**
@@ -41,7 +41,7 @@ fun ZipFile.getPackagePath(): String =
 fun getPackageFileContent(path: Path): String? =
   ZipFile.builder().setPath(path).use { zip ->
     try {
-      zip.getEntryInputStream(zip.getPackagePath()).reader().use { it.readText() }
+      zip.getEntryInputStream(zip.getPackagePath())?.reader()?.use { it.readText() }
     } catch (e: Exception) {
       null
     }

komga/src/main/kotlin/org/gotson/komga/infrastructure/mediacontainer/epub/EpubExtractor.kt

@@ -70,10 +70,12 @@ class EpubExtractor(
         val href = coverManifestItem.href
         val mediaType = coverManifestItem.mediaType
         val coverPath = normalizeHref(opfDir, href)
-        TypedBytes(
-          zip.getEntryBytes(coverPath),
-          mediaType,
-        )
+        zip.getEntryBytes(coverPath)?.let { coverBytes ->
+          TypedBytes(
+            coverBytes,
+            mediaType,
+          )
+        }
       } else {
         null
       }
@@ -151,7 +153,7 @@ class EpubExtractor(
           .map { it.attr("idref") }
           .mapNotNull { idref -> epub.manifest[idref]?.href?.let { normalizeHref(epub.opfDir, it) } }
           .map { pagePath ->
-            val doc = epub.zip.getEntryInputStream(pagePath).use { Jsoup.parse(it, null, "") }
+            val doc = epub.zip.getEntryInputStream(pagePath)?.use { Jsoup.parse(it, null, "") } ?: return@map emptyList()
 
             // if a page has text over the threshold then the book is not divina compatible
             if (doc.body().text().length > letterCountThreshold) return emptyList()
@@ -217,8 +219,8 @@ class EpubExtractor(
       val readingOrder = resources.filter { it.subType == MediaFile.SubType.EPUB_PAGE }
 
       readingOrder.forEach { mediaFile ->
-        val doc = epub.zip.getEntryInputStream(mediaFile.fileName).use { Jsoup.parse(it, null, "") }
-        if (!doc.getElementsByClass("koboSpan").isNullOrEmpty()) return true
+        val doc = epub.zip.getEntryInputStream(mediaFile.fileName)?.use { Jsoup.parse(it, null, "") }
+        if (!doc?.getElementsByClass("koboSpan").isNullOrEmpty()) return true
       }
     } catch (e: Exception) {
       logger.warn(e) { "Error while checking if EPUB is KEPUB" }
@@ -257,7 +259,7 @@ class EpubExtractor(
     val koboPositions =
       when {
         isFixedLayout -> emptyMap()
-        isKepub -> computePositionsFromKoboSpan(readingOrder) { filename -> epub.zip.getEntryInputStream(filename).use { it.readBytes().decodeToString() } }
+        isKepub -> computePositionsFromKoboSpan(readingOrder) { filename -> epub.zip.getEntryInputStream(filename).use { it?.readBytes()?.decodeToString() } }
         kepubConverter.isAvailable -> {
           try {
             val kepub =
@@ -327,12 +329,12 @@ class EpubExtractor(
    */
   private fun computePositionsFromKoboSpan(
     readingOrder: List<MediaFile>,
-    resourceSupplier: (String) -> String,
-  ): Map<String, List<Pair<String, Float>>> =
+    resourceSupplier: (String) -> String?,
+  ): Map<String, List<Pair<String, Float>>?> =
     readingOrder.associate { file ->
-      val doc = Jsoup.parse(resourceSupplier(file.fileName), Parser.htmlParser().setTrackPosition(true))
+      val doc = resourceSupplier(file.fileName)?.let { resource -> Jsoup.parse(resource, Parser.htmlParser().setTrackPosition(true)) }
       file.fileName to
-        doc.select("span.koboSpan").mapNotNull { koboSpan ->
+        doc?.select("span.koboSpan")?.mapNotNull { koboSpan ->
           val id = koboSpan.id()
           if (!id.isNullOrBlank()) {
             // progression is built from the position in the file of each koboSpan, divided by the file size

komga/src/main/kotlin/org/gotson/komga/infrastructure/mediacontainer/epub/Nav.kt

@@ -11,7 +11,9 @@ import kotlin.io.path.Path
 fun EpubPackage.getNavResource(): ResourceContent? =
   manifest.values.firstOrNull { it.properties.contains("nav") }?.let { nav ->
     val href = normalizeHref(opfDir, nav.href)
-    ResourceContent(Path(href), zip.getEntryBytes(href).decodeToString())
+    zip.getEntryBytes(href)?.decodeToString()?.let { navContent ->
+      ResourceContent(Path(href), navContent)
+    }
   }
 
 fun processNav(

komga/src/main/kotlin/org/gotson/komga/infrastructure/mediacontainer/epub/Ncx.kt

@@ -13,7 +13,9 @@ private val possibleNcxItemIds = listOf("toc", "ncx", "ncxtoc")
 fun EpubPackage.getNcxResource(): ResourceContent? =
   (manifest.values.firstOrNull { it.mediaType == "application/x-dtbncx+xml" } ?: manifest.values.firstOrNull { possibleNcxItemIds.contains(it.id) })?.let { ncx ->
     val href = normalizeHref(opfDir, ncx.href)
-    ResourceContent(Path(href), zip.getEntryBytes(href).decodeToString())
+    zip.getEntryBytes(href)?.decodeToString()?.let { ncxContent ->
+      ResourceContent(Path(href), ncxContent)
+    }
   }
 
 fun processNcx(

komga/src/main/kotlin/org/gotson/komga/infrastructure/util/ZipFileUtils.kt

@@ -7,9 +7,9 @@ import java.nio.file.Path
 
 inline fun <R> ZipFile.Builder.use(block: (ZipFile) -> R) = this.get().use(block)
 
-fun ZipFile.getEntryInputStream(entryName: String): InputStream = this.getInputStream(this.getEntry(entryName))
+fun ZipFile.getEntryInputStream(entryName: String): InputStream? = this.getEntry(entryName)?.let { entry -> this.getInputStream(entry) }
 
-fun ZipFile.getEntryBytes(entryName: String): ByteArray = this.getInputStream(this.getEntry(entryName)).use { it.readBytes() }
+fun ZipFile.getEntryBytes(entryName: String): ByteArray? = this.getEntry(entryName)?.let { entry -> this.getInputStream(entry).use { it.readBytes() } }
 
 fun getZipEntryBytes(
   path: Path,