feat: 优化代码

app/src/main/java/io/legado/app/model/localBook/AnalyzeTxtFile.kt

@@ -13,34 +13,43 @@ import java.nio.charset.Charset
 import java.util.regex.Matcher
 import java.util.regex.Pattern
 
-object AnalyzeTxtFile {
+class AnalyzeTxtFile {
-    private const val folderName = "bookTxt"
-    private const val BLANK: Byte = 0x0a
-
-    //默认从文件中获取数据的长度
-    private const val BUFFER_SIZE = 512 * 1024
 
-    //没有标题的时候，每个章节的最大长度
+    private val tocRules = arrayListOf<TxtTocRule>()
-    private const val MAX_LENGTH_WITH_NO_CHAPTER = 10 * 1024
+    private lateinit var charset: Charset
-    val cacheFolder: File by lazy {
-        val rootFile = App.INSTANCE.getExternalFilesDir(null)
-            ?: App.INSTANCE.externalCacheDir
-            ?: App.INSTANCE.cacheDir
-        FileUtils.createFolderIfNotExist(rootFile, subDirs = *arrayOf(folderName))
-    }
 
     fun analyze(context: Context, book: Book): ArrayList<BookChapter> {
         val bookFile = getBookFile(context, book)
         book.charset = EncodingDetect.getEncode(bookFile)
-        val charset = book.fileCharset()
+        charset = book.fileCharset()
-        val toc = arrayListOf<BookChapter>()
+        val rulePattern = if (book.tocUrl.isNotEmpty()) {
+            Pattern.compile(book.tocUrl, Pattern.MULTILINE)
+        } else {
+            tocRules.addAll(getTocRules())
+            null
+        }
         //获取文件流
         val bookStream = RandomAccessFile(bookFile, "r")
-        val rulePattern = getTocRule(book, bookStream, charset)
+        return analyze(bookStream, book, rulePattern)
+    }
 
+    private fun analyze(
+        bookStream: RandomAccessFile,
+        book: Book,
+        pattern: Pattern?
+    ): ArrayList<BookChapter> {
+        val toc = arrayListOf<BookChapter>()
+        var tocRule: TxtTocRule? = null
+        val rulePattern = pattern ?: let {
+            tocRule = getTocRule(bookStream)
+            tocRule?.let {
+                Pattern.compile(it.rule, Pattern.MULTILINE)
+            }
+        }
         //加载章节
         val buffer = ByteArray(BUFFER_SIZE)
         //获取到的块起始点，在文件中的位置
+        bookStream.seek(0)
         var curOffset: Long = 0
         //block的个数
         var blockPos = 0
@@ -70,6 +79,10 @@ object AnalyzeTxtFile {
                     val chapterStart = matcher.start()
                     //获取章节内容
                     val chapterContent = blockContent.substring(seekPos, chapterStart)
+                    if (chapterContent.length > 30000 && pattern == null) {
+                        tocRules.remove(tocRule)
+                        return analyze(bookStream, book, null)
+                    }
                     //如果 seekPos == 0 && nextChapterPos != 0 表示当前block处前面有一段内容
                     //第一种情况一定是序章 第二种情况可能是上一个章节的内容
                     if (seekPos == 0 && chapterStart != 0) { //获取当前章节的内容
@@ -161,9 +174,46 @@ object AnalyzeTxtFile {
 
         System.gc()
         System.runFinalization()
+        tocRule?.let {
+            book.tocUrl = it.rule
+        }
         return toc
     }
 
+    private fun getTocRule(bookStream: RandomAccessFile): TxtTocRule? {
+        var txtTocRule: TxtTocRule? = null
+        //首先获取128k的数据
+        val buffer = ByteArray(BUFFER_SIZE / 4)
+        val length = bookStream.read(buffer, 0, buffer.size)
+        val content = String(buffer, 0, length, charset)
+        for (tocRule in tocRules) {
+            val pattern = Pattern.compile(tocRule.rule, Pattern.MULTILINE)
+            val matcher = pattern.matcher(content)
+            if (matcher.find()) {
+                txtTocRule = tocRule
+                break
+            }
+        }
+
+        return txtTocRule
+    }
+
+    companion object {
+        private const val folderName = "bookTxt"
+        private const val BLANK: Byte = 0x0a
+
+        //默认从文件中获取数据的长度
+        private const val BUFFER_SIZE = 512 * 1024
+
+        //没有标题的时候，每个章节的最大长度
+        private const val MAX_LENGTH_WITH_NO_CHAPTER = 10 * 1024
+        val cacheFolder: File by lazy {
+            val rootFile = App.INSTANCE.getExternalFilesDir(null)
+                ?: App.INSTANCE.externalCacheDir
+                ?: App.INSTANCE.cacheDir
+            FileUtils.createFolderIfNotExist(rootFile, subDirs = *arrayOf(folderName))
+        }
+
         fun getContent(book: Book, bookChapter: BookChapter): String {
             val bookFile = getBookFile(App.INSTANCE, book)
             //获取文件流
@@ -190,29 +240,6 @@ object AnalyzeTxtFile {
             return File(book.bookUrl)
         }
 
-    private fun getTocRule(book: Book, bookStream: RandomAccessFile, charset: Charset): Pattern? {
-        if (book.tocUrl.isNotEmpty()) {
-            return Pattern.compile(book.tocUrl, Pattern.MULTILINE)
-        }
-        val tocRules = getTocRules()
-        var rulePattern: Pattern? = null
-        //首先获取128k的数据
-        val buffer = ByteArray(BUFFER_SIZE / 4)
-        val length = bookStream.read(buffer, 0, buffer.size)
-        val content = String(buffer, 0, length, charset)
-        for (tocRule in tocRules) {
-            val pattern = Pattern.compile(tocRule.rule, Pattern.MULTILINE)
-            val matcher = pattern.matcher(content)
-            if (matcher.find()) {
-                book.tocUrl = tocRule.rule
-                rulePattern = pattern
-                break
-            }
-        }
-        bookStream.seek(0)
-        return rulePattern
-    }
-
         private fun getTocRules(): List<TxtTocRule> {
             val rules = App.db.txtTocRule().all
             if (rules.isEmpty()) {
@@ -231,3 +258,5 @@ object AnalyzeTxtFile {
             return emptyList()
         }
     }
+
+}

app/src/main/java/io/legado/app/ui/book/info/BookInfoViewModel.kt

@@ -81,7 +81,7 @@ class BookInfoViewModel(application: Application) : BaseViewModel(application) {
     ) {
         execute {
             if (book.isLocalBook()) {
-                AnalyzeTxtFile.analyze(context, book).let {
+                AnalyzeTxtFile().analyze(context, book).let {
                     App.db.bookDao().update(book)
                     App.db.bookChapterDao().insert(*it.toTypedArray())
                     chapterListData.postValue(it)

app/src/main/java/io/legado/app/ui/book/read/ReadBookViewModel.kt

@@ -102,7 +102,7 @@ class ReadBookViewModel(application: Application) : BaseViewModel(application) {
     ) {
         execute {
             if (book.isLocalBook()) {
-                AnalyzeTxtFile.analyze(context, book).let {
+                AnalyzeTxtFile().analyze(context, book).let {
                     App.db.bookChapterDao().delByBook(book.bookUrl)
                     App.db.bookChapterDao().insert(*it.toTypedArray())
                     App.db.bookDao().update(book)