some refactoring

lib/eval/lnreader/js_cheerio.dart

@@ -219,17 +219,45 @@ class ElementCollection {
     this.elements = elements;
   }
 
+  text() {
+    return this.map(function(i, el) {
+      return el.text();
+    }).toArray().join("\\n") ?? "";
+  }
+
+  html() {
+    return this.first()?.html();
+  }
+
+  outerHtml() {
+    return this.first()?.outerHtml();
+  }
+
+  attr(name) {
+    return this.first()?.attr(name);
+  }
+
+  hasClass(cls) {
+    return this.first()?.hasClass(cls);
+  }
+
   each(fn) {
     this.elements.forEach((el, i) => fn(i, el));
     return this;
   }
 
   map(fn) {
-    return this.elements.map((el, i) => fn(el, i));
+    return new ElementCollection(this.elements.map((el, i) => fn(i, el)));
   }
 
   filter(fn) {
-    return new ElementCollection(this.elements.filter((el, i) => fn(el, i)));
+    return new ElementCollection(this.elements.filter(function (el, i) {
+      try {
+        return fn(i, el);
+      } catch (_) {
+        return false;
+      }
+    }));
   }
 
   addClass(cls) {
@@ -309,37 +337,62 @@ class ElementCollection {
   }
 
   first() {
-    return this.elements[0] || null;
+    return this.get(0);
   }
 
   last() {
-    return this.elements[this.elements.length - 1] || null;
+    return this.get(this.elements.length - 1);
   }
 
   get(index) {
-    return this.elements[index] || null;
+    return this.elements[index] || new Stub();
   }
 
   length() {
     return this.elements.length;
   }
 
+  toArray() {
+    return this.elements;
+  }
+
   [Symbol.iterator]() {
     return this.elements[Symbol.iterator]();
   }
 }
 
+class Stub {
+  text() {
+    return null;
+  }
+  html() {
+    return null;
+  }
+  outerHtml() {
+    return null;
+  }
+  val() {
+    return null;
+  }
+  attr(name) {
+    return null;
+  }
+  hasClass(cls) {
+    return false;
+  }
+}
+
 function load(html) {
   const rootKey = sendMessage("load", JSON.stringify([html]));
   const root = new Element(rootKey);
 
   const \$ = function(input) {
-    if (typeof input === "string") {
+    if (input instanceof ElementCollection) {
-      return root.find(input); // returns ElementCollection
-    } else if (input instanceof ElementCollection) {
       return input;
     } else if (input instanceof Element) {
       return input;
+    } else if (typeof input === "string") {
+      return root.find(input); // returns ElementCollection
     } else if (input && input._key) {
       return new ElementCollection([new Element(input._key)]);
     } else {
@@ -347,6 +400,9 @@ function load(html) {
     }
   };
 
+  \$.html = function() {
+    return root.html();
+  };
   \$.root = root;
   \$.Element = Element;
   \$.Collection = ElementCollection;

lib/eval/lnreader/js_libs.dart

@@ -72,6 +72,10 @@ String.prototype.substringBetween = function(left, right) {
     return this.substring(leftIndex, rightIndex);
 }
 
+async function jsonStringify(fn) {
+    return JSON.stringify(await fn());
+}
+
 const isUrlAbsolute = url => {
   if (url) {
     if (url.indexOf("//") === 0) {

lib/eval/lnreader/js_polyfills.dart

@@ -6,7 +6,19 @@ class JsPolyfills {
 
   void init() {
     runtime.evaluate('''
-const global="object"==typeof globalThis?globalThis:"object"==typeof window?window:"object"==typeof self?self:this,_FormData=global.FormData,_send=global.XMLHttpRequest&&global.XMLHttpRequest.prototype.send,_fetch=global.Request&&global.fetch,_sendBeacon=global.navigator&&global.navigator.sendBeacon,_match=global.Element&&global.Element.prototype,stringTag=global.Symbol&&Symbol.toStringTag;function ensureArgs(e,t){if(e.length<t)throw new TypeError(`\${t} argument required, but only \${e.length} present.`)}function normalizeArgs(e,t,a){return[String(e),String(t)]}function normalizeLinefeeds(e){return e.replace(/\r?\n|\r/g,"\r\n")}function each(e,t){for(let a=0;a<e.length;a++)t(e[a])}stringTag&&"File"in global&&!File.prototype[stringTag]&&(File.prototype[stringTag]="File");const escape=e=>e.replace(/\n/g,"%0A").replace(/\r/g,"%0D").replace(/"/g,"%22");class FormData{constructor(e){this._data=[];const t=this;e&&each(e.elements,(e=>{if(e.name&&!e.disabled&&"submit"!==e.type&&"button"!==e.type&&!e.matches("form fieldset[disabled] *"))if("file"===e.type){each(e.files&&e.files.length?e.files:[new File([],"",{type:"application/octet-stream"})],(a=>{t.append(e.name,a)}))}else if("select-multiple"===e.type||"select-one"===e.type)each(e.options,(a=>{!a.disabled&&a.selected&&t.append(e.name,a.value)}));else if("checkbox"===e.type||"radio"===e.type)e.checked&&t.append(e.name,e.value);else{const a="textarea"===e.type?normalizeLinefeeds(e.value):e.value;t.append(e.name,a)}}))}append(e,t,a){ensureArgs(arguments,2),this._data.push(normalizeArgs(e,t,a))}delete(e){ensureArgs(arguments,1);const t=[];e=String(e),each(this._data,(a=>{a[0]!==e&&t.push(a)})),this._data=t}*entries(){for(var e=0;e<this._data.length;e++)yield this._data[e]}forEach(e,t){ensureArgs(arguments,1);for(const[a,n]of this)e.call(t,n,a,this)}get(e){ensureArgs(arguments,1);const t=this._data;e=String(e);for(let a=0;a<t.length;a++)if(t[a][0]===e)return t[a][1];return null}getAll(e){ensureArgs(arguments,1);const t=[];return e=String(e),each(this._data,(a=>{a[0]===e&&t.push(a[1])})),t}has(e){ensureArgs(arguments,1),e=String(e);for(let t=0;t<this._data.length;t++)if(this._data[t][0]===e)return!0;return!1}*keys(){for(const[e]of this)yield e}set(e,t,a){ensureArgs(arguments,2),e=String(e);const n=[],r=normalizeArgs(e,t,a);let s=!0;each(this._data,(t=>{t[0]===e?s&&(s=!n.push(r)):n.push(t)})),s&&n.push(r),this._data=n}*values(){for(const[,e]of this)yield e}_asNative(){const e=new _FormData;for(const[t,a]of this)e.append(t,a);return e}_blob(){const e="----formdata-polyfill-"+Math.random(),t=[],a=`--\${e}\r\nContent-Disposition: form-data; name="`;return this.forEach(((e,n)=>"string"==typeof e?t.push(a+escape(normalizeLinefeeds(n))+`"\r\n\r\n\${normalizeLinefeeds(e)}\r\n`):t.push(a+escape(normalizeLinefeeds(n))+`"; filename="\${escape(e.name)}"\r\nContent-Type: \${e.type||"application/octet-stream"}\r\n\r\n`,e,"\r\n"))),t.push(`--\${e}--`),new Blob(t,{type:"multipart/form-data; boundary="+e})}[Symbol.iterator](){return this.entries()}toString(){return"[object FormData]"}}stringTag&&(FormData.prototype[stringTag]="FormData");
+class FormData {
+  constructor() {
+    this.params = {};
+  }
+
+  append(key, value) {
+    this.params[key] = value;
+  }
+
+  toJSON() {
+    return this.params;
+  }
+}
 ''');
     runtime.evaluate('''
 /**!

lib/eval/lnreader/m_plugin.dart

@@ -1,5 +1,3 @@
-import 'dart:convert';
-
 class ChapterItem {
   String name;
   String path;
@@ -20,9 +18,10 @@ class ChapterItem {
       name: json['name'],
       path: json['path'],
       releaseTime: json['releaseTime'],
-      chapterNumber:
+      chapterNumber: json['chapterNumber'] != null
-          int.tryParse(json['chapterNumber']) ??
+          ? (json['chapterNumber'] as num?)?.toInt() ??
-          (json['chapterNumber'] as num?)?.toInt(),
+                int.tryParse(json['chapterNumber'])
+          : null,
       page: json['page'],
     );
   }

lib/eval/lnreader/service.dart

@@ -45,9 +45,6 @@ module={},exports=Function("return this")(),Object.defineProperties(module,{name
     JsHtmlParser(runtime).init();
     JsCheerio(runtime).init();
     runtime.evaluate('''
-async function jsonStringify(fn) {
-    return JSON.stringify(await fn());
-}
 const require = (package) => {
   switch (package) {
     case "htmlparser2":