From 9bd3db39df07fb0e04cac00a1d51f597b9249d16 Mon Sep 17 00:00:00 2001
From: Dan Chen <dannvix@gmail.com>
Date: Sat, 25 Apr 2020 22:30:29 +0800
Subject: [PATCH] =?UTF-8?q?Replace=20player=20patching=20with=20JSON.parse?=
 =?UTF-8?q?()=20hook=20=F0=9F=96=96=F0=9F=96=96=F0=9F=96=96?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/background.js        |  11 --
 src/content.js           | 105 ------------
 src/nflx-player-patch.js | 352 ---------------------------------------
 src/nflxmultisubs.js     |  18 ++
 4 files changed, 18 insertions(+), 468 deletions(-)
 delete mode 100644 src/nflx-player-patch.js

diff --git a/src/background.js b/src/background.js
index fda3701..ccd23f6 100644
--- a/src/background.js
+++ b/src/background.js
@@ -1,17 +1,6 @@
 const kDefaultSettings = require('./default-settings');
 
 
-chrome.webRequest.onBeforeRequest.addListener(details => {
-  console.log(`Denying: ${details.url}`);
-  return { cancel: true, };
-},
-{
-  urls: ['https://assets.nflxext.com/*cadmium-playercore*'],
-  types: ['script'],
-},
-['blocking']);
-
-
 ////////////////////////////////////////////////////////////////////////////////
 
 
diff --git a/src/content.js b/src/content.js
index c43fb16..fe4acd3 100644
--- a/src/content.js
+++ b/src/content.js
@@ -1,9 +1,4 @@
-const acorn = require('acorn');
 const console = require('./console');
-const { patch } = require('./nflx-player-patch');
-
-
-////////////////////////////////////////////////////////////////////////////////
 
 
 // updated when we got `<script src...>` in the observer
@@ -33,108 +28,8 @@ window.addEventListener('load', () => {
 ////////////////////////////////////////////////////////////////////////////////
 
 
-function mutateUrl(url) {
-  const u = new URL(url);
-  const doubleSlashPath = u.pathname.replace(/\//g, '//');
-  const encodedPath = doubleSlashPath.replace('-', '%2d');
-  const port = (uu.port || (/https:/i.test(u.protocol) ? ':443' : ':80'));
-  const mutatedUrl = `${u.protocol}\/\/:@${u.host}${port}${encodedPath}#`;
-  return mutatedUrl;
-}
-
-
-const observer = new MutationObserver(mutations => {
-  mutations.forEach(mutation => {
-    mutation.addedNodes.forEach(node => {
-      if (node.nodeName.toLowerCase() !== 'script') return;
-      if (node.id !== 'player-core-js') return;
-
-      const playerNode = node;
-      let playerUrl = playerNode.getAttribute('src');
-      playerNode.removeAttribute('src');
-      console.log(`Intercepted: ${playerUrl}`);
-
-      // URL looks like "https://assets.nflxext.com/en_us/ffe/player/html/cadmium-playercore-5.0008.727.011.js"
-      origPlayerUrl = playerUrl;
-      let match = /playercore-(\d+\.\d+\.\d+\.\d+)\.js/.exec(origPlayerUrl);
-      if (match) {
-        origPlayerVersion = match[1];
-      }
-
-      const _patchCodeAndLoad = (playerScript) => {
-        const patched = patch(playerScript);
-        const blob = new Blob([patched], { type: 'text/javascript' });
-
-        if (BROWSER === 'chrome') {
-          playerNode.setAttribute('src', URL.createObjectURL(blob));
-          playerNode.addEventListener('load', () => {
-            URL.revokeObjectURL(playerNode.getAttribute('src'));
-          });
-        }
-        else if (BROWSER === 'firefox') {
-          // replacing "src" does not trigger execution in Firefox,
-          // thus we need to replace the <script> node;
-          // fortunately, Netflix player page works well with the replacement
-          const newPlayer = document.createElement('script');
-          newPlayer.setAttribute('id', playerNode.getAttribute('id'));
-          newPlayer.setAttribute('src', URL.createObjectURL(blob));
-          newPlayer.addEventListener('load', () => {
-            URL.revokeObjectURL(newPlayer.getAttribute('src'));
-          });
-          playerNode.replaceWith(newPlayer);
-        }
-      };
-
-      // fetch original player code, and patch it!
-      fetch(playerUrl).then(r => r.text()).then(body => {
-        if ((typeof origPlayerVersion === 'string') &&
-            (body.indexOf(origPlayerVersion) < 0))
-        {
-          // trying to bypass other extensinos :-)
-          // they intercept the request and reply with a local patched code (likely out-dated)
-          console.warn("Warning: the player might be tempered by others -- let's bypass them ^_<");
-
-          const mutatedUrl = mutateUrl(playerUrl);
-          fetch(mutatedUrl).then(r => r.text()).then(body2 => {
-            if (body2.indexOf(origPlayerVersion) < 0) {
-              console.warn('Warning: still got a outdated player, fine :-(');
-              _patchCodeAndLoad(body); // body2 may be more corrupt
-            }
-            else {
-              console.log('Success: got the latest official player, hehe!');
-              _patchCodeAndLoad(body2);
-            }
-          });
-        }
-        else {
-          _patchCodeAndLoad(body);
-        }
-      });
-
-      observer.disconnect();
-
-      // FYI to users who open the developer console
-      if (BROWSER === 'chrome') {
-        console.log(`FYI: "net::ERR_BLOCKED_BY_CLIENT" error is intented`,
-          `(for player code patching)`);
-      }
-      else if (BROWSER === 'firefox') {
-        console.log(`FYI: "Loading failed for the <script>" error is intented`,
-          `(for player code patching)`);
-      }
-    });
-  });
-});
-const options = { subtree: true, childList: true, };
-observer.observe(document, options);
-
-
-////////////////////////////////////////////////////////////////////////////////
-
-
 // Firefox: the target website (our injected agent) cannot connect to extensions
 // directly, thus we need to relay the connection in this content script.
-
 let gMsgPort;
 window.addEventListener('message', evt => {
   if (!evt.data || evt.data.namespace !== 'nflxmultisubs') return;
diff --git a/src/nflx-player-patch.js b/src/nflx-player-patch.js
deleted file mode 100644
index 3bf0ce7..0000000
--- a/src/nflx-player-patch.js
+++ /dev/null
@@ -1,352 +0,0 @@
-const acorn = require('acorn');
-const console = require('./console');
-
-
-// Match sub-tree pattern on the given AST (return on any one match)
-// ast: JavaScript AST generated by `acorn.parse()`
-// pattern: our custom subtree pattern to match with the AST
-// callback: `function(captureId, astNode) { ... }` invoked when `$capture:` is set on pattern
-const findOneOnAcornAst = (ast, pattern, callback) => {
-  const matchSubTree = (astNode, ptnNode, callbackItems) => {
-    if (!astNode || !(astNode instanceof acorn.Node)) return false;
-
-    for (let key in ptnNode) {
-      if (key.startsWith('$')) continue; // our magic attribute
-
-      if (typeof ptnNode[key] === 'string') {
-        if (!astNode[key] || astNode[key] != ptnNode[key]) return false;
-      }
-      else if (ptnNode[key] instanceof Array) {
-        if (!(astNode[key] instanceof Array)) return false;
-        const allFound = ptnNode[key].every(ptnSubNode =>
-          (0 <= astNode[key].findIndex(astSubNode => {
-            //FIXME: we only handle `{ ... }` object on `[ ... ]` for now
-            return matchSubTree(astSubNode, ptnSubNode, callbackItems);
-          }))
-        );
-        if (!allFound) return false;
-      }
-      else if (typeof ptnNode[key] === 'object') {
-        const matched = matchSubTree(astNode[key], ptnNode[key], callbackItems);
-        if (!matched) return false;
-      }
-    }
-
-    const captureId = ptnNode.$capture;
-    if (captureId) {
-      callbackItems.push({captureId, astNode});
-    }
-    return true;
-  };
-
-  let callbackQueue = [];
-  const traverse = (astNode) => {
-    if (!astNode || !(astNode instanceof acorn.Node)) return false;
-
-    let callbackItems = [];
-    if (matchSubTree(astNode, pattern, callbackItems)) {
-      callbackQueue.push(callbackItems);
-      return true;
-    }
-
-    // walk to possible children recursively
-    for (let key in astNode) {
-      if (astNode[key] instanceof Array) {
-        const childNodes = astNode[key];
-        const found = childNodes
-          .filter(childNode => childNode instanceof acorn.Node)
-          .some(childNode => traverse(childNode))
-        if (found) return true;
-      }
-      else if (astNode[key] instanceof acorn.Node) {
-        const childNode = astNode[key];
-        if (traverse(childNode)) return true;
-      }
-    }
-    return false;
-  };
-
-  const found = traverse(ast);
-  if (found && (typeof callback === 'function')) {
-    callbackQueue.forEach(cbItems => {
-      cbItems.forEach(cbItem => callback(cbItem.captureId, cbItem.astNode));
-    });
-  }
-  return found;
-};
-
-
-// -----------------------------------------------------------------------------
-
-
-function injectCallback(script) {
-  const ast = acorn.parse(script);
-
-  // looking for `manifest.textTracks.forEach(function(...){...})`
-  const pattern = {
-    $capture: 'root',
-    type: 'CallExpression',
-    callee: {
-      type: 'MemberExpression',
-      object: {
-        type: 'MemberExpression',
-        object: {
-          $capture: 'manifest',
-          type: 'Identifier',
-        },
-        property: {
-          type: 'Identifier',
-          name: 'textTracks',
-        },
-      },
-      property: {
-        type: 'Identifier',
-        name: 'forEach',
-      },
-    },
-  };
-
-  let injectionOffset, manifestId;
-  const found = findOneOnAcornAst(ast, pattern, (captureId, astNode) => {
-    if (captureId === 'root') injectionOffset = astNode.start;
-    else if (captureId === 'manifest') manifestId = astNode.name;
-  });
-
-  if (!found || injectionOffset === undefined || !manifestId) return null;
-
-  const ourName = 'window.__NflxMultiSubs';
-  const payload = `(${ourName}&&${ourName}.updateManifest(${manifestId}));`;
-  return script.substr(0, injectionOffset) + payload + script.substr(injectionOffset);
-}
-
-
-// -----------------------------------------------------------------------------
-
-
-// add 1080p for Chrome (ref. https://github.com/truedread/netflix-1080p)
-function injectHiResHackChrome(script) {
-  const ast = acorn.parse(script);
-
-  // looking for `uaTestResult = /CrOS/.test(a.userAgent);` and `uaTestResult && this.oo.push(x.V.TH);` in a same function
-  const pattern = {
-    $capture: 'root',
-    type: 'FunctionDeclaration',
-    body: {
-      type: 'BlockStatement',
-      body: [
-        // expression: `uaTestResult = /CrOS/.test(a.userAgent);`
-        {
-          type: 'ExpressionStatement',
-          expression: {
-            type: 'AssignmentExpression',
-            operator: '=',
-            left: {
-              $capture: 'uaTestResult',
-              type: 'Identifier',
-            },
-            right: {
-              type: 'CallExpression',
-              callee: {
-                type: 'MemberExpression',
-                object: {
-                  type: 'Literal',
-                  raw: '/CrOS/',
-                },
-              },
-              arguments: [
-                {
-                  type: 'MemberExpression',
-                  property: {
-                    type: 'Identifier',
-                    name: 'userAgent',
-                  }
-                },
-              ],
-            },
-          },
-        },
-
-        // expression: `uaTestResult2 && this.oo.push(x.V.TH);`
-        {
-          type: 'ExpressionStatement',
-          expression: {
-            type: 'LogicalExpression',
-            left: {
-              $capture: 'uaTestResult2',
-              type: 'Identifier',
-            },
-            operator: '&&',
-            right: {
-              $capture: 'addHiResProfile',
-              type: 'CallExpression',
-              callee: {
-                type: 'MemberExpression',
-                property: {
-                  type: 'Identifier',
-                  name: 'push',
-                },
-              },
-            },
-          },
-        },
-      ],
-    },
-  };
-
-  let uaTestResult, uaTestResult2, injectionOffset, addHiResProfileExp;
-  const found = findOneOnAcornAst(ast, pattern, (captureId, astNode) => {
-    if (captureId === 'uaTestResult')
-      uaTestResult = astNode.name;
-    else if (captureId === 'uaTestResult2')
-      uaTestResult2 = astNode.name;
-    else if (captureId === 'addHiResProfile') {
-      const expLength = (astNode.end - astNode.start);
-      injectionOffset = astNode.end;
-      addHiResProfileExp = script.substr(astNode.start, expLength);
-    }
-  });
-
-  if ((found) && (uaTestResult !== undefined) &&
-      (injectionOffset !== undefined) &&
-      (addHiResProfileExp !== undefined) &&
-      (uaTestResult === uaTestResult2))
-  {
-    const payload = `((!${uaTestResult})&&${addHiResProfileExp});`;
-    if (script[injectionOffset] === ';') {
-      injectionOffset = (injectionOffset + 1);
-    }
-    return script.substr(0, injectionOffset) + payload + script.substr(injectionOffset);
-  }
-  return null;
-}
-
-
-// -----------------------------------------------------------------------------
-
-
-// add 1080p for Firefox
-function injectHiResHackFirefox(script) {
-  const ast = acorn.parse(script);
-
-  // looking for profiles enumeration in a same function, for example:
-  // ...
-  // f.sI = "playready-h264mpl30-dash";
-  // f.dB = "playready-h264mpl31-dash";
-  // f.PV = "playready-h264mpl40-dash";
-  // ...
-  const ptn1 = {
-    type: 'BlockStatement',
-    body: ['playready-h264mpl30-dash',
-           'playready-h264mpl31-dash',
-           'playready-h264mpl40-dash'].map((p, i) => {
-      return {
-        type: 'ExpressionStatement',
-        expression: {
-          type: 'AssignmentExpression',
-          operator: '=',
-          left: {
-            type: 'MemberExpression',
-            property: {
-              $capture: `profile-${i}`,
-              type: 'Identifier',
-            },
-          },
-          right: {
-            type: 'Literal',
-            value: p,
-          },
-        },
-      };
-    }),
-  };
-
-  let prof0, prof1, prof2;
-  let found = findOneOnAcornAst(ast, ptn1, (captureId, astNode) => {
-    if (captureId === 'profile-0') prof0 = astNode.name;
-    else if (captureId === 'profile-1') prof1 = astNode.name;
-    else if (captureId === 'profile-2') prof2 = astNode.name;
-  });
-  if (!found || !prof0 || !prof1 || !prof2) return null;
-
-  // looking for profile set up, for example:
-  // ...
-  // this.sr = [D.V.sI, D.V.dB];
-  // ...
-  const ptn2 = {
-    type: 'AssignmentExpression',
-    left: {
-      type: 'MemberExpression',
-      object: {
-        type: 'ThisExpression',
-      },
-    },
-    right: {
-      $capture: 'profiles-list',
-      type: 'ArrayExpression',
-      elements: [
-        {
-          type: 'MemberExpression',
-          property: {
-            type: 'Identifier',
-            name: prof0,
-          }
-        },
-        {
-          $capture: 'profile-stmt',
-          type: 'MemberExpression',
-          property: {
-            type: 'Identifier',
-            name: prof1,
-          }
-        },
-      ],
-    },
-  };
-
-  let listEnd, profileStmt;
-  found = findOneOnAcornAst(ast, ptn2, (captureId, astNode) => {
-    if (captureId === 'profiles-list') {
-      listEnd = (astNode.end - 1);
-    }
-    else if (captureId === 'profile-stmt') {
-      profileStmt = script.substr(astNode.start, (astNode.end - astNode.start));
-    }
-  });
-  if (!found || !listEnd || !profileStmt) return null;
-
-  return script.substr(0, listEnd) + ',' + profileStmt.replace(prof1, prof2) + script.substr(listEnd);
-}
-
-
-// -----------------------------------------------------------------------------
-
-
-module.exports = {
-  patch: (script) => {
-    let patched = injectCallback(script);
-    if (patched) {
-      script = patched;
-      console.log('Patched: callback');
-    }
-    else {
-      console.error('Error: cannot inject callback');
-    }
-
-
-    if (BROWSER === 'chrome') {
-      patched = injectHiResHackChrome(script);
-    }
-    else if (BROWSER === 'firefox') {
-      patched = injectHiResHackFirefox(script);
-    }
-
-    if (patched) {
-      script = patched;
-      console.log('Patched: hi-res hack');
-    }
-    else {
-      console.error('Error: cannot inject hi-res hack');
-    }
-    return script;
-  }
-};
diff --git a/src/nflxmultisubs.js b/src/nflxmultisubs.js
index dba09d6..ec1d855 100644
--- a/src/nflxmultisubs.js
+++ b/src/nflxmultisubs.js
@@ -5,6 +5,24 @@ const PlaybackRateController = require('./playback-rate-controller');
 
 ////////////////////////////////////////////////////////////////////////////////
 
+// Hook JSON.parse() and attempt to intercept the manifest
+// For cadmium-playercore-6.0022.710.042.js and later
+const hookJsonParseAndAddCallback = function(_window) {
+  const _parse = JSON.parse;
+  _window.JSON.parse = (...args) => {
+      const result = _parse.call(JSON, ...args);
+      if (result && result.result && result.result.movieId) {
+          const movieId = result.result.movieId
+          console.log(`Intercepted manifest ${movieId}`);
+          window.__NflxMultiSubs.updateManifest(result.result);
+      }
+      return result;
+  };
+};
+hookJsonParseAndAddCallback(window);
+
+////////////////////////////////////////////////////////////////////////////////
+
 // global states
 let gSubtitles = [],
   gSubtitleMenu;