Implement loading of mathjax files

src/calibre/gui2/viewer2/web_view.py

@@ -4,6 +4,7 @@
 
 from __future__ import absolute_import, division, print_function, unicode_literals
 
+import json
 import os
 
 from PyQt5.Qt import (
@@ -24,6 +25,7 @@ from calibre.gui2.webengine import (
     Bridge, RestartingWebEngineView, create_script, from_js, insert_scripts,
     secure_webengine, to_js
 )
+from calibre.ptempfile import PersistentTemporaryDirectory
 from calibre.utils.config import JSONConfig
 
 try:
@@ -61,6 +63,7 @@ class UrlSchemeHandler(QWebEngineUrlSchemeHandler):
 
     def __init__(self, parent=None):
         QWebEngineUrlSchemeHandler.__init__(self, parent)
+        self.mathjax_tdir = self.mathjax_manifest = None
 
     def requestStarted(self, rq):
         if bytes(rq.requestMethod()) != b'GET':
@@ -96,6 +99,19 @@ class UrlSchemeHandler(QWebEngineUrlSchemeHandler):
             metadata = get_data('calibre-book-metadata.json')[0]
             data = b'[' + manifest + b',' + metadata + b']'
             self.send_reply(rq, mime_type, data)
+        elif name.startswith('mathjax/'):
+            if name == 'mathjax/manifest.json':
+                from calibre.srv.books import get_mathjax_manifest
+                if self.mathjax_tdir is None:
+                    self.mathjax_tdir = PersistentTemporaryDirectory(prefix='v2mjx-')
+                    self.mathjax_manifest = json.dumps(get_mathjax_manifest(self.mathjax_tdir)['files'], encoding='utf-8')
+                self.send_reply(rq, 'application/json', self.mathjax_manifest)
+            else:
+                path = os.path.abspath(os.path.join(self.mathjax_tdir, name))
+                if path.startswith(self.mathjax_tdir):
+                    mt = guess_type(name)
+                    with lopen(path, 'rb') as f:
+                        self.send_reply(rq, mt, f.read())
 
     def send_reply(self, rq, mime_type, data):
         if sip.isdeleted(rq):

src/pyj/viewer-main.pyj

@@ -57,8 +57,56 @@ def get_file(book, name, proceed):
     xhr.send()
 
 
+def mathjax_file_received(name, proceed, end_type, xhr, ev):
+    if end_type is 'abort':
+        return
+    if end_type is not 'load':
+        show_error(_('Failed to load MathJax file'), _(
+            'Could not load the file: {} with error: {}').format(name, xhr.error_html))
+        return
+    if not xhr.responseType or xhr.responseType is 'text':
+        result = xhr.responseText
+    else if xhr.responseType is 'blob' or xhr.responseType is 'json':
+        result = xhr.response
+    else:
+        show_error(_('Failed to load MathJax file'), _(
+            'Could not load the file: {} unknown response type: {}').format(name, xhr.responseType))
+        return
+    if name is 'manifest.json':
+        get_mathjax_files.manifest = result
+        get_mathjax_files_stage2.files_to_get = list(Object.keys(result))
+        get_mathjax_files_stage2.file_data = {}
+        get_mathjax_files_stage2(proceed)
+        return
+
+    get_mathjax_files_stage2.file_data[name] = result
+    get_mathjax_files_stage2.files_to_get.remove(name)
+    if not get_mathjax_files_stage2.files_to_get.length:
+        proceed(get_mathjax_files_stage2.file_data)
+
+
+def get_mathjax_manifest(proceed):
+    xhr = ajax('mathjax/manifest.json', mathjax_file_received.bind(None, 'manifest.json', proceed), ok_code=0)
+    xhr.responseType = 'json'
+    xhr.send()
+
+
+def get_mathjax_files_stage2(proceed):
+    if not get_mathjax_files_stage2.files_to_get.length:
+        proceed(get_mathjax_files_stage2.file_data)
+        return
+    for filename in get_mathjax_files_stage2.files_to_get:
+        xhr = ajax(f'mathjax/{filename}', mathjax_file_received.bind(None, filename, proceed), ok_code=0)
+        xhr.responseType = 'blob' if filename.endswith('.woff') else 'text'
+        xhr.send()
+
+
+
 def get_mathjax_files(proceed):
-    pass  # TODO: Implement this
+    if not get_mathjax_files.manifest:
+        get_mathjax_manifest(proceed)
+    else:
+        get_mathjax_files_stage2(proceed)
 
 
 def update_url_state(replace):