Implement support for references with --open-at

src/calibre/gui2/viewer/main.py

@@ -168,7 +168,8 @@ View an e-book.
         'at the location of the first Table of Contents entry that contains '
         'the string "something". The form toc-href:something will match the '
         'href (internal link destination) of toc nodes. The matching is exact, '
-        'If you want to match a substring, use the form toc-href-contains:something. '))
+        'If you want to match a substring, use the form toc-href-contains:something. '
+        'The form ref:something will use Reference mode references.'))
     a('--continue', default=False, action='store_true', dest='continue_reading',
         help=_('Continue reading at the previously opened book'))
 
@@ -192,7 +193,7 @@ def main(args=sys.argv):
     oat = opts.open_at
     if oat and not (
             oat.startswith('toc:') or oat.startswith('toc-href:') or oat.startswith('toc-href-contains:') or
-            oat.startswith('epubcfi(/') or is_float(oat)):
+            oat.startswith('epubcfi(/') or is_float(oat) or oat.startswith('ref:')):
         raise SystemExit('Not a valid --open-at value: {}'.format(opts.open_at))
 
     listener = None

src/calibre/gui2/viewer/ui.py

@@ -416,6 +416,8 @@ class EbookViewer(MainWindow):
                 initial_position = {'type': 'toc', 'data': initial_toc_node}
             elif open_at.startswith('epubcfi(/'):
                 initial_position = {'type': 'cfi', 'data': open_at}
+            elif open_at.startswith('ref:'):
+                initial_position = {'type': 'ref', 'data': open_at[len('ref:'):]}
             elif is_float(open_at):
                 initial_position = {'type': 'bookpos', 'data': float(open_at)}
         self.web_view.start_book_load(initial_position=initial_position)

src/pyj/read_book/iframe.pyj

@@ -29,7 +29,9 @@ from read_book.paged_mode import (
     scroll_by_page as paged_scroll_by_page, scroll_to_elem,
     scroll_to_fraction as paged_scroll_to_fraction, snap_to_selection
 )
-from read_book.referencing import end_reference_mode, start_reference_mode
+from read_book.referencing import (
+    elem_for_ref, end_reference_mode, start_reference_mode
+)
 from read_book.resources import finalize_resources, unserialize_html
 from read_book.settings import (
     apply_colors, apply_font_size, apply_settings, apply_stylesheet, opts,
@@ -92,6 +94,7 @@ class IframeBoss:
             'initialize':self.initialize,
             'display': self.display,
             'scroll_to_anchor': self.on_scroll_to_anchor,
+            'scroll_to_ref': self.on_scroll_to_ref,
             'scroll_to_frac': self.on_scroll_to_frac,
             'next_screen': self.on_next_screen,
             'change_font_size': self.change_font_size,
@@ -275,6 +278,8 @@ class IframeBoss:
                 self.to_scroll_fraction(ipos.frac)
             elif ipos.type is 'anchor':
                 self.scroll_to_anchor(ipos.anchor)
+            elif ipos.type is 'ref':
+                self.scroll_to_ref(ipos.refnum)
             elif ipos.type is 'cfi':
                 self.jump_to_cfi(ipos.cfi)
             elif ipos.type is 'search':
@@ -466,6 +471,17 @@ class IframeBoss:
         else:
             scroll_viewport.scroll_to(0, 0)
 
+    def scroll_to_ref(self, refnum):
+        refnum = int(refnum)
+        elem = elem_for_ref(refnum)
+        if elem:
+            scroll_to_elem(elem)
+
+    def on_scroll_to_ref(self, data):
+        refnum = data.refnum
+        if refnum?:
+            self.scroll_to_ref(refnum)
+
     def find(self, data, from_load):
         if data.searched_in_spine:
             window.getSelection().removeAllRanges()

src/pyj/read_book/referencing.pyj

@@ -6,6 +6,12 @@ from __python__ import bound_methods, hash_literals
 from read_book.globals import get_boss
 
 
+def elem_for_ref(refnum):
+    refnum = int(refnum)
+    p = document.getElementsByTagName('p')[refnum - 1]
+    return p
+
+
 def on_mouse_over(ev):
     p = this
     if p.dataset.calibreRefNum:

src/pyj/read_book/view.pyj

@@ -655,6 +655,8 @@ class View:
             elif initial_position.type is 'bookpos':
                 navigated = True
                 self.goto_book_position(initial_position.data)
+            elif initial_position.type is 'ref':
+                navigated = self.goto_reference(initial_position.data)
         if navigated:
             self.hide_loading()
         else:
@@ -769,6 +771,20 @@ class View:
             return True
         return False
 
+    def goto_reference(self, reference):
+        if not self.book or not self.book.manifest:
+            return
+        index, refnum = reference.split('.')
+        index, refnum = int(index), int(refnum)
+        chapter_name = self.book.manifest.spine[index]
+        if not chapter_name:
+            return False
+        if self.currently_showing.name is chapter_name:
+            self.iframe_wrapper.send_message('scroll_to_ref', refnum=refnum)
+        else:
+            self.show_name(chapter_name, initial_position={'type':'ref', 'refnum':refnum, 'replace_history':True})
+        return True
+
     def goto_named_destination(self, name, frag):
         if self.currently_showing.name is name:
             self.iframe_wrapper.send_message('scroll_to_anchor', frag=frag)