Added a script to fixup problems in the MMP PDF.

bin/fixup_mmp_pdf.py

@@ -0,0 +1,142 @@
+#!/usr/bin/env python3
+""" Fixup issues in the MMP eASLRB. """
+
+import os
+import math
+
+from pikepdf import Pdf, Page, OutlineItem, Encryption, make_page_destination
+import click
+
+# ---------------------------------------------------------------------
+
+def fixup_easlrb( fname, output_fname, optimize_web, rotate, log=None ):
+    """Fixup the eASLRB."""
+
+    def log_msg( msg_type, msg, *args, **kwargs ):
+        if not log:
+            return
+        if isinstance( msg, list ):
+            msg = "\n".join( msg )
+        data = kwargs.pop( "data", None )
+        msg = msg.format( *args, **kwargs )
+        log( msg_type, msg, data=data )
+
+    def percentage( curr, total ):
+        return math.floor( 100 * float(curr) / float(total) )
+
+    # NOTE: It would be nice to use the targetes file to get the TOC entries and annotations
+    # to point to the exact point on the page, but figuring out the text associated with each
+    # annotiation is extremely messy (annotations are simply a rectangle on a page, so we need
+    # to figure out which elements lie within that rectangle, and since things are not always
+    # lined up nicely, this is an unreliable process).
+
+    with Pdf.open( fname ) as pdf:
+
+        log_msg( "start", "Loaded PDF: {}".format( fname ), data=[
+            ( "PDF version", pdf.pdf_version ),
+            ( "# pages", len(pdf.pages) ),
+        ] )
+        log_msg( None, "" )
+
+        # fixup bookmarks in the TOC
+        log_msg( "toc", "Fixing up the TOC..." )
+        def walk_toc( items, depth ):
+            for item_no,item in enumerate(items):
+                if item.destination[0].Type != "/Page" or item.destination[1] != "/Fit" \
+                   or item.page_location is not None or item.page_location_kwargs != {}:
+                    log_msg( "toc:warning", "Unexpected TOC item: {}/{}".format( depth, item_no ) )
+                    continue
+                page = Page( item.destination[0] )
+                page_height = page.mediabox[3]
+                bullet = "#" if depth <= 1 else "-"
+                log_msg( "toc:detail", "  {}{} {} => p{}",
+                    depth*"  ", bullet, item.title, 1+page.index
+                )
+                walk_toc( item.children, depth+1 )
+                new_item = OutlineItem( item.title, page.index, "XYZ", top=page_height )
+                new_item.children = item.children
+                new_item.is_closed = True
+                items[ item_no ] = new_item
+        with pdf.open_outline() as outline:
+            walk_toc( outline.root, 0 )
+            # NOTE: The TOC will be updated when we exit the context manager, and can take some time.
+            log_msg( "toc", "Installing the new TOC..." )
+        log_msg( None, "" )
+
+        # fixup up each page
+        log_msg( "annoations", "Fixing up the content..." )
+        for page_no, raw_page in enumerate(pdf.pages):
+            log_msg( "annotations:progress", "- page {}",
+                1+page_no,
+                data = { "percentage": percentage( page_no, len(pdf.pages) ) }
+            )
+            if rotate:
+                # force pages to be landscape (so that we don't get an h-scrollbar in Firefox
+                # when we set the zoom to "fit width").
+                if raw_page.get("Rotate",0) == 0 and raw_page.MediaBox[2] > raw_page.MediaBox[3]:
+                    raw_page.Rotate = 270
+                else:
+                    raw_page.Rotate = 0
+            page = Page( raw_page )
+            page_height = page.mediabox[3]
+            for annot in raw_page.get( "/Annots", [] ):
+                dest = annot.get( "/Dest" )
+                if dest:
+                    page_no = Page( dest[0] ).index
+                    log_msg( "annotations:detail", "  - {} => p{}",
+                        repr(annot.Rect), 1+page_no
+                    )
+                    annot.Dest = make_page_destination( pdf, page_no, "XYZ", top=page_height )
+        log_msg( None, "" )
+
+        # save the updated PDF
+        log_msg( "save", "Saving updated PDF: {}", output_fname )
+        # NOTE: Setting a blank password will encrypt the file, but doesn't require the user to enter a password
+        # when opening the file (but it will be marked as "SECURE" in the UI).
+        enc = Encryption( owner="", user="" )
+        def save_progress( pct ):
+            log_msg( "save:progress", "- Saved {}%...", pct,
+                data = { "percentage": pct }
+            )
+        pdf.save( output_fname, encryption=enc, linearize=optimize_web,
+            progress = save_progress
+        )
+
+        # compare the file sizes
+        old_size = os.path.getsize( fname )
+        new_size = os.path.getsize( output_fname )
+        ratio = round( 100 * float(new_size) / float(old_size) ) - 100
+        if ratio == 0:
+            log_msg( "save", "The updated PDF file is about the same size as the original file." )
+        else:
+            log_msg( "save", "The updated PDF file is about {}% {} than the original file.",
+                abs(ratio), "larger" if ratio > 0 else "smaller"
+            )
+
+# ---------------------------------------------------------------------
+
+@click.command()
+@click.argument( "pdf_file", nargs=1, type=click.Path(exists=True,dir_okay=False) )
+@click.option( "--output","-o", required=True, type=click.Path(dir_okay=False), help="Where to save the fixed-up PDF." )
+@click.option( "--optimize-web", is_flag=True, default=False, help="Optimize for use in a browser (larger file)." )
+@click.option( "--rotate", is_flag=True, default=False, help="Rotate landscape pages." )
+@click.option( "--verbose","-v", is_flag=True, default=False, help="Verbose output." )
+@click.option( "--progress","-p", is_flag=True, default=False, help="Log progress." )
+def main( pdf_file, output, optimize_web, rotate, verbose, progress ):
+    """Fixup the eASLRB."""
+
+    def log_msg( msg_type, msg, data=None ):
+        if not msg_type:
+            msg_type = ""
+        if msg_type.endswith( ":detail" ) and not verbose:
+            return
+        if msg_type.endswith( ":progress" ) and not progress:
+            return
+        print( msg )
+        if msg_type == "start":
+            for k, v in data:
+                print( "- {:<12} {}".format( k+":", v ) )
+    fixup_easlrb( pdf_file, output, optimize_web, rotate, log=log_msg )
+
+if __name__ == "__main__":
+    main() #pylint: disable=no-value-for-parameter