updated bookletify to automatically merge 2 pages per sheet

bookletify.py

@@ -1,72 +1,50 @@
 #!/usr/bin/env python3
 
 import os
-import sys
-from math import ceil
-from PyPDF2 import PdfReader, PdfWriter
+import argparse
+from PyPDF2 import PageObject, PdfReader, PdfWriter, PaperSize, Transformation
 
 def main():
-    def print_help():
-        print('bookletify')
-        print()
-        print('USAGE')
-        print('    bookletify [OPTIONS] file')
-        print()
-        print('DESCRIPTION')
-        print('    Rearranges the pages of a pdf in order to print it as is (double')
-        print('    sided, flipped on the short edge) so that you can take it, cut  ')
-        print('    in half and close it like you would do with a book. The result  ')
-        print('    will be the original pdf in the correct order, with the size of ')
-        print('    half a page')
-        print('    Especially useful to print pdfs to A5 size on A4 paper')
-        print()
-        print('OPTIONS')
-        print('    -h    print help')
-        print('    -q    do not print anything to stdout')
-
-    def parse_argv():
-        opts = {
-            "h": False,
-            "q": False,
-        }
-        filename = None
-
-        if len(sys.argv) < 2:
-            opts["h"] = True
-
-        for arg in sys.argv[1:]:
-            if arg.startswith('-'):
-                for opt in opts:
-                    if opt in arg:
-                        opts[opt] = True
-            elif not filename:
-                filename = arg
-
-        return (opts, filename)
-
-    def info(text = '', end='\n'):
-        if not opts["q"]:
-            print(text, end=end)
-
-    def prog(curr, max_val):
-        # Overrides the current terminal line with a progressbar filled at curr/max_val
-        perc = float(curr) / float(max_val)
-        remaining = f'{curr:{len(str(max_val))}d}/{max_val}'
-        (cols, _) = os.get_terminal_size()
-        max_width = cols - len(remaining) - 3
-
-        size = min(max_width, max_val, 80)
-        bar = int(perc * size)
-
-        end = '\n' if curr == max_val else ''
-        info("\r|" + ("\u2588" * bar) + "_" * (size - bar) + "| " + remaining, end)
-
-
-    (opts, input_name) = parse_argv()
-    if opts["h"] or not input_name:
-        print_help()
-        exit(0)
-
+    PROGRAM_NAME="bookletify"
+    DESCRIPTION = """Rearranges the pages of a pdf in order to print it as is,
+        so that you can take it, cut it in half and close it like you would
+        with a book. The result will be the original pdf in the correct order,
+        with the size of half a page. Especially useful to print pdfs to A5
+        size on A4 paper"""
+    
+    parser = argparse.ArgumentParser(
+            prog=PROGRAM_NAME,
+            description=DESCRIPTION
+        )
+    
+    parser.add_argument('filename')
+    parser.add_argument('-q', '--quiet',
+                        action='store_true',
+                        help='suppress stdout')
+    parser.add_argument('-s', '--size',
+                        action='store',
+                        choices=['A0', 'A1', 'A2', 'A3', 'A4', 'A5', 'A6', 'A7', 'A8', 'C4'],
+                        default='A4',
+                        metavar='SIZE',
+                        help="""set final paper size. Possible values: 'A0',
+                            ..., 'A8' or 'C4'. Default value is 'A4'""")
+
+    parser.add_argument('-b', '--binding-margin',
+                        default=10,
+                        type=float,
+                        metavar='MARGIN',
+                        help="""internal margin for the binding, expressed in
+                            millimeters. Default value is 10""")
+    
+    args = parser.parse_args()
+
+    info = lambda text='', end='\n': print(text, end=end)
+    if args.quiet:
+        info = lambda text='', end='\n': None
+
+    prog = lambda curr, max: info(f"\r{curr} / {max}", '\n' if curr == max else '')
+
+    input_name = args.filename
     if not os.path.isfile(input_name):
         print(f'file {input_name} does not exist')
         exit(1)
@@ -76,46 +54,59 @@ def main():
         output_name = f'{input_name[0:-4]}-rearranged.pdf'
     
 
+    fullwidth = getattr(PaperSize, args.size).width
+    fullheight = getattr(PaperSize, args.size).height
+    smallwidth = fullheight / 2
+    smallheight = fullwidth
+    # Convert mm to pixels at 72 dpi
+    bindingwidth = args.binding_margin * 72 / float(25.4)
+    smallblank = PageObject.create_blank_page(width=smallwidth - bindingwidth, height=smallheight)
+    
     # Read the input
     reader = PdfReader(input_name)
-    
-    # Write the result to a file
-    middle = PdfWriter()
-    info("Loading...")
     n = len(reader.pages)
-    # Set m as the smallest multiple of 4 bigger or equal to n
-    m = ceil(n / 4) * 4
+    pages = []
 
+    info("Reading...")
     for i in range(n):
-        prog(i, m)
-        middle.add_page(reader.pages[i])
+        prog(i, n)
+        pages.append(reader.pages[i])
+    prog(n,n)
 
-    for i in range(m - n):
-        prog(n + i, m)
-        middle.add_blank_page()
+    while(len(pages) % 4 != 0):
+        pages.append(smallblank)
     
-    prog(m, m)
 
     output = PdfWriter()
-    info()
-    info("Rearranging...")
-    for i in range(int(m / 4)):
-        mod = i * 2
-        prog(i * 4, m)
-        output.add_page(middle.pages[m - 1 - mod])
-        prog(i * 4 + 1, m)
-        output.add_page(middle.pages[mod])
-        prog(i * 4 + 2, m)
-        output.add_page(middle.pages[1 + mod])
-        prog(i * 4 + 3, m)
-        output.add_page(middle.pages[m - 2 - mod])
-    prog(m, m)
-    
-    info()
-    info("Saving...")
+    info("\nRearranging...")
+
+    def merge_srt_page(base, over, angle, tx, ty):
+        sx = float(smallwidth - bindingwidth) / float(over.mediabox.width)
+        sy = float(smallheight) / float(over.mediabox.height)
+        t = Transformation().scale(sx, sy).rotate(angle). translate(tx, ty)
+        over.add_transformation(t)
+        base.merge_page(over)
+
+    m = len(pages)
+    for i in range(int(m / 2)):
+        prog(i, int(m / 2))
+        new_page = PageObject.create_blank_page(width=fullwidth, height=fullheight)
+        if i % 2 == 0:
+            merge_srt_page(new_page, pages[m - 1 - i], -90, 0, fullheight)
+            merge_srt_page(new_page, pages[i], - 90, 0, smallwidth - bindingwidth)
+            pass
+        else:
+            merge_srt_page(new_page, pages[m - 1 - i], 90, smallheight, smallwidth + bindingwidth)
+            merge_srt_page(new_page, pages[i], 90, smallheight, 0)
+
+        output.add_page(new_page)
+    prog(int(m/2), int(m/2))
+
+    info("\nSaving...")
     output.write(output_name)
-    info("Done!")
-    info()
+    info("\nDone!")
 
 if __name__ == "__main__":
     main()
+
+