winziprint: add -v and -2 options

winziprint/winziprint.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
+from typing import Union
 import os
 import sys
 import time
@@ -11,23 +12,41 @@ import weasyprint
 import pypdf
 
 
+VERSION = __version__ = '0.1.0'
+
 BATCH_SIZE = 10
 
 
-def convert(input_files: list[str], output_files: str, encoding: str = None, progress: bool = False) -> list[int]:
+def _get_blank_page() -> weasyprint.Page:
+    html = weasyprint.HTML(string='')
+    doc = html.render()
+    blank_page = doc.pages[0]
+    del html
+    del doc
+    return blank_page
+
+
+def convert(input_files: list[str],
+            output_files: str,
+            encoding: str = None,
+            padding: bool = False,
+            progress: bool = False) -> list[int]:
     # it takes roughly 100ms to generate one document
     page_nums = []
     tmp_file_names = []
 
     steps = len(input_files) + len(input_files) // BATCH_SIZE + 1
+    blank_page = _get_blank_page() if padding else None
 
     try:
         for i in range(0, len(input_files), BATCH_SIZE):
             batch = input_files[i:i + BATCH_SIZE]
             documents = []
             for n, file_name in enumerate(batch):
-                html = weasyprint.HTML(file_name, encoding=encoding)
+                html = weasyprint.HTML(filename=file_name, encoding=encoding)
                 doc = html.render()
+                if padding and len(doc.pages) % 2 != 0:
+                    doc.pages.append(blank_page)
                 documents.append(doc)
                 del html
                 if progress:
@@ -60,10 +79,18 @@ def convert(input_files: list[str], output_files: str, encoding: str = None, pro
     return page_nums
 
 
-def _wrapper_convert(args: list[str], encoding: str = None, progress: bool = False) -> None:
+def _wrapper_convert(args: list[str], encoding: str = None, padding: bool = False, progress: bool = False) -> None:
     try:
+        if len(args) < 2:
+            print(f'error: Too few arguments', flush=True)
+            return
+        inputs = args[:-1]
+        output = args[-1]
+        if inputs[0] == '-2':
+            inputs.pop(0)
+            padding = True
         t0 = time.process_time()
-        pages = convert(args[:-1], args[-1], encoding=encoding, progress=progress)
+        pages = convert(inputs, output, encoding=encoding, padding=padding, progress=progress)
         t1 = time.process_time()
         print(f'success: '
               f'{len(args) - 1} documents, '
@@ -79,57 +106,67 @@ def _wrapper_convert(args: list[str], encoding: str = None, progress: bool = Fal
 
 
 def usage() -> None:
-    print(f'usage: {sys.argv[0]} [-h] [-p] [-d DIR] [-e ENCODING] [ - | INPUT [INPUT...] OUTPUT ]\n\n'
+    print(f'usage: {sys.argv[0]} [-h] [-v] [-p] [-2] [-d DIR] [-e ENCODING] [ - | INPUT [INPUT...] OUTPUT ]\n\n'
           'options:\n'
-          ' -h, --help       show this help message and exit\n'
+          ' -h, --help          show this help message and exit\n'
-          ' -d, --directory  set the working directory\n'
+          ' -v, --version       show version and exit\n'
-          ' -e, --encoding   encoding of the input files\n'
+          ' -d, --directory     set the working directory\n'
-          ' -p, --progress   show progress updates\n'
+          ' -e, --encoding      encoding of the input files\n'
+          ' -2, --double-paged  pad documents to an even number of pages\n'
+          ' -p, --progress      show progress updates\n'
           '\n'
-          ' -                use stdin for retrieving input and output file names (semi-colon-seperated)\n'
+          ' -                   use stdin for retrieving input and output file names (semi-colon-seperated)\n'
-          ' INPUT            name of an html input file\n'
+          ' INPUT               name of an html input file\n'
-          ' OUTPUT           name of an pdf output file', file=sys.stderr)
+          ' OUTPUT              name of an pdf output file', file=sys.stderr)
     sys.exit(1)
 
 
-def _get_arg(args: list[str], n1: str, n2: str = None) -> str:
+def version() -> None:
+    print(f'WinziPrint: {__version__}\n'
+          f'WeasyPrint: {weasyprint.__version__}',
+          file=sys.stderr)
+    sys.exit(1)
+
+
+def _get_arg(args: list[str], n1: str, n2: str = None, flag: bool = False) -> Union[None, str, bool]:
     v = None
     for n in [n1] + (n2 and [n2] or []):
-        if n in args:
+        if flag:
-            i = args.index(n)
+            if n in args:
-            if i + 1 >= len(args):
+                v = True
-                usage()
+                args.remove(n)
-            v = args[i + 1]
+        else:
-            args.pop(i)
+            if n in args:
-            args.pop(i)
+                i = args.index(n)
-    return v
+                if i + 1 >= len(args):
+                    usage()
+                v = args[i + 1]
+                args.pop(i)
+                args.pop(i)
+    return v if not flag else v or False
 
 
 def main() -> None:
     args = sys.argv[1:]
     if len(args) == 0 or '-h' in args or '--help' in args:
         usage()
+    elif '-v' in args or '--version' in args:
+        version()
 
     working_dir = _get_arg(args, '-d', '--directory')
     if working_dir:
         os.chdir(working_dir)
     encoding = _get_arg(args, '-e', '--encoding')
-
+    progress = _get_arg(args, '-p', '--progress', flag=True)
-    progress = False
+    double_paged = _get_arg(args, '-2', '--double-paged', flag=True)
-    if '-p' in args:
-        args.remove('-p')
-        progress = True
-    if '--progress' in args:
-        args.remove('--progress')
-        progress = True
 
     if args == ['-']:
         for line in sys.stdin:
-            _wrapper_convert(line.strip().split(';'), encoding=encoding, progress=progress)
+            _wrapper_convert(line.strip().split(';'), encoding=encoding, padding=double_paged, progress=progress)
     elif len(args) < 2:
         usage()
     else:
-        _wrapper_convert(args, encoding=encoding, progress=progress)
+        _wrapper_convert(args, encoding=encoding, padding=double_paged, progress=progress)
 
 
 if __name__ == '__main__':