Adding PDF Split application

Author: chris1610

code/pdf_split.py

@@ -0,0 +1,119 @@
+from appJar import gui
+from PyPDF2 import PdfFileWriter, PdfFileReader
+from pathlib import Path
+
+# Define all the functions needed to process the files
+
+
+def split_pages(input_file, page_range, out_file):
+    """ Take a pdf file and copy a range of pages into a new pdf file
+
+    Args:
+        input_file: The source PDF file
+        page_range: A string containing a range of pages to copy: 1-3,4
+        out_file: File name for the destination PDF
+    """
+    output = PdfFileWriter()
+    input_pdf = PdfFileReader(open(input_file, "rb"))
+    output_file = open(out_file, "wb")
+
+    # https://stackoverflow.com/questions/5704931/parse-string-of-integer-sets-with-intervals-to-list
+    page_ranges = (x.split("-") for x in page_range.split(","))
+    range_list = [i for r in page_ranges for i in range(int(r[0]), int(r[-1]) + 1)]
+
+    for p in range_list:
+        # Need to subtract 1 because pages are 0 indexed
+        try:
+            output.addPage(input_pdf.getPage(p - 1))
+        except IndexError:
+            # Alert the user and stop adding pages
+            app.infoBox("Info", "Range exceeded number of pages in input.\nFile will still be saved.")
+            break
+    output.write(output_file)
+
+    if(app.questionBox("File Save", "Output PDF saved. Do you want to quit?")):
+        app.stop()
+
+
+def validate_inputs(input_file, output_dir, range, file_name):
+    """ Verify that the input values provided by the user are valid
+
+    Args:
+        input_file: The source PDF file
+        output_dir: Directory to store the completed file
+        range: File A string containing a range of pages to copy: 1-3,4
+        file_name: Output name for the resulting PDF
+
+    Returns:
+        True if error and False otherwise
+        List of error messages
+    """
+    errors = False
+    error_msgs = []
+
+    # Make sure a PDF is selected
+    if Path(input_file).suffix.upper() != ".PDF":
+        errors = True
+        error_msgs.append("Please select a PDF input file")
+
+    # Make sure a range is selected
+    if len(range) < 1:
+        errors = True
+        error_msgs.append("Please enter a valid page range")
+
+    # Check for a valid directory
+    if not(Path(output_dir)).exists():
+        errors = True
+        error_msgs.append("Please Select a valid output directory")
+
+    # Check for a file name
+    if len(file_name) < 1:
+        errors = True
+        error_msgs.append("Please enter a file name")
+
+    return(errors, error_msgs)
+
+
+def press(button):
+    """ Process a button press
+
+    Args:
+        button: The name of the button. Either Process of Quit
+    """
+    if button == "Process":
+        src_file = app.getEntry("Input_File")
+        dest_dir = app.getEntry("Output_Directory")
+        page_range = app.getEntry("Page_Ranges")
+        out_file = app.getEntry("Output_name")
+        errors, error_msg = validate_inputs(src_file, dest_dir, page_range, out_file)
+        if errors:
+            app.errorBox("Error", "\n".join(error_msg), parent=None)
+        else:
+            split_pages(src_file, page_range, Path(dest_dir, out_file))
+    else:
+        app.stop()
+
+# Create the GUI Window
+app = gui("PDF Splitter", useTtk=True)
+app.setTtkTheme("clam")
+print(app.getTtkThemes())
+app.setSize(500, 200)
+
+# Add the interactive components
+app.addLabel("Choose Source PDF File")
+app.addFileEntry("Input_File")
+
+app.addLabel("Select Output Directory")
+app.addDirectoryEntry("Output_Directory")
+
+app.addLabel("Output file name")
+app.addEntry("Output_name")
+
+app.addLabel("Page Ranges: 1,3,4-10")
+app.addEntry("Page_Ranges")
+
+# link the buttons to the function called press
+app.addButtons(["Process", "Quit"], press)
+
+# start the GUI
+app.go()