the start so I can revert back

reader.py

@@ -0,0 +1,181 @@
+#!/usr/bin/env python3
+# importing everything from tkinter
+from tkinter import *
+# importing ttk for styling widgets from tkinter
+from tkinter import ttk
+# importing filedialog from tkinter
+from tkinter import filedialog as fd
+# importing os module
+import os
+from pdfviewer import PDFViewer
+
+class PDFReader:
+    # initializing the __init__ / special method
+    def __init__(self, master):
+        # path for the pdf doc
+        self.path = None
+        # state of the pdf doc, open or closed
+        self.fileisopen = None
+        # author of the pdf doc
+        self.author = None
+        # name for the pdf doc
+        self.name = None
+        # the current page for the pdf
+        self.current_page = 0
+        # total number of pages for the pdf doc
+        self.numPages = None
+        # creating the window
+        self.master = master
+        # gives title to the main window
+        self.master.title('PDF Reader')
+        # gives dimensions to main window
+        # self.master.geometry('580x520+440+180')
+        # this disables the minimize/maximize button on the main window
+        self.master.resizable(width = 0, height = 0)
+        # loads the icon and adds it to the main window
+        # self.master.iconbitmap(self.master, 'pdf_file_icon.ico')
+
+        # creating the menu
+        self.menu = Menu(self.master)
+        # adding it to the main window
+        self.master.config(menu=self.menu)
+        # creating a sub menu
+        self.filemenu = Menu(self.menu)
+        # giving the sub menu a label
+        self.menu.add_cascade(label="File", menu=self.filemenu)
+        # adding a two buttons to the sub menus
+        self.filemenu.add_command(label="Open File", command=self.open_file)
+        self.filemenu.add_command(label="Exit", command=self.master.destroy)
+
+        # creating the top frame
+        self.top_frame = ttk.Frame(self.master, width=580, height=460)
+        # placing the frame using inside main window using grid()
+        self.top_frame.grid(row=0, column=0)
+        # the frame will not propagate
+        self.top_frame.grid_propagate(False)
+        # creating the bottom frame
+        self.bottom_frame = ttk.Frame(self.master, width=580, height=50)
+        # placing the frame using inside main window using grid()
+        self.bottom_frame.grid(row=1, column=0)
+        # the frame will not propagate
+        self.bottom_frame.grid_propagate(False)
+
+        # creating a vertical scrollbar
+        self.scrolly = Scrollbar(self.top_frame, orient=VERTICAL)
+        # adding the scrollbar
+        self.scrolly.grid(row=0, column=1, sticky=(N,S))
+        # creating a horizontal scrollbar
+        self.scrollx = Scrollbar(self.top_frame, orient=HORIZONTAL)
+        # adding the scrollbar
+        self.scrollx.grid(row=1, column=0, sticky=(W, E))
+
+        # creating the canvas for display the PDF pages
+        self.output = Canvas(self.top_frame, bg='#ECE8F3', width=560, height=435)
+        # inserting both vertical and horizontal scrollbars to the canvas
+        self.output.configure(yscrollcommand=self.scrolly.set, xscrollcommand=self.scrollx.set)
+        # adding the canvas
+        self.output.grid(row=0, column=0)
+        # configuring the horizontal scrollbar to the canvas
+        self.scrolly.configure(command=self.output.yview)
+        # configuring the vertical scrollbar to the canvas
+        self.scrollx.configure(command=self.output.xview)
+
+        # loading the button icons
+        self.uparrow_icon = PhotoImage(file='uparrow.png')
+        self.downarrow_icon = PhotoImage(file='downarrow.png')
+        # resizing the icons to fit on buttons
+        self.uparrow = self.uparrow_icon.subsample(3, 3)
+        self.downarrow = self.downarrow_icon.subsample(3, 3)
+        # creating an up button with an icon
+        self.upbutton = ttk.Button(self.bottom_frame,
+                                   image=self.uparrow,
+                                   command=self.prev_page)
+        # adding the button
+        self.upbutton.grid(row=0, column=1, padx=(270, 5), pady=8)
+        # creating a down button with an icon
+        self.downbutton = ttk.Button(self.bottom_frame,
+                                     image=self.downarrow,
+                                     command=self.next_page)
+        # adding the button
+        self.downbutton.grid(row=0, column=3, pady=8)
+        # label for displaying page numbers
+        self.page_label = ttk.Label(self.bottom_frame, text='page')
+        # adding the label
+        self.page_label.grid(row=0, column=4, padx=5)
+    # function for opening pdf files
+
+    def open_file(self):
+        # open the file dialog
+        filepath = fd.askopenfilename(title='Select a PDF file', initialdir=os.getcwd(), filetypes=(('PDF', '*.pdf'), ))
+        # checking if the file exists
+        if filepath:
+            # declaring the path
+            self.path = filepath
+            # extracting the pdf file from the path
+            filename = os.path.basename(self.path)
+            # passing the path to PDFViewer
+            self.miner = PDFViewer(self.path)
+            # getting data and numPages
+            data, numPages = self.miner.get_metadata()
+            # setting the current page to 0
+            self.current_page = 0
+            # checking if numPages exists
+            if numPages:
+                # getting the title
+                self.name = data.get('title', filename[:-4])
+                # getting the author
+                self.author = data.get('author', None)
+                self.numPages = numPages
+                # setting fileopen to True
+                self.fileisopen = True
+                # calling the display_page() function
+                self.display_page()
+                # replacing the window title with the PDF document name
+                self.master.title(self.name)
+
+    # the function to display the page
+    def display_page(self):
+        # checking if numPages is less than current_page and if current_page is less than
+        # or equal to 0
+        if 0 <= self.current_page < self.numPages:
+            # getting the page using get_page() function from miner
+            self.img_file = self.miner.get_page(self.current_page)
+            # inserting the page image inside the Canvas
+            self.output.create_image(0, 0, anchor='nw', image=self.img_file)
+            # the variable to be stringified
+            self.stringified_current_page = self.current_page + 1
+            # updating the page label with number of pages
+            self.page_label['text'] = str(self.stringified_current_page) + ' of ' + str(self.numPages)
+            # creating a region for inserting the page inside the Canvas
+            region = self.output.bbox(ALL)
+            # making the region to be scrollable
+            self.output.configure(scrollregion=region)
+
+    # function for displaying next page
+    def next_page(self):
+        # checking if file is open
+        if self.fileisopen:
+            # checking if current_page is less than or equal to numPages-1
+            if self.current_page <= self.numPages - 1:
+                # updating the page with value 1
+                self.current_page += 1
+                # displaying the new page
+                self.display_page()
+
+
+    def prev_page(self):
+        # checking if file is open
+        if self.fileisopen:
+            # checking if current_page is less than or equal to numPages-1
+            if self.current_page >= 0:
+                # updating the page with value 1
+                self.current_page -= 1
+                # displaying the new page
+                self.display_page()
+
+# creating the root window using Tk() class
+root = Tk()
+    # instantiating/creating object app for class PDFViewer
+app = PDFReader(root)
+    # calling the mainloop to run the app infinitely until user closes it
+root.mainloop()