### Espaço de Tecnologias e Artes - Sesc Avenida Paulista
## Grupo de estudos em Python

### `hackmd.io/@sesc-av-paulista/estudos-em-python-19-agosto`

### Manipulando PDFs

- Fundindo 2 PDFs lado a lado: https://gist.github.com/villares/e902bdbe093ef832f770bdd451cdb03e
- Encolhe PDF (4 páginas por página) https://gist.github.com/villares/e902bdbe093ef832f770bdd451cdb03e
- Fazedor de zines https://gist.github.com/villares/0402a1c9033e6f4baf55554c16d25f4e

- Tirar nome do PDF: https://github.com/villares/anonymize-pdf-annotations

- PyMuPDF https://pymupdf.readthedocs.io/en/latest/

- Zine maker com interface GUI para selecionar arquivo:

"""
Make a PDF A3 zine combining 8 pages from a source PDF

WIP: I'd like to have an option for the 9th page (index=8) to be a poster in the backside or not.
-------------------------------------------------------------------------------
License: GNU GPL V3
(c) 2025 Alexandre Villares

Based on https://github.com/fitz/fitz-Utilities/blob/master/examples/combine-pages/combine.py
(c) 2018 Jorj X. McKie

Dependencies (install!)
------------
PyMuPDF (the fitz engine)
FreeSimpleGUI

Usage
-----
python combine.py input.pdf

|----|----|----|----|
| 0d | 7d | 6d | 5d |
|----|----|----|----|
| 1u | 2u | 3u | 4u |
|----|----|----|----|

|----|----|----|----|
|                   |
|        8s         |
|                   |
|----|----|----|----|

N = page 0-based 
u = normal orientation
d = upside down (rotated 180)
s = big poster (rotated 90)

Notes
-----
(1) Output file is chosen to have A3 landscape pages. Input pages are scaled
    maintaining side proportions.
"""
from pathlib import Path
import fitz
import FreeSimpleGUI as sg

L_FONT = ('Courier', 20)
I_FONT = ('Courier', 16)

# Define the GUI layout
layout = [
    [sg.Text('Input file:', font=L_FONT)],
    [sg.InputText(font=I_FONT), sg.FileBrowse(font=I_FONT)],
    [sg.Button('Create PDF', font=L_FONT),
     sg.Button('CLOSE/EXIT', font=L_FONT)]
]

# Create the GUI window
window = sg.Window('Modify PDF annotations & metadata', layout)

while True:
    # Get the next GUI event
    event, values = window.read()
    # Exit the event loop if the window was closed or the Cancel button was clicked
    if event in (None, 'CLOSE/EXIT'):
        break
    elif event == 'Create PDF' and values:
        input_file = Path(values[0])
        output_file = input_file.parent / (input_file.stem + '_zine.pdf')


        src = fitz.open(input_file)
        doc = fitz.open()  # empty output PDF

        height, width = fitz.paper_size("a3")  # A3 output page format
        # define the 4 rectangles per page
        r0 = fitz.Rect(0, 0, width / 4, height / 2) # top left rect
        r7 = r0 + (r0.width, 0, r0.width, 0)  
        r6 = r7 + (r0.width, 0, r0.width, 0)   
        r5 = r6 + (r0.width, 0, r0.width, 0)    # top right
        r1 = r0 + (0, r0.height, 0, r0.height)  # bottom left
        r2 = r1 + (r0.width, 0, r0.width, 0)
        r3 = r2 + (r0.width, 0, r0.width, 0)
        r4 = r3 + (r0.width, 0, r0.width, 0)# bottom right
        r8 = fitz.Rect(0, 0, width, height)
        # put them in a list
        r_tab = [r0, r1, r2, r3, r4, r5, r6, r7, r8]

        front_and_back = False
        big_poster = True
        poster_offset = 0
        # now copy input pages to output
        for spage in src:          
            if (spage.number - poster_offset) % 8 == 0:  # create new output page
                page = doc.new_page(-1, width=width, height=height)
            # insert input page into the correct rectangle
            r_position = (spage.number - poster_offset) % (9 if big_poster else 8)
            # imposition rotation rule
            rotation = (180 if r_position in (0, 7, 6, 5)
                         else 90 if r_position == 8 else 0) 
            page.show_pdf_page(
                r_tab[r_position],  # select output rect
                src,  # input document
                spage.number,
                rotate=rotation
            )  # input page number
        # by all means, save new file using garbage collection and compression
        doc.save(output_file, garbage=4, deflate=True)
        sg.popup(f'{output_file.name} saved.')