"""Moteur Recadrage de pages."""

from pypdf import PdfReader, PdfWriter
from .pdf_utils import get_page_size


def crop_pages(input_path, output_path, crop_top=0, crop_bottom=0,
               crop_left=0, crop_right=0, pages=None):
    """Recadrer les pages specifiees.

    crop_top/bottom/left/right : en points, quantite a retirer de chaque cote
    pages : liste d'indices (0-based) des pages a recadrer. None = toutes.
    """
    reader = PdfReader(input_path)
    writer = PdfWriter()

    if pages is None:
        pages = list(range(len(reader.pages)))

    for i, page in enumerate(reader.pages):
        if i in pages:
            w, h = get_page_size(page)
            new_left = float(page.mediabox.left) + crop_left
            new_bottom = float(page.mediabox.bottom) + crop_bottom
            new_right = float(page.mediabox.right) - crop_right
            new_top = float(page.mediabox.top) - crop_top

            # Securite
            if new_right <= new_left or new_top <= new_bottom:
                writer.add_page(page)
                continue

            page.mediabox.lower_left = (new_left, new_bottom)
            page.mediabox.upper_right = (new_right, new_top)
            page.cropbox = page.mediabox
            if hasattr(page, 'trimbox'):
                page.trimbox = page.mediabox

        writer.add_page(page)

    with open(output_path, "wb") as f:
        writer.write(f)
    return output_path