"""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, per_page_settings=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.
    per_page_settings : dict {page_index: {"crop_top", "crop_bottom", "crop_left", "crop_right"}}
                        Si fourni, applique des reglages differents par page.
    """
    reader = PdfReader(input_path)
    writer = PdfWriter()

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

    for i, page in enumerate(reader.pages):
        # Verifier si on a des reglages specifiques pour cette page
        if per_page_settings and i in per_page_settings:
            ps = per_page_settings[i]
            ct = ps.get("crop_top", 0)
            cb = ps.get("crop_bottom", 0)
            cl = ps.get("crop_left", 0)
            cr = ps.get("crop_right", 0)
        elif pages is not None and i in pages:
            ct, cb, cl, cr = crop_top, crop_bottom, crop_left, crop_right
        else:
            writer.add_page(page)
            continue

        w, h = get_page_size(page)
        new_left = float(page.mediabox.left) + cl
        new_bottom = float(page.mediabox.bottom) + cb
        new_right = float(page.mediabox.right) - cr
        new_top = float(page.mediabox.top) - ct

        # 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