Initial commit — Copydev Imposing Tool

Outil d'imposition PDF desktop (PyQt6) remplacant Quite Imposing Plus. 9 fonctions : livret, n-up, step & repeat, imposition manuelle, jointure pages, pages blanches, numerotation, masquage, fonds perdus. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-03-20 10:54:02 +01:00
commit e3dfd90933
30 changed files with 2364 additions and 0 deletions
--- a/app/engine/booklet.py
+++ b/app/engine/booklet.py
@@ -0,0 +1,196 @@
+"""Moteur de creation de livrets."""
+
+from pypdf import PdfReader, PdfWriter, PageObject, Transformation
+from .pdf_utils import get_page_size, create_blank_page, pad_to_multiple
+import io
+import math
+
+
+def create_booklet(input_path, output_path, binding="saddle_stitch", sheet_size=None,
+                   signature_size=32, alignment="center"):
+    """Creer un livret a partir d'un PDF.
+
+    binding: "continuous", "saddle_stitch", "perfect_bound", "cut_stacks"
+    sheet_size: (largeur, hauteur) en points, ou None pour auto (2x page)
+    signature_size: nombre de pages par cahier (perfect_bound uniquement)
+    alignment: "bottom_left", "center", "pull_center"
+    """
+    reader = PdfReader(input_path)
+
+    if binding == "continuous":
+        return _booklet_continuous(reader, output_path, sheet_size, alignment)
+    elif binding == "saddle_stitch":
+        return _booklet_saddle_stitch(reader, output_path, sheet_size, alignment)
+    elif binding == "perfect_bound":
+        return _booklet_perfect_bound(reader, output_path, sheet_size, signature_size, alignment)
+    elif binding == "cut_stacks":
+        return _booklet_cut_stacks(reader, output_path, sheet_size, alignment)
+
+
+def _get_sheet_size(reader, sheet_size):
+    """Determiner la taille de la feuille."""
+    page_w, page_h = get_page_size(reader.pages[0])
+    if sheet_size:
+        return sheet_size
+    # Auto: feuille = 2x largeur de page
+    return (page_w * 2, page_h)
+
+
+def _place_two_pages(left_page, right_page, sheet_w, sheet_h, page_w, page_h, alignment):
+    """Placer deux pages cote a cote sur une feuille."""
+    sheet = PageObject.create_blank_page(width=sheet_w, height=sheet_h)
+
+    half_w = sheet_w / 2
+
+    if alignment == "center":
+        left_x = (half_w - page_w) / 2
+        right_x = half_w + (half_w - page_w) / 2
+        y = (sheet_h - page_h) / 2
+    elif alignment == "pull_center":
+        left_x = half_w - page_w
+        right_x = half_w
+        y = (sheet_h - page_h) / 2
+    else:  # bottom_left
+        left_x = 0
+        right_x = half_w
+        y = 0
+
+    if left_page:
+        left_copy = PageObject.create_blank_page(width=sheet_w, height=sheet_h)
+        left_copy.merge_page(left_page)
+        left_copy.add_transformation(Transformation().translate(left_x, y))
+        sheet.merge_page(left_copy)
+
+    if right_page:
+        right_copy = PageObject.create_blank_page(width=sheet_w, height=sheet_h)
+        right_copy.merge_page(right_page)
+        right_copy.add_transformation(Transformation().translate(right_x, y))
+        sheet.merge_page(right_copy)
+
+    return sheet
+
+
+def _booklet_continuous(reader, output_path, sheet_size, alignment):
+    """Mode continu: pages 1+2, 3+4, etc."""
+    reader = pad_to_multiple(reader, 2)
+    pages = reader.pages
+    page_w, page_h = get_page_size(pages[0])
+    sheet_w, sheet_h = _get_sheet_size(reader, sheet_size)
+
+    writer = PdfWriter()
+    for i in range(0, len(pages), 2):
+        left = pages[i]
+        right = pages[i + 1] if i + 1 < len(pages) else None
+        sheet = _place_two_pages(left, right, sheet_w, sheet_h, page_w, page_h, alignment)
+        writer.add_page(sheet)
+
+    with open(output_path, "wb") as f:
+        writer.write(f)
+    return output_path
+
+
+def _saddle_stitch_order(num_pages):
+    """Calculer l'ordre des pages pour piqure a cheval.
+
+    Pour N pages (multiple de 4):
+    Feuille 1 recto: page N, page 1
+    Feuille 1 verso: page 2, page N-1
+    Feuille 2 recto: page N-2, page 3
+    etc.
+    """
+    pairs = []
+    n = num_pages
+    for i in range(n // 4):
+        # Recto
+        pairs.append((n - 1 - 2 * i, 2 * i))
+        # Verso
+        pairs.append((2 * i + 1, n - 2 - 2 * i))
+    return pairs
+
+
+def _booklet_saddle_stitch(reader, output_path, sheet_size, alignment):
+    """Piqure a cheval."""
+    reader = pad_to_multiple(reader, 4)
+    pages = reader.pages
+    num_pages = len(pages)
+    page_w, page_h = get_page_size(pages[0])
+    sheet_w, sheet_h = _get_sheet_size(reader, sheet_size)
+
+    pairs = _saddle_stitch_order(num_pages)
+    writer = PdfWriter()
+
+    for left_idx, right_idx in pairs:
+        left = pages[left_idx] if left_idx < num_pages else None
+        right = pages[right_idx] if right_idx < num_pages else None
+        sheet = _place_two_pages(left, right, sheet_w, sheet_h, page_w, page_h, alignment)
+        writer.add_page(sheet)
+
+    with open(output_path, "wb") as f:
+        writer.write(f)
+    return output_path
+
+
+def _booklet_perfect_bound(reader, output_path, sheet_size, signature_size, alignment):
+    """Dos carre colle: plusieurs cahiers de signature_size pages."""
+    reader = pad_to_multiple(reader, 4)
+    pages = reader.pages
+    num_pages = len(pages)
+    page_w, page_h = get_page_size(pages[0])
+    sheet_w, sheet_h = _get_sheet_size(reader, sheet_size)
+
+    writer = PdfWriter()
+
+    # Decouper en signatures
+    for sig_start in range(0, num_pages, signature_size):
+        sig_end = min(sig_start + signature_size, num_pages)
+        sig_pages = list(range(sig_start, sig_end))
+
+        # Padding de la signature
+        while len(sig_pages) % 4 != 0:
+            sig_pages.append(None)
+
+        n = len(sig_pages)
+        for i in range(n // 4):
+            # Recto
+            left_idx = sig_pages[n - 1 - 2 * i]
+            right_idx = sig_pages[2 * i]
+            left = pages[left_idx] if left_idx is not None and left_idx < num_pages else None
+            right = pages[right_idx] if right_idx is not None and right_idx < num_pages else None
+            sheet = _place_two_pages(left, right, sheet_w, sheet_h, page_w, page_h, alignment)
+            writer.add_page(sheet)
+
+            # Verso
+            left_idx = sig_pages[2 * i + 1]
+            right_idx = sig_pages[n - 2 - 2 * i]
+            left = pages[left_idx] if left_idx is not None and left_idx < num_pages else None
+            right = pages[right_idx] if right_idx is not None and right_idx < num_pages else None
+            sheet = _place_two_pages(left, right, sheet_w, sheet_h, page_w, page_h, alignment)
+            writer.add_page(sheet)
+
+    with open(output_path, "wb") as f:
+        writer.write(f)
+    return output_path
+
+
+def _booklet_cut_stacks(reader, output_path, sheet_size, alignment):
+    """Cut stacks: imprimer, couper en deux, empiler."""
+    reader = pad_to_multiple(reader, 4)
+    pages = reader.pages
+    num_pages = len(pages)
+    page_w, page_h = get_page_size(pages[0])
+    sheet_w, sheet_h = _get_sheet_size(reader, sheet_size)
+
+    writer = PdfWriter()
+    half = num_pages // 2
+
+    for i in range(half):
+        top_idx = i
+        bottom_idx = half + i
+        left = pages[top_idx] if top_idx < num_pages else None
+        right = pages[bottom_idx] if bottom_idx < num_pages else None
+        sheet = _place_two_pages(left, right, sheet_w, sheet_h, page_w, page_h, alignment)
+        writer.add_page(sheet)
+
+    with open(output_path, "wb") as f:
+        writer.write(f)
+    return output_path