from reportlab.lib.pagesizes import A4
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.units import cm, mm
from reportlab.lib.colors import HexColor
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table,
    TableStyle, Image, PageBreak
)
from reportlab.lib import colors

def generate_report(output_path, data):
    doc = SimpleDocTemplate(
        output_path,
        pagesize=A4,
        topMargin=2.5*cm,
        bottomMargin=2.5*cm,
        leftMargin=2.5*cm,
        rightMargin=2.5*cm,
    )

    styles = getSampleStyleSheet()
    styles.add(ParagraphStyle(
        name='CustomTitle',
        parent=styles['Title'],
        fontSize=24,
        textColor=HexColor('#2F5496'),
        spaceAfter=20,
    ))

    story = []

    # Title
    story.append(Paragraph(data['title'], styles['CustomTitle']))
    story.append(Spacer(1, 12))

    # Body text
    story.append(Paragraph(data['body'], styles['Normal']))
    story.append(Spacer(1, 20))

    # Table
    table_data = [['Name', 'Value', 'Status']]
    for row in data['rows']:
        table_data.append([row['name'], row['value'], row['status']])

    table = Table(table_data, colWidths=[6*cm, 4*cm, 4*cm])
    table.setStyle(TableStyle([
        ('BACKGROUND', (0, 0), (-1, 0), HexColor('#2F5496')),
        ('TEXTCOLOR', (0, 0), (-1, 0), colors.white),
        ('FONTNAME', (0, 0), (-1, 0), 'Helvetica-Bold'),
        ('FONTSIZE', (0, 0), (-1, 0), 11),
        ('ALIGN', (0, 0), (-1, -1), 'CENTER'),
        ('GRID', (0, 0), (-1, -1), 0.5, colors.grey),
        ('ROWBACKGROUNDS', (0, 1), (-1, -1), [colors.white, HexColor('#F0F4FA')]),
        ('TOPPADDING', (0, 0), (-1, -1), 8),
        ('BOTTOMPADDING', (0, 0), (-1, -1), 8),
    ]))
    story.append(table)

    doc.build(story)

from reportlab.platypus import BaseDocTemplate, Frame, PageTemplate
from datetime import datetime

def add_header_footer(canvas, doc):
    canvas.saveState()
    # Header
    canvas.setFont('Helvetica', 9)
    canvas.setFillColor(HexColor('#888888'))
    canvas.drawString(2.5*cm, A4[1] - 1.5*cm, 'Company Name — Confidential')
    canvas.drawRightString(A4[0] - 2.5*cm, A4[1] - 1.5*cm, f'Page {doc.page}')
    # Footer
    canvas.drawCentredString(A4[0]/2, 1.5*cm, f'Generated on {datetime.now():%Y-%m-%d}')
    canvas.restoreState()

doc = BaseDocTemplate(output_path, pagesize=A4)
frame = Frame(2.5*cm, 2.5*cm, A4[0]-5*cm, A4[1]-5*cm)
doc.addPageTemplates([PageTemplate(id='main', frames=[frame], onPage=add_header_footer)])

import pdfplumber

with pdfplumber.open('document.pdf') as pdf:
    # Extract text from all pages
    full_text = ''
    for page in pdf.pages:
        full_text += page.extract_text() + '\n'

    # Extract tables
    for page in pdf.pages:
        tables = page.extract_tables()
        for table in tables:
            for row in table:
                print(row)

    # Extract text from specific area
    page = pdf.pages[0]
    bbox = (50, 100, 400, 300)  # (x0, top, x1, bottom)
    cropped = page.within_bbox(bbox)
    text = cropped.extract_text()

table_settings = {
    "vertical_strategy": "lines",    # or "text", "explicit"
    "horizontal_strategy": "lines",
    "snap_tolerance": 3,
    "join_tolerance": 3,
    "edge_min_length": 3,
    "min_words_vertical": 3,
    "min_words_horizontal": 1,
}

tables = page.extract_tables(table_settings)

from pypdf import PdfReader, PdfWriter

reader = PdfReader('form.pdf')
writer = PdfWriter()
writer.append(reader)

# Fill form fields
writer.update_page_form_field_values(
    writer.pages[0],
    {
        'full_name': 'Alice Johnson',
        'email': 'alice@example.com',
        'date': '2025-03-15',
        'agree_terms': '/Yes',  # Checkbox
    },
    auto_regenerate=False,
)

with open('filled_form.pdf', 'wb') as f:
    writer.write(f)

from pdf2image import convert_from_path
import pytesseract

def ocr_pdf(pdf_path, language='eng'):
    images = convert_from_path(pdf_path, dpi=300)
    full_text = ''
    for i, image in enumerate(images):
        text = pytesseract.image_to_string(image, lang=language)
        full_text += f'\n--- Page {i+1} ---\n{text}'
    return full_text

# For better accuracy with specific layouts:
def ocr_with_config(image):
    custom_config = r'--oem 3 --psm 6'  # LSTM engine, assume uniform block
    return pytesseract.image_to_string(image, config=custom_config)

from pypdf import PdfReader, PdfWriter

# Merge multiple PDFs
def merge_pdfs(input_paths, output_path):
    writer = PdfWriter()
    for path in input_paths:
        reader = PdfReader(path)
        for page in reader.pages:
            writer.add_page(page)
    with open(output_path, 'wb') as f:
        writer.write(f)

# Split PDF by page ranges
def split_pdf(input_path, ranges, output_dir):
    reader = PdfReader(input_path)
    for i, (start, end) in enumerate(ranges):
        writer = PdfWriter()
        for page_num in range(start - 1, min(end, len(reader.pages))):
            writer.add_page(reader.pages[page_num])
        with open(f'{output_dir}/part_{i+1}.pdf', 'wb') as f:
            writer.write(f)

# Extract specific pages
def extract_pages(input_path, page_numbers, output_path):
    reader = PdfReader(input_path)
    writer = PdfWriter()
    for num in page_numbers:
        writer.add_page(reader.pages[num - 1])
    with open(output_path, 'wb') as f:
        writer.write(f)

from pypdf import PdfReader, PdfWriter
from reportlab.pdfgen import canvas as rl_canvas
from reportlab.lib.pagesizes import A4
from io import BytesIO

def create_watermark(text, opacity=0.1):
    buffer = BytesIO()
    c = rl_canvas.Canvas(buffer, pagesize=A4)
    c.setFillAlpha(opacity)
    c.setFont('Helvetica-Bold', 60)
    c.setFillColorRGB(0.5, 0.5, 0.5)
    c.translate(A4[0]/2, A4[1]/2)
    c.rotate(45)
    c.drawCentredString(0, 0, text)
    c.save()
    buffer.seek(0)
    return PdfReader(buffer)

def apply_watermark(input_path, output_path, watermark_text):
    watermark = create_watermark(watermark_text)
    reader = PdfReader(input_path)
    writer = PdfWriter()

    for page in reader.pages:
        page.merge_page(watermark.pages[0])
        writer.add_page(page)

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

from pypdf import PdfReader, PdfWriter

# Read metadata
reader = PdfReader('document.pdf')
info = reader.metadata
print(f'Title: {info.title}')
print(f'Author: {info.author}')
print(f'Pages: {len(reader.pages)}')

# Write metadata
writer = PdfWriter()
writer.append(reader)
writer.add_metadata({
    '/Title': 'Updated Title',
    '/Author': 'Author Name',
    '/Subject': 'Document Subject',
    '/Creator': 'My Application',
})
with open('updated.pdf', 'wb') as f:
    writer.write(f)