utils.py

# -*- coding: utf-8 -*-
# Use ReportLab package to create PDF poster
from reportlab.pdfbase import pdfmetrics
from reportlab.lib.pagesizes import A4
from reportlab.lib.styles import getSampleStyleSheet
from reportlab.lib.units import cm
from reportlab.platypus import (
    SimpleDocTemplate,
    Paragraph,
    Spacer,
    Table,
    TableStyle,
    Image,
    Flowable,
    ListFlowable, 
    ListItem,
)
from reportlab.lib import colors
from reportlab.pdfbase.cidfonts import UnicodeCIDFont

import yt_dlp
import cv2
from PIL import Image as PILImage

import os
import tempfile
import re
import uuid

import pymupdf

'''
# UnicodeCIDfont names
$chs$ = Chinese Simplified (mainland): '$STSong-Light$'
$cht$ = Chinese Traditional (Taiwan): '$MSung-Light$', '$MHei-Medium$'
$kor$ = Korean: '$HYSMyeongJoStd-Medium$','$HYGothic-Medium$'
$jpn$ = Japanese: '$HeiseiMin-W3$', '$HeiseiKakuGo-W5$'
'''

# Configuration
# Register the Chinese font with Reportlab
pdfmetrics.registerFont(UnicodeCIDFont('STSong-Light'))
pdfmetrics.registerFont(UnicodeCIDFont('MSung-Light'))

PAGE_SIZE = A4
MARGIN = 1.0 * cm
COLUMNS = 3  # Now using 3 columns
STYLE = getSampleStyleSheet()
style_body = STYLE["BodyText"]
style_title = STYLE['Title']  
style_title.alignment = 1   # center the title

# Calculate available width for tables
page_width = PAGE_SIZE[0] - 2*MARGIN
col_width = page_width / COLUMNS
img_width = col_width - 1*cm  # Leave some padding
img_height = 5*cm
#==========================================================================
def create_poster(filename, images, lang, summary, url = None):
    print("Output language is:", lang)       
    #generate PDF file
    doc = SimpleDocTemplate(filename, pagesize=PAGE_SIZE,
                           leftMargin=MARGIN, rightMargin=MARGIN,
                           topMargin=MARGIN, bottomMargin=MARGIN)
                            
    story = []
    
    # Define a style with the detected language font
    if lang.lower() == 'chinese':
        style_body.fontName = 'STSong-Light'
        style_title.fontName = 'STSong-Light'
    else:
        style_body.fontName = 'Helvetica'
        style_title.fontName = 'Helvetica-Bold'
   
    # Create table data for detected images
    table_data = []
    list_content = []
    
    with tempfile.TemporaryDirectory() as temp_dir: 
        # Process output summary 
        question = []
        current_answer = []
        answers_part = summary.strip().split("\n")
        title_text = "Summary" # initialize title
        title = Paragraph(f"<b>{title_text}</b>", style_title)

        for line in answers_part: #.split("\n"):
            if re.search("0.", line):  #title line
                clean_line = line.replace("*", "")
                title_text = clean_line.split("0.")
                if len(title_text) > 1:
                    title_text = title_text[1]
                else:
                    title_text = title_text[0]
    
                index = title_text.find(':')
                if index != -1:
                    title_text = title_text[index+1:]
                title = Paragraph(f"<b>{title_text}</b>", style_title) 
                
            elif re.search(r'\d\.', line): 
                # Start of a new question-answer section
                list_content.append(Spacer(1, 0.3*cm))
                if current_answer:
                    list_item = Paragraph(f"<b>{current_answer}</b>", style_body),
                    list_content.append(list_item)
                    current_answer = []
                    
                line_content = line.replace("*", "").split(":")
                question = str(line_content[0]) 
                
                question = Paragraph(f"<b>{question}</b>", style_body)
                list_content.append(question)
                 
                if len(line_content) > 1: #handle same line answer
                    list_item = Paragraph(f"<b>{line_content[1]}</b>", style_body)
                    list_content.append(list_item)
            elif line.strip() and question:
                list_item = Paragraph(f"<b>{line}</b>", style_body)
                list_content.append(list_item) 

            #add last section
            if current_answer:
                list_item = Paragraph(f"<b>{line}</b>", style_body)
                list_content.append(list_item)

        # construct the full list
        markdown_output = ListFlowable(list_content,                                 
                                        bulletType='bullet',            
                                        bulletColor='white', value='circle'                      
                                       ),
        output_list = markdown_output[0]  #workaround for converting tuple to list
        
        # Insert images into a table
        row_cells = []
        for id, image in enumerate(images):    
            face_filename = f'{id}.jpg'
            image_path =  os.path.join(temp_dir, face_filename)
            cv2.imwrite(image_path, image)

            # Load the image back into memory because Image object needs filepath input
            pil_img = PILImage.open(image_path)
                
            # Create cell content
            cell_content = [
                Spacer(1, 0.3*cm),
                Image(image_path, width=img_width, height=img_height),
                Spacer(1, 0.3*cm),
                ]
            row_cells.append(cell_content)
            
        # Add row to table
        table_data.append(row_cells)
        
        # Create table with styling
        tbl = Table(table_data, 
                   colWidths=[col_width]*COLUMNS,
                   rowHeights=img_height+0.5*cm)
    
        tbl.setStyle(TableStyle([
            ('ALIGN', (0,0), (-1,-1), 'CENTER'),
            ('VALIGN', (0,0), (-1,-1), 'CENTER'),
            ('PADDING', (0,0), (-1,-1), 10),
            ('BOX', (0,0), (-1,-1), 0.5, colors.white),
            ('INNERGRID', (0,0), (-1,-1), 0.5, colors.white),
        ]))
                   
        # add flowables
        story.append(title)
        story.append(tbl)
        story.append(Spacer(1,0.3*cm))
        story.append(output_list)
        story.append(Spacer(1,0.5*cm))

        # Clickable video link
        if url:
            link_text = f'<link href="{url}"><font color="{colors.blue}"><u>View Original Video</u></font></link>'
            link_paragraph = Paragraph(link_text, style_body)
            story.append(link_paragraph)
 
        # build a page
        doc.build(story)

    return filename

def generate_unique_filename(extension):
    return f"{uuid.uuid4()}{extension}"

def generate_tmp_filename(basename, extension):
    return f"{basename}{extension}"

def pdf_to_jpg(pdf_path, output_path):
    doc = pymupdf.open(pdf_path)
    page = doc.load_page(0)
    pix = page.get_pixmap()
    pix.save(output_path, "JPEG")

    image = PILImage.open(output_path)
    
    doc.close()

    return image, output_path

def download_youtube_video(url):
    """Downloads a Youtube video using yt-dlp."""
    basename = os.path.basename(url)
    output_path = generate_tmp_filename(basename, ".mp4")
    
    ydl_opts = {
        'outtmpl': output_path,  # Path where the video will be saved
        'format': 'best',        # Download the best quality available
        'cookiefile': 'cookies.txt',  # Path to your cookies file  #JW 20250115
    }
    
    try:
        with yt_dlp.YoutubeDL(ydl_opts) as ydl:          
            ydl.download([url])
        return output_path
    except Exception as e:
        print("load yt_dlp:", e)
        return str(e)