from reportlab.pdfgen import canvas
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont
from PyPDF2 import PdfReader, PdfWriter
from datetime import datetime, timedelta
import random
import os
import uuid

BASE_DIR = os.path.dirname(os.path.abspath(__file__))
FONT_DIR = os.path.join(BASE_DIR, "../assets/fonts")

def generate_octo_pdf(data, template_path, output_path):
    from reportlab.lib.colors import HexColor
    TEMP_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)), "../static/tmp")
    os.makedirs(TEMP_DIR, exist_ok=True)

    packet_path = os.path.join(TEMP_DIR, f"temp_overlay_{uuid.uuid4().hex}.pdf")

    c = canvas.Canvas(packet_path)

    # DejaVuSans
    FONT_DEJAVU_SANS = os.path.join(FONT_DIR, "DejaVuSans.ttf")
    
    pdfmetrics.registerFont(TTFont("DejaVuSans", FONT_DEJAVU_SANS))

    # --- Data ---
    nama_produk = data["nama_produk"]
    nama = data["nama"]
    
    # norek 700633448300, random dimulai dari 7
    norek = '7' + ''.join(random.choices('0123456789', k=11))

    # --- Draw ke PDF ---
    c.setFont("DejaVuSans", 9.5)
    c.setFillColor(HexColor("#000000"))
    
    batas_norek = 690
    kiri = 164
    c.drawString(kiri, batas_norek, norek)      
    c.drawString(kiri, batas_norek - 14, nama_produk)
    c.drawString(kiri, batas_norek - 28, nama)

    c.save()

    background = PdfReader(template_path)
    overlay = PdfReader(packet_path)
    writer = PdfWriter()

    page = background.pages[0]
    page.merge_page(overlay.pages[0])
    writer.add_page(page)

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

    # Bersihkan file sementara
    if os.path.exists(packet_path):
        os.remove(packet_path)