import os
from fpdf import FPDF
import config

def generate_uplatnica(order_id: int, payer_name: str, payer_address: str, amount: float) -> str:
    """
    Generate a simple PDF 'Nalog za uplatu' (Uplatnica) for Montenegro.
    Returns the absolute path to the generated PDF.
    """
    pdf = FPDF(orientation='L', unit='mm', format=(100, 210))
    pdf.add_page()
    
    # We will just use the default Helvetica or Arial
    pdf.set_font("helvetica", 'B', 12)
    
    # Draw simple border
    pdf.rect(5, 5, 200, 90)
    
    # Title
    pdf.set_y(10)
    pdf.set_font("helvetica", 'B', 14)
    pdf.cell(0, 10, "NALOG ZA UPLATU", align="C")
    
    pdf.set_font("helvetica", '', 10)
    
    # Payer Info (Uplatilac)
    pdf.set_xy(10, 25)
    pdf.cell(40, 5, "UPLATILAC:")
    pdf.set_xy(10, 30)
    pdf.set_font("helvetica", 'B', 10)
    pdf.multi_cell(80, 5, f"{payer_name}\n{payer_address}")
    pdf.set_font("helvetica", '', 10)
    
    # Purpose (Svrha uplate)
    pdf.set_xy(10, 50)
    pdf.cell(40, 5, "SVRHA UPLATE:")
    pdf.set_xy(10, 55)
    pdf.set_font("helvetica", 'B', 10)
    pdf.multi_cell(80, 5, f"Placanje za 3D stampu - Narudzba #{order_id}")
    pdf.set_font("helvetica", '', 10)
    
    # Recipient (Primalac)
    pdf.set_xy(10, 75)
    pdf.cell(40, 5, "PRIMALAC:")
    pdf.set_xy(10, 80)
    pdf.set_font("helvetica", 'B', 10)
    pdf.multi_cell(80, 5, config.COMPANY_NAME)
    pdf.set_font("helvetica", '', 10)
    
    # Right column
    # Amount
    pdf.set_xy(100, 25)
    pdf.cell(40, 5, "IZNOS (EUR):")
    pdf.set_xy(140, 23)
    pdf.set_font("helvetica", 'B', 14)
    pdf.cell(40, 8, f"={amount:.2f}", border=1, align="C")
    pdf.set_font("helvetica", '', 10)
    
    # Account
    pdf.set_xy(100, 40)
    pdf.cell(40, 5, "RACUN PRIMAOCA:")
    pdf.set_xy(140, 38)
    pdf.set_font("helvetica", 'B', 12)
    pdf.cell(60, 8, config.ZIRO_RACUN, border=1, align="C")
    pdf.set_font("helvetica", '', 10)
    
    # Reference
    pdf.set_xy(100, 55)
    pdf.cell(40, 5, "POZIV NA BROJ:")
    pdf.set_xy(140, 53)
    pdf.set_font("helvetica", 'B', 12)
    pdf.cell(60, 8, str(order_id), border=1, align="C")
    
    # Save file
    pdf_dir = os.path.join(config.UPLOAD_DIR, "invoices")
    if not os.path.exists(pdf_dir):
        os.makedirs(pdf_dir)
        
    filename = f"uplatnica_order_{order_id}.pdf"
    filepath = os.path.join(pdf_dir, filename)
    pdf.output(filepath)
    
    return os.path.join("uploads", "invoices", filename).replace("\\", "/")