app.py

import os
import zipfile
import gradio as gr
import pandas as pd
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import inch
import barcode
from barcode.writer import ImageWriter

# Directories for generated files
LABELS_DIR = "labels"
BARCODES_DIR = "barcodes"
os.makedirs(LABELS_DIR, exist_ok=True)
os.makedirs(BARCODES_DIR, exist_ok=True)

# Required CSV/Excel columns
REQUIRED_COLUMNS = [
    "Order ID", "Order Date", "Shipper Name", "Shipper Address", "Shipper Phone",
    "Receiver Name", "Receiver Address", "Receiver Phone", "Package Weight (kg)",
    "Shipping Method", "Tracking Number", "Estimated Delivery Date"
]

###############################################################################
# 1) Draw the static collage (top portion) for a 4x6 USPS label
###############################################################################
def draw_label_collage(c, width, height):
    """
    Draws the top portion: big 'F', USPS text, placeholder QR code,
    'USPS FIRST-CLASS PKG' title, plus a top horizontal line.
    """
    # Big "F" near top-left
    c.setFont("Helvetica-Bold", 80)
    c.drawString(15, height - 85, "F")

    # USPS postage info block (small text under "F")
    c.setFont("Helvetica", 6)
    c.drawString(70, height - 20, "US POSTAGE AND FEES PAID")
    c.drawString(70, height - 30, "Apr 12 2018")
    c.drawString(70, height - 40, "Mailed from ZIP 77024")
    c.drawString(70, height - 50, "First-Class Pkg Svc")
    c.drawString(70, height - 60, "CommercialBasePrice")

    # Placeholder for QR code in top-right
    c.setFont("Helvetica", 6)
    c.drawString(width - 50, height - 20, "QR CODE")

    # "USPS FIRST-CLASS PKG" in bold, centered near top
    c.setFont("Helvetica-Bold", 14)
    c.drawCentredString(width / 2, height - 110, "USPS FIRST-CLASS PKG")

    # Horizontal line across the label, just below the header
    c.setLineWidth(1)
    c.line(15, height - 115, width - 15, height - 115)

###############################################################################
# 2) Overlay dynamic text + horizontal lines to mimic the sample layout
###############################################################################
def draw_label_text(c, row, width, height):
    """
    Places:
    - Warehouse & Order info, then a horizontal line
    - Recipient address, then another line
    - "USPS TRACKING #" heading, then another line
    - Tracking number below that line
    """
    # Convert row to local variables (with fallback)
    order_id       = row.get("Order ID", "")
    order_date     = row.get("Order Date", "")
    shipper_name   = row.get("Shipper Name", "")
    shipper_addr   = row.get("Shipper Address", "")
    shipper_phone  = row.get("Shipper Phone", "")
    receiver_name  = row.get("Receiver Name", "")
    receiver_addr  = row.get("Receiver Address", "")
    receiver_phone = row.get("Receiver Phone", "")
    weight         = row.get("Package Weight (kg)", "")
    ship_method    = row.get("Shipping Method", "")
    tracking_num   = row.get("Tracking Number", "")
    eta_date       = row.get("Estimated Delivery Date", "")

    # We'll start below the top line from the collage
    top_line_y = height - 115

    ############################
    # Warehouse + Order Info
    ############################
    # Left: Warehouse lines
    c.setFont("Helvetica-Bold", 9)
    c.drawString(15, top_line_y - 15, shipper_name or "WAREHOUSE 2")
    c.setFont("Helvetica", 9)
    c.drawString(15, top_line_y - 30, shipper_addr or "11919 WINK RD")
    c.drawString(15, top_line_y - 45, f"{shipper_phone}" or "HOUSTON TX 77024-7134")

    # Right: "Order: 286"
    c.setFont("Helvetica", 9)
    c.drawRightString(width - 15, top_line_y - 15, f"Order: {order_id}")
    c.drawRightString(width - 15, top_line_y - 30, f"Date: {order_date}")

    # Horizontal line under Warehouse/Order block
    warehouse_line_y = top_line_y - 60
    c.line(15, warehouse_line_y, width - 15, warehouse_line_y)

    ############################
    # Recipient Block
    ############################
    # Bold name, address, phone
    c.setFont("Helvetica-Bold", 11)
    c.drawString(15, warehouse_line_y - 15, receiver_name)
    c.setFont("Helvetica", 9)
    c.drawString(15, warehouse_line_y - 30, receiver_addr)
    c.drawString(15, warehouse_line_y - 45, f"Phone: {receiver_phone}")

    # Possibly show shipping details to the right
    c.setFont("Helvetica-Bold", 9)
    c.drawRightString(width - 15, warehouse_line_y - 15, f"Weight: {weight} kg")
    c.drawRightString(width - 15, warehouse_line_y - 30, f"Method: {ship_method}")
    c.drawRightString(width - 15, warehouse_line_y - 45, f"ETA: {eta_date}")

    # Another line below the recipient block
    recipient_line_y = warehouse_line_y - 60
    c.line(15, recipient_line_y, width - 15, recipient_line_y)

    ############################
    # USPS TRACKING #
    ############################
    # Place "USPS TRACKING #" in bold, centered
    c.setFont("Helvetica-Bold", 12)
    c.drawCentredString(width / 2, recipient_line_y - 20, "USPS TRACKING #")

    # Another line under "USPS TRACKING #"
    tracking_line_y = recipient_line_y - 35
    c.line(15, tracking_line_y, width - 15, tracking_line_y)

    # Tracking number below that line, centered
    c.setFont("Helvetica-Bold", 10)
    c.drawCentredString(width / 2, tracking_line_y - 20, tracking_num)

###############################################################################
# 3) Create the 4x6 USPS-style label
###############################################################################
def create_usps_label(row, index=1):
    """
    1) Generate a Code128 barcode from 'Tracking Number'
    2) Draw collage
    3) Draw dynamic text & lines
    4) Place barcode near the bottom
    """
    # Barcode
    tracking_number = row.get("Tracking Number", "0000000000")
    barcode_filename = os.path.join(BARCODES_DIR, f"barcode_{index}.png")
    code128 = barcode.get_barcode_class("code128")
    code128_obj = code128(tracking_number, writer=ImageWriter())
    code128_obj.save(barcode_filename)

    # 4x6 inches
    width, height = 4 * inch, 6 * inch
    label_filename = os.path.join(LABELS_DIR, f"label_{index}.pdf")
    c = canvas.Canvas(label_filename, pagesize=(width, height))

    # Draw the collage
    draw_label_collage(c, width, height)
    # Overlay text & lines
    draw_label_text(c, row, width, height)

    # Place barcode near bottom, centered horizontally
    if os.path.exists(barcode_filename):
        barcode_w = 3 * inch
        barcode_h = 0.8 * inch
        x_pos = (width - barcode_w) / 2
        y_pos = 0.5 * inch  # ~0.5 inch from bottom
        c.drawImage(barcode_filename, x_pos, y_pos, width=barcode_w, height=barcode_h)
    else:
        c.setFont("Helvetica", 10)
        c.drawString(15, 0.5 * inch, "Barcode generation failed.")

    c.showPage()
    c.save()
    return label_filename

###############################################################################
# 4) Gradio function to process file uploads
###############################################################################
def process_file(file_obj):
    """
    Reads CSV/Excel, checks columns, 
    generates one label per row, zips them.
    """
    try:
        # Clean out old labels/barcodes
        for f in os.listdir(LABELS_DIR):
            os.remove(os.path.join(LABELS_DIR, f))
        for f in os.listdir(BARCODES_DIR):
            os.remove(os.path.join(BARCODES_DIR, f))

        # Read the uploaded file
        if file_obj.name.endswith(".csv"):
            df = pd.read_csv(file_obj)
        elif file_obj.name.endswith((".xls", ".xlsx")):
            df = pd.read_excel(file_obj)
        else:
            return "Invalid file format. Please upload a .csv, .xls, or .xlsx file.", None

        # Check required columns
        missing = [col for col in REQUIRED_COLUMNS if col not in df.columns]
        if missing:
            return f"Missing columns: {', '.join(missing)}", None

        # Generate labels
        for i, row in df.iterrows():
            create_usps_label(row.to_dict(), index=i+1)

        # Zip them up
        zip_filename = "usps_labels.zip"
        with zipfile.ZipFile(zip_filename, "w") as zf:
            for f in os.listdir(LABELS_DIR):
                if f.endswith(".pdf"):
                    zf.write(os.path.join(LABELS_DIR, f), f)

        return "Labels generated successfully.", zip_filename

    except Exception as e:
        return f"Error: {str(e)}", None

###############################################################################
# 5) Gradio Interface for Hugging Face
###############################################################################
iface = gr.Interface(
    fn=process_file,
    inputs=gr.File(type="filepath"),
    outputs=[gr.Text(label="Status"), gr.File(label="Download Zipped Labels")],
    title="USPS-Style Label Generator (4x6)",
    description=(
        "Upload a CSV/XLS/XLSX file with columns:\n"
        "Order ID, Order Date, Shipper Name, Shipper Address, Shipper Phone,\n"
        "Receiver Name, Receiver Address, Receiver Phone, Package Weight (kg),\n"
        "Shipping Method, Tracking Number, Estimated Delivery Date\n\n"
        "Generates a 4x6 USPS-style PDF label per row, including lines that match the sample."
    ),
)

if __name__ == "__main__":
    iface.launch()