"""
Lamp ID labels on the Brother QL-820NWB (DK-11221, 23x23 mm die-cut).

Each label carries the lamp ID as a QR code and as text. These are internal
inventory labels: scanning one with the station's barcode scanner types the
ID, which drops straight into the re-measure flow. The station prints two
per lamp: one for the box, one for the lamp itself.

Printer address comes from --printer or the HPCS_LABEL_PRINTER environment
variable, e.g. tcp://192.168.1.50 (the QL-820NWB listens on port 9100).

Usage:
    uv run label_printer.py L0006                     # print 2 labels
    uv run label_printer.py L0006 --copies 1
    uv run label_printer.py L0006 --preview out.png   # render only, no printer
"""

import argparse
import os
import sys

import qrcode
from PIL import Image, ImageDraw, ImageFont

LABEL_ID = "23x23"  # DK-11221
DOTS = (202, 202)  # printable area of the 23x23 label
MODEL = "QL-820NWB"
TEXT_HEIGHT = 52  # bottom strip for the ID text


def _font(size):
    for name in ("arialbd.ttf", "arial.ttf", "DejaVuSans-Bold.ttf"):
        try:
            return ImageFont.truetype(name, size)
        except OSError:
            continue
    return ImageFont.load_default(size)


def render_label(lamp_id: str) -> Image.Image:
    """202x202 1-bit label: the bare lamp ID as QR on top, as text below."""
    image = Image.new("1", DOTS, 1)

    # Just the ID (internal use): a 5-character QR stays at version 1, so the
    # modules print large and scan reliably at 23 mm. Scanning it at the
    # station types the ID and lands in the re-measure flow.
    qr = qrcode.QRCode(
        error_correction=qrcode.constants.ERROR_CORRECT_M,
        box_size=1,
        border=2,  # quiet zone; tight but fine for close-range scanning
    )
    qr.add_data(lamp_id.upper())
    qr.make(fit=True)
    modules = len(qr.get_matrix())
    qr_size = DOTS[1] - TEXT_HEIGHT
    qr.box_size = max(1, qr_size // modules)
    qr_img = qr.make_image().get_image().convert("1")
    image.paste(qr_img, ((DOTS[0] - qr_img.width) // 2, (qr_size - qr_img.height) // 2))

    draw = ImageDraw.Draw(image)
    size = 44
    while size > 10:
        font = _font(size)
        box = draw.textbbox((0, 0), lamp_id, font=font)
        if box[2] - box[0] <= DOTS[0] - 8:
            break
        size -= 2
    draw.text(
        ((DOTS[0] - (box[2] - box[0])) // 2 - box[0], DOTS[1] - TEXT_HEIGHT + (TEXT_HEIGHT - (box[3] - box[1])) // 2 - box[1]),
        lamp_id,
        font=font,
        fill=0,
    )
    return image


def print_labels(lamp_id: str, printer: str, copies: int = 2) -> None:
    """Render and send `copies` labels to the QL-820NWB."""
    from brother_ql.backends.helpers import send
    from brother_ql.conversion import convert
    from brother_ql.raster import BrotherQLRaster

    image = render_label(lamp_id)
    raster = BrotherQLRaster(MODEL)
    instructions = convert(qlr=raster, images=[image] * copies, label=LABEL_ID, cut=True)
    send(instructions=instructions, printer_identifier=printer, backend_identifier="network", blocking=True)


def main():
    parser = argparse.ArgumentParser(description="Print lamp ID labels (QR + ID)")
    parser.add_argument("lamp_id", help="e.g. L0006")
    parser.add_argument("--printer", default=os.environ.get("HPCS_LABEL_PRINTER", ""),
                        help="tcp://<ip> of the QL-820NWB (default: HPCS_LABEL_PRINTER env)")
    parser.add_argument("--copies", type=int, default=2)
    parser.add_argument("--preview", metavar="PNG",
                        help="Write the rendered label to a PNG instead of printing")
    args = parser.parse_args()

    lamp_id = args.lamp_id.upper()
    if args.preview:
        render_label(lamp_id).save(args.preview)
        print(f"Wrote {args.preview}")
        return
    if not args.printer:
        print("ERROR: no printer configured. Pass --printer tcp://<ip> or set HPCS_LABEL_PRINTER.")
        sys.exit(1)
    print_labels(lamp_id, args.printer, args.copies)
    print(f"Printed {args.copies} label(s) for {lamp_id} on {args.printer}")


if __name__ == "__main__":
    main()