#!/usr/bin/env python3
"""Convert NUFLI .nuf binary to oscar64-compatible assembly/include files.

Usage:
    python3 nuf_to_asm.py input.nuf output_base

Output files:
    output_base.asm  - Assembly data file
    output_base.h    - C header with extern declarations
"""

import argparse
import sys
from pathlib import Path


def nuf_to_asm(nuf_data, output_base):
    """Convert NUFLI binary to assembly data."""
    out_path = Path(output_base)

    # Skip 2-byte load address header
    data = nuf_data[2:]

    # Assembly data file
    with open(out_path.with_suffix('.asm'), 'w') as f:
        f.write("; NUFLI image data - generated by nuf_to_asm.py\n")
        f.write("; Load at $2000, display with SYS 12288 ($3000)\n")
        f.write(f"; Total size: {len(data)} bytes\n\n")
        f.write(".segment \"NUFLI_DATA\"\n\n")

        # Export the data
        f.write(".export _nufli_data\n")
        f.write(".export _nufli_size\n\n")

        f.write("_nufli_data:\n")

        # Write data in rows of 16 bytes
        for i in range(0, len(data), 16):
            chunk = data[i:i+16]
            hex_bytes = ', '.join(f'${b:02x}' for b in chunk)
            f.write(f"    .byte {hex_bytes}\n")

        f.write(f"\n_nufli_size = {len(data)}\n")

    # C header file
    with open(out_path.with_suffix('.h'), 'w') as f:
        f.write("/* NUFLI image data - generated by nuf_to_asm.py */\n")
        f.write(f"#ifndef {out_path.name.upper().replace('.', '_')}_H\n")
        f.write(f"#define {out_path.name.upper().replace('.', '_')}_H\n\n")
        f.write(f"/* NUFLI data size: {len(data)} bytes */\n")
        f.write(f"extern const unsigned char nufli_data[{len(data)}];\n")
        f.write(f"extern const unsigned int nufli_size;\n\n")
        f.write("/* Display NUFLI image */\n")
        f.write("void nufli_display(void);\n\n")
        f.write("#endif\n")

    print(f"Wrote {out_path.with_suffix('.asm')} ({len(data)} bytes)")
    print(f"Wrote {out_path.with_suffix('.h')}")


def main(argv=None):
    ap = argparse.ArgumentParser(
        description="Convert NUFLI .nuf binary to oscar64 assembly"
    )
    ap.add_argument("input", help="Input .nuf file")
    ap.add_argument("output_base", help="Output base path (no extension)")
    args = ap.parse_args(argv)

    in_path = Path(args.input)
    if not in_path.exists():
        print(f"Error: {in_path} not found", file=sys.stderr)
        sys.exit(1)

    data = in_path.read_bytes()
    nuf_to_asm(data, args.output_base)


if __name__ == "__main__":
    main()