import sys
import struct
import os

# Opcode constants
TYPE1_NOP = 0xC00000 
TYPE6_AX0 = 0x400000 
TYPE10_JUMP_ALWAYS = 0x18000F 
TYPE30_NOP = 0x000000 

def create_rom(filename, format=3):
    """
    Creates a synthetic ADSP-219x ROM with known instruction patterns.
    """
    os.makedirs(os.path.dirname(filename), exist_ok=True)
    instructions = [
        0x000000,                  # 0x0000: NOP
        0x401230 | 0x0,            # 0x0001: AX0 = 0x1234 (Type 6, simplified field)
        0x502000 | 0x0,            # 0x0002: I0 = 0x2000 (Type 7)
        0x500010 | 0x4,            # 0x0003: M0 = 1 (Type 7)
        0xC00000 | (0x13<<13) | (0x0<<11) | (0x0<<8) | (0x0<<2) | (0x0), 
                                   # 0x0004: X+Y, AX0=DM(I0+=M0), AY0=PM(I4+=M4)
        0x18010F,                  # 0x0005: JUMP 0x0100
    ]
    
    with open(filename, "wb") as f:
        for ins in instructions:
            if format == 3:
                # Big-endian 3-byte pack
                f.write(struct.pack(">I", ins)[1:])
            else:
                # Big-endian 4-byte pad
                f.write(struct.pack(">I", ins))

if __name__ == "__main__":
    # Ensure full path to base_test.bin
    base_dir = os.path.dirname(os.path.abspath(__file__))
    create_rom(os.path.join(base_dir, "test_roms/base_test.bin"), 3)
    create_rom(os.path.join(base_dir, "test_roms/padded_test.bin"), 4)
    print("Test ROMs generated in test_roms/")