package de.platon42.mc68kemu


@OptIn(ExperimentalUnsignedTypes::class)
class Rom(start: Int, val rom: UByteArray) : MemoryRegion(start, rom.size) {
    override fun readByte(address: Int): Int {
        return rom[address - start].toInt()
    }

    override fun readWord(address: Int): Int {
        val i = address - start
        return (rom[i].toInt() shl 8) or rom[i + 1].toInt()
    }

    override fun readLong(address: Int): Int {
        val i = address - start
        return (rom[i].toInt() shl 24) or
                (rom[i + 1].toInt() shl 16) or
                (rom[i + 2].toInt() shl 8) or
                rom[i + 3].toInt()
    }

    override fun writeByte(address: Int, value: Int) = throw UnsupportedOperationException("Attempt to write to rom ${address.toHex(8)}")

    override fun writeWord(address: Int, value: Int) = throw UnsupportedOperationException("Attempt to write to rom ${address.toHex(8)}")

    override fun writeLong(address: Int, value: Int) = throw UnsupportedOperationException("Attempt to write to rom ${address.toHex(8)}")
}