/*
* memory_open
*
* Begin output redirection to the memory of the Z-machine.
*
*/
internal static void MemoryOpen(zword table, zword xsize, bool buffering)
{
if (++depth < MAX_NESTING)
{
if (!buffering)
{
xsize = 0xffff;
}
if (buffering && (short)xsize <= 0)
{
xsize = Screen.GetMaxWidth((zword)(-(short)xsize));
}
FastMem.StoreW(table, 0);
redirect[depth].Table = table;
redirect[depth].Width = 0;
redirect[depth].Total = 0;
redirect[depth].XSize = xsize;
Main.ostream_memory = true;
}
else
{
Err.RuntimeError(ErrorCodes.ERR_STR3_NESTING);
}
}/* memory_open */
}/* z_check_unicode */
/*
* z_encode_text, encode a ZSCII string for use in a dictionary.
*
* zargs[0] = address of text buffer
* zargs[1] = length of ASCII string
* zargs[2] = offset of ASCII string within the text buffer
* zargs[3] = address to store encoded text in
*
* This is a V5+ opcode and therefore the dictionary resolution must be
* three 16bit words.
*
*/
internal static void ZEncodeText()
{
LoadString((zword)(Process.zargs[0] + Process.zargs[2]), Process.zargs[1]);
EncodeText(0x05);
if (Encoded is null)
{
ThrowHelper.ThrowInvalidOperationException("Encoding not initialized.");
}
for (int i = 0; i < Resolution; i++)
{
FastMem.StoreW((zword)(Process.zargs[3] + 2 * i), Encoded[i]);
}
}/* z_encode_text */
}/* z_push */
/*
* z_push_stack, push a value onto a user stack then branch if successful.
*
* zargs[0] = value to push onto the stack
* zargs[1] = address of user stack
*
*/
internal static void ZPushStack()
{
zword addr = Process.zargs[1];
FastMem.LowWord(addr, out ushort size);
if (size != 0)
{
FastMem.StoreW((zword)(addr + 2 * size), Process.zargs[0]);
size--;
FastMem.StoreW(addr, size);
}
Process.Branch(size > 0); // TODO I think that's what's expected here
}/* z_push_stack */
internal static void ZPop() => Main.sp++; /* z_pop */
/*
* z_pop_stack, pop n values off the game or user stack and discard them.
*
* zargs[0] = number of values to discard
* zargs[1] = address of user stack (optional)
*
*/
internal static void ZPopStack()
{
if (Process.zargc == 2)
{ /* it's a user stack */
zword addr = Process.zargs[1];
FastMem.LowWord(addr, out ushort size);
size += Process.zargs[0];
FastMem.StoreW(addr, size);
}
else
{
Main.sp += Process.zargs[0]; /* it's the game stack */
}
}/* z_pop_stack */
}/* z_pop_stack */
/*
* z_pull, pop a value off...
*
* a) ...the game or a user stack and store it (V6)
*
* zargs[0] = address of user stack (optional)
*
* b) ...the game stack and write it to a variable (other than V6)
*
* zargs[0] = variable to write value to
*
*/
internal static void ZPull()
{
zword value;
if (Main.h_version != ZMachine.V6)
{ /* not a V6 game, pop stack and write */
value = Main.Stack[Main.sp++];
if (Process.zargs[0] == 0)
{
Main.Stack[Main.sp] = value;
}
else if (Process.zargs[0] < 16)
{
// *(fp - Process.zargs[0]) = value;
Main.Stack[Main.fp - Process.zargs[0]] = value;
}
else
{
zword addr = (zword)(Main.h_globals + 2 * (Process.zargs[0] - 16));
FastMem.SetWord(addr, value);
}
}
else
{ /* it's V6, but is there a user stack? */
if (Process.zargc == 1)
{ /* it's a user stack */
zword addr = Process.zargs[0];
FastMem.LowWord(addr, out ushort size);
size++;
FastMem.StoreW(addr, size);
addr += (zword)(2 * size);
FastMem.LowWord(addr, out value);
}
else
{
value = Main.Stack[Main.sp++];// value = *sp++; /* it's the game stack */
}
Process.Store(value);
}
}/* z_pull */
}/* memory_new_line */
/*
* memory_word
*
* Redirect a string of characters to the memory of the Z-machine.
*
*/
internal static void MemoryWord(ReadOnlySpan <zword> s)
{
zword addr;
zword c;
int pos = 0;
if (Main.h_version == ZMachine.V6)
{
int width = OS.StringWidth(s);
if (redirect[depth].XSize != 0xffff)
{
if (redirect[depth].Width + width > redirect[depth].XSize)
{
if (s[pos] is ' ' or CharCodes.ZC_INDENT or CharCodes.ZC_GAP)
{
width = OS.StringWidth(s.Slice(++pos));
}
MemoryNewline();
}
}
redirect[depth].Width += (zword)width;
}
addr = redirect[depth].Table;
FastMem.LowWord(addr, out zword size);
addr += 2;
while ((c = s[pos++]) != 0)
{
FastMem.StoreB((zword)(addr + (size++)), Text.TranslateToZscii(c));
}
FastMem.StoreW(redirect[depth].Table, size);
}/* memory_word */
}/* memory_open */
/*
* memory_new_line
*
* Redirect a newline to the memory of the Z-machine.
*
*/
internal static void MemoryNewline()
{
zword addr;
redirect[depth].Total += redirect[depth].Width;
redirect[depth].Width = 0;
addr = redirect[depth].Table;
FastMem.LowWord(addr, out zword size);
addr += 2;
if (redirect[depth].XSize != 0xffff)
{
redirect[depth].Table = (zword)(addr + size);
size = 0;
}
else
{
FastMem.StoreB((zword)(addr + (size++)), 13);
}
FastMem.StoreW(redirect[depth].Table, size);
}/* memory_new_line */
} /* z_storeb */
/*
* z_storew, write a word into a table of words.
*
* zargs[0] = address of table
* zargs[1] = index of table entry
* zargs[2] = value to be written
*
*/
internal static void ZStoreW()
{
FastMem.StoreW((zword)(Process.zargs[0] + 2 * Process.zargs[1]), Process.zargs[2]);
} /* z_storew */
