# build-ml.ps1 - assemble vrow.s with cc65 and turn the result into vml.c, the
# Power C unit that holds the machine code as a byte array and calls it.
#
#   powershell -NoProfile -File build-ml.ps1
#
# Run it whenever vrow.s changes, then build.ps1 as usual. vml.c is generated:
# edit vrow.s, not vml.c.

$ErrorActionPreference = "Stop"
$here = $PSScriptRoot
$bin  = "D:\Development\Commodore\cc65-snapshot-win32\bin"
$ca65 = Join-Path $bin "ca65.exe"
$ld65 = Join-Path $bin "ld65.exe"
$addr = 0xC020          # where the routine lives; the parameter block is at $C000

$cfg = Join-Path $env:TEMP "vrow.cfg"
@"
MEMORY { M: start = `$C020, size = `$0100, file = "%O"; }
SEGMENTS { CODE: load = M, type = ro; }
"@ | Set-Content $cfg -Encoding ascii

$obj = Join-Path $env:TEMP "vrow.o"
$out = Join-Path $here "vrow.bin"
& $ca65 (Join-Path $here "vrow.s") -o $obj
if ($LASTEXITCODE) { throw "ca65 failed" }
& $ld65 -C $cfg -o $out $obj
if ($LASTEXITCODE) { throw "ld65 failed" }

$b = [IO.File]::ReadAllBytes($out)
$rows = @()
for ($i = 0; $i -lt $b.Length; $i += 12) {
    $n = [Math]::Min(12, $b.Length - $i)
    $rows += "    " + (($b[$i..($i + $n - 1)] | ForEach-Object { "$_" }) -join ", ")
}
$arr = $rows -join ",`n"

@"
/* vml.c - GENERATED by build-ml.ps1 from vrow.s. Do not edit by hand.
 *
 * The machine code row painter, kept as a byte array and called in place
 * through sys(). It is position independent; its parameters go through zero
 * page scratch `$22-`$28, which Power C leaves to ML routines.
 */

char mlcode[$($b.Length)] = {
$arr
};

/* nothing to install: the code runs where the array sits */
mlinit()
{
    return 0;
}

/* paint the screen row at address dst: len bytes from src, cursor at column cur
   (255 = none), rev = 128 for an all reverse row */
mlrow(src, len, dst, cur, rev)
unsigned src, dst;
int len, cur, rev;
{
    char *p;
    char a, x, y;

    p = (char *) 0x22;
    p[0] = src & 255;
    p[1] = src >> 8;
    p[2] = len;
    p[3] = dst & 255;
    p[4] = dst >> 8;
    p[5] = cur;
    p[6] = rev;
    a = 0;
    x = 0;
    y = 0;
    sys((unsigned) mlcode, &a, &x, &y);   /* c64 form: no bank argument */
    return 0;
}
"@ | Set-Content (Join-Path $here "vml.c") -Encoding utf8

Write-Host ("vrow.bin {0} bytes -> vml.c" -f $b.Length)