#!/usr/bin/env python3
"""Map ROM string refs to enclosing functions in the unidasm output."""
import bisect
import re
import struct

ASM = "/tmp/opencode/v22.asm"
ROM = "vt1200_v22.bin"
ROM_BASE = 0x07E40000

lines = []
with open(ASM) as f:
    for line in f:
        head = line.split(":", 1)[0].strip()
        try:
            a = int(head, 16)
        except ValueError:
            continue
        lines.append((a, line.rstrip("\n")))
addrs = [a for a, _ in lines]

# function prologues: MMTM SP, ... ; MOVE A14,A13
entries = []
for i, (a, t) in enumerate(lines):
    if "MMTM   SP," in t:
        # look ahead a few instructions for MOVE A14,A13
        for j in range(i + 1, min(i + 4, len(lines))):
            if "MOVE   A14,A13" in lines[j][1]:
                entries.append(a)
                break

print(f"{len(entries)} function entries (MMTM prologue)")


def enclosing(bitaddr):
    i = bisect.bisect_right(entries, bitaddr) - 1
    return entries[i] if i >= 0 else None


def main():
    image = open(ROM, "rb").read()
    pat = re.compile(r"DMUL|DMUX|demultiplex|Illegal slot|service class|"
                     r"STOP_SLOT|ATTN|DATA_B|Data_A|host_credits|Multiplex|"
                     r"insert_latjob|LAT_CREATE|LAT_CLOSE|LAT_SEND|lat session|"
                     r"slot|extinct|circuit|Circuit|Calloc")
    for m in re.finditer(rb"[\x20-\x7e]{4,}", image):
        s = m.group().decode("latin1")
        if not pat.search(s):
            continue
        off = m.start()
        val = (ROM_BASE + off) << 3
        p = struct.pack("<I", val)
        start = 0
        refs = []
        while True:
            i = image.find(p, start)
            if i < 0:
                break
            refs.append(i * 8)
            start = i + 1
        if not refs:
            continue
        for r in refs:
            e = enclosing(r)
            print(f"func 0x{(e or 0)//8:06X}  ref 0x{r//8:06X}  str 0x{off:06X}  {s!r}")


if __name__ == "__main__":
    main()