#!/usr/bin/env python3
"""Generate mpu-ctype-data.c from official Unicode 18.0.0 UCD files.

This script is a maintainer tool.  It is never run by Makefile/configure.
Place these already-downloaded files beside the script or pass their paths:
  DerivedCoreProperties.txt
  DerivedGeneralCategory.txt
"""
import argparse
import re
from pathlib import Path

BITS = {
    "Alphabetic": 0x01,
    "Uppercase": 0x02,
    "Lowercase": 0x04,
    "XID_Start": 0x10,
    "XID_Continue": 0x20,
}
DIGIT = 0x08

def parse_range(s):
    if ".." in s:
        a,b=s.split("..",1); return int(a,16),int(b,16)
    n=int(s,16); return n,n

def apply(path, flags, wanted, general=False):
    version_ok=False
    with path.open(encoding="utf-8") as f:
        for raw in f:
            if "18.0.0" in raw[:80]: version_ok=True
            line=raw.split("#",1)[0].strip()
            if not line or ";" not in line: continue
            field, prop=(x.strip() for x in line.split(";",1))
            bit = DIGIT if general and prop == "Nd" else wanted.get(prop)
            if bit is None: continue
            a,b=parse_range(field)
            if a > 0xffff: continue
            b=min(b,0xffff)
            for cp in range(a,b+1): flags[cp] |= bit
    if not version_ok:
        raise SystemExit(f"{path}: expected Unicode 18.0.0 data")

def main():
    ap=argparse.ArgumentParser()
    ap.add_argument("--core",default="DerivedCoreProperties.txt")
    ap.add_argument("--category",default="DerivedGeneralCategory.txt")
    ap.add_argument("--output",default="mpu-ctype-data.c")
    ns=ap.parse_args()
    flags=[0]*0x10000
    apply(Path(ns.core),flags,BITS)
    apply(Path(ns.category),flags,{},general=True)
    for cp in range(0xd800,0xe000): flags[cp]=0
    out=Path(ns.output)
    with out.open("w",encoding="utf-8") as f:
        f.write("/***************************************************************\n")
        f.write("  MPU-CTYPE-DATA.C\n\n")
        f.write("       Generated strict UCS-2 classification table.\n")
        f.write("       Unicode Character Database version: 18.0.0.\n")
        f.write(" ***************************************************************/\n\n")
        f.write("#include <libmpuio.h>\n#include <mpu-symbols.h>\n#include <mpu-ctype.h>\n\n")
        f.write("__mpu_hidden_decl( __mpu_ucs2_ctype );\n\n")
        f.write("const unsigned char __mpu_ucs2_ctype[65536] =\n{\n")
        for base in range(0,0x10000,16):
            vals=", ".join("0x%02x"%flags[base+i] for i in range(16))
            f.write("  %s, /* U+%04X..U+%04X */\n"%(vals,base,base+15))
        f.write("};\n")

if __name__ == "__main__": main()