#!/usr/bin/env python3
"""Build a Chinese translate.lua for the 40250 quest system.

The 40250 quests say `gameforge.<quest>.<key>`; game loads these strings from
share/locale/<locale>/translate.lua when it starts (questlua.cpp), so a new
translate.lua only needs a restart, not a quest recompile.

data/zh_40250/quest_translate_zh.tsv holds the reviewed translations, one
`<quest>.<key>\\t<text>` row per string, UTF-8. `[ENTER]` in a translation is a
deliberate line break; each line is re-wrapped to the quest window width
(CJK characters count double). A key without a row keeps its English text, and a
row fills every key whose English text equals the translated key's.

  build_zh_translate_lua.py build <out translate.lua>   GBK, for the server
  build_zh_translate_lua.py todo <dir> [--quests a,b] [--chunk N]
                                                        untranslated unique strings
"""

import argparse
import re
import unicodedata
from pathlib import Path


REPO = Path(__file__).resolve().parents[1]
DEFAULT_EN = REPO.parent / "40250/Server Client TMP4/Server/metin2/server/share/locale/english/translate.lua"
DEFAULT_TABLE = REPO / "data/zh_40250/quest_translate_zh.tsv"
ROW = re.compile(r'^gameforge\.(\S+)\s*=\s*"(.*)"\s*$')
WIDTH = 50  # columns; the English lines are wrapped at about 50 characters


def english_rows(path: Path):
    """[(key, text)] in file order; the file is cp1252."""
    rows = []
    for line in path.read_bytes().decode("cp1252").splitlines():
        match = ROW.match(line)
        if match:
            rows.append((match.group(1), match.group(2)))
    return rows


def table_rows(path: Path):
    rows = {}
    if path.is_file():
        for number, line in enumerate(path.read_text(encoding="utf-8").splitlines(), 1):
            if not line or line.startswith("#"):
                continue
            key, sep, text = line.partition("\t")
            if not sep:
                raise ValueError(f"{path}:{number}: no tab")
            rows[key] = text
    return rows


def columns(char: str) -> int:
    return 2 if unicodedata.east_asian_width(char) in "WF" else 1


def wrap(line: str, width: int = WIDTH):
    """Break a line at the width; CJK text breaks anywhere, ASCII words, %s and [TAG ...] stay whole."""
    tokens = re.findall(r"\[/?[A-Z]+[^\]\[]*\]|%[-+ #0-9.]*[a-zA-Z]|[A-Za-z0-9_'.,!?:;()/-]+|\s+|.", line)
    lines, current, used = [], "", 0
    for token in tokens:
        # A tag such as [COLOR r;1|g;0|b;0] or [DELAY value;150] takes no room on screen.
        size = 0 if re.fullmatch(r"\[/?[A-Z]+[^\]\[]*\]", token) else sum(columns(c) for c in token)
        if used + size > width and current.strip():
            lines.append(current.rstrip())
            current, used = "", 0
            if token.isspace():
                continue
        current += token
        used += size
    lines.append(current)
    return lines


def layout(text: str) -> str:
    return "[ENTER]".join(part for line in text.split("[ENTER]") for part in wrap(line))


# English text left untranslated, in characters GBK has no code for.
ASCII = str.maketrans({"\u2018": "'", "\u2019": "'", "\u00b4": "'", "\u201c": "'", "\u201d": "'",
                       "\u2013": "-", "\u2014": "-", "\u2026": "...", "\u00a0": " "})


def english_text(text: str) -> str:
    text = text.translate(ASCII)
    return "".join(c if c.isascii() else "?" for c in text)


def translations(english, table):
    """key -> Chinese text for every key, by key or by an equal English text."""
    by_text = {}
    for key, text in english:
        if key in table:
            by_text.setdefault(text, table[key])
    return {key: table.get(key, by_text.get(text)) for key, text in english}


def build(en: Path, table_path: Path, output: Path):
    english = english_rows(en)
    table = table_rows(table_path)
    unknown = sorted(set(table) - {key for key, _ in english})
    if unknown:
        raise ValueError(f"keys not in translate.lua: {unknown[:10]}")
    chinese = translations(english, table)
    lines = []
    done = 0
    # The English file line by line (it also creates the nested tables), with the values replaced.
    for line in en.read_bytes().decode("cp1252").splitlines():
        match = ROW.match(line)
        if line.startswith("exportTestForCharset"):
            lines.append('exportTestForCharset = "\u4e2d\u6587 "'.encode("gbk"))
            continue
        if not match:
            lines.append(english_text(line).encode("ascii"))
            continue
        key, text = match.groups()
        if chinese[key] is not None:
            # Keep the English leading/trailing spaces: quests join some strings with names.
            lead = text[: len(text) - len(text.lstrip(" "))]
            trail = text[len(text.rstrip(" ")):]
            body = layout(chinese[key].strip(" "))
            if '"' in body or "\\" in body:
                raise ValueError(f"{key}: no quotes or backslashes in a translation")
            # A GBK trail byte can be 0x5C, which Lua reads as an escape; doubled it stays one byte.
            value = lead.encode() + body.encode("gbk").replace(b"\\", b"\\\\") + trail.encode()
            done += 1
        else:
            value = english_text(text).encode("ascii")  # Lua source as in the English file
        lines.append(f"gameforge.{key} = \"".encode("ascii") + value + b'"')
    output.write_bytes(b"\n".join(lines) + b"\n")
    return done, len(english)


def todo(en: Path, table_path: Path, out_dir: Path, quests=None, chunk=120):
    english = english_rows(en)
    chinese = translations(english, table_rows(table_path))
    seen, pending = set(), []
    for key, text in english:
        if chinese[key] is None and text not in seen and (not quests or key.split(".")[0] in quests):
            seen.add(text)
            pending.append((key, text))
    out_dir.mkdir(parents=True, exist_ok=True)
    for old in out_dir.glob("todo_*.tsv"):
        old.unlink()
    for index in range(0, len(pending), chunk):
        part = pending[index:index + chunk]
        (out_dir / f"todo_{index // chunk:03d}.tsv").write_text(
            "".join(f"{key}\t{text}\n" for key, text in part), encoding="utf-8")
    return len(pending)


def main():
    parser = argparse.ArgumentParser(description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter)
    parser.add_argument("--english", type=Path, default=DEFAULT_EN)
    parser.add_argument("--table", type=Path, default=DEFAULT_TABLE)
    sub = parser.add_subparsers(dest="command", required=True)
    build_parser = sub.add_parser("build")
    build_parser.add_argument("output", type=Path)
    todo_parser = sub.add_parser("todo")
    todo_parser.add_argument("out_dir", type=Path)
    todo_parser.add_argument("--quests")
    todo_parser.add_argument("--chunk", type=int, default=120)
    args = parser.parse_args()
    if args.command == "build":
        done, total = build(args.english, args.table, args.output)
        print(f"{args.output}: {done} of {total} strings in Chinese")
    else:
        quests = set(args.quests.split(",")) if args.quests else None
        print(f"{todo(args.english, args.table, args.out_dir, quests, args.chunk)} strings to translate")


if __name__ == "__main__":
    main()