#!/usr/bin/env python3
"""Build a GUID index for a 1C XML configuration dump.

The index is intentionally mechanical: it records GUID occurrences in XML
attributes and element text, plus the top metadata object declared by each
file. It does not infer SQL table names or storage roles.
"""

from __future__ import annotations

import argparse
import json
import os
import re
from pathlib import Path
from typing import Any


GUID_RE = re.compile(
    r"[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}"
)
TOP_OBJECT_RE = re.compile(
    r"<(?P<kind>[A-Za-z][A-Za-z0-9]*)\s+[^>]*uuid=\"(?P<guid>"
    + GUID_RE.pattern
    + r")\"",
    re.S,
)
NAME_RE = re.compile(r"<Name>(?P<name>.*?)</Name>", re.S)
SYNONYM_RE = re.compile(r"<(?:[A-Za-z0-9]+:)?content>(?P<content>.*?)</(?:[A-Za-z0-9]+:)?content>", re.S)


def clean_xml_text(value: str) -> str:
    return repair_mojibake(
        value.replace("&quot;", '"')
        .replace("&apos;", "'")
        .replace("&lt;", "<")
        .replace("&gt;", ">")
        .replace("&amp;", "&")
        .strip()
    )


def repair_mojibake(value: str) -> str:
    if not value:
        return value
    for source_encoding in ("gbk", "cp1255", "cp1252", "latin1"):
        try:
            candidate = value.encode(source_encoding).decode("cp1251")
        except UnicodeError:
            continue
        candidate_cyrillic = sum(1 for char in candidate if "А" <= char <= "я" or char == "ё" or char == "Ё")
        value_cyrillic = sum(1 for char in value if "А" <= char <= "я" or char == "ё" or char == "Ё")
        if candidate_cyrillic > value_cyrillic:
            return repair_mojibake(candidate)
    cjk_count = sum(1 for char in value if "\u4e00" <= char <= "\u9fff")
    if cjk_count:
        try:
            candidate = value.encode("gbk").decode("cp1251")
            return repair_mojibake(candidate)
        except UnicodeError:
            pass
    cyrillic_count = sum(1 for char in value if "А" <= char <= "я" or char == "ё" or char == "Ё")
    suspicious_count = sum(1 for char in value if char in "ÐÑÂÃÄÅÆÇÈÉÊËÌÍÎÏÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïòóôõö÷øùúûüýþÿ")
    if suspicious_count <= cyrillic_count:
        return value
    try:
        repaired = value.encode("latin1").decode("cp1251")
    except UnicodeError:
        return value
    repaired_cyrillic = sum(1 for char in repaired if "А" <= char <= "я" or char == "ё" or char == "Ё")
    return repaired if repaired_cyrillic > cyrillic_count else value


def inspect_xml_file(path: Path, root_dir: Path, *, max_occurrences_per_file: int) -> dict[str, Any]:
    item: dict[str, Any] = {
        "path": repair_mojibake(str(path)),
        "relative_path": repair_mojibake(str(path.relative_to(root_dir))),
        "status": "ok",
        "root_tag": "",
        "top_object": None,
        "occurrences": [],
    }
    try:
        text = path.read_text(encoding="utf-8", errors="replace")
    except OSError as exc:
        item["status"] = "read_error"
        item["error"] = str(exc)
        return item

    root_match = re.search(r"<(?P<tag>[A-Za-z][A-Za-z0-9]*)[\s>]", text)
    item["root_tag"] = root_match.group("tag") if root_match else ""

    object_match = TOP_OBJECT_RE.search(text)
    if object_match:
        object_start = object_match.start()
        object_end = TOP_OBJECT_RE.search(text, object_match.end())
        object_fragment = text[object_start : object_end.start() if object_end else min(len(text), object_start + 500_000)]
        name_match = NAME_RE.search(object_fragment)
        synonym_match = SYNONYM_RE.search(object_fragment)
        top_object = {
            "guid": object_match.group("guid").lower(),
            "xml_kind": object_match.group("kind"),
            "name": clean_xml_text(name_match.group("name")) if name_match else "",
            "synonym": clean_xml_text(synonym_match.group("content")) if synonym_match else "",
        }
    else:
        top_object = None
    item["top_object"] = top_object

    occurrences = []
    for match in GUID_RE.finditer(text):
        occurrences.append({"guid": match.group(0).lower(), "offset": match.start()})
        if len(occurrences) >= max_occurrences_per_file:
            item["occurrences"] = occurrences
            item["truncated"] = True
            return item
    item["occurrences"] = occurrences
    item["truncated"] = False
    return item


def build_guid_map(files: list[dict[str, Any]], *, max_occurrences_per_guid: int) -> dict[str, Any]:
    guid_map: dict[str, Any] = {}
    for file_item in files:
        if file_item.get("status") != "ok":
            continue
        top_object = file_item.get("top_object")
        if top_object:
            guid = top_object["guid"]
            entry = guid_map.setdefault(guid, {"total_occurrences": 0, "top_objects": [], "occurrences": []})
            entry["top_objects"].append(
                {
                    "path": file_item["path"],
                    "relative_path": file_item["relative_path"],
                    "xml_kind": top_object["xml_kind"],
                    "name": top_object["name"],
                    "synonym": top_object["synonym"],
                }
            )
        for occurrence in file_item.get("occurrences") or []:
            guid = occurrence["guid"]
            entry = guid_map.setdefault(guid, {"total_occurrences": 0, "top_objects": [], "occurrences": []})
            entry["total_occurrences"] += 1
            if len(entry["occurrences"]) < max_occurrences_per_guid:
                entry["occurrences"].append(
                    {
                        "path": file_item["path"],
                        "relative_path": file_item["relative_path"],
                        "offset": occurrence["offset"],
                    }
                )
    return dict(sorted(guid_map.items()))


def list_xml_paths(root: Path, max_relative_depth: int) -> list[Path]:
    if max_relative_depth <= 0:
        return sorted(root.rglob("*.xml"))
    result: list[Path] = []
    root_parts = len(root.parts)
    for current, dirs, files in os.walk(root):
        current_path = Path(current)
        relative_depth = len(current_path.parts) - root_parts
        if relative_depth >= max_relative_depth - 1:
            dirs[:] = []
        for file_name in files:
            if file_name.lower().endswith(".xml"):
                path = current_path / file_name
                if len(path.relative_to(root).parts) <= max_relative_depth:
                    result.append(path)
    return sorted(result)


def main() -> int:
    parser = argparse.ArgumentParser(description="Build a GUID index for a 1C XML dump.")
    parser.add_argument("xml_root", type=Path)
    parser.add_argument("--output", type=Path, required=True)
    parser.add_argument("--max-occurrences-per-file", type=int, default=5000)
    parser.add_argument("--max-occurrences-per-guid", type=int, default=20)
    parser.add_argument(
        "--max-relative-depth",
        type=int,
        default=0,
        help="Only scan XML files whose relative path has at most this many parts; 0 scans all files.",
    )
    args = parser.parse_args()

    xml_root = args.xml_root.resolve()
    paths = list_xml_paths(xml_root, args.max_relative_depth)
    files = [
        inspect_xml_file(path, xml_root, max_occurrences_per_file=args.max_occurrences_per_file)
        for path in paths
    ]
    guid_map = build_guid_map(files, max_occurrences_per_guid=args.max_occurrences_per_guid)
    top_object_count = sum(1 for item in files if item.get("top_object"))
    parse_errors = sum(1 for item in files if item.get("status") != "ok")
    report = {
        "schema": "onec_xml_guid_index.v1",
        "xml_root": repair_mojibake(str(xml_root)),
        "file_count": len(files),
        "top_object_count": top_object_count,
        "parse_error_count": parse_errors,
        "guid_count": len(guid_map),
        "files": files,
        "guid_map": guid_map,
    }
    args.output.parent.mkdir(parents=True, exist_ok=True)
    args.output.write_text(json.dumps(report, ensure_ascii=False, indent=2) + "\n", encoding="utf-8")
    print(
        json.dumps(
            {
                "output": str(args.output),
                "files": len(files),
                "top_objects": top_object_count,
                "guids": len(guid_map),
                "parse_errors": parse_errors,
            },
            ensure_ascii=False,
        )
    )
    return 0


if __name__ == "__main__":
    raise SystemExit(main())