#!/usr/bin/env python3
"""Extract DBNames records from exported 1C SQL Params files.

DBNames is the platform-maintained map between metadata GUIDs, storage roles
such as Reference/Fld/Document/InfoRg, and numeric SQL suffixes. This extractor
keeps those platform labels as-is and does not translate them to 1C metadata
object kinds.
"""

from __future__ import annotations

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

from inspect_1c_sql_files import Lexer, Parser, try_decode, try_decompress


def unwrap_bom_sequence(value: Any) -> Any:
    if (
        isinstance(value, dict)
        and value.get("type") == "sequence"
        and len(value.get("items") or []) == 2
        and isinstance(value["items"][0], dict)
        and value["items"][0].get("type") == "atom"
        and str(value["items"][0].get("value") or "").strip("\ufeff") == ""
    ):
        return value["items"][1]
    return value


def scalar(value: Any) -> str:
    if isinstance(value, dict) and value.get("type") in {"atom", "string"}:
        return str(value.get("value") or "")
    return ""


def parse_dbnames(path: Path) -> dict[str, Any]:
    payload, compression = try_decompress(path.read_bytes())
    text, encoding = try_decode(payload)
    if text is None:
        raise ValueError(f"{path.name}: cannot decode text")
    text = text.replace("\x00", "")
    first_brace = text.find("{")
    if first_brace > 0:
        text = text[first_brace:]
    else:
        text = text.lstrip("\ufeff")
    parsed = unwrap_bom_sequence(Parser(Lexer(text).tokens()).parse())
    if not (isinstance(parsed, dict) and parsed.get("type") == "list"):
        raise ValueError(f"{path.name}: expected root list")
    items = parsed.get("items") or []
    if len(items) != 2:
        raise ValueError(f"{path.name}: expected 2 root items, got {len(items)}")
    root_number = scalar(items[0])
    records_node = items[1]
    if not (isinstance(records_node, dict) and records_node.get("type") == "list"):
        raise ValueError(f"{path.name}: expected records list")
    record_items = records_node.get("items") or []
    declared_count = int(scalar(record_items[0]) or "0") if record_items else 0
    records = []
    for index, node in enumerate(record_items[1:], start=1):
        if not (isinstance(node, dict) and node.get("type") == "list"):
            continue
        fields = node.get("items") or []
        if len(fields) != 3:
            records.append({"index": index, "status": "unexpected_shape", "field_count": len(fields)})
            continue
        records.append(
            {
                "index": index,
                "guid": scalar(fields[0]).lower(),
                "storage_role": scalar(fields[1]),
                "sql_number": int(scalar(fields[2])),
                "status": "parsed",
            }
        )
    return {
        "file_name": path.name,
        "compression": compression,
        "encoding": encoding,
        "root_number": int(root_number),
        "declared_count": declared_count,
        "record_count": len(records),
        "records": records,
    }


def main() -> int:
    parser = argparse.ArgumentParser(description="Extract DBNames records from exported Params files.")
    parser.add_argument("params_dir", type=Path)
    parser.add_argument("--output", type=Path, required=True)
    args = parser.parse_args()

    files = sorted(path for path in args.params_dir.iterdir() if path.is_file() and path.name.startswith("DBNames") and not path.name.startswith("DBNamesVersion-"))
    result = {
        "schema": "onec_sql_dbnames.v1",
        "source": str(args.params_dir),
        "file_count": len(files),
        "dbnames": [parse_dbnames(path) for path in files],
    }
    summary: dict[str, int] = {}
    for dbnames in result["dbnames"]:
        for record in dbnames["records"]:
            role = record.get("storage_role") or "<unknown>"
            summary[role] = summary.get(role, 0) + 1
    result["storage_role_counts"] = dict(sorted(summary.items(), key=lambda item: (-item[1], item[0])))
    args.output.parent.mkdir(parents=True, exist_ok=True)
    args.output.write_text(json.dumps(result, ensure_ascii=False, indent=2) + "\n", encoding="utf-8")
    print(json.dumps({"output": str(args.output), "files": len(files), "roles": len(summary)}, ensure_ascii=False))
    return 0


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