from __future__ import annotations

import argparse
import hashlib
import json
from pathlib import Path

from common import read_json
from prepare_1c_rag_corpus import SUPPORTED_EXTENSIONS, classify_source, normalize_text, parse_front_matter


ROOT = Path(__file__).resolve().parents[1]
DEFAULT_SOURCE_DIR = ROOT / "plugins" / "1c" / "rag" / "sources"
DEFAULT_MANIFEST = ROOT / "plugins" / "1c" / "datasets" / "prepared" / "rag_manifest.json"


def iter_source_files(source_dir: Path) -> list[Path]:
    if not source_dir.exists():
        return []
    return sorted(
        path
        for path in source_dir.rglob("*")
        if path.is_file() and path.suffix.lower() in SUPPORTED_EXTENSIONS
    )


def source_state(source_dir: Path) -> dict[str, dict]:
    state = {}
    for path in iter_source_files(source_dir):
        relative_path = path.relative_to(source_dir).as_posix()
        text = normalize_text(path.read_text(encoding="utf-8"))
        front_matter, body = parse_front_matter(text)
        chunk_source_text = body or text
        state[relative_path] = {
            "source_path": relative_path,
            "source_type": classify_source(path, chunk_source_text, front_matter),
            "file_type": path.suffix.lower().lstrip("."),
            "content_hash": hashlib.sha256(text.encode("utf-8")).hexdigest(),
        }
    return state


def compare_manifest(source_dir: Path, manifest_path: Path) -> dict:
    current = source_state(source_dir)
    if not manifest_path.exists():
        return {
            "status": "stale" if current else "missing",
            "reason": "manifest is missing",
            "new": sorted(current),
            "changed": [],
            "deleted": [],
            "type_changed": [],
        }

    manifest = read_json(manifest_path)
    recorded = {
        str(source.get("source_path")): source
        for source in manifest.get("sources") or []
        if isinstance(source, dict) and source.get("source_path")
    }

    current_paths = set(current)
    recorded_paths = set(recorded)
    new = sorted(current_paths - recorded_paths)
    deleted = sorted(recorded_paths - current_paths)
    changed = []
    type_changed = []

    for source_path in sorted(current_paths & recorded_paths):
        current_source = current[source_path]
        recorded_source = recorded[source_path]
        if current_source["content_hash"] != recorded_source.get("content_hash"):
            changed.append(source_path)
        if current_source["source_type"] != recorded_source.get("source_type"):
            type_changed.append(
                {
                    "source_path": source_path,
                    "current": current_source["source_type"],
                    "manifest": recorded_source.get("source_type"),
                }
            )

    stale = bool(new or deleted or changed or type_changed)
    return {
        "status": "stale" if stale else "fresh",
        "source_dir": str(source_dir),
        "manifest": str(manifest_path),
        "source_count": len(current),
        "manifest_source_count": len(recorded),
        "new": new,
        "changed": changed,
        "deleted": deleted,
        "type_changed": type_changed,
    }


def main() -> int:
    parser = argparse.ArgumentParser(description="Check whether the 1C RAG manifest is fresh.")
    parser.add_argument("--source-dir", type=Path, default=DEFAULT_SOURCE_DIR)
    parser.add_argument("--manifest", type=Path, default=DEFAULT_MANIFEST)
    parser.add_argument("--print", action="store_true")
    args = parser.parse_args()

    report = compare_manifest(args.source_dir, args.manifest)
    if args.print:
        print(json.dumps(report, ensure_ascii=False, indent=2))
    else:
        print(f"1C RAG freshness: {report['status']}")
    return 0 if report["status"] in {"fresh", "missing"} else 1


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