#!/usr/bin/env python3
"""Sincronizeaza depozitul de documente cu un remote rclone (Google Drive) si
reconstruieste indexul RAG DOAR daca s-a schimbat efectiv ceva pe disc.

De ce prin rclone si nu direct cu Google Drive API: containerul e headless
(fara browser pentru OAuth interactiv) — rclone se configureaza o data cu un
cont de serviciu (`rclone config`, tip `drive`, `service_account_file=...`),
vezi README.md, sectiunea "Sincronizare cu Google Drive".

Config (`~/.maria-bridge/env`, vezi ops/env.example):
  DRIVE_REMOTE - tinta rclone, ex: gdrive:romfast/document_store
                 (gol = sincronizare dezactivata, doar upload manual din dashboard)
"""

from __future__ import annotations

import hashlib
import json
import subprocess
import sys
import time

import config
import indexer
import store

STATE_FILE_NAME = ".sync_state.json"


def _fingerprint() -> str:
    """Amprenta continutului depozitului (nume+mtime+marime), ca sa reindexam
    doar cand s-a schimbat efectiv ceva, nu la fiecare tur de sincronizare."""
    config.DOCS_DIR.mkdir(parents=True, exist_ok=True)
    h = hashlib.sha256()
    for f in sorted(config.DOCS_DIR.glob("*")):
        if f.is_file() and f.suffix in store.DOC_EXTENSIONS:
            st = f.stat()
            h.update(f"{f.name}:{st.st_mtime_ns}:{st.st_size}\n".encode())
    return h.hexdigest()


def _sync_state_path():
    return config.STATE_DIR / STATE_FILE_NAME


def read_sync_state() -> dict:
    try:
        return json.loads(_sync_state_path().read_text(encoding="utf-8"))
    except (OSError, ValueError):
        return {}


def _write_state(fingerprint: str, extra: dict | None = None) -> None:
    data = {"fingerprint": fingerprint, "synced_at": time.time()}
    if extra:
        data.update(extra)
    config.STATE_DIR.mkdir(parents=True, exist_ok=True)
    _sync_state_path().write_text(json.dumps(data), encoding="utf-8")


def pull_from_drive() -> dict:
    """`rclone sync <DRIVE_REMOTE> -> DOCS_DIR`. Fara remote configurat, e no-op."""
    remote = config.get("DRIVE_REMOTE")
    if not remote:
        return {"ok": True, "skipped": "DRIVE_REMOTE nesetat in env"}
    config.DOCS_DIR.mkdir(parents=True, exist_ok=True)
    try:
        r = subprocess.run(
            ["rclone", "sync", remote, str(config.DOCS_DIR)]
            + [arg for ext in store.DOC_EXTENSIONS for arg in ("--include", f"*{ext}")],
            capture_output=True, text=True, timeout=300,
        )
    except FileNotFoundError:
        return {"ok": False, "error": "rclone nu e instalat — vezi README.md"}
    except subprocess.TimeoutExpired:
        return {"ok": False, "error": "rclone a depasit timpul (300s)"}
    return {"ok": r.returncode == 0, "stdout": r.stdout[-2000:], "stderr": r.stderr[-2000:]}


def sync_and_reindex(force: bool = False) -> dict:
    pulled = pull_from_drive()
    fp = _fingerprint()
    last = read_sync_state().get("fingerprint")
    if not force and fp == last:
        return {"pulled": pulled, "reindexed": False, "reason": "fara schimbari"}
    result = indexer.build()
    _write_state(fp, {"last_build": result})
    return {"pulled": pulled, "reindexed": True, "build": result}


if __name__ == "__main__":
    try:
        with config.exclusive():
            out = sync_and_reindex(force="--force" in sys.argv[1:])
    except config.Busy as exc:
        out = {"skipped": str(exc)}
    print(json.dumps(out, ensure_ascii=False), file=sys.stderr)