# backend/history.py
import json
import os
import time
import logging
import shutil
from pathlib import Path
from typing import List, Dict, Any, Optional

logger = logging.getLogger("obsigate.history")

HISTORY_DIR = Path("data/history")

def _get_history_file(username: str) -> Path:
    HISTORY_DIR.mkdir(parents=True, exist_ok=True)
    return HISTORY_DIR / f"{username}.json"

def _read_history(username: str) -> List[Dict[str, Any]]:
    h_file = _get_history_file(username)
    if not h_file.exists():
        return []
    try:
        return json.loads(h_file.read_text(encoding="utf-8"))
    except Exception as e:
        logger.error(f"Failed to read history for {username}: {e}")
        return []

def _write_history(username: str, history: List[Dict[str, Any]]):
    h_file = _get_history_file(username)
    try:
        tmp = h_file.with_suffix(".tmp")
        tmp.write_text(json.dumps(history, indent=2, ensure_ascii=False), encoding="utf-8")
        shutil.move(str(tmp), str(h_file))
    except Exception as e:
        logger.error(f"Failed to write history for {username}: {e}")

def record_open(username: str, vault: str, path: str, title: str = ""):
    """Record that a file was opened by a user."""
    if not username:
        return
    
    history = _read_history(username)
    
    # Remove existing entry for the same file if any
    history = [item for item in history if not (item["vault"] == vault and item["path"] == path)]
    
    # Add new entry at the beginning
    history.insert(0, {
        "vault": vault,
        "path": path,
        "title": title,
        "opened_at": time.time()
    })
    
    # Limit history size (e.g., 100 entries)
    history = history[:100]
    
    _write_history(username, history)

def get_recent_opened(username: str, vault_filter: Optional[str] = None, limit: int = 20) -> List[Dict[str, Any]]:
    """Get the most recently opened files for a user."""
    if not username:
        return []
        
    history = _read_history(username)
    
    if vault_filter:
        history = [item for item in history if item["vault"] == vault_filter]
        
    return history[:limit]