# backend/history.py
import json
import logging
import shutil
import time
from pathlib import Path
from typing import Any

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

def _read_data(file: Path) -> list[dict[str, Any]]:
    if not file.exists():
        return []
    try:
        return json.loads(file.read_text(encoding="utf-8"))
    except Exception as e:
        logger.error(f"Failed to read data from {file.name}: {e}")
        return []

def _write_data(file: Path, data: list[dict[str, Any]]):
    try:
        tmp = file.with_suffix(".tmp")
        tmp.write_text(json.dumps(data, indent=2, ensure_ascii=False), encoding="utf-8")
        shutil.move(str(tmp), str(file))
    except Exception as e:
        logger.error(f"Failed to write data to {file.name}: {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_data(_get_history_file(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_data(_get_history_file(username), history)

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

def remove_recent(username: str, vault: str, path: str):
    """Remove a file from the recent history (e.g., after deletion)."""
    if not username:
        return
    history = _read_data(_get_history_file(username))
    history = [item for item in history if not (item["vault"] == vault and item["path"] == path)]
    _write_data(_get_history_file(username), history)

def toggle_bookmark(username: str, vault: str, path: str, title: str = ""):
    """Toggle a file as bookmark for a user. Returns True if bookmarked, False if removed."""
    if not username:
        return False
        
    b_file = _get_bookmarks_file(username)
    bookmarks = _read_data(b_file)
    
    # Check if already bookmarked
    existing = [b for b in bookmarks if b["vault"] == vault and b["path"] == path]
    
    if existing:
        # Remove
        bookmarks = [b for b in bookmarks if not (b["vault"] == vault and b["path"] == path)]
        _write_data(b_file, bookmarks)
        return False
    else:
        # Add
        bookmarks.insert(0, {
            "vault": vault,
            "path": path,
            "title": title or path.split("/")[-1],
            "bookmarked_at": time.time()
        })
        _write_data(b_file, bookmarks)
        return True

def get_bookmarks(username: str, vault_filter: str | None = None) -> list[dict[str, Any]]:
    """Get the bookmarks for a user."""
    if not username:
        return []
    
    bookmarks = _read_data(_get_bookmarks_file(username))
    
    if vault_filter:
        bookmarks = [b for b in bookmarks if b["vault"] == vault_filter]
        
    return bookmarks

def is_bookmarked(username: str, vault: str, path: str) -> bool:
    """Fast check if a file is bookmarked by a user."""
    if not username:
        return False
    bookmarks = _read_data(_get_bookmarks_file(username))
    return any(b["vault"] == vault and b["path"] == path for b in bookmarks)


def update_bookmarks_after_rename(vault: str, old_path: str, new_path: str):
    """Update all users' bookmarks when a file is renamed."""
    if not HISTORY_DIR.exists():
        return
    for bfile in HISTORY_DIR.glob("*_bookmarks.json"):
        try:
            bookmarks = _read_data(bfile)
            updated = False
            for b in bookmarks:
                if b.get("vault") == vault and b.get("path") == old_path:
                    b["path"] = new_path
                    # Update title from new path
                    new_title = new_path.split("/")[-1].replace(".md", "").replace("-", " ").replace("_", " ")
                    b["title"] = new_title
                    updated = True
            if updated:
                _write_data(bfile, bookmarks)
                logger.info(f"Updated bookmarks in {bfile.name}: {vault}/{old_path} -> {new_path}")
        except Exception as e:
            logger.error(f"Failed to update bookmarks in {bfile.name}: {e}")


def update_history_after_rename(vault: str, old_path: str, new_path: str):
    """Update all users' history entries when a file is renamed."""
    if not HISTORY_DIR.exists():
        return
    for hfile in HISTORY_DIR.glob("*.json"):
        if "_bookmarks" in hfile.name:
            continue
        try:
            history = _read_data(hfile)
            updated = False
            for h in history:
                if h.get("vault") == vault and h.get("path") == old_path:
                    h["path"] = new_path
                    updated = True
            if updated:
                _write_data(hfile, history)
                logger.info(f"Updated history in {hfile.name}: {vault}/{old_path} -> {new_path}")
        except Exception as e:
            logger.error(f"Failed to update history in {hfile.name}: {e}")