import os
import time
import json
import tempfile
import shutil
from huggingface_hub import HfApi, hf_hub_download

HF_TOKEN = os.getenv("HF_TOKEN")
DATASET_ID = os.getenv("DATASET_ID") # e.g. "username/grim-fable-data"

api = HfApi(token=HF_TOKEN)

MANIFEST_FILE = "manifest.json"

# In-memory manifest cache to reduce API calls
_manifest_cache = {"data": None, "last_fetch": 0}
MANIFEST_CACHE_TTL = 30 # seconds

def get_manifest(force_refresh: bool = False):
    """Downloads and reads the manifest.json file with caching."""
    if not HF_TOKEN or not DATASET_ID:
        return {"saves": {}}

    now = time.time()
    if not force_refresh and _manifest_cache["data"] and (now - _manifest_cache["last_fetch"] < MANIFEST_CACHE_TTL):
        return _manifest_cache["data"]

    try:
        downloaded_path = hf_hub_download(
            repo_id=DATASET_ID,
            filename=MANIFEST_FILE,
            repo_type="dataset",
            token=HF_TOKEN
        )
        with open(downloaded_path, 'r') as f:
            data = json.load(f)
            _manifest_cache["data"] = data
            _manifest_cache["last_fetch"] = now
            return data
    except Exception as e:
        print(f"Notice: manifest.json not found or could not be read: {e}")
        return {"saves": {}}

def update_manifest(save_name: str, description: str = None, deleted: bool = False):
    """Updates the manifest.json with new/updated save info."""
    if not HF_TOKEN or not DATASET_ID:
        return

    manifest = get_manifest()
    if "saves" not in manifest: manifest["saves"] = {}

    if deleted:
        if save_name in manifest["saves"]:
            del manifest["saves"][save_name]
    else:
        existing = manifest["saves"].get(save_name, {"description": "", "timestamp": 0})
        manifest["saves"][save_name] = {
            "description": description if description is not None else existing["description"],
            "timestamp": time.time()
        }

    try:
        with tempfile.NamedTemporaryFile(mode='w', delete=False) as tf:
            json.dump(manifest, tf)
            temp_path = tf.name

        api.upload_file(
            path_or_fileobj=temp_path,
            path_in_repo=MANIFEST_FILE,
            repo_id=DATASET_ID,
            repo_type="dataset"
        )
        os.remove(temp_path)
        # Invalidate cache
        _manifest_cache["data"] = None
    except Exception as e:
        print(f"Error updating manifest: {e}")

def save_to_dataset(save_name: str, db_path: str, description: str = None):
    if not HF_TOKEN or not DATASET_ID:
        return False

    try:
        api.upload_file(
            path_or_fileobj=db_path,
            path_in_repo=f"{save_name}/world.db",
            repo_id=DATASET_ID,
            repo_type="dataset"
        )
        update_manifest(save_name, description)
        return True
    except Exception as e:
        print(f"Error saving to dataset: {e}")
        return False

def load_from_dataset(save_name: str, db_path: str):
    if not HF_TOKEN or not DATASET_ID:
        return False

    path_in_repo = f"{save_name}/world.db"
    try:
        downloaded_path = hf_hub_download(
            repo_id=DATASET_ID,
            filename=path_in_repo,
            repo_type="dataset",
            token=HF_TOKEN
        )
        shutil.copy(downloaded_path, db_path)
        return True
    except Exception as e:
        print(f"Error loading from dataset: {e}")
        return False

def delete_save(save_name: str):
    if not HF_TOKEN or not DATASET_ID:
        return False

    try:
        update_manifest(save_name, deleted=True)
        files = api.list_repo_files(repo_id=DATASET_ID, repo_type="dataset")
        files_to_delete = [f for f in files if f.startswith(f"{save_name}/")]
        for f in files_to_delete:
            api.delete_file(path_in_repo=f, repo_id=DATASET_ID, repo_type="dataset")
        return True
    except Exception as e:
        print(f"Error deleting save: {e}")
        return False

def list_saves():
    if not HF_TOKEN or not DATASET_ID:
        return []
    manifest = get_manifest()
    results = []
    for name, data in manifest.get("saves", {}).items():
        results.append({
            "name": name,
            "description": data.get("description", ""),
            "timestamp": data.get("timestamp", 0)
        })
    return results

def get_cached_media(save_name: str, entity_id: str, media_type: str):
    """Retrieves media content from the dataset if it exists."""
    ext = "webp" if media_type == "image" else "mp3"
    path_in_repo = f"{save_name}/media/{entity_id}.{ext}"
    try:
        downloaded_path = hf_hub_download(
            repo_id=DATASET_ID,
            filename=path_in_repo,
            repo_type="dataset",
            token=HF_TOKEN
        )
        with open(downloaded_path, 'rb') as f:
            return f.read()
    except Exception:
        return None

def save_cached_media(save_name: str, entity_id: str, media_type: str, content: bytes):
    """Saves media content to the dataset."""
    ext = "webp" if media_type == "image" else "mp3"
    path_in_repo = f"{save_name}/media/{entity_id}.{ext}"
    try:
        with tempfile.NamedTemporaryFile(mode='wb', delete=False) as tf:
            tf.write(content)
            temp_path = tf.name

        api.upload_file(
            path_or_fileobj=temp_path,
            path_in_repo=path_in_repo,
            repo_id=DATASET_ID,
            repo_type="dataset"
        )
        os.remove(temp_path)
        return True
    except Exception as e:
        print(f"Error caching media: {e}")
        return False

class PersistenceLoop:
    def __init__(self):
        self.last_interaction_time = time.time()
        self.last_save_time = time.time()
        self.current_save_name = "default_save"
        self.needs_save = False
        self.turn_counter = 0

    def update_interaction(self):
        self.last_interaction_time = time.time()
        self.needs_save = True
        self.turn_counter += 1

    def should_autosave(self, interaction_happened=False):
        now = time.time()

        # Immediate save every 5 turns
        if interaction_happened and self.turn_counter >= 5:
            self.turn_counter = 0
            return True

        # If an interaction just happened, we don't save immediately unless it's been a long time (safety check)
        if interaction_happened:
            if now - self.last_save_time > 3600 and self.needs_save: return True
            return False

        # Idle save: trigger if we have unsaved changes and it's been 30 mins since last interaction
        if self.needs_save and now - self.last_interaction_time > 1800:
             return True

        return False

persistence_manager = PersistenceLoop()