# utils/activities.py
"""
Mood-based Discord activity status system.

Loads activity definitions from activities.yaml and provides functions to:
- Pick a weighted-random activity for a given mood
- Update the bot's Discord presence (Listening/Playing)
- Get/set activity data for the Web UI
"""

import os
import random
import yaml
import discord
import globals
from utils.logger import get_logger

logger = get_logger('activity')

ACTIVITIES_FILE = os.path.join(os.path.dirname(os.path.dirname(__file__)), "activities.yaml")

# Cache: (data_dict, file_mtime)
_activities_cache = None
_cache_mtime = 0.0


def _load_activities(force=False):
    """Load activities.yaml with file-mtime-based caching.
    
    Returns the full dict: {"normal": {...}, "evil": {...}}
    """
    global _activities_cache, _cache_mtime

    try:
        mtime = os.path.getmtime(ACTIVITIES_FILE)
    except OSError:
        logger.warning(f"Activities file not found: {ACTIVITIES_FILE}")
        return {"normal": {}, "evil": {}}

    if not force and _activities_cache is not None and mtime == _cache_mtime:
        return _activities_cache

    try:
        with open(ACTIVITIES_FILE, "r", encoding="utf-8") as f:
            data = yaml.safe_load(f) or {}
        _activities_cache = data
        _cache_mtime = mtime
        logger.debug(f"Loaded activities from {ACTIVITIES_FILE}")
        return data
    except Exception as e:
        logger.error(f"Failed to load activities file: {e}")
        return _activities_cache or {"normal": {}, "evil": {}}


def save_activities(data: dict):
    """Write the full activities dict back to YAML."""
    global _activities_cache, _cache_mtime

    try:
        with open(ACTIVITIES_FILE, "w", encoding="utf-8") as f:
            yaml.dump(data, f, default_flow_style=False, allow_unicode=True, sort_keys=False)

        # Update cache immediately
        _activities_cache = data
        _cache_mtime = os.path.getmtime(ACTIVITIES_FILE)
        logger.info(f"Saved activities to {ACTIVITIES_FILE}")
    except Exception as e:
        logger.error(f"Failed to save activities file: {e}")
        raise


def get_all_activities() -> dict:
    """Return the full activities dict (normal + evil sections)."""
    return _load_activities()


def get_activities_for_mood(mood_name: str, is_evil: bool = False) -> list:
    """Return the activity list for a specific mood. Returns empty list if not found."""
    section = "evil" if is_evil else "normal"
    data = _load_activities()
    return data.get(section, {}).get(mood_name, [])


def set_activities_for_mood(mood_name: str, is_evil: bool, activities: list):
    """Validate and save updated activity list for a mood.
    
    Args:
        mood_name: mood key (e.g. "bubbly", "aggressive")
        is_evil: True for evil section, False for normal
        activities: list of dicts with keys {type, name, weight}
    
    Raises:
        ValueError: if validation fails
    """
    # Validate
    valid_types = {"listening", "playing"}
    for i, entry in enumerate(activities):
        if not isinstance(entry, dict):
            raise ValueError(f"Entry {i} must be a dict, got {type(entry).__name__}")
        if entry.get("type") not in valid_types:
            raise ValueError(f"Entry {i} has invalid type '{entry.get('type')}', must be 'listening' or 'playing'")
        if not entry.get("name") or not isinstance(entry["name"], str):
            raise ValueError(f"Entry {i} must have a non-empty string 'name'")
        if not isinstance(entry.get("weight", 0), int) or entry.get("weight", 0) < 1:
            raise ValueError(f"Entry {i} weight must be a positive integer")

    section = "evil" if is_evil else "normal"
    data = _load_activities()
    if section not in data:
        data[section] = {}
    data[section][mood_name] = activities
    save_activities(data)


def pick_activity_for_mood(mood_name: str, is_evil: bool = False):
    """Pick a weighted-random activity for a mood.
    
    Returns:
        tuple: (activity_type, name) e.g. ("listening", "World is Mine")
               Returns ("listening", "Vocaloid") as fallback if mood has no entries.
    """
    activities = get_activities_for_mood(mood_name, is_evil)

    if not activities:
        logger.debug(f"No activities defined for {'evil/' if is_evil else ''}{mood_name}, using fallback")
        return ("listening", "Vocaloid")

    # Weighted random selection
    weights = [entry.get("weight", 1) for entry in activities]
    chosen = random.choices(activities, weights=weights, k=1)[0]
    return (chosen["type"], chosen["name"])


async def update_bot_presence(mood_name: str, is_evil: bool = False):
    """Update the bot's Discord presence based on the current mood.
    
    - asleep: shows idle status, no activity
    - Other moods: shows "Listening to..." or "Playing..." with weighted-random pick
    """
    if not globals.client or not globals.client.is_ready():
        logger.debug("Bot not ready, skipping presence update")
        return

    try:
        if mood_name == "asleep":
            # While asleep: idle status, no activity
            await globals.client.change_presence(
                status=discord.Status.idle,
                activity=None
            )
            logger.info("Set presence: idle (asleep)")
            return

        activity_type, name = pick_activity_for_mood(mood_name, is_evil)

        if activity_type == "listening":
            activity = discord.Activity(type=discord.ActivityType.listening, name=name)
            log_label = f"Listening to {name}"
        else:
            activity = discord.Game(name=name)
            log_label = f"Playing {name}"

        await globals.client.change_presence(activity=activity)
        logger.info(f"Set presence: {log_label} (mood={'evil/' if is_evil else ''}{mood_name})")

    except Exception as e:
        logger.error(f"Failed to update bot presence: {e}")


async def clear_bot_presence():
    """Clear the bot's activity (set to online with no activity)."""
    if not globals.client or not globals.client.is_ready():
        return
    try:
        await globals.client.change_presence(status=discord.Status.online, activity=None)
        logger.info("Cleared bot presence")
    except Exception as e:
        logger.error(f"Failed to clear bot presence: {e}")