import os
import requests
from typing import List, Dict, Optional

MUSICBRAINZ_USER_AGENT = os.getenv("MUSICBRAINZ_USER_AGENT", "MusicApp/1.0")
MUSICBRAINZ_URL = "https://musicbrainz.org/ws/2/"


def search_artist(artist_name: str) -> Optional[Dict]:
    try:
        url = f"{MUSICBRAINZ_URL}artist"
        params = {
            "query": artist_name,
            "fmt": "json",
            "limit": 1,
        }
        headers = {"User-Agent": MUSICBRAINZ_USER_AGENT}
        
        response = requests.get(url, params=params, headers=headers, timeout=10)
        if response.status_code != 200:
            return None
        
        data = response.json()
        artists = data.get("artists", [])
        if artists:
            a = artists[0]
            return {
                "id": a.get("id"),
                "name": a.get("name"),
                "releases": [],
            }
        return None
    except (requests.RequestException, KeyError):
        return None


def get_artist_releases(artist_id: str, limit: int = 10) -> List[Dict]:
    try:
        url = f"{MUSICBRAINZ_URL}artist/{artist_id}/releases"
        params = {
            "inc": "recordings+labels+artists",
            "fmt": "json",
            "limit": limit,
            "order": "date",
        }
        headers = {"User-Agent": MUSICBRAINZ_USER_AGENT}
        
        response = requests.get(url, params=params, headers=headers, timeout=10)
        if response.status_code != 200:
            return []
        
        data = response.json()
        releases = data.get("releases", [])
        
        result = []
        for rel in releases:
            recordings = rel.get("media", [{}])[0].get("tracks", []) if rel.get("media") else []
            tracks = []
            for rec in recordings:
                tracks.append({
                    "title": rec.get("title", "Unknown"),
                    "duration": int(rec.get("length", 0)) / 1000 if rec.get("length") else 0,
                    "duration_formatted": _format_duration(int(rec.get("length", 0)) / 1000),
                })
            
            result.append({
                "id": rel.get("id"),
                "title": rel.get("title", "Unknown"),
                "cover_art": None,
                "release_date": rel.get("date", ""),
                "tracks": tracks,
            })
        
        return result
    except (requests.RequestException, KeyError, IndexError):
        return []


def _format_duration(seconds: float) -> str:
    m = int(seconds // 60)
    s = int(seconds % 60)
    return f"{m}:{s:02d}"