from __future__ import annotations

import os
import sys
import time
from typing import Optional, List, Dict, Tuple

from models import AlbumHints, AlbumProposal, TrackProposal

try:
    import musicbrainzngs as mb
    mb.set_useragent("MusicMetadataEnricher", "1.0", "https://github.com/dschlueter")
    HAS_MB = True
except ImportError:
    HAS_MB = False

try:
    import acoustid
    HAS_ACOUSTID = True
except ImportError:
    HAS_ACOUSTID = False

try:
    import discogs_client as dc
    HAS_DISCOGS = True
except ImportError:
    HAS_DISCOGS = False

try:
    import anthropic
    HAS_ANTHROPIC = True
except ImportError:
    HAS_ANTHROPIC = False

_MB_RATE_LIMIT = 1.1   # seconds between MusicBrainz requests
_last_mb_call = 0.0
ACOUSTID_API_KEY  = os.getenv("ACOUSTID_API_KEY", "")
ANTHROPIC_API_KEY = os.getenv("ANTHROPIC_API_KEY", "")
OPENROUTER_API_KEY = os.getenv("OPENROUTER_API_KEY", "")
DISCOGS_TOKEN     = os.getenv("DISCOGS_TOKEN", "")
OLLAMA_HOST       = os.getenv("OLLAMA_HOST", "http://localhost:11434")

# Lokales Reasoning-Modell für Metadaten-Ergänzung (passt auf RTX 3090)
OLLAMA_RESOLVE_MODEL = os.getenv("OLLAMA_RESOLVE_MODEL", "qwen3.5:27b")


def _mb_wait():
    global _last_mb_call
    elapsed = time.monotonic() - _last_mb_call
    if elapsed < _MB_RATE_LIMIT:
        time.sleep(_MB_RATE_LIMIT - elapsed)
    _last_mb_call = time.monotonic()


# ---------------------------------------------------------------------------
# AcoustID fingerprinting
# ---------------------------------------------------------------------------

def _fingerprint_tracks(hints: AlbumHints) -> Dict[str, List[str]]:
    """Returns {audio_path_str: [mbid, ...]}"""
    if not HAS_ACOUSTID or not ACOUSTID_API_KEY:
        return {}
    results: Dict[str, List[str]] = {}
    for t in hints.tracks:
        try:
            duration, fp = acoustid.fingerprint_file(str(t.path))
            response = acoustid.lookup(ACOUSTID_API_KEY, fp, duration,
                                       meta="recordings releasegroups")
            mbids: List[str] = []
            for result in response.get("results", []):
                if result.get("score", 0) >= 0.90:
                    for rec in result.get("recordings", []):
                        mbids.append(rec["id"])
            results[str(t.path)] = mbids
        except Exception as e:
            print(f"  ⚠️ AcoustID-Fehler {t.path.name}: {e}", file=sys.stderr)
    return results


# ---------------------------------------------------------------------------
# MusicBrainz lookup
# ---------------------------------------------------------------------------

def _mb_search_release(artist: Optional[str], album: Optional[str],
                        year: Optional[str]) -> Optional[Dict]:
    if not HAS_MB or (not artist and not album):
        return None
    query_parts = []
    if album:
        query_parts.append(f'release:"{album}"')
    if artist:
        query_parts.append(f'artist:"{artist}"')
    if year:
        query_parts.append(f'date:{year}')
    query = " AND ".join(query_parts)
    try:
        _mb_wait()
        result = mb.search_releases(query=query, limit=3)
        releases = result.get("release-list", [])
        if not releases:
            return None
        # Take highest-score release
        best = max(releases, key=lambda r: int(r.get("ext:score", 0)))
        score = int(best.get("ext:score", 0))
        if score < 70:
            return None
        return best
    except Exception as e:
        print(f"  ⚠️ MusicBrainz-Suchfehler: {e}", file=sys.stderr)
        return None


def _mb_get_release_tracks(release_id: str) -> Optional[List[Dict]]:
    if not HAS_MB:
        return None
    try:
        _mb_wait()
        result = mb.get_release_by_id(
            release_id,
            includes=["recordings", "artist-credits", "labels", "release-groups"],
        )
        return result.get("release")
    except Exception as e:
        print(f"  ⚠️ MusicBrainz-Release-Fehler: {e}", file=sys.stderr)
        return None


def _mb_recording_to_release(recording_mbid: str) -> Optional[Dict]:
    if not HAS_MB:
        return None
    try:
        _mb_wait()
        result = mb.get_recording_by_id(
            recording_mbid,
            includes=["releases", "artist-credits", "release-groups"],
        )
        rec = result.get("recording", {})
        releases = rec.get("release-list", [])
        if releases:
            return releases[0]
        return None
    except Exception as e:
        print(f"  ⚠️ MusicBrainz-Recording-Fehler: {e}", file=sys.stderr)
        return None


# ---------------------------------------------------------------------------
# Discogs fallback
# ---------------------------------------------------------------------------

def _discogs_search(artist: Optional[str], album: Optional[str]) -> Optional[Dict]:
    if not HAS_DISCOGS or not DISCOGS_TOKEN:
        return None
    try:
        client = dc.Client("MusicMetadataEnricher/1.0", user_token=DISCOGS_TOKEN)
        results = client.search(
            album or artist or "",
            artist=artist or "",
            type="release",
        )
        if results.count:
            r = results[0]
            return {
                "album": r.title,
                "artist": r.artists[0].name if r.artists else None,
                "year": str(r.year) if r.year else None,
                "genre": r.genres[0] if r.genres else None,
                "label": r.labels[0].name if r.labels else None,
                "id": r.id,
            }
    except Exception as e:
        print(f"  ⚠️ Discogs-Fehler: {e}", file=sys.stderr)
    return None


# ---------------------------------------------------------------------------
# Claude API reasoning (optional)
# ---------------------------------------------------------------------------

def _build_resolve_prompt(hints: AlbumHints, partial: Dict) -> str:
    tracks_summary = "\n".join(
        f"  - Track {t.track_number or '?'}: {t.title or t.path.stem}"
        + (f" [{t.artist}]" if t.artist else "")
        for t in hints.tracks[:20]
    )
    return (
        "Du bist ein Musikexperte. Analysiere diese Album-Daten und vervollständige die fehlenden Felder.\n\n"
        f"Verzeichnisname: {hints.album_dir.name}\n"
        f"Bekannte Artist: {hints.dir_artist or partial.get('artist', 'unbekannt')}\n"
        f"Bekannter Albumtitel: {hints.dir_album or partial.get('album', 'unbekannt')}\n"
        f"Jahr: {hints.dir_year or partial.get('year', 'unbekannt')}\n"
        f"Tracklist-Hinweise:\n{tracks_summary}\n\n"
        'Antworte NUR mit einem JSON-Objekt mit diesen Feldern (null wenn unbekannt):\n'
        '{"artist": ..., "album": ..., "albumartist": ..., "year": ..., "genre": ..., "label": ...}'
    )


def _parse_json_response(text: str) -> Optional[Dict]:
    import json, re
    m = re.search(r"\{.*\}", text, re.DOTALL)
    if m:
        try:
            return json.loads(m.group())
        except Exception:
            pass
    return None


def _resolve_via_ollama(hints: AlbumHints, partial: Dict) -> Optional[Dict]:
    """Lokales Reasoning via Ollama (kein API-Key nötig)."""
    import urllib.request, json
    prompt = _build_resolve_prompt(hints, partial)
    payload = json.dumps({
        "model": OLLAMA_RESOLVE_MODEL,
        "messages": [{"role": "user", "content": prompt}],
        "stream": False,
        "format": "json",
        "options": {"temperature": 0.1},
    }).encode()
    try:
        req = urllib.request.Request(
            f"{OLLAMA_HOST}/api/chat",
            data=payload,
            headers={"Content-Type": "application/json"},
            method="POST",
        )
        with urllib.request.urlopen(req, timeout=120) as resp:
            data = json.loads(resp.read())
        text = data.get("message", {}).get("content", "").strip()
        return _parse_json_response(text)
    except Exception as e:
        print(f"  ⚠️ Ollama-Resolve-Fehler: {e}", file=sys.stderr)
    return None


def _resolve_via_openrouter(hints: AlbumHints, partial: Dict) -> Optional[Dict]:
    """Reasoning via OpenRouter (günstige chinesische Modelle bevorzugt)."""
    if not OPENROUTER_API_KEY:
        return None
    import urllib.request, json
    prompt = _build_resolve_prompt(hints, partial)
    # DeepSeek V3: extrem günstig, sehr kompetent
    model = "deepseek/deepseek-chat-v3-0324"
    payload = json.dumps({
        "model": model,
        "messages": [{"role": "user", "content": prompt}],
        "temperature": 0.1,
        "max_tokens": 300,
    }).encode()
    try:
        req = urllib.request.Request(
            "https://openrouter.ai/api/v1/chat/completions",
            data=payload,
            headers={
                "Content-Type": "application/json",
                "Authorization": f"Bearer {OPENROUTER_API_KEY}",
                "HTTP-Referer": "https://pi.local",
                "X-Title": "MusicMetadataEnricher",
            },
            method="POST",
        )
        with urllib.request.urlopen(req, timeout=30) as resp:
            data = json.loads(resp.read())
        text = data["choices"][0]["message"]["content"].strip()
        return _parse_json_response(text)
    except Exception as e:
        print(f"  ⚠️ OpenRouter-Resolve-Fehler: {e}", file=sys.stderr)
    return None


def _claude_resolve(hints: AlbumHints, partial: Dict) -> Optional[Dict]:
    """
    Reihenfolge: Ollama (lokal, kostenlos) → OpenRouter (günstig) → Claude API.
    Ollama wird versucht wenn OLLAMA_HOST erreichbar; kein Key nötig.
    """
    # 1. Ollama lokal (bevorzugt — kostenlos, RTX 3090)
    result = _resolve_via_ollama(hints, partial)
    if result:
        return result

    # 2. OpenRouter (DeepSeek V3, günstig) wenn Key gesetzt
    if OPENROUTER_API_KEY:
        result = _resolve_via_openrouter(hints, partial)
        if result:
            return result

    # 3. Claude API als letzter Fallback
    if not HAS_ANTHROPIC or not ANTHROPIC_API_KEY:
        return None
    try:
        client = anthropic.Anthropic(api_key=ANTHROPIC_API_KEY)
        prompt = _build_resolve_prompt(hints, partial)
        message = client.messages.create(
            model="claude-haiku-4-5-20251001",
            max_tokens=300,
            messages=[{"role": "user", "content": prompt}],
        )
        text = message.content[0].text.strip()
        return _parse_json_response(text)
    except Exception as e:
        print(f"  ⚠️ Claude-API-Fehler: {e}", file=sys.stderr)
    return None


# ---------------------------------------------------------------------------
# Main resolver
# ---------------------------------------------------------------------------

def resolve(
    hints: AlbumHints,
    use_fingerprint: bool = True,
    use_api: bool = True,
    use_claude: bool = True,
) -> AlbumProposal:
    confidence = 0.0
    sources: List[str] = []
    notes: List[str] = []

    artist = hints.dir_artist
    album = hints.dir_album
    year = hints.dir_year
    genre: Optional[str] = None
    label: Optional[str] = None
    release_mbid: Optional[str] = None
    mb_tracks: Optional[List] = None

    # Collect artist/album from existing tags (majority vote)
    tag_artists = [t.existing_tags.get("artist") for t in hints.tracks if t.existing_tags.get("artist")]
    tag_albums = [t.existing_tags.get("album") for t in hints.tracks if t.existing_tags.get("album")]
    if tag_artists:
        from collections import Counter
        artist = artist or Counter(tag_artists).most_common(1)[0][0]
    if tag_albums:
        from collections import Counter
        album = album or Counter(tag_albums).most_common(1)[0][0]

    # Tag year/genre/label
    for t in hints.tracks:
        year = year or t.existing_tags.get("date") or t.existing_tags.get("year")
        genre = genre or t.existing_tags.get("genre")
        label = label or t.existing_tags.get("label") or t.existing_tags.get("organization")

    if artist or album:
        confidence += 0.05
        sources.append("local-hints")

    # AcoustID fingerprinting
    fp_mbids: Dict[str, List[str]] = {}
    if use_fingerprint and use_api and HAS_ACOUSTID and ACOUSTID_API_KEY:
        fp_mbids = _fingerprint_tracks(hints)
        if fp_mbids:
            confidence += 0.20
            sources.append("acoustid")
            # Try to get release from first matched recording
            for mbids in fp_mbids.values():
                for mbid in mbids[:1]:
                    rel = _mb_recording_to_release(mbid)
                    if rel:
                        release_mbid = rel.get("id")
                        confidence += 0.25
                        sources.append("musicbrainz-fingerprint")
                        break
                if release_mbid:
                    break

    # MusicBrainz text search
    if use_api and HAS_MB and not release_mbid:
        mb_result = _mb_search_release(artist, album, year)
        if mb_result:
            release_mbid = mb_result.get("id")
            score = int(mb_result.get("ext:score", 0))
            confidence += 0.30 * (score / 100)
            sources.append("musicbrainz-text")
            notes.append(f"MusicBrainz score: {score}")

    # Fetch full release data
    if use_api and release_mbid:
        full_release = _mb_get_release_tracks(release_mbid)
        if full_release:
            if not artist:
                creds = full_release.get("artist-credit", [])
                artist = "".join(c.get("artist", {}).get("name", "") + c.get("joinphrase", "")
                                  for c in creds if isinstance(c, dict)).strip() or artist
            if not album:
                album = full_release.get("title", album)
            if not year:
                year = full_release.get("date", "")[:4] or None
            label_info = full_release.get("label-info-list", [])
            if label_info and not label:
                label = label_info[0].get("label", {}).get("name") if label_info else None
            rg = full_release.get("release-group", {})
            if not genre:
                genre = (rg.get("primary-type") or "").strip() or None
            mb_tracks = []
            for medium in full_release.get("medium-list", []):
                disc_num = medium.get("position", 1)
                for track in medium.get("track-list", []):
                    mb_tracks.append({
                        "disc": disc_num,
                        "number": int(track.get("number", 0) or 0),
                        "title": track.get("recording", {}).get("title", ""),
                        "artist": track.get("artist-credit-phrase", ""),
                        "mbid": track.get("recording", {}).get("id"),
                    })

    # Discogs fallback
    if use_api and HAS_DISCOGS and DISCOGS_TOKEN and not release_mbid:
        dg = _discogs_search(artist, album)
        if dg:
            artist = artist or dg.get("artist")
            album = album or dg.get("album")
            year = year or dg.get("year")
            genre = genre or dg.get("genre")
            label = label or dg.get("label")
            confidence += 0.15
            sources.append("discogs")

    # LLM-Reasoning für verbleibende Lücken:
    # Reihenfolge: Ollama lokal → OpenRouter (DeepSeek, günstig) → Claude API
    partial = {"artist": artist, "album": album, "year": year}
    if use_claude and use_api:
        if not artist or not album or confidence < 0.5:
            cl = _claude_resolve(hints, partial)
            if cl:
                artist = artist or cl.get("artist")
                album = album or cl.get("album")
                year = year or cl.get("year")
                genre = genre or cl.get("genre")
                label = label or cl.get("label")
                confidence += 0.10
                sources.append("llm-resolve")

    # Finalize albumartist
    track_artists = [t.artist for t in hints.tracks if t.artist]
    from collections import Counter
    distinct_artists = set(a for a in track_artists if a)
    if len(distinct_artists) >= 3:
        albumartist = "Various Artists"
    elif track_artists:
        albumartist = artist or Counter(track_artists).most_common(1)[0][0]
    else:
        albumartist = artist or "Unknown Artist"

    album = album or hints.album_dir.name.replace("_", " ")
    artist = artist or albumartist
    confidence = min(confidence, 1.0)

    # Build track proposals
    track_proposals = _build_track_proposals(hints, mb_tracks, album, artist)

    return AlbumProposal(
        album_dir=hints.album_dir,
        album=album,
        albumartist=albumartist,
        date=year,
        genre=genre,
        label=label,
        mbid=release_mbid,
        cover_path=None,
        cover_source=None,
        tracks=track_proposals,
        confidence=confidence,
        sources=sources,
        notes=notes,
    )


def _build_track_proposals(
    hints: AlbumHints,
    mb_tracks: Optional[List],
    album: str,
    album_artist: str,
) -> List[TrackProposal]:
    proposals: List[TrackProposal] = []

    for th in sorted(hints.tracks, key=lambda t: (t.disc_number or 1, t.track_number or 9999, str(t.path))):
        title = th.title
        artist = th.artist or album_artist
        track_num = th.track_number
        disc_num = th.disc_number

        # Try to match from MusicBrainz track list
        if mb_tracks and track_num:
            for mb_t in mb_tracks:
                if mb_t["number"] == track_num and mb_t["disc"] == (disc_num or 1):
                    if mb_t.get("title"):
                        title = mb_t["title"]
                    if mb_t.get("artist"):
                        artist = mb_t["artist"]
                    break

        title = title or th.path.stem

        proposals.append(TrackProposal(
            path=th.path,
            title=title,
            artist=artist,
            track_number=track_num,
            disc_number=disc_num,
            mbid=None,
        ))

    return proposals