# history_widget.py

import threading
import musicbrainzngs
from mutagen import File as MutagenFile
from PySide6.QtWidgets import (
    QFrame, QVBoxLayout, QLabel,
    QScrollArea, QWidget
)
from PySide6.QtCore import Qt, Signal
from PySide6.QtGui import QFont

musicbrainzngs.set_useragent("RadioPanel", "1.0", "radio@panel.local")


def _read_file_tags(filepath: str) -> dict:
    try:
        tags = MutagenFile(filepath, easy=True)
        if tags is None:
            return {}

        def get(key):
            val = tags.get(key)
            return val[0] if val else None

        return {
            'artist': get('artist'),
            'title':  get('title'),
            'album':  get('album'),
            'year':   get('date'),
        }
    except Exception:
        return {}


def _lookup_musicbrainz(artist: str, title: str) -> dict:
    try:
        result = musicbrainzngs.search_recordings(
            recording=title,
            artist=artist,
            limit=1
        )
        recordings = result.get('recording-list', [])
        if not recordings:
            return {}

        rec      = recordings[0]
        releases = rec.get('release-list', [])
        if not releases:
            return {}

        release = releases[0]
        album   = release.get('title', None)
        year    = None

        date = release.get('date', '')
        if date:
            year = date[:4]

        return {'album': album, 'year': year}
    except Exception:
        return {}


class HistoryEntry(QFrame):
    def __init__(self, index: int, filepath: str, metadata: dict, parent=None):
        super().__init__(parent)

        self.setFrameStyle(QFrame.Box)
        self.setStyleSheet("""
            QFrame {
                background-color: #1a1a1a;
                border: none;
                border-bottom: 1px solid #2a2a2a;
            }
        """)

        layout = QVBoxLayout(self)
        layout.setContentsMargins(8, 6, 8, 6)
        layout.setSpacing(2)

        artist = metadata.get('artist') or 'Unknown Artist'
        title  = metadata.get('title')  or self._filename(filepath)

        top_row = QLabel(f"{index}. {artist} — {title}")
        top_row.setFont(QFont("Arial", 11, QFont.Bold))
        top_row.setStyleSheet("color: #00ff41; background: transparent; border: none;")
        top_row.setWordWrap(True)
        layout.addWidget(top_row)

        album = metadata.get('album') or ''
        year  = metadata.get('year')  or ''

        sub_parts = []
        if album:
            sub_parts.append(album)
        if year:
            sub_parts.append(year[:4])

        if sub_parts:
            sub_row = QLabel("  " + "  ·  ".join(sub_parts))
            sub_row.setFont(QFont("Arial", 9))
            sub_row.setStyleSheet(
                "color: #888888; background: transparent; border: none;"
            )
            sub_row.setWordWrap(True)
            layout.addWidget(sub_row)

    def _filename(self, filepath: str) -> str:
        import os
        name = os.path.basename(filepath)
        return os.path.splitext(name)[0]


class HistoryWidget(QFrame):
    _metadata_ready = Signal(str, dict)

    def __init__(self, parent=None):
        super().__init__(parent)

        self._history = []
        self._pending = {}

        self.setFrameStyle(QFrame.Box | QFrame.Raised)
        self.setStyleSheet("""
            QFrame {
                background-color: #111111;
                border: 2px solid #336633;
                border-radius: 6px;
            }
        """)

        self._build_ui()
        self._metadata_ready.connect(self._on_metadata_ready)

    def _build_ui(self):
        root = QVBoxLayout(self)
        root.setContentsMargins(8, 8, 8, 8)
        root.setSpacing(6)

        header = QLabel("PLAY HISTORY")
        header.setFont(QFont("Arial", 11, QFont.Bold))
        header.setStyleSheet("""
            color: #336633;
            background: transparent;
            border: none;
            padding: 2px;
        """)
        header.setAlignment(Qt.AlignCenter)
        root.addWidget(header)

        self.scroll = QScrollArea()
        self.scroll.setWidgetResizable(True)
        self.scroll.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
        self.scroll.setStyleSheet("""
            QScrollArea {
                border: none;
                background: transparent;
            }
            QScrollBar:vertical {
                background: #1a1a1a;
                width: 8px;
                border-radius: 4px;
            }
            QScrollBar::handle:vertical {
                background: #336633;
                border-radius: 4px;
            }
        """)

        self.list_widget = QWidget()
        self.list_widget.setStyleSheet("background: transparent;")
        self.list_layout = QVBoxLayout(self.list_widget)
        self.list_layout.setContentsMargins(0, 0, 0, 0)
        self.list_layout.setSpacing(0)
        self.list_layout.addStretch()

        self.scroll.setWidget(self.list_widget)
        root.addWidget(self.scroll)

    def add_track(self, filepath: str):
        index    = len(self._history) + 1
        metadata = _read_file_tags(filepath)
        self._history.append((filepath, metadata))
        self._insert_entry(index, filepath, metadata)

        if not metadata.get('artist') or not metadata.get('album'):
            self._pending[filepath] = index
            threading.Thread(
                target=self._enrich_metadata,
                args=(filepath, metadata),
                daemon=True
            ).start()

    def _insert_entry(self, index: int, filepath: str, metadata: dict):
        entry = HistoryEntry(index, filepath, metadata)
        self.list_layout.insertWidget(0, entry)
        self.scroll.verticalScrollBar().setValue(0)

    def _enrich_metadata(self, filepath: str, existing: dict):
        artist = existing.get('artist')
        title  = existing.get('title')

        if not artist or not title:
            return

        mb_data = _lookup_musicbrainz(artist, title)
        if not mb_data:
            return

        merged = dict(existing)
        if not merged.get('album') and mb_data.get('album'):
            merged['album'] = mb_data['album']
        if not merged.get('year') and mb_data.get('year'):
            merged['year'] = mb_data['year']

        self._metadata_ready.emit(filepath, merged)

    def _on_metadata_ready(self, filepath: str, metadata: dict):
        for i, (fp, _) in enumerate(self._history):
            if fp == filepath:
                self._history[i] = (fp, metadata)
                break
        self._rebuild_list()

    def _rebuild_list(self):
        while self.list_layout.count() > 1:
            item = self.list_layout.takeAt(0)
            if item.widget():
                item.widget().deleteLater()

        for i, (filepath, metadata) in enumerate(reversed(self._history)):
            index = len(self._history) - i
            entry = HistoryEntry(index, filepath, metadata)
            self.list_layout.insertWidget(
                self.list_layout.count() - 1,
                entry
            )