"""
scan_worker.py — Kører fuld biblioteks-scanning i en baggrundstråd
så GUI ikke fryser.
"""

from PyQt6.QtCore import QThread, pyqtSignal


class ScanWorker(QThread):
    """
    Kører _full_scan_all() i en baggrundstråd.
    Sender status-opdateringer undervejs.
    """
    status_update = pyqtSignal(str)    # løbende statusbeskeder
    scan_done     = pyqtSignal(int)    # antal behandlede filer

    def __init__(self, watcher, parent=None):
        super().__init__(parent)
        self._watcher = watcher
        self._total = 0

    def run(self):
        try:
            from local.local_db import get_libraries
            libraries = get_libraries(active_only=True)

            if not libraries:
                self.status_update.emit("Ingen biblioteker konfigureret")
                self.scan_done.emit(0)
                return

            total_processed = 0
            for lib in libraries:
                from pathlib import Path
                path = Path(lib["path"])
                name = path.name
                self.status_update.emit(f"Scanner: {name}...")

                # Tæl filer først så vi kan vise fremgang
                from local.tag_reader import is_supported
                files = [f for f in path.rglob("*") if f.is_file() and is_supported(f)]
                count = len(files)
                self.status_update.emit(f"Scanner: {name} ({count} filer)...")

                # Kør scanning
                self._watcher._full_scan_library(lib["id"], str(path))
                total_processed += count

            self.status_update.emit(f"Scan færdig — {total_processed} filer gennemgået")
            self.scan_done.emit(total_processed)

        except Exception as e:
            self.status_update.emit(f"Scan fejl: {e}")
            self.scan_done.emit(0)