"Internal" Metadata Support Plugin

vimiv/plugins/metadata_general.py

@@ -0,0 +1,108 @@
+# vim: ft=python fileencoding=utf-8 sw=4 et sts=4
+
+# This file is part of vimiv.
+# Copyright 2017-2023 Christian Karl (karlch) <karlch at protonmail dot com>
+# License: GNU GPL v3, see the "LICENSE" and "AUTHORS" files for details.
+
+"""Metadata plugin provides all sort of information not provided by EXIF, IPTC, or XMP.
+
+Properties:
+- Get data not present in Exif, ICMP or XMP.
+"""
+
+import contextlib
+from typing import Any, Sequence, Iterable, Optional, Dict, Tuple, Callable
+
+from PyQt5.QtGui import QImageReader
+
+from vimiv.imutils import metadata
+from vimiv.utils import log, files
+
+_logger = log.module_logger(__name__)
+
+
+class MetadataGeneral(metadata.MetadataPlugin):
+    """Provides all sort of information not provided by EXIF, IPTC, or XMP.
+
+    Implements `get_metadata`, and `get_keys` only.
+    """
+
+    def __init__(self, path: str) -> None:
+        self._path = path
+        self._reader: Optional[QImageReader] = None
+
+        # For each key, store (description, function)
+        self._registry: Dict[str, Tuple[str, Callable]] = {
+            "Vimiv.FileSize": ("File Size", self._get_filesize),
+            "Vimiv.XDimension": (
+                "Pixel X Dimension",
+                self._get_xdimension,
+            ),
+            "Vimiv.YDimension": (
+                "Pixel Y Dimension",
+                self._get_ydimension,
+            ),
+            "Vimiv.FileType": ("File Type", self._get_filetype),
+        }
+
+    @staticmethod
+    def name() -> str:
+        """No backend is used, return plugin name."""
+        return "general"
+
+    @staticmethod
+    def version() -> str:
+        """No backend used, return empty string."""
+        return ""
+
+    @property
+    def reader(self) -> QImageReader:
+        """Return QImageReader instance of _path."""
+        if self._reader is None:
+            self._reader = QImageReader(self._path)
+        return self._reader
+
+    def get_metadata(self, desired_keys: Sequence[str]) -> metadata.MetadataDictT:
+        """Get value of all desired keys for the current image."""
+        out = {}
+
+        for key in desired_keys:
+            with contextlib.suppress(KeyError):
+                desc, func = self._registry[key]
+                out[key] = (desc, func())
+
+        return out
+
+    def get_keys(self) -> Iterable[str]:
+        """Get the keys for all metadata values available for the current image."""
+        return self._registry.keys()
+
+    def _get_filesize(self) -> str:
+        """Get the file size."""
+        return files.get_size_file(self._path)
+
+    def _get_filetype(self) -> str:
+        """Get the file type."""
+        out = files.imghdr.what(self._path)
+        if out:
+            return out
+        return ""
+
+    def _get_xdimension(self) -> str:
+        """Get the x dimension in pixels.
+
+        Does only works for image formats supported by QT natively.
+        """
+        return str(self.reader.size().width())
+
+    def _get_ydimension(self) -> str:
+        """Get the y dimension in pixels.
+
+        Does only works for image formats supported by QT natively.
+        """
+        return str(self.reader.size().height())
+
+
+def init(*_args: Any, **_kwargs: Any) -> None:
+    """Register `MetadataGeneral` as a metadata handler."""
+    metadata.register(MetadataGeneral)