[mod] typification of SearXNG: add new result type Paper

This patch adds a new result type: Paper

- Python class:   searx/result_types/paper.py
- Jinja template: searx/templates/simple/result_templates/paper.html
- CSS (less)      client/simple/src/less/result_types/paper.less

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

searx/result_types/__init__.py

@@ -22,6 +22,7 @@ __all__ = [
     "Translations",
     "WeatherAnswer",
     "Code",
+    "Paper",
 ]
 
 import typing as t
@@ -31,6 +32,7 @@ from ._base import Result, MainResult, LegacyResult
 from .answer import AnswerSet, Answer, Translations, WeatherAnswer
 from .keyvalue import KeyValue
 from .code import Code
+from .paper import Paper
 
 
 class ResultList(list[Result | LegacyResult], abc.ABC):
@@ -44,6 +46,7 @@ class ResultList(list[Result | LegacyResult], abc.ABC):
         Answer = Answer
         KeyValue = KeyValue
         Code = Code
+        Paper = Paper
         MainResult = MainResult
         Result = Result
         Translations = Translations

searx/result_types/_base.py

@@ -362,7 +362,11 @@ class MainResult(Result):  # pylint: disable=missing-class-docstring
     """The date on which the object was published."""
 
     pubdate: str = ""
-    """String representation of :py:obj:`MainResult.publishedDate`"""
+    """String representation of :py:obj:`MainResult.publishedDate`
+
+    Deprecated: it is still partially used in the templates, but will one day be
+    completely eliminated.
+    """
 
     length: time.struct_time | None = None
     """Playing duration in seconds."""

searx/result_types/paper.py

@@ -0,0 +1,96 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+"""Typification of the *paper* results.
+
+.. _BibTeX field types: https://en.wikipedia.org/wiki/BibTeX#Field_types
+.. _BibTeX format: https://www.bibtex.com/g/bibtex-format/
+
+Results of this type are rendered in the :origin:`paper.html
+<searx/templates/simple/result_templates/paper.html>` template.
+
+Related topics:
+
+- `BibTeX field types`_
+- `BibTeX format`_
+
+----
+
+.. autoclass:: Paper
+   :members:
+   :show-inheritance:
+
+"""
+# pylint: disable=too-few-public-methods, disable=invalid-name
+
+from __future__ import annotations
+
+__all__ = ["Paper"]
+
+import typing as t
+
+from searx.weather import DateTime
+from ._base import MainResult
+
+
+@t.final
+class Paper(MainResult, kw_only=True):
+    """Result type suitable for displaying scientific papers and other
+    documents."""
+
+    template: str = "paper.html"
+
+    date_of_publication: DateTime | None = None
+    """Date the document was published."""
+
+    content: str = ""
+    """An abstract or excerpt from the document."""
+
+    comments: str = ""
+    """Free text display in italic below the content."""
+
+    tags: list[str] = []
+    """Free tag list."""
+
+    type: str = ""
+    """Short description of medium type, e.g. *book*, *pdf* or *html* ..."""
+
+    authors: list[str] | set[str] = []
+    """List of authors of the work (authors with a "s" suffix, the "author" is
+    in the :py:obj:`MainResult.author`)."""
+
+    editor: str = ""
+    """Editor of the book/paper."""
+
+    publisher: str = ""
+    """Name of the publisher."""
+
+    journal: str = ""
+    """Name of the journal or magazine the article was published in."""
+
+    volume: str | int = ""
+    """Volume number."""
+
+    pages: str = ""
+    """Page range where the article is."""
+
+    number: str = ""
+    """Number of the report or the issue number for a journal article."""
+
+    doi: str = ""
+    """DOI number (like ``10.1038/d41586-018-07848-2``)."""
+
+    issn: list[str] = []
+    """List of ISSN numbers like ``1476-4687``"""
+
+    isbn: list[str] = []
+    """List of ISBN numbers like ``9780201896831``"""
+
+    pdf_url: str = ""
+    """URL to the full article, the PDF version"""
+
+    html_url: str = ""
+    """URL to full article, HTML version"""
+
+    def __post_init__(self):
+        super().__post_init__()
+        if self.date_of_publication is None and self.publishedDate is not None:
+            self.date_of_publication = DateTime(self.publishedDate)