Rewrite search integration

This huge commit is a nearly complete rewrite of the Dolphin search
code. It implements most of the improved Dolphin search UI/UX as
designed and discussed in a collaborative effort by Kristen McWilliam,
Jin Liu, Andy Betts, Tagwerk, a few others and me.
See https://invent.kde.org/system/dolphin/-/issues/46.

# Notable changes

- A toggle to change the search tool is provided as most contributors
deemed that useful in
https://invent.kde.org/system/dolphin/-/merge_requests/642#note_985112.
- The default search is changed to filenamesearch for maximum
reliability.
- Removing all search parameters will take users back to the view state
prior to starting a search instead of keeping the search results open.
- The UI for choosing file types or modification dates has been made
more powerful with more granularity and more options.
- Most search parameters can be configured from a popup menu which
gives us extra space for extra clarity.
- Labels and help buttons as well as hyperlinks to settings makes sure
the user always knows why some search parameters are unavailable in
some contexts.
- Chips show important search parameters while the popup is closed.
They allow quickly removing filters.
- The titles of the search and the input field placeholder message
change to make clear whether file names or file contents are searched.
- When the user actively switches the search tool, whether content
should be searched, or whether to search everywhere, this is preserved
for the initial state of the search bar when the user opens it the next
time after restarting Dolphin.

# Architecture

- The new DolphinQuery class is independent of the UI and contains all
search parameters modifiable in Dolphin as easy setters and getters.
- DolphinQuery objects are also used to update the states of every
component in the search UI. There is now a clear separation of UI and
search configuration/DolphinQuery.
- DolphinQuery is responsible for exporting to and importing from
search URLs.
- The search UI always reflects the currently configured DolphinQuery
no matter if the user changed the UI to change the DolphinQuery or
loaded a DolphinQuery/older search URL which then is reflected in the
UI.
- I tried to simplify all classes and their interaction between each
other as much as possible.
- I added some tests

BUG: 386754
CCBUG: 435119
CCBUG: 458761
BUG: 446387
BUG: 470136
CCBUG: 471556
CCBUG: 475439
CCBUG: 477969
BUG: 480001
BUG: 483578
BUG: 488047
BUG: 488845
BUG: 500103
FIXED-IN: 25.08

1 files changed, 99 insertions, 0 deletions

diff --git a/src/search/popup.h b/src/search/popup.h
new file mode 100644
index 000000000..423c9dde6
--- /dev/null
+++ b/src/search/popup.h
@@ -0,0 +1,99 @@
+/*
+    This file is part of the KDE project
+    SPDX-FileCopyrightText: 2024 Felix Ernst <[email protected]>
+
+    SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
+*/
+
+#ifndef POPUP_H
+#define POPUP_H
+
+#include "dolphinquery.h"
+#include "updatablestateinterface.h"
+#include "widgetmenu.h"
+
+#include <KMessageWidget>
+
+#include <QUrl>
+
+class KContextualHelpButton;
+class QRadioButton;
+class QToolButton;
+
+namespace Search
+{
+class DateSelector;
+class FileTypeSelector;
+class MinimumRatingSelector;
+class TagsSelector;
+
+/** @returns the localized name for the Filenamesearch search tool for use in user interfaces. */
+QString filenamesearchUiName();
+
+/** @returns the localized name for the Baloo search tool for use in user interfaces. */
+QString balooUiName();
+
+/**
+ * This object contains most of the UI to set the search configuration.
+ */
+class Popup : public WidgetMenu, public UpdatableStateInterface
+{
+    Q_OBJECT
+
+public:
+    explicit Popup(std::shared_ptr<const DolphinQuery> dolphinQuery, QWidget *parent = nullptr);
+
+Q_SIGNALS:
+    /** Is emitted whenever settings have changed and a new search might be necessary. */
+    void configurationChanged(const DolphinQuery &dolphinQuery);
+
+    /**
+     * Requests for @p message with the given @p messageType to be shown to the user in a non-modal way.
+     */
+    void showMessage(const QString &message, KMessageWidget::MessageType messageType);
+
+    /**
+     * Requests for a progress update to be shown to the user in a non-modal way.
+     * @param currentlyRunningTaskTitle     The task that is currently progressing.
+     * @param installationProgressPercent   The current percentage of completion.
+     */
+    void showInstallationProgress(const QString &currentlyRunningTaskTitle, int installationProgressPercent);
+
+private:
+    QWidget *init() override;
+
+    void updateState(const std::shared_ptr<const DolphinQuery> &dolphinQuery) override;
+
+private Q_SLOTS:
+    /**
+     * Opens KFind if KFind is installed.
+     * If KFind is not installed, this method asynchronously starts a Filelight installation using DolphinPackageInstaller. @see DolphinPackageInstaller.
+     * Installation success or failure is reported through showMessage(). @see Popup::showMessage().
+     * Installation progress is reported through showInstallationProgress(). @see Popup::showInstallationProgress().
+     */
+    void slotKFindButtonClicked();
+
+private:
+    QRadioButton *m_searchInFileNamesRadioButton = nullptr;
+    QRadioButton *m_searchInFileContentsRadioButton = nullptr;
+    QRadioButton *m_filenamesearchRadioButton = nullptr;
+    KContextualHelpButton *m_filenamesearchContextualHelpButton = nullptr;
+    QRadioButton *m_balooRadioButton = nullptr;
+    KContextualHelpButton *m_balooContextualHelpButton = nullptr;
+    /** A container widget for easy showing/hiding of all selectors. */
+    QWidget *m_selectorsLayoutWidget = nullptr;
+    /** Allows to set the file type each search result is expected to have. */
+    FileTypeSelector *m_typeSelector = nullptr;
+    /** Allows to set a date since when each search result needs to have been modified. */
+    DateSelector *m_dateSelector = nullptr;
+    /** Allows selecting the minimum rating search results are expected to have. */
+    MinimumRatingSelector *m_ratingSelector = nullptr;
+    /** Allows to set tags which each search result is required to have. */
+    TagsSelector *m_tagsSelector = nullptr;
+    /** A button that allows installing or opening KFind. */
+    QToolButton *m_kFindButton = nullptr;
+};
+
+}
+
+#endif // POPUP_H