Fix #6: Make advanced filtering reachable from the TUI

README.md

@@ -13,6 +13,8 @@ on macOS and Linux.
 ## What it does
 
 - Browses, searches, and sorts active and inactive Host Entries.
+- Filters Host Entries by status, entry type, DNS resolution state, and search
+  fields.
 - Hides or shows protected localhost and broadcasthost Default Entries.
 - Adds, edits, deletes, activates, deactivates, and reorders Host Entries.
 - Creates DNS Entries and manually refreshes their resolved IP addresses.
@@ -65,6 +67,7 @@ including persistence behavior and manual recovery.
 | `d` | Delete the selected Host Entry |
 | `Space` | Activate or deactivate the selected Host Entry |
 | `Ctrl+S` | Save the current in-memory state |
+| `Ctrl+F` | Open advanced filters |
 | `?` | Show help |
 | `q` or `Ctrl+C` | Quit |
 

docs/user-guide.md

@@ -29,6 +29,8 @@ The application opens in Read-only Mode. In this mode you can:
 - select a Host Entry and inspect all of its hostnames, comment, state, and DNS
   details;
 - search by hostname, IP address, or comment;
+- use `Ctrl+F` to combine status, entry-type, DNS-resolution, and search
+  filters;
 - sort by IP address or Canonical Hostname;
 - show or hide Default Entries from the configuration screen; and
 - reload `/etc/hosts` from disk.
@@ -221,6 +223,7 @@ continually retrying it.
 | `i` | Sort by IP address |
 | `h` | Sort by Canonical Hostname |
 | `Ctrl+R` | Reload `/etc/hosts` |
+| `Ctrl+F` | Open advanced filters |
 | `c` | Open configuration |
 | `?` | Show help |
 | `q` or `Ctrl+C` | Quit |

src/hosts/tui/app.py

@@ -30,6 +30,7 @@ from ..core.filters import EntryFilter, FilterOptions
 from .config_modal import ConfigModal
 from .add_entry_modal import AddEntryModal
 from .delete_confirmation_modal import DeleteConfirmationModal
+from .filter_modal import FilterModal
 from .custom_footer import CustomFooter
 from .styles import HOSTS_MANAGER_CSS
 from .keybindings import HOSTS_MANAGER_BINDINGS
@@ -514,6 +515,41 @@ class HostsManagerApp(App):
 
         self.push_screen(ConfigModal(self.config), handle_config_result)
 
+    def action_show_filters(self) -> None:
+        """Open the advanced filter controls and apply their returned options."""
+
+        def handle_filter_result(filter_options: FilterOptions | None) -> None:
+            if filter_options is None:
+                self.update_status("Filtering cancelled")
+                return
+
+            self.current_filter_options = filter_options
+            self.search_term = filter_options.search_term or ""
+
+            try:
+                self.query_one("#search-input", Input).value = self.search_term
+            except Exception:
+                pass
+
+            self.table_handler.populate_entries_table()
+            self.details_handler.update_entry_details()
+
+            counts = self.entry_filter.count_filtered_entries(
+                self.hosts_file.entries, filter_options
+            )
+            self.update_status(
+                f"Filter applied: showing {counts['filtered']} of {counts['total']} entries"
+            )
+
+        self.push_screen(
+            FilterModal(
+                initial_options=self.current_filter_options,
+                entries=self.hosts_file.entries,
+                entry_filter=self.entry_filter,
+            ),
+            handle_filter_result,
+        )
+
     def action_sort_by_ip(self) -> None:
         """Sort entries by IP address, toggle ascending/descending."""
         self.table_handler.sort_entries_by_ip()

src/hosts/tui/filter_modal.py

@@ -0,0 +1,594 @@
+"""
+Filter modal for advanced entry filtering configuration.
+
+This module provides a professional modal dialog for configuring comprehensive
+filtering options including status, type, resolution status, and search filtering.
+"""
+
+from textual.app import ComposeResult
+from textual.containers import Grid, Horizontal, Container
+from textual.widgets import (
+    Static,
+    Button,
+    Checkbox,
+    Input,
+    Select,
+    Label,
+    RadioSet,
+    RadioButton,
+    Collapsible,
+)
+from textual.screen import ModalScreen
+from textual.reactive import reactive
+from textual import on
+from typing import Optional, Dict, List
+
+from ..core.filters import FilterOptions, EntryFilter
+
+
+class FilterModal(ModalScreen[Optional[FilterOptions]]):
+    """Advanced filtering configuration modal."""
+
+    DEFAULT_CSS = """
+    FilterModal {
+        align: center middle;
+    }
+
+    #filter-dialog {
+        grid-size: 1;
+        grid-gutter: 1 2;
+        grid-rows: auto 1fr auto;
+        padding: 0 1;
+        width: 80;
+        height: auto;
+        border: thick $background 80%;
+        background: $surface;
+        max-height: 90%;
+    }
+
+    #filter-header {
+        dock: top;
+        width: 1fr;
+        height: 3;
+        content-align: center middle;
+        text-style: bold;
+        background: $primary;
+        color: $text;
+    }
+
+    #filter-content {
+        layout: vertical;
+        overflow-y: auto;
+        height: auto;
+        max-height: 70vh;
+        padding: 1;
+    }
+
+    #filter-actions {
+        dock: bottom;
+        layout: horizontal;
+        width: 1fr;
+        height: 3;
+        align: center middle;
+        padding: 0 1;
+        background: $panel;
+    }
+
+    .filter-section {
+        margin: 1 0;
+        padding: 1;
+        border: round $primary 20%;
+        background: $panel;
+    }
+
+    .filter-section-title {
+        text-style: bold;
+        color: $primary;
+        margin-bottom: 1;
+    }
+
+    .filter-checkboxes {
+        layout: vertical;
+        margin: 0 2;
+    }
+
+    .filter-radios {
+        layout: vertical;
+        margin: 0 2;
+    }
+
+    .filter-input-row {
+        layout: horizontal;
+        margin: 0 2;
+        height: 3;
+        align: left middle;
+    }
+
+    .filter-input-label {
+        width: 20;
+        content-align: left middle;
+        margin-right: 1;
+    }
+
+    .filter-input {
+        width: 30;
+    }
+
+    .preset-row {
+        layout: horizontal;
+        margin: 1 2;
+        height: 3;
+        align: left middle;
+    }
+
+    .preset-select {
+        width: 30;
+        margin-right: 2;
+    }
+
+    Button {
+        margin: 0 1;
+        min-width: 12;
+    }
+
+    Checkbox {
+        margin: 0 1;
+    }
+
+    RadioButton {
+        margin: 0 1;
+    }
+
+    .count-display {
+        text-style: italic;
+        color: $text-muted;
+        content-align: center middle;
+        height: 1;
+        margin: 1 0;
+    }
+    """
+
+    # Reactive properties for real-time updates
+    current_options: reactive[FilterOptions] = reactive(FilterOptions())
+    entry_counts: reactive[Dict[str, int]] = reactive({})
+
+    def __init__(
+        self,
+        initial_options: Optional[FilterOptions] = None,
+        entries: Optional[List] = None,
+        entry_filter: Optional[EntryFilter] = None,
+    ):
+        """
+        Initialize filter modal.
+
+        Args:
+            initial_options: Current filter options to display
+            entries: List of entries for count preview
+            entry_filter: EntryFilter instance for applying filters
+        """
+        super().__init__()
+        self.current_options = initial_options or FilterOptions()
+        self.entries = entries or []
+        self.entry_filter = entry_filter or EntryFilter()
+        self.entry_counts = self._calculate_counts()
+
+    def compose(self) -> ComposeResult:
+        """Compose the filter modal interface."""
+        with Grid(id="filter-dialog"):
+            yield Static("Advanced Filtering", id="filter-header")
+
+            with Container(id="filter-content"):
+                # Filter presets section
+                with Collapsible(title="Filter Presets", collapsed=False):
+                    with Container(classes="filter-section"):
+                        with Horizontal(classes="preset-row"):
+                            yield Label("Preset:", classes="filter-input-label")
+                            yield Select(
+                                [
+                                    (name, name)
+                                    for name in self.entry_filter.get_preset_names()
+                                ],
+                                value=self.current_options.preset_name or Select.BLANK,
+                                id="preset-select",
+                                classes="preset-select",
+                            )
+                            yield Button("Load", id="load-preset", variant="primary")
+                            yield Button("Save", id="save-preset")
+                            yield Button("Delete", id="delete-preset", variant="error")
+
+                # Status filtering section
+                with Collapsible(title="Status Filtering", collapsed=False):
+                    with Container(classes="filter-section"):
+                        yield Static("Status Filtering", classes="filter-section-title")
+                        with RadioSet(id="status-filter-type"):
+                            yield RadioButton("Show All", id="status-all")
+                            yield RadioButton("Active Only", id="status-active")
+                            yield RadioButton("Inactive Only", id="status-inactive")
+                            yield RadioButton("Custom", id="status-custom")
+
+                        with Container(
+                            classes="filter-checkboxes", id="status-custom-options"
+                        ):
+                            yield Checkbox(
+                                "Show Active Entries", value=True, id="show-active"
+                            )
+                            yield Checkbox(
+                                "Show Inactive Entries", value=True, id="show-inactive"
+                            )
+
+                # DNS type filtering section
+                with Collapsible(title="Entry Type Filtering", collapsed=False):
+                    with Container(classes="filter-section"):
+                        yield Static(
+                            "Entry Type Filtering", classes="filter-section-title"
+                        )
+                        with RadioSet(id="type-filter-type"):
+                            yield RadioButton("Show All", id="type-all")
+                            yield RadioButton("DNS Entries Only", id="type-dns")
+                            yield RadioButton("IP Entries Only", id="type-ip")
+                            yield RadioButton("Custom", id="type-custom")
+
+                        with Container(
+                            classes="filter-checkboxes", id="type-custom-options"
+                        ):
+                            yield Checkbox(
+                                "Show DNS Entries", value=True, id="show-dns"
+                            )
+                            yield Checkbox("Show IP Entries", value=True, id="show-ip")
+
+                # DNS resolution status filtering section
+                with Collapsible(title="Resolution Status Filtering", collapsed=False):
+                    with Container(classes="filter-section"):
+                        yield Static(
+                            "Resolution Status Filtering",
+                            classes="filter-section-title",
+                        )
+                        with RadioSet(id="resolution-filter-type"):
+                            yield RadioButton("Show All", id="resolution-all")
+                            yield RadioButton(
+                                "Resolved Only",
+                                id="resolution-resolved",
+                            )
+                            yield RadioButton(
+                                "Mismatches Only",
+                                id="resolution-mismatch",
+                            )
+                            yield RadioButton("Custom", id="resolution-custom")
+
+                        with Container(
+                            classes="filter-checkboxes", id="resolution-custom-options"
+                        ):
+                            yield Checkbox(
+                                "Show Resolved", value=True, id="show-resolved"
+                            )
+                            yield Checkbox(
+                                "Show Unresolved", value=True, id="show-unresolved"
+                            )
+                            yield Checkbox(
+                                "Show Resolving", value=True, id="show-resolving"
+                            )
+                            yield Checkbox("Show Failed", value=True, id="show-failed")
+                            yield Checkbox(
+                                "Show Mismatched", value=True, id="show-mismatched"
+                            )
+
+                # Search filtering section
+                with Collapsible(title="Search Filtering", collapsed=True):
+                    with Container(classes="filter-section"):
+                        yield Static("Search Filtering", classes="filter-section-title")
+
+                        with Horizontal(classes="filter-input-row"):
+                            yield Label("Search term:", classes="filter-input-label")
+                            yield Input(
+                                placeholder="Enter search term...",
+                                value=self.current_options.search_term or "",
+                                id="search-term",
+                                classes="filter-input",
+                            )
+
+                        with Container(classes="filter-checkboxes"):
+                            yield Checkbox(
+                                "Search in hostnames", value=True, id="search-hostnames"
+                            )
+                            yield Checkbox(
+                                "Search in comments", value=True, id="search-comments"
+                            )
+                            yield Checkbox(
+                                "Search in IP addresses", value=True, id="search-ips"
+                            )
+                            yield Checkbox(
+                                "Case sensitive",
+                                value=False,
+                                id="search-case-sensitive",
+                            )
+
+                # Entry count display
+                yield Static("", id="count-display", classes="count-display")
+
+            with Horizontal(id="filter-actions"):
+                yield Button("Apply", id="apply", variant="primary")
+                yield Button("Reset", id="reset")
+                yield Button("Cancel", id="cancel")
+
+    def on_mount(self) -> None:
+        """Initialize the modal with current options."""
+        self._update_ui_from_options()
+        self._update_count_display()
+
+    def _update_ui_from_options(self) -> None:
+        """Update UI controls to reflect current options."""
+        options = self.current_options
+
+        # Status filtering
+        if options.active_only:
+            self.query_one("#status-active", RadioButton).value = True
+        elif options.inactive_only:
+            self.query_one("#status-inactive", RadioButton).value = True
+        elif options.show_active and options.show_inactive:
+            self.query_one("#status-all", RadioButton).value = True
+        else:
+            self.query_one("#status-custom", RadioButton).value = True
+
+        self.query_one("#show-active", Checkbox).value = options.show_active
+        self.query_one("#show-inactive", Checkbox).value = options.show_inactive
+
+        # Type filtering
+        if options.dns_only:
+            self.query_one("#type-dns", RadioButton).value = True
+        elif options.ip_only:
+            self.query_one("#type-ip", RadioButton).value = True
+        elif options.show_dns_entries and options.show_ip_entries:
+            self.query_one("#type-all", RadioButton).value = True
+        else:
+            self.query_one("#type-custom", RadioButton).value = True
+
+        self.query_one("#show-dns", Checkbox).value = options.show_dns_entries
+        self.query_one("#show-ip", Checkbox).value = options.show_ip_entries
+
+        # Resolution status filtering
+        if options.resolved_only:
+            self.query_one("#resolution-resolved", RadioButton).value = True
+        elif options.mismatch_only:
+            self.query_one("#resolution-mismatch", RadioButton).value = True
+        elif (
+            options.show_resolved
+            and options.show_unresolved
+            and options.show_resolving
+            and options.show_failed
+            and options.show_mismatched
+        ):
+            self.query_one("#resolution-all", RadioButton).value = True
+        else:
+            self.query_one("#resolution-custom", RadioButton).value = True
+
+        self.query_one("#show-resolved", Checkbox).value = options.show_resolved
+        self.query_one("#show-unresolved", Checkbox).value = options.show_unresolved
+        self.query_one("#show-resolving", Checkbox).value = options.show_resolving
+        self.query_one("#show-failed", Checkbox).value = options.show_failed
+        self.query_one("#show-mismatched", Checkbox).value = options.show_mismatched
+
+        # Search filtering
+        if options.search_term:
+            self.query_one("#search-term", Input).value = options.search_term
+        self.query_one(
+            "#search-hostnames", Checkbox
+        ).value = options.search_in_hostnames
+        self.query_one("#search-comments", Checkbox).value = options.search_in_comments
+        self.query_one("#search-ips", Checkbox).value = options.search_in_ips
+        self.query_one(
+            "#search-case-sensitive", Checkbox
+        ).value = options.case_sensitive
+
+        self._update_custom_options_visibility()
+
+    def _update_custom_options_visibility(self) -> None:
+        """Show/hide custom option containers based on radio selections."""
+        # Status custom options
+        status_custom = self.query_one("#status-custom", RadioButton).value
+        status_container = self.query_one("#status-custom-options")
+        status_container.display = status_custom
+
+        # Type custom options
+        type_custom = self.query_one("#type-custom", RadioButton).value
+        type_container = self.query_one("#type-custom-options")
+        type_container.display = type_custom
+
+        # Resolution custom options
+        resolution_custom = self.query_one("#resolution-custom", RadioButton).value
+        resolution_container = self.query_one("#resolution-custom-options")
+        resolution_container.display = resolution_custom
+
+    def _calculate_counts(self) -> Dict[str, int]:
+        """Calculate entry counts for current filter options."""
+        if not self.entries:
+            return {}
+        return self.entry_filter.count_filtered_entries(
+            self.entries, self.current_options
+        )
+
+    def _update_count_display(self) -> None:
+        """Update the count display with current filter results."""
+        counts = self._calculate_counts()
+        if counts:
+            count_text = (
+                f"Showing {counts['filtered']} of {counts['total']} entries "
+                f"({counts['active']} active, {counts['inactive']} inactive)"
+            )
+        else:
+            count_text = "No entries to filter"
+
+        self.query_one("#count-display", Static).update(count_text)
+
+    def _get_current_options_from_ui(self) -> FilterOptions:
+        """Extract current filter options from UI controls."""
+        # Status filtering
+        status_type = self.query_one("#status-filter-type", RadioSet).pressed_button
+        if status_type and status_type.id == "status-active":
+            show_active, show_inactive = True, False
+            active_only, inactive_only = True, False
+        elif status_type and status_type.id == "status-inactive":
+            show_active, show_inactive = False, True
+            active_only, inactive_only = False, True
+        elif status_type and status_type.id == "status-all":
+            show_active, show_inactive = True, True
+            active_only, inactive_only = False, False
+        else:  # custom
+            show_active = self.query_one("#show-active", Checkbox).value
+            show_inactive = self.query_one("#show-inactive", Checkbox).value
+            active_only, inactive_only = False, False
+
+        # Type filtering
+        type_type = self.query_one("#type-filter-type", RadioSet).pressed_button
+        if type_type and type_type.id == "type-dns":
+            show_dns_entries, show_ip_entries = True, False
+            dns_only, ip_only = True, False
+        elif type_type and type_type.id == "type-ip":
+            show_dns_entries, show_ip_entries = False, True
+            dns_only, ip_only = False, True
+        elif type_type and type_type.id == "type-all":
+            show_dns_entries, show_ip_entries = True, True
+            dns_only, ip_only = False, False
+        else:  # custom
+            show_dns_entries = self.query_one("#show-dns", Checkbox).value
+            show_ip_entries = self.query_one("#show-ip", Checkbox).value
+            dns_only, ip_only = False, False
+
+        # Resolution status filtering
+        resolution_type = self.query_one(
+            "#resolution-filter-type", RadioSet
+        ).pressed_button
+        if resolution_type and resolution_type.id == "resolution-resolved":
+            resolved_only, mismatch_only = True, False
+            (
+                show_resolved,
+                show_unresolved,
+                show_resolving,
+                show_failed,
+                show_mismatched,
+            ) = True, False, False, False, False
+        elif resolution_type and resolution_type.id == "resolution-mismatch":
+            resolved_only, mismatch_only = False, True
+            (
+                show_resolved,
+                show_unresolved,
+                show_resolving,
+                show_failed,
+                show_mismatched,
+            ) = False, False, False, False, True
+        elif resolution_type and resolution_type.id == "resolution-all":
+            resolved_only, mismatch_only = False, False
+            (
+                show_resolved,
+                show_unresolved,
+                show_resolving,
+                show_failed,
+                show_mismatched,
+            ) = True, True, True, True, True
+        else:  # custom
+            resolved_only, mismatch_only = False, False
+            show_resolved = self.query_one("#show-resolved", Checkbox).value
+            show_unresolved = self.query_one("#show-unresolved", Checkbox).value
+            show_resolving = self.query_one("#show-resolving", Checkbox).value
+            show_failed = self.query_one("#show-failed", Checkbox).value
+            show_mismatched = self.query_one("#show-mismatched", Checkbox).value
+
+        # Search filtering
+        search_term = self.query_one("#search-term", Input).value or None
+        search_hostnames = self.query_one("#search-hostnames", Checkbox).value
+        search_comments = self.query_one("#search-comments", Checkbox).value
+        search_ips = self.query_one("#search-ips", Checkbox).value
+        case_sensitive = self.query_one("#search-case-sensitive", Checkbox).value
+
+        return FilterOptions(
+            show_active=show_active,
+            show_inactive=show_inactive,
+            active_only=active_only,
+            inactive_only=inactive_only,
+            show_dns_entries=show_dns_entries,
+            show_ip_entries=show_ip_entries,
+            dns_only=dns_only,
+            ip_only=ip_only,
+            show_resolved=show_resolved,
+            show_unresolved=show_unresolved,
+            show_resolving=show_resolving,
+            show_failed=show_failed,
+            show_mismatched=show_mismatched,
+            mismatch_only=mismatch_only,
+            resolved_only=resolved_only,
+            search_term=search_term,
+            search_in_hostnames=search_hostnames,
+            search_in_comments=search_comments,
+            search_in_ips=search_ips,
+            case_sensitive=case_sensitive,
+        )
+
+    @on(RadioSet.Changed)
+    def on_radio_changed(self, event: RadioSet.Changed) -> None:
+        """Handle radio button changes."""
+        self._update_custom_options_visibility()
+        self.current_options = self._get_current_options_from_ui()
+        self._update_count_display()
+
+    @on(Checkbox.Changed)
+    @on(Input.Changed)
+    def on_input_changed(self) -> None:
+        """Handle input changes for real-time preview."""
+        self.current_options = self._get_current_options_from_ui()
+        self._update_count_display()
+
+    @on(Button.Pressed, "#apply")
+    def on_apply_pressed(self) -> None:
+        """Handle apply button press."""
+        self.dismiss(self._get_current_options_from_ui())
+
+    @on(Button.Pressed, "#cancel")
+    def on_cancel_pressed(self) -> None:
+        """Handle cancel button press."""
+        self.dismiss(None)
+
+    @on(Button.Pressed, "#reset")
+    def on_reset_pressed(self) -> None:
+        """Handle reset button press."""
+        self.current_options = FilterOptions()
+        self._update_ui_from_options()
+        self._update_count_display()
+
+    @on(Button.Pressed, "#load-preset")
+    def on_load_preset_pressed(self) -> None:
+        """Handle load preset button press."""
+        preset_select = self.query_one("#preset-select", Select)
+        if preset_select.value != Select.BLANK:
+            preset_options = self.entry_filter.load_preset(str(preset_select.value))
+            if preset_options:
+                self.current_options = preset_options
+                self._update_ui_from_options()
+                self._update_count_display()
+
+    @on(Button.Pressed, "#save-preset")
+    def on_save_preset_pressed(self) -> None:
+        """Handle save preset button press."""
+        # TODO: Implement preset name input dialog
+        # For now, just save with a generic name
+        current_options = self._get_current_options_from_ui()
+        preset_name = f"Custom Preset {len(self.entry_filter.presets) + 1}"
+        self.entry_filter.save_preset(preset_name, current_options)
+
+        # Update preset select with new preset
+        preset_select = self.query_one("#preset-select", Select)
+        preset_select.set_options(
+            [(name, name) for name in self.entry_filter.get_preset_names()]
+        )
+        preset_select.value = preset_name
+
+    @on(Button.Pressed, "#delete-preset")
+    def on_delete_preset_pressed(self) -> None:
+        """Handle delete preset button press."""
+        preset_select = self.query_one("#preset-select", Select)
+        if preset_select.value != Select.BLANK:
+            preset_name = str(preset_select.value)
+            if self.entry_filter.delete_preset(preset_name):
+                # Update preset select options
+                preset_select.set_options(
+                    [(name, name) for name in self.entry_filter.get_preset_names()]
+                )
+                preset_select.value = Select.BLANK

src/hosts/tui/keybindings.py

@@ -27,6 +27,14 @@ HOSTS_MANAGER_BINDINGS = [
         id="left:toggle_edit_mode",
     ),
     Binding("c", "config", "Configuration", show=True, id="right:config"),
+    Binding(
+        "ctrl+f",
+        "show_filters",
+        "Filter entries",
+        show=True,
+        id="right:filters",
+        priority=True,
+    ),
     Binding(
         "question_mark",
         "help",

tests/test_app.py

@@ -3,9 +3,15 @@
 from contextlib import contextmanager
 from unittest.mock import Mock, patch
 
+import pytest
 from textual.app import SuspendNotSupported
+from textual.widgets import RadioButton, Static
 
+from src.hosts.core.filters import FilterOptions
+from src.hosts.core.models import HostEntry, HostsFile
 from src.hosts.tui.app import HostsManagerApp
+from src.hosts.tui.custom_footer import CustomFooter
+from src.hosts.tui.filter_modal import FilterModal
 
 
 @contextmanager
@@ -14,6 +20,79 @@ def suspended_tui():
     yield
 
 
+def app_with_filterable_entries() -> HostsManagerApp:
+    """Create an app whose filter workflow cannot access the system Hosts File."""
+    app = HostsManagerApp()
+    app.hosts_file = HostsFile(
+        entries=[
+            HostEntry(ip_address="192.0.2.1", hostnames=["active.test"]),
+            HostEntry(
+                ip_address="192.0.2.2",
+                hostnames=["inactive.test"],
+                is_active=False,
+            ),
+        ]
+    )
+    app.load_hosts_file = Mock()
+    return app
+
+
+@pytest.mark.asyncio
+async def test_filter_shortcut_opens_modal_and_applies_the_selected_filter():
+    """The filter shortcut opens a modal whose Apply action changes the view state."""
+    app = app_with_filterable_entries()
+
+    async with app.run_test() as pilot:
+        footer = app.query_one("#custom-footer", CustomFooter)
+        footer_text = footer.query_one("#footer-right", Static).render()
+        assert "ctrl+f Filter entries" in str(footer_text)
+
+        await pilot.press("ctrl+f")
+
+        assert isinstance(app.screen, FilterModal)
+        app.screen.query_one("#status-active", RadioButton).value = True
+        await pilot.pause()
+        await pilot.click("#apply")
+        await pilot.pause()
+
+    assert app.current_filter_options.active_only
+    assert not app.current_filter_options.show_inactive
+    assert [entry.hostnames[0] for entry in app.get_visible_entries()] == [
+        "active.test"
+    ]
+
+
+@pytest.mark.asyncio
+async def test_filter_reset_clears_filters_and_cancel_preserves_applied_filters():
+    """Reset clears the form on Apply, while Cancel leaves the applied filter alone."""
+    app = app_with_filterable_entries()
+    app.current_filter_options = FilterOptions(
+        active_only=True,
+        show_inactive=False,
+    )
+
+    async with app.run_test() as pilot:
+        await pilot.press("ctrl+f")
+        await pilot.click("#reset")
+        await pilot.click("#apply")
+        await pilot.pause()
+
+        assert app.current_filter_options.is_empty()
+
+        await pilot.press("ctrl+f")
+        assert isinstance(app.screen, FilterModal)
+        app.screen.query_one("#status-active", RadioButton).value = True
+        await pilot.pause()
+        await pilot.click("#cancel")
+        await pilot.pause()
+
+    assert app.current_filter_options.is_empty()
+    assert [entry.hostnames[0] for entry in app.get_visible_entries()] == [
+        "active.test",
+        "inactive.test",
+    ]
+
+
 class TestPrivilegedModeAuthorization:
     """Test the user-visible privileged-mode authorization flow."""