Add entry editing functionality with auto-save; enhance input validation and navigation

src/hosts/main.py

@@ -6,10 +6,12 @@ This module contains the main application class and entry point function.
 
 from textual.app import App, ComposeResult
 from textual.containers import Horizontal, Vertical
-from textual.widgets import Header, Footer, Static, DataTable
+from textual.widgets import Header, Footer, Static, DataTable, Input, Checkbox, Label
 from textual.binding import Binding
 from textual.reactive import reactive
 from rich.text import Text
+import ipaddress
+import re
 
 from .core.parser import HostsParser
 from .core.models import HostsFile
@@ -89,6 +91,29 @@ class HostsManagerApp(App):
     }
     
     /* DataTable row styling - colors are now handled via Rich Text objects */
+    
+    .hidden {
+        display: none;
+    }
+    
+    #entry-edit-form {
+        height: auto;
+        padding: 1;
+    }
+    
+    #entry-edit-form Label {
+        margin-bottom: 1;
+        color: $accent;
+        text-style: bold;
+    }
+    
+    #entry-edit-form Input {
+        margin-bottom: 1;
+    }
+    
+    #entry-edit-form Checkbox {
+        margin-bottom: 1;
+    }
     """
     
     BINDINGS = [
@@ -99,10 +124,14 @@ class HostsManagerApp(App):
         Binding("n", "sort_by_hostname", "Sort by Hostname"),
         Binding("c", "config", "Config"),
         Binding("ctrl+e", "toggle_edit_mode", "Edit Mode"),
+        Binding("e", "edit_entry", "Edit Entry", show=False),
         Binding("space", "toggle_entry", "Toggle Entry", show=False),
         Binding("ctrl+s", "save_file", "Save", show=False),
         Binding("shift+up", "move_entry_up", "Move Up", show=False),
         Binding("shift+down", "move_entry_down", "Move Down", show=False),
+        Binding("escape", "exit_edit_entry", "Exit Edit", show=False),
+        Binding("tab", "next_field", "Next Field", show=False),
+        Binding("shift+tab", "prev_field", "Prev Field", show=False),
         ("ctrl+c", "quit", "Quit"),
     ]
     
@@ -110,6 +139,7 @@ class HostsManagerApp(App):
     hosts_file: reactive[HostsFile] = reactive(HostsFile())
     selected_entry_index: reactive[int] = reactive(0)
     edit_mode: reactive[bool] = reactive(False)
+    entry_edit_mode: reactive[bool] = reactive(False)
     sort_column: reactive[str] = reactive("")  # "ip" or "hostname"
     sort_ascending: reactive[bool] = reactive(True)
     
@@ -137,6 +167,15 @@ class HostsManagerApp(App):
                 right_pane.border_title = "Entry Details"
                 with right_pane:
                     yield Static("", id="entry-details")
+                    with Vertical(id="entry-edit-form", classes="hidden"):
+                        yield Label("IP Address:")
+                        yield Input(id="ip-input", placeholder="Enter IP address")
+                        yield Label("Hostname:")
+                        yield Input(id="hostname-input", placeholder="Enter hostname")
+                        yield Label("Comment:")
+                        yield Input(id="comment-input", placeholder="Enter comment (optional)")
+                        yield Label("Active:")
+                        yield Checkbox(id="active-checkbox", value=True)
                 yield right_pane
             
             yield Static("", classes="status-bar", id="status")
@@ -322,7 +361,19 @@ class HostsManagerApp(App):
     
     def update_entry_details(self) -> None:
         """Update the right pane with selected entry details."""
+        if self.entry_edit_mode:
+            self.update_edit_form()
+        else:
+            self.update_details_display()
+    
+    def update_details_display(self) -> None:
+        """Update the static details display."""
         details_widget = self.query_one("#entry-details", Static)
+        edit_form = self.query_one("#entry-edit-form")
+        
+        # Show details, hide edit form
+        details_widget.remove_class("hidden")
+        edit_form.add_class("hidden")
         
         if not self.hosts_file.entries:
             details_widget.update("No entries loaded")
@@ -374,6 +425,31 @@ class HostsManagerApp(App):
         
         details_widget.update("\n".join(details_lines))
     
+    def update_edit_form(self) -> None:
+        """Update the edit form with current entry values."""
+        details_widget = self.query_one("#entry-details", Static)
+        edit_form = self.query_one("#entry-edit-form")
+        
+        # Hide details, show edit form
+        details_widget.add_class("hidden")
+        edit_form.remove_class("hidden")
+        
+        if not self.hosts_file.entries or self.selected_entry_index >= len(self.hosts_file.entries):
+            return
+        
+        entry = self.hosts_file.entries[self.selected_entry_index]
+        
+        # Update form fields with current entry values
+        ip_input = self.query_one("#ip-input", Input)
+        hostname_input = self.query_one("#hostname-input", Input)
+        comment_input = self.query_one("#comment-input", Input)
+        active_checkbox = self.query_one("#active-checkbox", Checkbox)
+        
+        ip_input.value = entry.ip_address
+        hostname_input.value = ', '.join(entry.hostnames)
+        comment_input.value = entry.comment or ""
+        active_checkbox.value = entry.is_active
+    
     def update_status(self, message: str = "") -> None:
         """Update the status bar."""
         status_widget = self.query_one("#status", Static)
@@ -437,7 +513,7 @@ class HostsManagerApp(App):
     def action_help(self) -> None:
         """Show help information."""
         # For now, just update the status with help info
-        self.update_status("Help: ↑/↓ Navigate, r Reload, q Quit, h Help, c Config")
+        self.update_status("Help: ↑/↓ Navigate, r Reload, q Quit, h Help, c Config, e Edit")
     
     def action_config(self) -> None:
         """Show configuration modal."""
@@ -449,7 +525,6 @@ class HostsManagerApp(App):
         
         self.push_screen(ConfigModal(self.config), handle_config_result)
     
-    
     def action_sort_by_ip(self) -> None:
         """Sort entries by IP address, toggle ascending/descending."""
         # Toggle sort direction if already sorting by IP
@@ -512,6 +587,168 @@ class HostsManagerApp(App):
             else:
                 self.update_status(f"Error entering edit mode: {message}")
     
+    def action_edit_entry(self) -> None:
+        """Enter edit mode for the selected entry."""
+        if not self.edit_mode:
+            self.update_status("❌ Cannot edit entry: Application is in read-only mode. Press 'Ctrl+E' to enable edit mode.")
+            return
+        
+        if not self.hosts_file.entries:
+            self.update_status("No entries to edit")
+            return
+        
+        if self.selected_entry_index >= len(self.hosts_file.entries):
+            self.update_status("Invalid entry selected")
+            return
+        
+        entry = self.hosts_file.entries[self.selected_entry_index]
+        if entry.is_default_entry():
+            self.update_status("❌ Cannot edit system default entry")
+            return
+        
+        self.entry_edit_mode = True
+        self.update_entry_details()
+        
+        # Focus on the IP address input field
+        ip_input = self.query_one("#ip-input", Input)
+        ip_input.focus()
+        
+        self.update_status("Editing entry - Use Tab/Shift+Tab to navigate, ESC to exit")
+    
+    def action_exit_edit_entry(self) -> None:
+        """Exit entry edit mode and return focus to the entries table."""
+        if self.entry_edit_mode:
+            self.entry_edit_mode = False
+            self.update_entry_details()
+            
+            # Return focus to the entries table
+            table = self.query_one("#entries-table", DataTable)
+            table.focus()
+            
+            self.update_status("Exited entry edit mode")
+    
+    def action_next_field(self) -> None:
+        """Move to the next field in edit mode."""
+        if not self.entry_edit_mode:
+            return
+        
+        # Get all input fields in order
+        fields = [
+            self.query_one("#ip-input", Input),
+            self.query_one("#hostname-input", Input),
+            self.query_one("#comment-input", Input),
+            self.query_one("#active-checkbox", Checkbox)
+        ]
+        
+        # Find currently focused field and move to next
+        for i, field in enumerate(fields):
+            if field.has_focus:
+                next_field = fields[(i + 1) % len(fields)]
+                next_field.focus()
+                break
+    
+    def action_prev_field(self) -> None:
+        """Move to the previous field in edit mode."""
+        if not self.entry_edit_mode:
+            return
+        
+        # Get all input fields in order
+        fields = [
+            self.query_one("#ip-input", Input),
+            self.query_one("#hostname-input", Input),
+            self.query_one("#comment-input", Input),
+            self.query_one("#active-checkbox", Checkbox)
+        ]
+        
+        # Find currently focused field and move to previous
+        for i, field in enumerate(fields):
+            if field.has_focus:
+                prev_field = fields[(i - 1) % len(fields)]
+                prev_field.focus()
+                break
+    
+    def on_key(self, event) -> None:
+        """Handle key events to override default tab behavior in edit mode."""
+        if self.entry_edit_mode and event.key == "tab":
+            # Prevent default tab behavior and use our custom navigation
+            event.prevent_default()
+            self.action_next_field()
+        elif self.entry_edit_mode and event.key == "shift+tab":
+            # Prevent default shift+tab behavior and use our custom navigation
+            event.prevent_default() 
+            self.action_prev_field()
+    
+    def on_input_changed(self, event: Input.Changed) -> None:
+        """Handle input field changes and auto-save."""
+        if not self.entry_edit_mode or not self.edit_mode:
+            return
+        
+        if event.input.id in ["ip-input", "hostname-input", "comment-input"]:
+            self.save_entry_changes()
+    
+    def on_checkbox_changed(self, event: Checkbox.Changed) -> None:
+        """Handle checkbox changes and auto-save."""
+        if not self.entry_edit_mode or not self.edit_mode:
+            return
+        
+        if event.checkbox.id == "active-checkbox":
+            self.save_entry_changes()
+    
+    def save_entry_changes(self) -> None:
+        """Save the current entry changes."""
+        if not self.hosts_file.entries or self.selected_entry_index >= len(self.hosts_file.entries):
+            return
+        
+        entry = self.hosts_file.entries[self.selected_entry_index]
+        
+        # Get values from form fields
+        ip_input = self.query_one("#ip-input", Input)
+        hostname_input = self.query_one("#hostname-input", Input)
+        comment_input = self.query_one("#comment-input", Input)
+        active_checkbox = self.query_one("#active-checkbox", Checkbox)
+        
+        # Validate IP address
+        try:
+            ipaddress.ip_address(ip_input.value.strip())
+        except ValueError:
+            self.update_status("❌ Invalid IP address")
+            return
+        
+        # Validate hostname(s)
+        hostnames = [h.strip() for h in hostname_input.value.split(',') if h.strip()]
+        if not hostnames:
+            self.update_status("❌ At least one hostname is required")
+            return
+        
+        hostname_pattern = re.compile(
+            r'^[a-zA-Z0-9]([a-zA-Z0-9\-]{0,61}[a-zA-Z0-9])?(\.[a-zA-Z0-9]([a-zA-Z0-9\-]{0,61}[a-zA-Z0-9])?)*$'
+        )
+        
+        for hostname in hostnames:
+            if not hostname_pattern.match(hostname):
+                self.update_status(f"❌ Invalid hostname: {hostname}")
+                return
+        
+        # Update the entry
+        entry.ip_address = ip_input.value.strip()
+        entry.hostnames = hostnames
+        entry.comment = comment_input.value.strip() or None
+        entry.is_active = active_checkbox.value
+        
+        # Save to file
+        success, message = self.manager.save_hosts_file(self.hosts_file)
+        if success:
+            # Update the table display
+            self.populate_entries_table()
+            # Restore cursor position
+            table = self.query_one("#entries-table", DataTable)
+            display_index = self.actual_index_to_display_index(self.selected_entry_index)
+            if table.row_count > 0 and display_index < table.row_count:
+                table.move_cursor(row=display_index)
+            self.update_status("Entry saved successfully")
+        else:
+            self.update_status(f"❌ Error saving entry: {message}")
+    
     def action_toggle_entry(self) -> None:
         """Toggle the active state of the selected entry."""
         if not self.edit_mode:
@@ -616,6 +853,10 @@ class HostsManagerApp(App):
     
     def action_quit(self) -> None:
         """Quit the application."""
+        # If in entry edit mode, exit it first
+        if self.entry_edit_mode:
+            self.action_exit_edit_entry()
+        
         # If in edit mode, exit it first
         if self.edit_mode:
             self.manager.exit_edit_mode()