script/dom/execcommand/
execcommands.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use script_bindings::inheritance::Castable;
6
7use crate::dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
8use crate::dom::bindings::codegen::Bindings::HTMLElementBinding::HTMLElementMethods;
9use crate::dom::bindings::codegen::Bindings::RangeBinding::RangeMethods;
10use crate::dom::bindings::root::DomRoot;
11use crate::dom::bindings::str::DOMString;
12use crate::dom::document::Document;
13use crate::dom::event::Event;
14use crate::dom::event::inputevent::InputEvent;
15use crate::dom::execcommand::basecommand::CommandName;
16use crate::dom::execcommand::commands::fontsize::legacy_font_size_for;
17use crate::dom::html::htmlelement::HTMLElement;
18use crate::dom::node::Node;
19use crate::dom::selection::Selection;
20use crate::script_runtime::CanGc;
21
22/// <https://w3c.github.io/editing/docs/execCommand/#miscellaneous-commands>
23fn is_command_listed_in_miscellaneous_section(command_name: CommandName) -> bool {
24    matches!(
25        command_name,
26        CommandName::DefaultParagraphSeparator |
27            CommandName::Redo |
28            CommandName::SelectAll |
29            CommandName::StyleWithCss |
30            CommandName::Undo |
31            CommandName::Usecss
32    )
33}
34
35/// <https://w3c.github.io/editing/docs/execCommand/#dfn-map-an-edit-command-to-input-type-value>
36fn mapped_value_of_command(command: CommandName) -> DOMString {
37    match command {
38        CommandName::BackColor => "formatBackColor",
39        CommandName::Bold => "formatBold",
40        CommandName::CreateLink => "insertLink",
41        CommandName::Cut => "deleteByCut",
42        CommandName::Delete => "deleteContentBackward",
43        CommandName::FontName => "formatFontName",
44        CommandName::ForeColor => "formatFontColor",
45        CommandName::ForwardDelete => "deleteContentForward",
46        CommandName::Indent => "formatIndent",
47        CommandName::InsertHorizontalRule => "insertHorizontalRule",
48        CommandName::InsertLineBreak => "insertLineBreak",
49        CommandName::InsertOrderedList => "insertOrderedList",
50        CommandName::InsertParagraph => "insertParagraph",
51        CommandName::InsertText => "insertText",
52        CommandName::InsertUnorderedList => "insertUnorderedList",
53        CommandName::JustifyCenter => "formatJustifyCenter",
54        CommandName::JustifyFull => "formatJustifyFull",
55        CommandName::JustifyLeft => "formatJustifyLeft",
56        CommandName::JustifyRight => "formatJustifyRight",
57        CommandName::Outdent => "formatOutdent",
58        CommandName::Paste => "insertFromPaste",
59        CommandName::Redo => "historyRedo",
60        CommandName::Strikethrough => "formatStrikeThrough",
61        CommandName::Superscript => "formatSuperscript",
62        CommandName::Undo => "historyUndo",
63        _ => "",
64    }
65    .into()
66}
67
68impl Node {
69    fn is_in_plaintext_only_state(&self) -> bool {
70        self.downcast::<HTMLElement>()
71            .is_some_and(|el| el.ContentEditable().str() == "plaintext-only")
72    }
73}
74
75impl Document {
76    /// <https://w3c.github.io/editing/docs/execCommand/#enabled>
77    fn selection_if_command_is_enabled(
78        &self,
79        cx: &mut js::context::JSContext,
80        command_name: CommandName,
81    ) -> Option<DomRoot<Selection>> {
82        let selection = self.GetSelection(CanGc::from_cx(cx))?;
83        // > Among commands defined in this specification, those listed in Miscellaneous commands are always enabled,
84        // > except for the cut command and the paste command.
85        //
86        // Note: cut and paste are listed in the "clipboard commands" section, not the miscellaneous section
87        if is_command_listed_in_miscellaneous_section(command_name) {
88            return Some(selection);
89        }
90        // > The other commands defined here are enabled if the active range is not null,
91        let range = selection.active_range()?;
92        // > its start node is either editable or an editing host,
93        let start_container_editing_host = range.start_container().editing_host_of()?;
94        // > the editing host of its start node is not an EditContext editing host,
95        // TODO
96        // > its end node is either editable or an editing host,
97        let end_container_editing_host = range.end_container().editing_host_of()?;
98        // > the editing host of its end node is not an EditContext editing host,
99        // TODO
100        // > and there is some editing host that is an inclusive ancestor of both its start node and its end node.
101        // TODO
102
103        // Some commands are only enabled if the editing host is *not* in plaintext-only state.
104        if !command_name.is_enabled_in_plaintext_only_state() &&
105            (start_container_editing_host.is_in_plaintext_only_state() ||
106                end_container_editing_host.is_in_plaintext_only_state())
107        {
108            None
109        } else {
110            Some(selection)
111        }
112    }
113
114    /// <https://w3c.github.io/editing/docs/execCommand/#supported>
115    fn command_if_command_is_supported(&self, command_id: &DOMString) -> Option<CommandName> {
116        // https://w3c.github.io/editing/docs/execCommand/#methods-to-query-and-execute-commands
117        // > All of these methods must treat their command argument ASCII case-insensitively.
118        Some(match &*command_id.str().to_lowercase() {
119            "delete" => CommandName::Delete,
120            "defaultparagraphseparator" => CommandName::DefaultParagraphSeparator,
121            "fontsize" => CommandName::FontSize,
122            "stylewithcss" => CommandName::StyleWithCss,
123            _ => return None,
124        })
125    }
126}
127
128pub(crate) trait DocumentExecCommandSupport {
129    fn is_command_supported(&self, command_id: DOMString) -> bool;
130    fn is_command_indeterminate(&self, command_id: DOMString) -> bool;
131    fn command_state_for_command(&self, command_id: DOMString) -> bool;
132    fn command_value_for_command(
133        &self,
134        cx: &mut js::context::JSContext,
135        command_id: DOMString,
136    ) -> DOMString;
137    fn check_support_and_enabled(
138        &self,
139        cx: &mut js::context::JSContext,
140        command_id: &DOMString,
141    ) -> Option<(CommandName, DomRoot<Selection>)>;
142    fn exec_command_for_command_id(
143        &self,
144        cx: &mut js::context::JSContext,
145        command_id: DOMString,
146        value: DOMString,
147    ) -> bool;
148}
149
150impl DocumentExecCommandSupport for Document {
151    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandsupported()>
152    fn is_command_supported(&self, command_id: DOMString) -> bool {
153        self.command_if_command_is_supported(&command_id).is_some()
154    }
155
156    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandindeterm()>
157    fn is_command_indeterminate(&self, command_id: DOMString) -> bool {
158        // Step 1. If command is not supported or has no indeterminacy, return false.
159        // Step 2. Return true if command is indeterminate, otherwise false.
160        self.command_if_command_is_supported(&command_id)
161            .is_some_and(|command| command.is_indeterminate())
162    }
163
164    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandstate()>
165    fn command_state_for_command(&self, command_id: DOMString) -> bool {
166        // Step 1. If command is not supported or has no state, return false.
167        let Some(command) = self.command_if_command_is_supported(&command_id) else {
168            return false;
169        };
170        let Some(state) = command.current_state(self) else {
171            return false;
172        };
173        // Step 2. If the state override for command is set, return it.
174        // Step 3. Return true if command's state is true, otherwise false.
175        self.state_override(&command).unwrap_or(state)
176    }
177
178    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandvalue()>
179    fn command_value_for_command(
180        &self,
181        cx: &mut js::context::JSContext,
182        command_id: DOMString,
183    ) -> DOMString {
184        // Step 1. If command is not supported or has no value, return the empty string.
185        let Some(command) = self.command_if_command_is_supported(&command_id) else {
186            return DOMString::new();
187        };
188        let Some(value) = command.current_value(cx, self) else {
189            return DOMString::new();
190        };
191        // Step 3. If the value override for command is set, return it.
192        self.value_override(&command)
193            .map(|value_override| {
194                // Step 2. If command is "fontSize" and its value override is set,
195                // convert the value override to an integer number of pixels and return the legacy font size for the result.
196                if command == CommandName::FontSize {
197                    value_override
198                        .parse::<i32>()
199                        .map(|parsed| legacy_font_size_for(parsed as f32, self))
200                        .unwrap_or(value_override)
201                } else {
202                    value_override
203                }
204            })
205            // Step 4. Return command's value.
206            .unwrap_or(value)
207    }
208
209    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandenabled()>
210    fn check_support_and_enabled(
211        &self,
212        cx: &mut js::context::JSContext,
213        command_id: &DOMString,
214    ) -> Option<(CommandName, DomRoot<Selection>)> {
215        // Step 2. Return true if command is both supported and enabled, false otherwise.
216        let command = self.command_if_command_is_supported(command_id)?;
217        let selection = self.selection_if_command_is_enabled(cx, command)?;
218        Some((command, selection))
219    }
220
221    /// <https://w3c.github.io/editing/docs/execCommand/#execcommand()>
222    fn exec_command_for_command_id(
223        &self,
224        cx: &mut js::context::JSContext,
225        command_id: DOMString,
226        value: DOMString,
227    ) -> bool {
228        let window = self.window();
229        // Step 3. If command is not supported or not enabled, return false.
230        let Some((command, mut selection)) = self.check_support_and_enabled(cx, &command_id) else {
231            return false;
232        };
233        // Step 4. If command is not in the Miscellaneous commands section:
234        let affected_editing_host = if !is_command_listed_in_miscellaneous_section(command) {
235            // Step 4.1. Let affected editing host be the editing host that is an inclusive ancestor
236            // of the active range's start node and end node, and is not the ancestor of any editing host
237            // that is an inclusive ancestor of the active range's start node and end node.
238            let affected_editing_host = selection
239                .active_range()
240                .expect("Must always have an active range")
241                .CommonAncestorContainer()
242                .editing_host_of()
243                .expect("Must always have an editing host if command is enabled");
244
245            // Step 4.2. Fire an event named "beforeinput" at affected editing host using InputEvent,
246            // with its bubbles and cancelable attributes initialized to true, and its data attribute initialized to null
247            let event = InputEvent::new(
248                window,
249                None,
250                atom!("beforeinput"),
251                true,
252                true,
253                Some(window),
254                0,
255                None,
256                false,
257                "".into(),
258                CanGc::from_cx(cx),
259            );
260            let event = event.upcast::<Event>();
261            // Step 4.3. If the value returned by the previous step is false, return false.
262            if !event.fire(affected_editing_host.upcast(), CanGc::from_cx(cx)) {
263                return false;
264            }
265
266            // Step 4.4. If command is not enabled, return false.
267            let Some(new_selection) = self.selection_if_command_is_enabled(cx, command) else {
268                return false;
269            };
270            selection = new_selection;
271
272            // Step 4.5. Let affected editing host be the editing host that is an inclusive ancestor
273            // of the active range's start node and end node, and is not the ancestor of any editing host
274            // that is an inclusive ancestor of the active range's start node and end node.
275            selection
276                .active_range()
277                .expect("Must always have an active range")
278                .CommonAncestorContainer()
279                .editing_host_of()
280        } else {
281            None
282        };
283
284        // Step 5. Take the action for command, passing value to the instructions as an argument.
285        let result = command.execute(cx, self, &selection, value);
286        // Step 6. If the previous step returned false, return false.
287        if !result {
288            return false;
289        }
290        // Step 7. If the action modified DOM tree, then fire an event named "input" at affected editing
291        // host using InputEvent, with its isTrusted and bubbles attributes initialized to true,
292        // inputType attribute initialized to the mapped value of command, and its data attribute initialized to null.
293        if let Some(affected_editing_host) = affected_editing_host {
294            let event = InputEvent::new(
295                window,
296                None,
297                atom!("input"),
298                true,
299                false,
300                Some(window),
301                0,
302                None,
303                false,
304                mapped_value_of_command(command),
305                CanGc::from_cx(cx),
306            );
307            let event = event.upcast::<Event>();
308            event.set_trusted(true);
309            event.fire(affected_editing_host.upcast(), CanGc::from_cx(cx));
310        }
311
312        // Step 8. Return true.
313        true
314    }
315}
script/dom/execcommand/execcommands.rs

script/dom/execcommand/
execcommands.rs
