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 js::context::JSContext;
6use script_bindings::inheritance::Castable;
7
8use crate::dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
9use crate::dom::bindings::codegen::Bindings::HTMLElementBinding::HTMLElementMethods;
10use crate::dom::bindings::codegen::Bindings::RangeBinding::RangeMethods;
11use crate::dom::bindings::root::DomRoot;
12use crate::dom::bindings::str::DOMString;
13use crate::dom::document::Document;
14use crate::dom::event::Event;
15use crate::dom::event::inputevent::InputEvent;
16use crate::dom::execcommand::basecommand::CommandName;
17use crate::dom::execcommand::commands::fontsize::maybe_normalize_pixels;
18use crate::dom::html::htmlelement::HTMLElement;
19use crate::dom::node::Node;
20use crate::dom::selection::Selection;
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 JSContext,
80        command_name: CommandName,
81    ) -> Option<DomRoot<Selection>> {
82        let selection = self.GetSelection(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        if !command_name.is_enabled(cx, &range, &start_container_editing_host) {
104            return None;
105        }
106
107        // Some commands are only enabled if the editing host is *not* in plaintext-only state.
108        if !command_name.is_enabled_in_plaintext_only_state() &&
109            (start_container_editing_host.is_in_plaintext_only_state() ||
110                end_container_editing_host.is_in_plaintext_only_state())
111        {
112            None
113        } else {
114            Some(selection)
115        }
116    }
117
118    /// <https://w3c.github.io/editing/docs/execCommand/#supported>
119    fn command_if_command_is_supported(&self, command_id: &DOMString) -> Option<CommandName> {
120        // https://w3c.github.io/editing/docs/execCommand/#methods-to-query-and-execute-commands
121        // > All of these methods must treat their command argument ASCII case-insensitively.
122        Some(match &*command_id.str().to_lowercase() {
123            "backcolor" => CommandName::BackColor,
124            "bold" => CommandName::Bold,
125            "createlink" => CommandName::CreateLink,
126            "delete" => CommandName::Delete,
127            "defaultparagraphseparator" => CommandName::DefaultParagraphSeparator,
128            "fontname" => CommandName::FontName,
129            "fontsize" => CommandName::FontSize,
130            "forecolor" => CommandName::ForeColor,
131            "hilitecolor" => CommandName::HiliteColor,
132            "insertparagraph" => CommandName::InsertParagraph,
133            "italic" => CommandName::Italic,
134            "removeformat" => CommandName::RemoveFormat,
135            "strikethrough" => CommandName::Strikethrough,
136            "stylewithcss" => CommandName::StyleWithCss,
137            "subscript" => CommandName::Subscript,
138            "superscript" => CommandName::Superscript,
139            "underline" => CommandName::Underline,
140            "unlink" => CommandName::Unlink,
141            _ => return None,
142        })
143    }
144}
145
146pub(crate) trait DocumentExecCommandSupport {
147    fn is_command_supported(&self, command_id: DOMString) -> bool;
148    fn is_command_indeterminate(&self, cx: &mut JSContext, command_id: DOMString) -> bool;
149    fn command_state_for_command(&self, cx: &mut JSContext, command_id: DOMString) -> bool;
150    fn command_value_for_command(&self, cx: &mut JSContext, command_id: DOMString) -> DOMString;
151    fn check_support_and_enabled(
152        &self,
153        cx: &mut JSContext,
154        command_id: &DOMString,
155    ) -> Option<(CommandName, DomRoot<Selection>)>;
156    fn exec_command_for_command_id(
157        &self,
158        cx: &mut JSContext,
159        command_id: DOMString,
160        value: DOMString,
161    ) -> bool;
162}
163
164impl DocumentExecCommandSupport for Document {
165    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandsupported()>
166    fn is_command_supported(&self, command_id: DOMString) -> bool {
167        self.command_if_command_is_supported(&command_id).is_some()
168    }
169
170    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandindeterm()>
171    fn is_command_indeterminate(&self, cx: &mut JSContext, command_id: DOMString) -> bool {
172        // Step 1. If command is not supported or has no indeterminacy, return false.
173        // Step 2. Return true if command is indeterminate, otherwise false.
174        self.command_if_command_is_supported(&command_id)
175            .is_some_and(|command| command.is_indeterminate(cx, self))
176    }
177
178    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandstate()>
179    fn command_state_for_command(&self, cx: &mut JSContext, command_id: DOMString) -> bool {
180        // Step 1. If command is not supported or has no state, return false.
181        let Some(command) = self.command_if_command_is_supported(&command_id) else {
182            return false;
183        };
184        let Some(state) = command.current_state(cx, self) else {
185            return false;
186        };
187        // Step 2. If the state override for command is set, return it.
188        // Step 3. Return true if command's state is true, otherwise false.
189        self.state_override(&command).unwrap_or(state)
190    }
191
192    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandvalue()>
193    fn command_value_for_command(&self, cx: &mut JSContext, command_id: DOMString) -> DOMString {
194        // Step 1. If command is not supported or has no value, return the empty string.
195        let Some(command) = self.command_if_command_is_supported(&command_id) else {
196            return DOMString::new();
197        };
198        let Some(value) = command.current_value(cx, self) else {
199            return DOMString::new();
200        };
201        // Step 3. If the value override for command is set, return it.
202        self.value_override(&command)
203            .map(|value_override| {
204                // Step 2. If command is "fontSize" and its value override is set,
205                // convert the value override to an integer number of pixels and return the legacy font size for the result.
206                if command == CommandName::FontSize {
207                    maybe_normalize_pixels(&value_override, self).unwrap_or(value_override)
208                } else {
209                    value_override
210                }
211            })
212            // Step 4. Return command's value.
213            .unwrap_or(value)
214    }
215
216    /// <https://w3c.github.io/editing/docs/execCommand/#querycommandenabled()>
217    fn check_support_and_enabled(
218        &self,
219        cx: &mut JSContext,
220        command_id: &DOMString,
221    ) -> Option<(CommandName, DomRoot<Selection>)> {
222        // Step 2. Return true if command is both supported and enabled, false otherwise.
223        let command = self.command_if_command_is_supported(command_id)?;
224        let selection = self.selection_if_command_is_enabled(cx, command)?;
225        Some((command, selection))
226    }
227
228    /// <https://w3c.github.io/editing/docs/execCommand/#execcommand()>
229    fn exec_command_for_command_id(
230        &self,
231        cx: &mut JSContext,
232        command_id: DOMString,
233        value: DOMString,
234    ) -> bool {
235        let window = self.window();
236        // Step 3. If command is not supported or not enabled, return false.
237        let Some((command, mut selection)) = self.check_support_and_enabled(cx, &command_id) else {
238            return false;
239        };
240        // Step 4. If command is not in the Miscellaneous commands section:
241        let affected_editing_host = if !is_command_listed_in_miscellaneous_section(command) {
242            // Step 4.1. Let affected editing host be the editing host that is an inclusive ancestor
243            // of the active range's start node and end node, and is not the ancestor of any editing host
244            // that is an inclusive ancestor of the active range's start node and end node.
245            let Some(affected_editing_host) = selection
246                .active_range()
247                .expect("Must always have an active range")
248                .CommonAncestorContainer()
249                .editing_host_of()
250            else {
251                return false;
252            };
253
254            // Step 4.2. Fire an event named "beforeinput" at affected editing host using InputEvent,
255            // with its bubbles and cancelable attributes initialized to true, and its data attribute initialized to null
256            let event = InputEvent::new(
257                cx,
258                window,
259                None,
260                atom!("beforeinput"),
261                true,
262                true,
263                Some(window),
264                0,
265                None,
266                false,
267                "".into(),
268            );
269            let event = event.upcast::<Event>();
270            // Step 4.3. If the value returned by the previous step is false, return false.
271            if !event.fire(cx, affected_editing_host.upcast()) {
272                return false;
273            }
274
275            // Step 4.4. If command is not enabled, return false.
276            let Some(new_selection) = self.selection_if_command_is_enabled(cx, command) else {
277                return false;
278            };
279            selection = new_selection;
280
281            // Step 4.5. Let affected editing host be the editing host that is an inclusive ancestor
282            // of the active range's start node and end node, and is not the ancestor of any editing host
283            // that is an inclusive ancestor of the active range's start node and end node.
284            selection
285                .active_range()
286                .expect("Must always have an active range")
287                .CommonAncestorContainer()
288                .editing_host_of()
289        } else {
290            None
291        };
292
293        // Step 5. Take the action for command, passing value to the instructions as an argument.
294        let result = command.execute(cx, self, &selection, value);
295        // Step 6. If the previous step returned false, return false.
296        if !result {
297            return false;
298        }
299        // Step 7. If the action modified DOM tree, then fire an event named "input" at affected editing
300        // host using InputEvent, with its isTrusted and bubbles attributes initialized to true,
301        // inputType attribute initialized to the mapped value of command, and its data attribute initialized to null.
302        if let Some(affected_editing_host) = affected_editing_host {
303            let event = InputEvent::new(
304                cx,
305                window,
306                None,
307                atom!("input"),
308                true,
309                false,
310                Some(window),
311                0,
312                None,
313                false,
314                mapped_value_of_command(command),
315            );
316            let event = event.upcast::<Event>();
317            event.set_trusted(true);
318            event.fire(cx, affected_editing_host.upcast());
319        }
320
321        // Step 8. Return true.
322        true
323    }
324}
script/dom/execcommand/execcommands.rs

script/dom/execcommand/
execcommands.rs
