get_current_keymaps: comment doc and efficiency change
[conkeror/arlinius.git] / modules / input.js
blob49bceee20c75ea378a5452bfd833bdb13df19137
1 /**
2  * (C) Copyright 2004-2007 Shawn Betts
3  * (C) Copyright 2007-2009 John J. Foerch
4  * (C) Copyright 2007-2008 Jeremy Maitin-Shepard
5  *
6  * Use, modification, and distribution are subject to the terms specified in the
7  * COPYING file.
8 **/
10 require("window.js");
11 require("keymap.js");
12 require("interactive.js");
14 define_variable("key_bindings_ignore_capslock", false,
15     "When true, the case of characters in key bindings will be based "+
16     "only on whether shift was pressed--upper-case if yes, lower-case if "+
17     "no.  Effectively, this overrides the capslock key.  This option has "+
18     "no effect on ordinary typing in input fields.");
20 define_variable("keyboard_key_sequence_help_timeout", 0,
21     "Delay (in millseconds) before the current key sequence prefix is "+
22     "displayed in the minibuffer.");
25 /**
26  * event_clone is used to make a copy of an event which is safe to keep
27  * references to, because it will not reference any DOM trees directly
28  * or indirectly.
29  *
30  * A pertinent question would be, is this needed?  Are there instances
31  * in Conkeror when an event reference is stored across a navigation
32  * boundary or buffer/window closing?
33  */
34 function event_clone (event) {
35     this.type = event.type;
36     this.keyCode = event.keyCode;
37     this.charCode = event.charCode;
38     this.ctrlKey = event.ctrlKey;
39     this.metaKey = event.metaKey;
40     this.altKey = event.altKey;
41     this.shiftKey = event.shiftKey;
42     this.sticky_modifiers = event.sticky_modifiers;
46 /**
47  * event_kill stops an event from being processed by any further handlers.
48  */
49 function event_kill (event) {
50     event.preventDefault();
51     event.stopPropagation();
55 /**
56  * command_event is a special event type that tells input_handle_sequence
57  * to run the given command.
58  */
59 function command_event (command) {
60     this.type = "command";
61     this.command = command;
65 /**
66  * input_state makes an object that holds the state of a single key sequence.
67  * As a small measure of efficiency, these objects get recycled from one
68  * sequence to the next.
69  */
70 function input_state (window) {
71     this.window = window;
72     this.fallthrough = {};
74 input_state.prototype = {
75     continuation: null,
77     // If this is non-null, it is used instead of the current buffer's
78     // keymap.  Used for minibuffer.
79     override_keymap: null //this should be stored in the minibuffer state, right?
83 function input_help_timer_clear (window) {
84     if (window.input.help_timer != null) {
85         timer_cancel(window.input.help_timer);
86         window.input.help_timer = null;
87     }
91 function input_show_partial_sequence (window, I) {
92     if (window.input.help_displayed)
93         window.minibuffer.show(I.key_sequence.join(" "));
94     else {
95         window.input.help_timer = call_after_timeout(function () {
96             window.minibuffer.show(I.key_sequence.join(" "));
97             window.input.help_displayed = true;
98             window.input.help_timer = null;
99         }, keyboard_key_sequence_help_timeout);
100     }
104 define_window_local_hook("keypress_hook", RUN_HOOK_UNTIL_SUCCESS,
105     "A run-until-success hook available for special keypress "+
106     "handling.  Handlers receive as arguments the window, an "+
107     "interactive context, and the real keypress event.  The "+
108     "handler is responsible for stopping event propagation, if "+
109     "that is desired.");
113  * get_current_keymaps returns the keymap stack for the current focus
114  * context of the given window.  This is the top-level keymap stack, not
115  * the stack that represents any on-going key sequence.
116  */
117 function get_current_keymaps (window) {
118     if (window.input.current.override_keymap)
119         return [window.input.current.override_keymap];
120     if (window.buffers.current.override_keymaps[0] !== undefined)
121         return window.buffers.current.override_keymaps;
122     return window.buffers.current.keymaps;
127  * input_handle_sequence is the main handler for all event types which
128  * can be part of a sequence.  It is a coroutine procedure which gets
129  * started and resumed by various EventListeners, some of which have
130  * additional, special tasks.
131  */
132 function input_handle_sequence (event) {
133     try {
134         var window = this;
135         var state = window.input.current;
136         state.continuation = yield CONTINUATION;
137         var I = new interactive_context(window.buffers.current);
138         I.key_sequence = [];
139         I.sticky_modifiers = 0;
140         var keymaps = get_current_keymaps(window);
141 sequence:
142         while (true) {
143             switch (event.type) {
144             case "keydown":
145                 //try the fallthrough predicates in our current keymap
146                 if (keymap_lookup_fallthrough(keymaps[keymaps.length - 1], event)) {
147                     //XXX: need to take account of modifers, too!
148                     state.fallthrough[event.keyCode] = true;
149                 } else
150                     event_kill(event);
151                 break;
152             case "keypress":
153                 window.minibuffer.clear();
154                 window.input.help_displayed = false;
155                 input_help_timer_clear(window);
157                 // prepare the clone
158                 var clone = new event_clone(event);
159                 clone.sticky_modifiers = I.sticky_modifiers;
160                 I.sticky_modifiers = 0;
161                 if (key_bindings_ignore_capslock && clone.charCode) {
162                     let c = String.fromCharCode(clone.charCode);
163                     if (clone.shiftKey)
164                         clone.charCode = c.toUpperCase().charCodeAt(0);
165                     else
166                         clone.charCode = c.toLowerCase().charCodeAt(0);
167                 }
169                 // make the combo string
170                 var combo = format_key_combo(clone);
171                 I.key_sequence.push(combo);
172                 I.combo = combo;
173                 I.event = clone;
175                 if (keypress_hook.run(window, I, event))
176                     break;
178                 var overlay_keymap = I.overlay_keymap;
180                 var binding = (overlay_keymap && keymap_lookup([overlay_keymap], combo, event)) ||
181                     keymap_lookup(keymaps, combo, event);
183                 // kill event for any unbound key, or any bound key which
184                 // is not marked fallthrough
185                 if (!binding || !binding.fallthrough)
186                     event_kill(event);
188                 if (binding) {
189                     if (binding.browser_object != null)
190                         I.binding_browser_object = binding.browser_object;
191                     if (binding.constructor == Array) {
192                         keymaps = binding;
193                         input_show_partial_sequence(window, I);
194                     } else if (binding.command) {
195                         let command = binding.command;
196                         if (I.repeat == command)
197                             command = binding.repeat;
198                         yield call_interactively(I, command);
199                         if (typeof command == "string" &&
200                             interactive_commands.get(command).prefix)
201                         {
202                             keymaps = get_current_keymaps(window); //back to top keymap
203                             input_show_partial_sequence(window, I);
204                             if (binding.repeat)
205                                 I.repeat = command;
206                         } else {
207                             break sequence;
208                         }
209                     } else {
210                         break sequence; //reachable by keypress fallthroughs
211                     }
212                 } else {
213                     window.minibuffer.message(I.key_sequence.join(" ") + " is undefined");
214                     break sequence;
215                 }
216                 break;
217             case "command":
218                 let (command = event.command) {
219                     window.input.help_displayed = false;
220                     input_help_timer_clear(window);
221                     window.minibuffer.clear();
222                     yield call_interactively(I, command);
223                     if (! interactive_commands.get(command).prefix)
224                         break sequence;
225                 }
226                 break;
227             }
228             // should we expect more events?
229             event = null;
230             event = yield SUSPEND;
231         }
232     } catch (e) {
233         dump_error(e);
234     } finally {
235         // sequence is done
236         delete state.continuation;
237     }
241 function input_handle_keydown (event) {
242     if (event.keyCode == 0 ||
243         event.keyCode == vk_name_to_keycode.shift ||
244         event.keyCode == vk_name_to_keycode.control ||
245         event.keyCode == vk_name_to_keycode.alt ||
246         event.keyCode == vk_name_to_keycode.caps_lock)
247         return event_kill(event);
248     var window = this;
249     var state = window.input.current;
250     if (state.continuation)
251         state.continuation(event);
252     else
253         co_call(input_handle_sequence.call(window, event));
257 function input_handle_keypress (event) {
258     if (event.keyCode == 0 && event.charCode == 0 ||
259         event.keyCode == vk_name_to_keycode.caps_lock)
260         return event_kill(event);
261     var window = this;
262     var state = window.input.current;
263     if (state.continuation)
264         state.continuation(event);
265     else
266         co_call(input_handle_sequence.call(window, event));
270 function input_handle_keyup (event) {
271     if (event.keyCode == 0 ||
272         event.keyCode == vk_name_to_keycode.shift ||
273         event.keyCode == vk_name_to_keycode.control ||
274         event.keyCode == vk_name_to_keycode.alt ||
275         event.keyCode == vk_name_to_keycode.caps_lock)
276         return event_kill(event);
277     var window = this;
278     var state = window.input.current;
279     if (state.fallthrough[event.keyCode])
280         delete state.fallthrough[event.keyCode];
281     else
282         event_kill(event);
286 // handler for command_event special events
287 function input_handle_command (event) {
288     var window = this;
289     var state = window.input.current;
290     if (state.continuation)
291         state.continuation(event);
292     else
293         co_call(input_handle_sequence.call(window, event));
297 // handler for special abort event
298 function input_sequence_abort (message) {
299     var window = this;
300     window.input.help_displayed = false;
301     input_help_timer_clear(window);
302     window.minibuffer.clear();
303     if (message)
304         window.minibuffer.show(message);
305     delete window.input.current.continuation;
309 function input_initialize_window (window) {
310     window.input = [new input_state(window)]; // a stack of states
311     window.input.__defineGetter__("current", function () {
312         return this[this.length - 1];
313     });
314     window.input.begin_recursion = function () {
315         this.push(new input_state(window));
316     };
317     window.input.end_recursion = function () {
318         this.pop();
319     };
320     window.input.help_timer = null;
321     window.input.help_displayed = false;
322     //window.addEventListener("keydown", input_handle_keydown, true);
323     window.addEventListener("keypress", input_handle_keypress, true);
324     //window.addEventListener("keyup", input_handle_keyup, true);
325     //TO-DO: mousedown, mouseup, click, dblclick
328 add_hook("window_initialize_hook", input_initialize_window);