documentation/api.md

   1 <!--
   2 This is part of the VimFx documentation.
   3 Copyright Simon Lydell 2015.
   4 See the file README.md for copying conditions.
   5 -->
   6
   7 # Public API
   8
   9 VimFx has a public API. It is intended to be used by:
  10
  11 - Users who prefer to configure things using text files.
  12 - Users who would like to add custom commands.
  13 - Users who would like to set [special options].
  14 - Users who would like to make site-specific customizations.
  15 - Extension authors who would like to extend VimFx.
  16
  17 VimFx users who use the public API should write a so-called [config file].
  18
  19 [special options]: options.md#special-options
  20 [config file]: config-file.md
  21
  22
  23 ## Getting the API
  24
  25 ```js
  26 Components.utils.import('resource://gre/modules/Services.jsm')
  27 let api_url = Services.prefs.getCharPref('extensions.VimFx.api_url')
  28 Components.utils.import(api_url, {}).getAPI(vimfx => {
  29
  30   // Do things with the `vimfx` object here.
  31
  32 })
  33 ```
  34
  35 You might also want to take a look at the [config file bootstrap.js
  36 example][bootstrap.js].
  37
  38 [bootstrap.js]: config-file.md#bootstrapjs
  39
  40
  41 ## API
  42
  43 The following sub-sections assume that you store VimFx’s public API in a
  44 variable called `vimfx`.
  45
  46 [defaults.coffee]: ../extension/lib/defaults.coffee
  47
  48 ### `vimfx.get(pref)`
  49
  50 Gets the value of the VimFx pref `pref`.
  51
  52 You can see all prefs in [defaults.coffee].
  53
  54 ```js
  55 vimfx.get('hint_chars')
  56 vimfx.get('modes.normal.follow')
  57 ```
  58
  59 ### `vimfx.set(pref)`
  60
  61 Sets the value of the VimFx pref `pref`.
  62
  63 You can see all prefs in [defaults.coffee].
  64
  65 ```js
  66 vimfx.set('hint_chars', 'abcdefghijklmnopqrstuvwxyz')
  67 vimfx.set('modes.normal.follow', vimfx.get('modes.normal.follow') + '  e');
  68 ```
  69
  70 ### `vimfx.addCommand(options, fn)`
  71
  72 Creates a new command.
  73
  74 **Note:** This should only be used by users, not by extension authors who wish
  75 to extend VimFx. They should add commands manually to `vimfx.modes` instead.
  76
  77 `options`:
  78
  79 - name: `String`. The name used when accessing the command via
  80   `vimfx.modes[options.mode].commands[options.name]`. It is also used for the
  81   pref used to store the shortcuts for the command:
  82   `` `custom.mode.${options.mode}.${options.name}` ``.
  83 - description: `String`. Shown in the help dialog and VimFx’s settings page in
  84   the Add-ons Manager.
  85 - mode: `String`. Defaults to `'normal'`. The mode to add the command to. The
  86   value has to be one of the keys of `vimfx.modes`.
  87 - category: `String`. Defaults to `'misc'` for Normal mode and `''`
  88   (uncategorized) otherwise. The category to add the command to. The
  89   value has to be one of the keys of `vimfx.categories`.
  90 - order: `Number`. Defaults to putting the command at the end of the category.
  91   The first of the default commands has the order `100` and then they increase
  92   by `100` per command. This allows to put new commands between two already
  93   existing ones.
  94
  95 `fn` is called when the command is activated. See the [`vimfx.modes`]
  96 documentation below for more information.
  97
  98 Note that you have to give the new command a shortcut in VimFx’s settings page
  99 in the Add-ons Manager or set one using `vimfx.set()` to able to use the new
 100 command.
 101
 102 ```js
 103 vimfx.addCommand({
 104   name: 'hello',
 105   description: 'Log Hello World',
 106 }, => {
 107   console.log('Hello World!')
 108 })
 109 ```
 110
 111 [`vimfx.modes`]: #vimfxmodes
 112
 113 ### `vimfx.addOptionOverrides(...rules)` and `vimfx.addKeyOverrides(...rules)`
 114
 115 Takes any number of arguments. Each argument is a rule. The rules are added in
 116 order. The methods may be run multiple times.
 117
 118 A rule is an `Array` of length 2:
 119
 120 - The first item is a function that returns `true` if the rule should be applied
 121   and `false` if not. This is called the matching function.
 122 - The second item is the value that should be used if the rule is applied. This
 123   is called the override.
 124
 125 The rules are tried in the same order they were added. When a matching rule is
 126 found it is applied. No more rules will be applied.
 127
 128 #### `vimfx.addOptionOverrides(...rules)`
 129
 130 The rules are matched any time the value of a VimFx pref is needed.
 131
 132 The matching function receives a [`location`]-like object.
 133
 134 The override is an object whose keys are VimFx pref names and whose values
 135 override the pref in question. Note that all space-separated prefs are parsed
 136 into arrays of strings. `black_list` and `{prev,next}_patterns` are parsed into
 137 arrays of regular expressions.
 138
 139 ```js
 140 vimfx.addOptionOverrides(
 141   [ ({hostname, pathname, hash}) =>
 142     `${hostname}${pathname}${hash}` === 'google.com/',
 143     {prevent_autofocus: false}
 144   ]
 145 )
 146 ```
 147
 148 #### `vimfx.addKeyOverrides(...rules)`
 149
 150 The rules are matched any time you press a key that is not part of the tail of a
 151 multi-key shortcut.
 152
 153 The matching function receives a [`location`]-like object as well as the current
 154 mode.
 155
 156 The override is an array of keys which should not activate VimFx commands but be
 157 sent to the page.
 158
 159 This allows to disable commands on specific sites. To _add_ commands on specific
 160 sites, add them globally and then disable them on all _other_ sites.
 161
 162 ```js
 163 vimfx.addKeyOverrides(
 164   [ location => location.hostname === 'facebook.com',
 165     ['j', 'k']
 166   ]
 167 )
 168 ```
 169
 170 [`location`]: https://developer.mozilla.org/en-US/docs/Web/API/Location
 171
 172 ### `vimfx.on(eventName, listener)`
 173
 174 Runs `listener(data)` when `eventName` is fired.
 175
 176 The following events are available:
 177
 178 - load: Occurs when opening a new tab or navigating to a new URL. `data`:
 179   An object with the following properties:
 180
 181   - vim: The current `vim` instance. Note: This is subject to change. See
 182     [vim.coffee] for now.
 183   - location: A [`location`]-like object.
 184
 185 This can be used to enter a different mode by default on some pages (which can
 186 be used to replace the blacklist option).
 187
 188 ```js
 189 vimfx.on('load', ({vim, location}) => {
 190   if (location.hostname === 'example.com') {
 191     vim.enterMode('insert')
 192   }
 193 })
 194 ```
 195
 196 ### `vimfx.refresh()`
 197
 198 If you make changes to `vimfx.modes` directly you need to call `vimfx.refresh()`
 199 for your changes to take effect.
 200
 201 ### `vimfx.modes`
 202
 203 An object whose keys are mode names and whose values are modes.
 204
 205 A mode is an object with the follwing properties:
 206
 207 - name: `Function`. Returns a human readable name of the mode used in the help
 208   dialog and VimFx’s settings page in the Add-ons Manager.
 209 - order: `Number`. The first of the default modes has the order `0` and then
 210   they increase by `100` per mode. This allows to put new modes between two
 211   already existing ones.
 212 - commands: `Object`. The keys are command names and the values are commands.
 213 - onEnter: `Function`. Called when the mode is entered.
 214 - onLeave: `Function`. Called when the mode is left.
 215 - onInput: `Function`. Called when a key is pressed.
 216
 217 The `on*` methods are called with an object with the following properties:
 218
 219 - vim: An object with state for the current tab. Note: This property is
 220   subject to change. For now, have a look at the [vim.coffee].
 221 - storage: An object unique to the `vim` instance and to the current mode.
 222   Allows to share things between commands of the same mode.
 223
 224 The object passed to `onEnter` also has the following properties:
 225
 226 - args: `Array`. An array of extra arguments passed when entering the mode.
 227
 228 The object passed to `onInput` also has the following properties:
 229
 230 - event: The `keydown` event that activated the command. Note: This property
 231   is subject to change.
 232 - count: `match.count`. `match` is defined below.
 233
 234 It also receives a `match` as the second argument. A `match` has the following
 235 properties:
 236
 237 - type: `String`. It has one of the following values:
 238
 239   - `'full'`: The current keypress fully matches a command shortcut.
 240   - `'partial'`: The current keypress partially matches a command shortcut.
 241   - `'count'`: The current keypress is not part of a command shortcut, but is a
 242     digit and contributes to the count of a future matched command.
 243   - `'none'`: The current keypress is not part of a command shortcut and does
 244     not contribute to a count.
 245
 246 - focus: `String` or `null`. The type of currently focused element (_element_)
 247   plus current pressed key (_key_) combo. You might not want to run commands and
 248   suppress the event if this value is anything other than null. It has one of
 249   the following values:
 250
 251   - `'editable'`: element: a text input or a `contenteditable` element.
 252     key: anything.
 253   - `'activatable'`: element: an “activatable” element (link or button).
 254     key: see the [`activatable_element_keys`] option.
 255   - `'adjustable'`: element: an “adjustable” element (form control or video
 256     player). key: see the [`adjustable_element_keys`] option.
 257   - `'other'`: element: some other kind of element that can receive keystrokes,
 258     for example an element in fullscreen mode. key: anything.
 259   - `null`: the currently focused element does not appear to respond to
 260     keystrokes in any special way.
 261
 262 - command: `null` unless `type` is `'full'`. Then it is the matched command.
 263
 264   This command should usually be run at this point. It is suitable to pass on
 265   the object passed to `onInput` to the command. Some modes might choose to add
 266   extra properties to the object first. (That is favored over passing several
 267   arguments, since it makes it easier for the command to in turn pass the same
 268   data it got on to another command, if needed.)
 269
 270   Usually the return value of the command isn’t used, but that’s up to the mode.
 271
 272 - count: `Number`. The count for the command. `undefined` if no count.
 273
 274 - force: `Boolean`. Indicates if the current key sequence started with
 275   `<force>`.
 276
 277 - keyStr: `String`. The current keypress represented as a string.
 278
 279 - toplevel: `Boolean`. Whether or not the match was a toplevel match in the
 280   shortcut key tree. This is `true` unless the match is part of the tail of a
 281   multi-key shortcut.
 282
 283 `onInput` should return `true` if the current keypress should not be passed on
 284 to the browser and web pages, or `false` otherwise.
 285
 286 A command is an object with the following properties:
 287
 288 - pref: `String`. The pref used to store the shortcuts for the command.
 289 - run: `Function`. Called when the command is activated.
 290 - description: `Function`. Returns a description of the command, shown in the
 291   help dialog and VimFx’s settings page in the Add-ons Manager.
 292 - category: `String`. The category to add the command to. The value has to be
 293   one of the keys of `vimfx.categories`.
 294 - order: `Number`. The first of the default commands has the order `100` and
 295   then they increase by `100` per command. This allows to put new commands
 296   between two already existing ones.
 297
 298 This allows to access all commands and run them, add new commands manually and
 299 add new modes.
 300
 301 ```js
 302 let {commands} = vimfx.modes.normal
 303 // Inside a custom command:
 304 commands.tab_new.run(args)
 305
 306 // Add a new command manually:
 307 vimfx.modes.normal.commands.new_command = {
 308   pref: 'extensions.my_extension.mode.normal.new_command',
 309   category: 'misc',
 310   order: 10000,
 311   description: () => translate('mode.normal.new_command'),
 312   run: args => console.log('New command! args:', args)
 313 }
 314
 315 // Add a new mode:
 316 vimfx.modes.new_mode = {
 317   name: () => translate('mode.new_mode'),
 318   order: 10000,
 319   commands: {},
 320   onEnter(args) {},
 321   onLeave(args) {},
 322   onInput(args, match) {
 323     if (match.type === 'full') {
 324       match.command.run(args)
 325     }
 326     return (match.type !== 'none')
 327   },
 328 }
 329
 330 vimfx.refresh()
 331 ```
 332
 333 Have a look at [modes.coffee] and [commands.coffee] for more information.
 334
 335 [`activatable_element_keys`]: options.md#activatable_element_keys
 336 [`adjustable_element_keys`]: options.md#adjustable_element_keys
 337 [vim.coffee]: ../extension/lib/vim.coffee
 338 [modes.coffee]: ../extension/lib/modes.coffee
 339 [commands.coffee]: ../extension/lib/commands.coffee
 340
 341 ### `vimfx.categories`
 342
 343 An object whose keys are category names and whose values are categories.
 344
 345 A category is an object with the follwing properties:
 346
 347 - name: `Function`. Returns a human readable name of the category used in the
 348   help dialog and VimFx’s settings page in the Add-ons Manager. Users adding
 349   custom category could simply return a string; extension authors are encouraged
 350   to look up the name from a locale file.
 351 - order: `Number`. The first of the default categories is the “uncategorized”
 352   category. It has the order `0` and then they increase by `100` per category.
 353   This allows to put new categories between two already existing ones.
 354
 355 ```js
 356 let {categories} = vimfx
 357
 358 // Add new category.
 359 categories.custom = {
 360   name: () => 'Custom commands',
 361   order: 10000,
 362 }
 363
 364 // Swap the order of the Location and Tabs categories.
 365 ;[categories.location.order, categories.tabs.order] =
 366   [categories.tabs.order, categories.location.order]
 367 ```
 368
 369
 370 ## Stability
 371
 372 The public API is currently **experimental** and therefore **unstable.** Things
 373 might break with new VimFx versions.
 374
 375 As soon as VimFx 1.0.0 is released backwards compatibility will be a priority
 376 and won’t be broken until VimFx 2.0.0.