Add utility for turning keymaps into characters mappings.

lib/util/keyutil.js

@@ -3,7 +3,9 @@ var util = require('util')
 var adb = require('adbkit')
 var Promise = require('bluebird')
 
-module.exports.parseKeyCharacterMap = function(stream) {
+var keyutil = module.exports = Object.create(null)
+
+keyutil.parseKeyCharacterMap = function(stream) {
   var resolver = Promise.defer()
     , state = 'type_t'
     , keymap = {
@@ -413,6 +415,7 @@ module.exports.parseKeyCharacterMap = function(stream) {
         if ((char >= '0' && char <= '9') ||
             (char >= 'a' && char <= 'f')) {
           lastBehavior.value += parseInt(char, 16)
+          lastBehavior.value = String.fromCharCode(lastBehavior.value)
           state = 'filter_behavior_literal_end'
           return true
         }
@@ -455,3 +458,115 @@ module.exports.parseKeyCharacterMap = function(stream) {
     stream.removeListener('end', endListener)
   })
 }
+
+keyutil.namedKey = function(name) {
+  var key = adb.Keycode['KEYCODE_' + name]
+  if (key === void 0) {
+    throw new Error(util.format('Unknown key "%s"', name))
+  }
+  return key
+}
+
+keyutil.buildCharMap = function(keymap) {
+  var charmap = Object.create(null)
+
+  keymap.keys.forEach(function(key) {
+    key.rules.forEach(function(rule) {
+      var combination = {
+        key: keyutil.namedKey(key.key)
+      , modifiers: []
+      , complexity: 0
+      }
+
+      var shouldHandle = rule.modifiers.every(function(modifier) {
+        switch (modifier.type) {
+          case 'label':
+            return false // ignore
+          case 'base':
+            return true
+          case 'shift':
+          case 'lshift':
+            combination.modifiers.push(adb.Keycode.KEYCODE_SHIFT_LEFT)
+            combination.complexity += 10
+            return true
+          case 'rshift':
+            combination.modifiers.push(adb.Keycode.KEYCODE_SHIFT_RIGHT)
+            combination.complexity += 10
+            return true
+          case 'alt':
+          case 'lalt':
+            combination.modifiers.push(adb.Keycode.KEYCODE_ALT_LEFT)
+            combination.complexity += 20
+            return true
+          case 'ralt':
+            combination.modifiers.push(adb.Keycode.KEYCODE_ALT_RIGHT)
+            combination.complexity += 20
+            return true
+          case 'ctrl':
+          case 'lctrl':
+            combination.modifiers.push(adb.Keycode.KEYCODE_CTRL_LEFT)
+            combination.complexity += 20
+            return true
+          case 'rctrl':
+            combination.modifiers.push(adb.Keycode.KEYCODE_CTRL_RIGHT)
+            combination.complexity += 20
+            return true
+          case 'meta':
+          case 'lmeta':
+            combination.modifiers.push(adb.Keycode.KEYCODE_META_LEFT)
+            combination.complexity += 20
+            return true
+          case 'rmeta':
+            combination.modifiers.push(adb.Keycode.KEYCODE_META_RIGHT)
+            combination.complexity += 20
+            return true
+          case 'sym':
+            combination.modifiers.push(adb.Keycode.KEYCODE_SYM)
+            combination.complexity += 10
+            return true
+          case 'fn':
+            combination.modifiers.push(adb.Keycode.KEYCODE_FUNCTION)
+            combination.complexity += 30
+            return true
+          case 'capslock':
+            combination.modifiers.push(adb.Keycode.KEYCODE_CAPS_LOCK)
+            combination.complexity += 30
+            return true
+          case 'numlock':
+            combination.modifiers.push(adb.Keycode.KEYCODE_NUM_LOCK)
+            combination.complexity += 30
+            return true
+          case 'scrolllock':
+            combination.modifiers.push(adb.Keycode.KEYCODE_SCROLL_LOCK)
+            combination.complexity += 30
+            return true
+        }
+      })
+
+      if (!shouldHandle) {
+        return
+      }
+
+      rule.behaviors.forEach(function(behavior) {
+        switch (behavior.type) {
+          case 'literal':
+            if (!charmap[behavior.value]) {
+              charmap[behavior.value] = [combination]
+            }
+            else {
+              charmap[behavior.value].push(combination)
+
+              // Could be more efficient, but we only have 1-4 combinations
+              // per key, so we don't really care.
+              charmap[behavior.value].sort(function(a, b) {
+                return a.complexity - b.complexity
+              })
+            }
+            break
+        }
+      })
+    })
+  })
+
+  return charmap
+}