add keyboard capturing to input

2 files changed, 57 insertions, 4 deletions

diff --git a/input.moon b/input.moon
index fe23fa3..13aa7fe 100644
--- a/input.moon
+++ b/input.moon
@@ -1,6 +1,8 @@
+utf8 = require 'utf8'
 import vec2 from require 'cpml'
 
 class Input
+  NON_TEXT_KEYS = {k,true for k in *{'escape', 'return', 'clear'}}
   new: =>
     @last_keys = {}
     @keys = {}
@@ -8,10 +10,12 @@ class Input
     @last_mouse = vec2!
     @mouse = @last_mouse\clone!
 
+    @text = nil
+
   mouse_down:  (button=1) => @key_down "mouse-#{button}"
   mouse_up:    (button=1) => @key_up   "mouse-#{button}"
   mouse_held:  (button=1) => @key_held "mouse-#{button}"
-  mouse_event: (button=1) => @key_event "mouse-#{button}"
+  mouse_event: (button=1) => (@key_event "mouse-#{button}") or 'hover'
 
   key_down: (key) => @keys[key] and not @last_keys[key]
   key_up:   (key) => not @keys[key] and @last_keys[key]
@@ -20,13 +24,35 @@ class Input
     return 'down' if @key_down key
     return 'up'   if @key_up   key
     return 'held' if @key_held key
-    return 'hover'
+
+  text_capture: =>
+    assert not @text, "keyboard already captured!"
+    @text = ''
+
+  text_release: =>
+    with @text
+      @text = nil
 
   mouse_pos: => @mouse
   mouse_delta: => @mouse - @last_mouse
 
-  keypressed:  (key) => @keys[key] = true
   keyreleased: (key) => @keys[key] = nil
+  keypressed:  (key) =>
+    if @text and not NON_TEXT_KEYS[key]
+      @textinput nil, key
+      return
+
+    @keys[key] = true
+
+  textinput: (str, key) =>
+    return unless @text
+    if str
+      @text ..= str
+    else
+      switch key
+        when 'backspace'
+          offset = utf8.offset @text, -1
+          @text = string.sub @text, 1, offset - 1 if offset
 
   mousemoved: (x, y) => @mouse.x, @mouse.y = x, y
   mousepressed:  (_, _, button) => @keys["mouse-#{button}"] = true
diff --git a/spec/input_spec.moon b/spec/input_spec.moon
index 0828871..81f2d73 100644
--- a/spec/input_spec.moon
+++ b/spec/input_spec.moon
@@ -9,7 +9,7 @@ describe "Input", ->
     assert.is_falsy input\mouse_down!
     assert.is_falsy input\mouse_up!
     assert.is_falsy input\mouse_held!
-    assert.is_falsy input\mouse_event!
+    assert.is_equal 'hover', input\mouse_event!
     assert.is_falsy input\key_down  'w'
     assert.is_falsy input\key_up    'w'
     assert.is_falsy input\key_held  'w'
@@ -94,3 +94,30 @@ describe "Input", ->
     assert.is_falsy input\key_held 'a'
     assert.is_falsy input\key_down 'a'
     assert.is_equal 'up', input\key_event 'a'
+
+  it "allows capturing the keyboard", ->
+    input\text_capture!
+    assert.has_error -> input\text_capture!
+
+    input\textinput 'Helloo'
+    input\keypressed 'backspace'
+    assert.is_falsy input\key_down 'backspace'
+    input\frame!
+
+    assert.is_equal 'Hello', input.text
+    input\textinput ' World'
+    assert.is_equal 'Hello World', input.text
+    assert.is_falsy input\key_down 'backspace'
+
+  it "doesn't capture meta-keys (return and escape)", ->
+    input\keypressed 'return'
+    input\keypressed 'escape'
+
+    assert.is_true input\key_down 'return'
+    assert.is_true input\key_down 'escape'
+
+  it "returns the input' text after releasing the keyboard", ->
+    assert.is_equal 'Hello World', input\text_release!
+
+    input\keypressed 'backspace'
+    assert.is_true input\key_down 'backspace'