From 0cac1aa7af508dc3e4f582a3fad75fa8d5c2e9af Mon Sep 17 00:00:00 2001
From: Cyberarm <matthewlikesrobots@gmail.com>
Date: Thu, 22 Sep 2022 09:05:44 -0500
Subject: [PATCH] WIP: Initial GUI work

---
 examples/gui_state.cr                         |  29 ++
 src/cyberarm_engine.cr                        |   2 +-
 src/cyberarm_engine/ui/element.cr             | 320 ++++++++++++++++++
 .../ui/{style.cr => style_manager.cr}         |   2 +-
 4 files changed, 351 insertions(+), 2 deletions(-)
 create mode 100644 examples/gui_state.cr
 rename src/cyberarm_engine/ui/{style.cr => style_manager.cr} (89%)

diff --git a/examples/gui_state.cr b/examples/gui_state.cr
new file mode 100644
index 0000000..1b6ecc8
--- /dev/null
+++ b/examples/gui_state.cr
@@ -0,0 +1,29 @@
+require "./../src/cyberarm_engine"
+
+class Window < CyberarmEngine::Window
+  class State < CyberarmEngine::GuiState
+    @options : Int32
+
+    def setup
+      stack(width: 100, height: 100.0) do
+        background 0xff_353535
+
+        title "Hello World"
+      end
+    end
+
+    def draw
+      Gosu.draw_rect(0, 0, window.width, window.height, 0xff_353535)
+    end
+
+    def needs_cursor?
+      true
+    end
+  end
+
+  def setup
+    push_state(State.new(3))
+  end
+end
+
+Window.new.show
\ No newline at end of file
diff --git a/src/cyberarm_engine.cr b/src/cyberarm_engine.cr
index 0eb2972..f02af8b 100644
--- a/src/cyberarm_engine.cr
+++ b/src/cyberarm_engine.cr
@@ -10,7 +10,7 @@ require "./cyberarm_engine/text"
 require "./cyberarm_engine/ui/dsl"
 require "./cyberarm_engine/ui/gui_state"
 require "./cyberarm_engine/ui/event"
-require "./cyberarm_engine/ui/style"
+require "./cyberarm_engine/ui/style_manager"
 require "./cyberarm_engine/ui/theme"
 require "./cyberarm_engine/ui/element"
 require "./cyberarm_engine/ui/elements/container"
diff --git a/src/cyberarm_engine/ui/element.cr b/src/cyberarm_engine/ui/element.cr
index e69de29..fdfc333 100644
--- a/src/cyberarm_engine/ui/element.cr
+++ b/src/cyberarm_engine/ui/element.cr
@@ -0,0 +1,320 @@
+module CyberarmEngine
+  class Element
+    def initialize(@parent, @gui_state : CyberarmEngine::GuiState, @style = StyleManager.new(StyleManager::DEFAULT_STYLES), @tag : String? = nil, @tip : String = "", &@block)
+      @focus = true
+      @enabled = true
+      @visible = true
+      @element_visible = true
+
+      @debug_color = Gosu::Color::RED
+
+      @width = 0
+      @height = 0
+
+      @style_event = :default
+
+      @style.stylize
+
+      default_events
+
+      gui_state.request_focus(style) if @style.autofocus?
+    end
+
+    def default_events
+      %i[left middle right].each do |button|
+        event(:"#{button}_mouse_button")
+        event(:"released_#{button}_mouse_button")
+        event(:"clicked_#{button}_mouse_button")
+        event(:"holding_#{button}_mouse_button")
+      end
+
+      event(:mouse_wheel_up)
+      event(:mouse_wheel_down)
+
+      event(:enter)
+      event(:hover)
+      event(:leave)
+
+      event(:focus)
+      event(:blur)
+
+      event(:changed)
+    end
+
+    def enter(sender)
+      @style.focus = false unless Gosu.button_down?(Gosu::MS_LEFT)
+
+      @style.stylize
+
+      :handled
+    end
+
+    def left_mouse_button(sender, x, y)
+      @style.focus = true
+
+      @style.stylize
+
+      @gui_state.focus = self
+
+      :handled
+    end
+
+    def released_left_mouse_button(sender, x, y)
+      @block.not_nil!.call(self) if @block && @enabled && !is_a?(Container)
+
+      :handled
+    end
+
+    def leave(sender)
+      @style.stylize
+
+      :handled
+    end
+
+    def blur
+      @style.focus = false
+
+      @style.stylize
+
+      :handled
+    end
+
+    def enabled=(boolean : Bool)
+      @style.enabled = boolean
+
+      recalculate
+
+      @style.enabled?
+    end
+
+    def enabled?
+      @style.enabled?
+    end
+
+    def visible?
+      @style.visible?
+    end
+
+    def element_visible?
+      @element_visible
+    end
+
+    def toggle
+      @style.visible = !@style.visible
+
+      gui_state.request_recalculate
+    end
+
+    def show
+      already_visible = visible?
+
+      @style.visible = true
+
+      gui_state.request_recalculate unless already_visible
+    end
+
+    def hide
+      already_hidden = visible?
+
+      @style.visible = true
+
+      gui_state.request_recalculate if already_hidden
+    end
+
+    def draw
+      return unless visible?
+      return unless element_visible?
+
+      @style.render
+
+      render
+    end
+
+    def debug_draw
+    end
+
+    def update
+    end
+
+    def button_down(id)
+    end
+
+    def button_up(id)
+    end
+
+    def draggable?(button)
+      false
+    end
+
+    def render
+    end
+
+    def hit(x, y)
+      x.between?(@style.x, @style.x + width) &&
+      y.between?(@style.y, @style.y + height)
+    end
+
+    def width
+      if visible?
+        inner_width + @width
+      else
+        0
+      end
+    end
+
+    def content_width
+      @width
+    end
+
+    def noncontent_width
+      (inner_width + outer_width) - width
+    end
+
+    def outer_width
+      @style.margin_left + width + @style.margin_right
+    end
+
+    def inner_width
+      (@style.border_thickness_left + @style.padding_left) + (@style.padding_right + @style.border_thickness_right)
+    end
+
+
+    def height
+      if visible?
+        inner_height + @height
+      else
+        0
+      end
+    end
+
+    def content_height
+      @height
+    end
+
+    def noncontent_height
+      (inner_height + outer_height) - height
+    end
+
+    def outer_height
+      @style.margin_top + height + @style.margin_bottom
+    end
+
+    def inner_height
+      (@style.border_thickness_top + @style.padding_top) + (@style.padding_bottom + @style.border_thickness_bottom)
+    end
+
+    def scroll_width
+      @children.sum { |c| c.outer_width }
+    end
+
+    def scroll_height
+      if is_a?(CyberarmEngine::Element::Flow)
+        return 0 if @children.size.zero?
+
+        pairs = [] of Array(Element)
+        sorted_children = @children.sort_by { |c| c.style.y }
+        array = [] of Element
+        y_position = sorted_children.first.style.y
+
+        sorted_children.each do |child|
+          unless child.style.y == y_position
+            y_position = child.style.y
+            pairs << array
+            array.clear
+          end
+
+          array << child
+        end
+
+        pairs << array unless pairs.last == array
+
+        pairs.sum { |pair| pair.map { |pr| pr.outer_height}.max } + @style.padding_bottom + @style.border_thickness_bottom
+      else
+        @children.sum { |c| c.outer_height } + @style.padding_bottom + @style.border_thickness_bottom
+      end
+    end
+
+    def max_scroll_width
+      scroll_width - outer_width
+    end
+
+    def max_scroll_height
+      scroll_height - outer_height
+    end
+
+    def dimensional_size(size, dimension)
+      raise "dimension must be either :width or :height" unless %i[width height].include?(dimension)
+
+      new_size = if size.is_a?(Numeric) && size.between?(0.0, 1.0)
+        (@parent.send(:"content_#{dimension}") * size).floor - send(:"noncontent_#{dimension}").floor
+      else
+        size
+      end
+
+      if @parent && @style.fill # Handle fill behavior
+        if dimension == :width && @parent.is_a?(Flow)
+          return space_available_width - noncontent_width
+
+        elsif dimension == :height && @parent.is_a?(Stack)
+          return space_available_height - noncontent_height
+        end
+
+      else # Handle min_width/height and max_width/height
+        return @style.send(:"min_#{dimension}") if @style.send(:"min_#{dimension}") && new_size < @style.send(:"min_#{dimension}")
+        return @style.send(:"max_#{dimension}") if @style.send(:"max_#{dimension}") && new_size > @style.send(:"max_#{dimension}")
+      end
+
+      new_size
+    end
+
+
+    def space_available_width
+      # TODO: This may get expensive if there are a lot of children, probably should cache it somehow
+      fill_siblings = @parent.children.select { |c| c.style.fill }.count.to_f # include self since we're dividing
+
+      available_space = ((@parent.content_width - (@parent.children.reject { |c| c.style.fill }).map(&:outer_width).sum) / fill_siblings)
+      (available_space.nan? || available_space.infinite?) ? 0 : available_space.floor # The parent element might not have its dimensions, yet.
+    end
+
+    def space_available_height
+      # TODO: This may get expensive if there are a lot of children, probably should cache it somehow
+      fill_siblings = @parent.children.select { |c| c.style.fill }.count.to_f # include self since we're dividing
+
+      available_space = ((@parent.content_height - (@parent.children.reject { |c| c.style.fill }).map(&:outer_height).sum) / fill_siblings)
+      (available_space.nan? || available_space.infinite?) ? 0 : available_space.floor # The parent element might not have its dimensions, yet.
+    end
+
+    def root_element?
+      @parent.nil?
+    end
+
+    def focus(unknown)
+      warn "#{self.class}#focus was not overridden!"
+
+      :handled
+    end
+
+    def recalculate
+      raise "#{self.class}#recalculate was not overridden!"
+    end
+
+    def reposition
+    end
+
+    def value
+      raise "#{self.class}#value was not overridden!"
+    end
+
+    def value=(_value)
+      raise "#{self.class}#value= was not overridden!"
+    end
+
+    def to_s
+      "#{self.class} x=#{x} y=#{y} width=#{width} height=#{height} value=#{value.is_a?(String) ? "\"#{value}\"" : value}"
+    end
+
+    def inspect
+      to_s
+    end
+  end
+end
diff --git a/src/cyberarm_engine/ui/style.cr b/src/cyberarm_engine/ui/style_manager.cr
similarity index 89%
rename from src/cyberarm_engine/ui/style.cr
rename to src/cyberarm_engine/ui/style_manager.cr
index 514fc28..8551208 100644
--- a/src/cyberarm_engine/ui/style.cr
+++ b/src/cyberarm_engine/ui/style_manager.cr
@@ -1,5 +1,5 @@
 module CyberarmEngine
-  class Style
+  class StyleManager
     def initialize(@x, @y, @z, @width, @height, @color, @background, @margin, @padding, @border_thickness, @border_color, @border_radius)
     end
   end