Add colors attribute to Bar class

This list lets you specify a set of colors that the bar should be painted with
depending on the percentage the bar is filled

erynrl/interface/bar.py

@@ -1,12 +1,37 @@
 # Eryn Wells <eryn@erynwells.me>
 
+from typing import List, Optional, Tuple
+
 from . import color
 from ..geometry import Point
 
 class Bar:
-    def __init__(self, *, position: Point, width: int):
+    '''A bar that expresses a percentage.'''
+
+    def __init__(self, *, position: Point, width: int, colors: Optional[List[Tuple[float, color.Color]]] = None):
+        '''
+        Instantiate a new Bar
+
+        Arguments
+        ---------
+        position : Point
+            The position within a console to render this bar
+        width : int
+            The length of the bar in tiles
+        colors : List[Tuple[float, color.Color]]
+            A list of two-tuples specifying a percentage and color to draw the bar. If the bar is less than or equal to
+            the specified percentage, that color will be chosen. For example, if the bar is 45% filled, and this colors
+            array is specified:
+
+            ```
+            [(0.25, RED), (0.5, ORANGE), (0.75, YELLOW), (1.0, GREEN)]
+            ```
+
+            The bar will be painted `ORANGE` because 45% is greater than 25% and less than 50%.
+        '''
         self.position = position
         self.width = width
+        self.colors = sorted(colors, key=lambda c: c[0]) if colors is not None else []
 
         self._percent_filled = 1.0
 
@@ -20,8 +45,18 @@ class Bar:
         self._percent_filled = min(1, max(0, value))
 
     def render_to_console(self, console):
-        console.draw_rect(x=self.position.x, y=self.position.y, width=self.width, height=1, ch=1, bg=color.GREY10)
+        '''Draw this bar to the console'''
+        # Draw the background first
+        console.draw_rect(x=self.position.x, y=self.position.y, width=self.width, height=1, ch=1, bg=color.GREY12)
+
+        percent_filled = self._percent_filled
+        if percent_filled > 0:
+            for color_spec in self.colors:
+                if percent_filled <= color_spec[0]:
+                    bar_color = color_spec[1]
+                    break
+            else:
+                bar_color = color.GREY50
 
-        if self._percent_filled > 0:
             filled_width = round(self._percent_filled * self.width)
-            console.draw_rect(x=self.position.x, y=self.position.y, width=filled_width, height=1, ch=1, bg=color.GREY50)
+            console.draw_rect(x=self.position.x, y=self.position.y, width=filled_width, height=1, ch=1, bg=bar_color)