Dead simple user list.

[zzz-spline-users.git] / spline / plugins / users / model / __init__.py

diff --git a/spline/plugins/users/model/__init__.py b/spline/plugins/users/model/__init__.py
index f7a30d1..2fd444b 100644 (file)
--- a/spline/plugins/users/model/__init__.py
+++ b/spline/plugins/users/model/__init__.py
@@ -1,3 +1,8 @@
+# encoding: utf8
+import colorsys
+from math import sin, pi
+import random
+
 from sqlalchemy import Column, ForeignKey
 from sqlalchemy.orm import relation
 from sqlalchemy.types import Integer, Unicode
@@ -8,10 +13,84 @@ class User(TableBase):
     __tablename__ = 'users'
     id = Column(Integer, primary_key=True)
     name = Column(Unicode(length=20), nullable=False)
+    unique_identifier = Column(Unicode(length=32), nullable=False)
+
+    def __init__(self, *args, **kwargs):
+        # Generate a unique hash if one isn't provided (which it shouldn't be)
+        if 'unique_identifier' not in kwargs:
+            ident = u''.join(random.choice(u'0123456789abcdef')
+                             for _ in range(32))
+            kwargs['unique_identifier'] = ident
+
+        super(User, self).__init__(*args, **kwargs)
+
+    @property
+    def unique_colors(self):
+        """Returns a list of (width, '#rrggbb') tuples that semi-uniquely
+        identify this user.
+        """
+        width_blob, colors_blob = self.unique_identifier[0:8], \
+                                  self.unique_identifier[8:32]
+
+        widths = []
+        for i in range(4):
+            width_hex = width_blob[i*2:i*2+2]
+            widths.append(int(width_hex, 16))
+        total_width = sum(widths)
+
+        ret = []
+        last_hue = None
+        for i in range(4):
+            raw_hue = int(colors_blob[i*6:i*6+2], 16) / 256.0
+            if last_hue:
+                # Make adjacent hues relatively close together, to avoid green
+                # + purple sorts of clashes.
+                # Minimum distance is 0.1; maximum is 0.35.  Leaves half the
+                # spectrum available for any given color.
+                # Change 0.0–0.1 to -0.35–-0.1, 0.1–0.35
+                hue_offset = raw_hue * 0.5 - 0.25
+                if raw_hue < 0:
+                    raw_hue -= 0.1
+                else:
+                    raw_hue += 0.1
+
+                h = last_hue + raw_hue
+            else:
+                h = raw_hue
+            last_hue = h
+
+            l = int(colors_blob[i*6+2:i*6+4], 16) / 256.0
+            s = int(colors_blob[i*6+4:i*6+6], 16) / 256.0
+
+            # Secondary colors are extremely biased against when picking
+            # randomly from the hue spectrum.
+            # To alleviate this, try to bias hue towards secondary colors.
+            # This adjustment is based purely on experimentation; sin() works
+            # well because hue is periodic, * 6 means each period is 1/3 the
+            # hue spectrum, and the final / 24 is eyeballed
+            h += sin(h * pi * 6) / 24
+
+            # Cap lightness to 0.4 to 0.95, so it's not too close to white or
+            # black
+            l = l * 0.6 + 0.3
+
+            # Cap saturation to 0.5 to 1.0, so the color isn't too gray
+            s = s * 0.6 + 0.3
+
+            r, g, b = colorsys.hls_to_rgb(h, l, s)
+            color = "#{0:02x}{1:02x}{2:02x}".format(
+                int(r * 256),
+                int(g * 256),
+                int(b * 256),
+            )
+
+            ret.append((1.0 * widths[i] / total_width, color))
+
+        return ret
+
 
 class OpenID(TableBase):
     __tablename__ = 'openid'
     openid = Column(Unicode(length=255), primary_key=True)
     user_id = Column(Integer, ForeignKey('users.id'))
     user = relation(User, lazy=False, backref='openids')
-