smart guides

smart-guides.js

@@ -0,0 +1,56 @@
+window.SmartGuides = {
+  getOptimalSize(textLength) {
+    if (textLength <= 12) {
+      return [92, 144];
+    }
+
+    if (textLength <= 40) {
+      return [52, 88];
+    }
+
+    return [18, 42];
+  },
+
+  getOptimalWeight(fontCategory, size) {
+    if (fontCategory === 'Display') {
+      return size >= 72
+        ? [600, 800]
+        : [500, 700];
+    }
+
+    return size >= 48
+      ? [500, 700]
+      : [400, 600];
+  },
+
+  getOptimalSpacing(size, weight) {
+    if (size >= 96) {
+      return [-6, 0];
+    }
+
+    if (weight >= 700) {
+      return [-2, 1];
+    }
+
+    return [0, 4];
+  },
+
+  getGuideLabel(size, weight, spacing) {
+    if (
+      size >= 72 &&
+      weight >= 600 &&
+      spacing <= 0
+    ) {
+      return 'Display';
+    }
+
+    if (
+      size <= 24 &&
+      spacing >= 0
+    ) {
+      return 'Readable';
+    }
+
+    return 'Balanced';
+  }
+};