fix: Shopping List Label Text Color (#4302)

frontend/components/Domain/ShoppingList/MultiPurposeLabel.vue

@@ -8,8 +8,7 @@
 
 <script lang="ts">
 import { computed, defineComponent } from "@nuxtjs/composition-api";
-// @ts-ignore missing color types
-import Color from "@sphinxxxx/color-conversion";
+import { getTextColor } from "~/composables/use-text-color";
 import { MultiPurposeLabelSummary } from "~/lib/api/types/recipe";
 
 
@@ -21,44 +20,7 @@ export default defineComponent({
     },
   },
   setup(props) {
-    const textColor = computed(() => {
-      if (!props.label.color) {
-        return "black";
-      }
-
-      return pickTextColorBasedOnBgColorAdvanced(props.label.color, "white", "black");
-    });
-
-    /*
-    Function to pick the text color based on the background color.
-
-    Based on -> https://stackoverflow.com/questions/3942878/how-to-decide-font-color-in-white-or-black-depending-on-background-color
-    */
-    const ACCESSIBILITY_THRESHOLD = 0.179;
-
-    function pickTextColorBasedOnBgColorAdvanced(bgColor: string, lightColor: string, darkColor: string) {
-      try {
-        const color = new Color(bgColor);
-
-        // if opacity is less than 0.3 always return dark color
-        if (color._rgba[3] < 0.3) {
-          return darkColor;
-        }
-
-        const uicolors = [color._rgba[0] / 255, color._rgba[1] / 255, color._rgba[2] / 255];
-        const c = uicolors.map((col) => {
-          if (col <= 0.03928) {
-            return col / 12.92;
-          }
-          return Math.pow((col + 0.055) / 1.055, 2.4);
-        });
-        const L = 0.2126 * c[0] + 0.7152 * c[1] + 0.0722 * c[2];
-        return L > ACCESSIBILITY_THRESHOLD ? darkColor : lightColor;
-      } catch (error) {
-        console.warn(error);
-        return "black";
-      }
-    }
+    const textColor = computed(() => getTextColor(props.label.color));
 
     return {
       textColor,

frontend/composables/use-text-color.ts

@@ -0,0 +1,39 @@
+// @ts-ignore missing color types
+import Color from "@sphinxxxx/color-conversion";
+
+const LIGHT_COLOR = "white";
+const DARK_COLOR = "black";
+const ACCESSIBILITY_THRESHOLD = 0.179;
+
+/*
+Function to pick the text color based on the background color.
+
+Based on -> https://stackoverflow.com/questions/3942878/how-to-decide-font-color-in-white-or-black-depending-on-background-color
+*/
+export function getTextColor(bgColor: string | undefined): string {
+  if (!bgColor) {
+    return DARK_COLOR;
+  }
+
+  try {
+    const color = new Color(bgColor);
+
+    // if opacity is less than 0.3 always return dark color
+    if (color._rgba[3] < 0.3) {
+      return DARK_COLOR;
+    }
+
+    const uicolors = [color._rgba[0] / 255, color._rgba[1] / 255, color._rgba[2] / 255];
+    const c = uicolors.map((col) => {
+      if (col <= 0.03928) {
+        return col / 12.92;
+      }
+      return Math.pow((col + 0.055) / 1.055, 2.4);
+    });
+    const L = 0.2126 * c[0] + 0.7152 * c[1] + 0.0722 * c[2];
+    return L > ACCESSIBILITY_THRESHOLD ? DARK_COLOR : LIGHT_COLOR;
+  } catch (error) {
+    console.warn(error);
+    return DARK_COLOR;
+  }
+}

frontend/pages/shopping-lists/_id.vue

@@ -58,7 +58,15 @@
       <div v-else>
         <div v-for="(value, key) in itemsByLabel" :key="key" class="mb-6">
           <div class="text-left">
-            <v-btn :color="getLabelColor(value[0]) ? getLabelColor(value[0]) : '#959595'">{{ key }}</v-btn>
+            <v-btn
+              :color="getLabelColor(value[0]) ? getLabelColor(value[0]) : '#959595'"
+              :style="{
+                'color': getTextColor(getLabelColor(value[0])),
+                'letter-spacing': 'normal',
+              }"
+            >
+              {{ key }}
+          </v-btn>
           </div>
           <v-divider/>
           <draggable :value="value" handle=".handle" delay="250" :delay-on-touch-only="true" @start="loadingCounter += 1" @end="loadingCounter -= 1" @input="updateIndexUncheckedByLabel(key, $event)">
@@ -298,6 +306,7 @@ import ShoppingListItemEditor from "~/components/Domain/ShoppingList/ShoppingLis
 import { useFoodStore, useLabelStore, useUnitStore } from "~/composables/store";
 import { useShoppingListItemActions } from "~/composables/use-shopping-list-item-actions";
 import { useShoppingListPreferences } from "~/composables/use-users/preferences";
+import { getTextColor } from "~/composables/use-text-color";
 import { uuid4 } from "~/composables/use-utils";
 
 type CopyTypes = "plain" | "markdown";
@@ -1085,6 +1094,7 @@ export default defineComponent({
       allUsers,
       currentUserId,
       updateSettings,
+      getTextColor,
     };
   },
   head() {