Make calendar cells clickable and improve mood heatmap colors

assets/css/app.css

@@ -417,11 +417,19 @@ button {
     width: 0.8rem;
     height: 0.8rem;
     border-radius: 6px;
-    background: rgba(255, 255, 255, 0.08);
+    background: rgba(132, 193, 208, 0.55);
+}
+
+.calendar-dot--bad {
+    background: rgba(255, 117, 117, 0.85);
+}
+
+.calendar-dot--warn {
+    background: rgba(255, 171, 122, 0.82);
 }
 
 .calendar-dot--1 {
-    background: rgba(126, 239, 205, 0.32);
+    background: rgba(116, 226, 183, 0.7);
 }
 
 .calendar-dot--2 {
@@ -444,6 +452,24 @@ button {
     font-size: 11px;
 }
 
+.calendar-link {
+    cursor: pointer;
+}
+
+.calendar-cell--active {
+    transition: transform 140ms ease, filter 140ms ease, stroke 140ms ease, stroke-width 140ms ease;
+    transform-box: fill-box;
+    transform-origin: center;
+}
+
+.calendar-link:hover .calendar-cell--active,
+.calendar-link:focus .calendar-cell--active,
+.calendar-link:focus-visible .calendar-cell--active {
+    filter: brightness(1.08);
+    stroke: rgba(255, 255, 255, 0.8);
+    stroke-width: 1.1;
+}
+
 .line-chart,
 .bar-chart {
     min-height: 17rem;

assets/js/app.js

@@ -366,6 +366,32 @@
             return;
         }
 
+        function calendarColor(entry) {
+            if (!entry) {
+                return "rgba(255, 255, 255, 0.06)";
+            }
+
+            const ratio = Math.max(0, Math.min(1, Number(entry.score) / Math.max(Number(entry.max || 1), 1)));
+
+            if (ratio <= 0.36) {
+                return `rgba(255, 117, 117, ${0.28 + (ratio * 0.8)})`;
+            }
+
+            if (ratio <= 0.52) {
+                return `rgba(255, 171, 122, ${0.28 + (ratio * 0.7)})`;
+            }
+
+            if (ratio <= 0.68) {
+                return `rgba(132, 193, 208, ${0.24 + (ratio * 0.55)})`;
+            }
+
+            if (ratio <= 0.84) {
+                return `rgba(116, 226, 183, ${0.28 + (ratio * 0.6)})`;
+            }
+
+            return `rgba(112, 240, 182, ${0.38 + (ratio * 0.52)})`;
+        }
+
         const map = new Map(items.map(item => [item.date, item]));
         const end = new Date();
         const start = new Date(end);
@@ -386,12 +412,13 @@
             cursor.setDate(cursor.getDate() + 1);
         }
 
-        const width = Math.ceil(days.length / 7) * 17 + 56;
+        const totalWeeks = Math.floor((days.length - 1) / 7) + 1;
         const height = 148;
         const cellSize = 12;
         const cellGap = 5;
         const xOffset = 34;
         const yOffset = 24;
+        const width = xOffset + ((totalWeeks - 1) * (cellSize + cellGap)) + cellSize + 28;
         const monthLabels = [];
         let lastMonth = -1;
 
@@ -400,10 +427,7 @@
             const row = item.weekday === 0 ? 6 : item.weekday - 1;
             const x = xOffset + (week * (cellSize + cellGap));
             const y = yOffset + (row * (cellSize + cellGap));
-            const level = item.entry ? Math.max(0, Math.min(1, Number(item.entry.score) / Math.max(Number(item.entry.max || 1), 1))) : 0;
-            const fill = item.entry
-                ? `rgba(126, 239, 205, ${0.18 + (level * 0.72)})`
-                : "rgba(255, 255, 255, 0.06)";
+            const fill = calendarColor(item.entry);
 
             if (item.day <= 7 && item.month !== lastMonth) {
                 monthLabels.push({
@@ -417,7 +441,16 @@
                 ? `${item.date}: ${formatNumber(Number(item.entry.score))} Punkte · ${item.entry.label}`
                 : `${item.date}: kein Eintrag`;
 
+            if (!item.entry) {
                 return `<rect x="${x}" y="${y}" width="${cellSize}" height="${cellSize}" rx="4" fill="${fill}"><title>${title}</title></rect>`;
+            }
+
+            return `
+                <a class="calendar-link" href="/track?date=${encodeURIComponent(item.date)}" aria-label="${title}">
+                    <rect class="calendar-cell calendar-cell--active" x="${x}" y="${y}" width="${cellSize}" height="${cellSize}" rx="4" fill="${fill}"></rect>
+                    <title>${title}</title>
+                </a>
+            `;
         }).join("");
 
         container.innerHTML = `
@@ -429,14 +462,15 @@
                 ${cells}
             </svg>
             <div class="calendar-legend">
-                <span>weniger</span>
+                <span>schlecht</span>
                 <div class="calendar-scale">
+                    <span class="calendar-dot calendar-dot--bad"></span>
+                    <span class="calendar-dot calendar-dot--warn"></span>
                     <span class="calendar-dot"></span>
                     <span class="calendar-dot calendar-dot--1"></span>
-                    <span class="calendar-dot calendar-dot--2"></span>
                     <span class="calendar-dot calendar-dot--3"></span>
                 </div>
-                <span>mehr</span>
+                <span>gut</span>
             </div>
         `;
     }