feat: reorder criteria and profiles by dragging

Add a drag handle to each criterion and profile row, backed by a
pointer-based composable that works with mouse and touch. Reordering
criteria changes the chart spoke order; reordering profiles changes
draw/legend order. Scores are keyed by id, so they follow their row.

src/components/CriteriaEditor.vue

@@ -1,11 +1,24 @@
 <script setup lang="ts">
+import { ref } from "vue"
 import type { Radar } from "../types"
 import { MIN_CRITERIA, MAX_CRITERIA } from "../types"
 import { useRadars } from "../storage"
+import { useDragReorder } from "../utils/reorder"
 
 const props = defineProps<{ radar: Radar }>()
 const { update, blankCriterion } = useRadars()
 
+const listEl = ref<HTMLElement | null>(null)
+const { draggingId, startDrag } = useDragReorder({
+  container: listEl,
+  getIds: () => props.radar.criteria.map((c) => c.id),
+  reorder: (from, to) =>
+    update(props.radar.id, (r) => {
+      const [moved] = r.criteria.splice(from, 1)
+      r.criteria.splice(to, 0, moved)
+    }),
+})
+
 function addCriterion(): void {
   update(props.radar.id, (r) => {
     if (r.criteria.length >= MAX_CRITERIA) return
@@ -39,8 +52,22 @@ function renameCriterion(criterionId: string, name: string): void {
     <p class="text-xs text-base-content/60 mb-3">
       Phrase each Criterion so higher is better (e.g. <em>Affordability</em>, not <em>Price</em>).
     </p>
-    <ul class="flex flex-col gap-2">
+    <ul ref="listEl" class="flex flex-col gap-2">
-      <li v-for="c in radar.criteria" :key="c.id" class="flex items-center gap-2">
+      <li
+        v-for="c in radar.criteria"
+        :key="c.id"
+        data-reorder-item
+        class="flex items-center gap-2 rounded-lg transition-opacity"
+        :class="draggingId === c.id ? 'opacity-50' : ''"
+      >
+        <span
+          class="cursor-grab touch-none select-none px-1 text-base-content/40 hover:text-base-content/70 active:cursor-grabbing"
+          aria-label="Drag to reorder"
+          title="Drag to reorder"
+          @pointerdown="startDrag($event, c.id)"
+        >
+          ⠿
+        </span>
         <input
           type="text"
           class="input input-bordered input-sm flex-1"

src/components/ProfilesEditor.vue

@@ -1,11 +1,24 @@
 <script setup lang="ts">
+import { ref } from "vue"
 import type { Radar } from "../types"
 import { MIN_PROFILES, MAX_PROFILES, PROFILE_PALETTE } from "../types"
 import { useRadars } from "../storage"
+import { useDragReorder } from "../utils/reorder"
 
 const props = defineProps<{ radar: Radar }>()
 const { update, blankProfile } = useRadars()
 
+const listEl = ref<HTMLElement | null>(null)
+const { draggingId, startDrag } = useDragReorder({
+  container: listEl,
+  getIds: () => props.radar.profiles.map((p) => p.id),
+  reorder: (from, to) =>
+    update(props.radar.id, (r) => {
+      const [moved] = r.profiles.splice(from, 1)
+      r.profiles.splice(to, 0, moved)
+    }),
+})
+
 function addProfile(): void {
   update(props.radar.id, (r) => {
     if (r.profiles.length >= MAX_PROFILES) return
@@ -47,13 +60,23 @@ function setColor(profileId: string, color: string): void {
       Each Profile is one shape on the radar (e.g. <em>Us today</em>, <em>Us 2027</em>,
       <em>Acme Corp</em>).
     </p>
-    <ul class="flex flex-col gap-3">
+    <ul ref="listEl" class="flex flex-col gap-3">
       <li
         v-for="p in radar.profiles"
         :key="p.id"
-        class="flex flex-col gap-2 p-3 rounded-lg border border-base-300 bg-base-100"
+        data-reorder-item
+        class="flex flex-col gap-2 p-3 rounded-lg border border-base-300 bg-base-100 transition-opacity"
+        :class="draggingId === p.id ? 'opacity-50' : ''"
       >
         <div class="flex items-center gap-2">
+          <span
+            class="cursor-grab touch-none select-none text-base-content/40 hover:text-base-content/70 active:cursor-grabbing"
+            aria-label="Drag to reorder"
+            title="Drag to reorder"
+            @pointerdown="startDrag($event, p.id)"
+          >
+            ⠿
+          </span>
           <span
             class="inline-block w-4 h-4 rounded"
             :style="{ background: p.color }"

src/utils/reorder.ts

@@ -0,0 +1,62 @@
+import { onScopeDispose, ref, type Ref } from "vue"
+
+/**
+ * Pointer-based drag-to-reorder for a vertical list. Works with mouse and touch
+ * (via Pointer Events). The list must render its items in array order, each item
+ * element carrying a `data-reorder-item` attribute, inside `container`.
+ *
+ * Reordering is live: as the pointer crosses a neighbour's midpoint, `reorder`
+ * is called to move the dragged item, and the list re-renders in the new order.
+ */
+export function useDragReorder(opts: {
+  container: Ref<HTMLElement | null>
+  getIds: () => string[]
+  reorder: (from: number, to: number) => void
+}) {
+  const draggingId = ref<string | null>(null)
+
+  // Insertion index (in current DOM order) for the given pointer Y.
+  function indexFromPoint(clientY: number): number {
+    const el = opts.container.value
+    if (!el) return -1
+    const items = Array.from(el.querySelectorAll<HTMLElement>("[data-reorder-item]"))
+    for (let i = 0; i < items.length; i++) {
+      const r = items[i].getBoundingClientRect()
+      if (clientY < r.top + r.height / 2) return i
+    }
+    return items.length
+  }
+
+  function onMove(e: PointerEvent): void {
+    const id = draggingId.value
+    if (id == null) return
+    const ids = opts.getIds()
+    const from = ids.indexOf(id)
+    if (from === -1) return
+    let to = indexFromPoint(e.clientY)
+    if (to === -1) return
+    // The dragged item still occupies its slot, so an insertion point below it
+    // shifts down by one once it's removed.
+    if (from < to) to--
+    if (to !== from) opts.reorder(from, to)
+  }
+
+  function stop(): void {
+    draggingId.value = null
+    window.removeEventListener("pointermove", onMove)
+    window.removeEventListener("pointerup", stop)
+    window.removeEventListener("pointercancel", stop)
+  }
+
+  function startDrag(e: PointerEvent, id: string): void {
+    e.preventDefault()
+    draggingId.value = id
+    window.addEventListener("pointermove", onMove)
+    window.addEventListener("pointerup", stop)
+    window.addEventListener("pointercancel", stop)
+  }
+
+  onScopeDispose(stop)
+
+  return { draggingId, startDrag }
+}