fix bug

src/utils/useDraggableFloatingButton.ts

@@ -1,24 +1,54 @@
 import { computed, onMounted, onUnmounted, ref } from 'vue'
 
 const DRAG_THRESHOLD = 6
+const POSITION_VERSION = 1
 
 type FabPosition = { x: number; y: number }
 
+type SavedFabOffset = {
+  version: number
+  dx: number
+  dy: number
+}
+
 type DraggableFloatingOptions = {
   width?: number
   height?: number
-  defaultBottomOffset?: number
+  /** فاصله از پایینِ نوار منو + montzar (px) — مثل تصویر */
+  defaultBottomGap?: number
   defaultRightOffset?: number
 }
 
+function readBottomChromeHeight(): number {
+  const styles = getComputedStyle(document.documentElement)
+  const direct = parseFloat(styles.getPropertyValue('--app-bottom-chrome-height'))
+  if (!Number.isNaN(direct) && direct > 0) {
+    return direct
+  }
+
+  const nav = parseFloat(styles.getPropertyValue('--app-nav-height')) || 80
+  const creditOffset = parseFloat(styles.getPropertyValue('--app-credit-footer-offset'))
+  if (!Number.isNaN(creditOffset) && creditOffset > 0) {
+    return nav + creditOffset
+  }
+
+  const probe = document.createElement('div')
+  probe.style.cssText = 'position:fixed;visibility:hidden;pointer-events:none;height:var(--app-bottom-chrome-height)'
+  document.body.appendChild(probe)
+  const measured = probe.getBoundingClientRect().height
+  document.body.removeChild(probe)
+
+  return measured > 0 ? measured : nav + 28
+}
+
 export function useDraggableFloatingButton(
   storageKey: string,
   options: DraggableFloatingOptions = {}
 ) {
   const width = options.width ?? 96
   const height = options.height ?? 44
-  const defaultBottomOffset = options.defaultBottomOffset ?? 120
-  const defaultRightOffset = options.defaultRightOffset ?? 20
+  const defaultBottomGap = options.defaultBottomGap ?? 12
+  const defaultRightOffset = options.defaultRightOffset ?? 16
 
   const pos = ref<FabPosition>({ x: 0, y: 0 })
   const dragging = ref(false)
@@ -44,26 +74,40 @@ export function useDraggableFloatingButton(
   function getHorizontalOffset() {
     const vw = window.innerWidth
     const contentWidth = getViewportWidth()
+
     return Math.max(0, (vw - contentWidth) / 2)
   }
 
-  function resetToDefault() {
+  function getDefaultPosition(): FabPosition {
     const vh = window.innerHeight
     const offsetX = getHorizontalOffset()
     const contentWidth = getViewportWidth()
+    const bottomChrome = readBottomChromeHeight()
 
-    pos.value = {
+    return {
       x: offsetX + contentWidth - width - defaultRightOffset,
-      y: vh - defaultBottomOffset - height
+      y: vh - bottomChrome - defaultBottomGap - height
     }
   }
 
+  function applySavedOffset(dx: number, dy: number) {
+    const base = getDefaultPosition()
+    pos.value = {
+      x: base.x + dx,
+      y: base.y + dy
+    }
+    clampToViewport()
+  }
+
   function clampToViewport() {
-    const vw = window.innerWidth
     const vh = window.innerHeight
+    const offsetX = getHorizontalOffset()
+    const contentWidth = getViewportWidth()
+    const minX = offsetX
+    const maxX = offsetX + contentWidth - width
 
     pos.value = {
-      x: Math.max(0, Math.min(vw - width, pos.value.x)),
+      x: Math.max(minX, Math.min(maxX, pos.value.x)),
       y: Math.max(0, Math.min(vh - height, pos.value.y))
     }
   }
@@ -72,25 +116,56 @@ export function useDraggableFloatingButton(
     try {
       const raw = localStorage.getItem(storageKey)
       if (!raw) return false
-      const parsed = JSON.parse(raw) as FabPosition
-      if (typeof parsed?.x === 'number' && typeof parsed?.y === 'number') {
-        pos.value = parsed
-        clampToViewport()
+
+      const parsed = JSON.parse(raw) as SavedFabOffset
+      if (
+        parsed?.version === POSITION_VERSION
+        && typeof parsed.dx === 'number'
+        && typeof parsed.dy === 'number'
+      ) {
+        applySavedOffset(parsed.dx, parsed.dy)
         return true
       }
     } catch {
       // ignore
     }
+
     return false
   }
 
   function savePosition() {
-    localStorage.setItem(storageKey, JSON.stringify(pos.value))
+    const base = getDefaultPosition()
+    const payload: SavedFabOffset = {
+      version: POSITION_VERSION,
+      dx: pos.value.x - base.x,
+      dy: pos.value.y - base.y
+    }
+    localStorage.setItem(storageKey, JSON.stringify(payload))
+  }
+
+  function resetToDefault() {
+    pos.value = getDefaultPosition()
   }
 
   function handleResize() {
-    clampToViewport()
-    savePosition()
+    try {
+      const raw = localStorage.getItem(storageKey)
+      if (raw) {
+        const parsed = JSON.parse(raw) as SavedFabOffset
+        if (
+          parsed?.version === POSITION_VERSION
+          && typeof parsed.dx === 'number'
+          && typeof parsed.dy === 'number'
+        ) {
+          applySavedOffset(parsed.dx, parsed.dy)
+          return
+        }
+      }
+    } catch {
+      // ignore
+    }
+
+    resetToDefault()
   }
 
   function handlePointerDown(event: PointerEvent) {