From 4354dd6a2eaa8058d951ac99e327d2d82f8f6d7f Mon Sep 17 00:00:00 2001
From: wheat <jacobrclevenger@gmail.com>
Date: Wed, 4 Jan 2023 03:15:24 -0500
Subject: [PATCH] feat: add image preview swipe (#749)

---
 components/modal/ModalMediaPreview.vue        | 55 +++++----------
 .../modal/ModalMediaPreviewCarousel.vue       | 70 +++++++++++++++++++
 styles/global.css                             |  2 +
 3 files changed, 91 insertions(+), 36 deletions(-)
 create mode 100644 components/modal/ModalMediaPreviewCarousel.vue

diff --git a/components/modal/ModalMediaPreview.vue b/components/modal/ModalMediaPreview.vue
index 6efad34e..9f3f8621 100644
--- a/components/modal/ModalMediaPreview.vue
+++ b/components/modal/ModalMediaPreview.vue
@@ -1,32 +1,14 @@
 <script setup lang="ts">
-import { useImageGesture } from '~/composables/gestures'
-
 const emit = defineEmits(['close'])
 
-const img = ref()
+const locked = useScrollLock(document.body)
+
+// Use to avoid strange error when directlying assigning to v-model on ModelMediaPreviewCarousel
+const index = mediaPreviewIndex
 
 const current = computed(() => mediaPreviewList.value[mediaPreviewIndex.value])
-const hasNext = computed(() => mediaPreviewIndex.value < mediaPreviewList.value.length - 1)
-const hasPrev = computed(() => mediaPreviewIndex.value > 0)
-
-useImageGesture(img, {
-  hasNext,
-  hasPrev,
-  onNext() {
-    if (hasNext.value)
-      mediaPreviewIndex.value++
-  },
-  onPrev() {
-    if (hasPrev.value)
-      mediaPreviewIndex.value--
-  },
-})
-
-// stop global zooming
-useEventListener('wheel', (evt) => {
-  if (evt.ctrlKey && (evt.deltaY < 0 || evt.deltaY > 0))
-    evt.preventDefault()
-}, { passive: false })
+const hasNext = computed(() => index.value < mediaPreviewList.value.length - 1)
+const hasPrev = computed(() => index.value > 0)
 
 const keys = useMagicKeys()
 
@@ -35,12 +17,12 @@ whenever(keys.arrowRight, next)
 
 function next() {
   if (hasNext.value)
-    mediaPreviewIndex.value++
+    index.value++
 }
 
 function prev() {
   if (hasPrev.value)
-    mediaPreviewIndex.value--
+    index.value--
 }
 
 function onClick(e: MouseEvent) {
@@ -49,30 +31,31 @@ function onClick(e: MouseEvent) {
   if (!el)
     emit('close')
 }
+
+onMounted(() => locked.value = true)
+onUnmounted(() => locked.value = false)
 </script>
 
 <template>
-  <div relative h-full w-full flex pt-12 @click="onClick">
+  <div relative h-full w-full flex pt-12 w-100vh @click="onClick">
     <button
       v-if="hasNext" pointer-events-auto btn-action-icon bg="black/20" :aria-label="$t('action.previous')"
-      hover:bg="black/40" dark:bg="white/30" dark:hover:bg="white/20" absolute top="1/2" right-1
+      hover:bg="black/40" dark:bg="white/30" dark:hover:bg="white/20" absolute top="1/2" right-1 z5
       :title="$t('action.next')" @click="next"
     >
       <div i-ri:arrow-right-s-line text-white />
     </button>
     <button
       v-if="hasPrev" pointer-events-auto btn-action-icon bg="black/20" aria-label="action.next"
-      hover:bg="black/40" dark:bg="white/30" dark:hover:bg="white/20" absolute top="1/2" left-1
+      hover:bg="black/40" dark:bg="white/30" dark:hover:bg="white/20" absolute top="1/2" left-1 z5
       :title="$t('action.prev')" @click="prev"
     >
       <div i-ri:arrow-left-s-line text-white />
     </button>
-    <img
-      ref="img"
-      :src="current.url || current.previewUrl"
-      :alt="current.description || ''"
-      max-h-full max-w-full ma
-    >
+
+    <div flex flex-row items-center mxa>
+      <ModalMediaPreviewCarousel v-model="index" :media="mediaPreviewList" @close="emit('close')" />
+    </div>
 
     <div absolute top-0 w-full flex justify-between>
       <button
@@ -83,7 +66,7 @@ function onClick(e: MouseEvent) {
       </button>
       <div bg="black/30" dark:bg="white/10" ms-4 my-auto text-white rounded-full flex="~ center" overflow-hidden>
         <div v-if="mediaPreviewList.length > 1" p="y-1 x-2" rounded-r-0 shrink-0>
-          {{ mediaPreviewIndex + 1 }} / {{ mediaPreviewList.length }}
+          {{ index + 1 }} / {{ mediaPreviewList.length }}
         </div>
         <p
           v-if="current.description" bg="dark/30" dark:bg="white/10" p="y-1 x-2" rounded-ie-full line-clamp-1
diff --git a/components/modal/ModalMediaPreviewCarousel.vue b/components/modal/ModalMediaPreviewCarousel.vue
new file mode 100644
index 00000000..edad636c
--- /dev/null
+++ b/components/modal/ModalMediaPreviewCarousel.vue
@@ -0,0 +1,70 @@
+<script setup lang="ts">
+import { SwipeDirection } from '@vueuse/core'
+import { useReducedMotion } from '@vueuse/motion'
+import type { Attachment } from 'masto'
+
+const props = withDefaults(defineProps<{ media: Attachment[]; threshold?: number; modelValue: number }>(), {
+  media: [] as any,
+  threshold: 20,
+  modelValue: 0,
+})
+
+const emit = defineEmits<{
+  (e: 'update:modelValue', v: boolean): void
+  (event: 'close'): void
+}>()
+
+const target = ref()
+const index = useVModel(props, 'modelValue', emit)
+
+const animateTimeout = useTimeout(10)
+const reduceMotion = useReducedMotion()
+
+const canAnimate = computed(() => !reduceMotion.value && animateTimeout.value)
+
+const { width, height } = useElementSize(target)
+const { isSwiping, lengthX, lengthY, direction } = useSwipe(target, {
+  threshold: 5,
+  passive: false,
+  onSwipeEnd(e, direction) {
+    // eslint-disable-next-line @typescript-eslint/no-use-before-define
+    if (direction === SwipeDirection.RIGHT && Math.abs(distanceX.value) > props.threshold)
+      index.value = Math.max(0, index.value - 1)
+
+    // eslint-disable-next-line @typescript-eslint/no-use-before-define
+    if (direction === SwipeDirection.LEFT && Math.abs(distanceX.value) > props.threshold)
+      index.value = Math.min(props.media.length - 1, index.value + 1)
+
+    // eslint-disable-next-line @typescript-eslint/no-use-before-define
+    if (direction === SwipeDirection.UP && Math.abs(distanceY.value) > props.threshold)
+      emit('close')
+  },
+})
+
+const distanceX = computed(() => {
+  if (width.value === 0)
+    return 0
+
+  if (!isSwiping.value || (direction.value !== SwipeDirection.LEFT && direction.value !== SwipeDirection.RIGHT))
+    return index.value * 100 * -1
+
+  return (lengthX.value / width.value) * 100 * -1 + (index.value * 100) * -1
+})
+
+const distanceY = computed(() => {
+  if (height.value === 0 || !isSwiping.value || direction.value !== SwipeDirection.UP)
+    return 0
+
+  return (lengthY.value / height.value) * 100 * -1
+})
+</script>
+
+<template>
+  <div ref="target" flex flex-row max-h-full max-w-full overflow-hidden>
+    <div flex :style="{ transform: `translateX(${distanceX}%) translateY(${distanceY}%)`, transition: isSwiping ? 'none' : canAnimate ? 'all 0.5s ease' : 'none' }">
+      <div v-for="item in media" :key="item.id" p4 select-none w-full flex-shrink-0 flex flex-col place-items-center>
+        <img max-h-full max-w-full :draggable="false" select-none :src="item.url || item.previewUrl" :alt="item.description || ''">
+      </div>
+    </div>
+  </div>
+</template>
diff --git a/styles/global.css b/styles/global.css
index b88e47ee..6f28e28b 100644
--- a/styles/global.css
+++ b/styles/global.css
@@ -1,5 +1,7 @@
 html {
   font-size: var(--font-size, 15px);
+  width: 100%;
+  width: 100vw;
 }
 
 @font-face {