<script setup lang="ts">
import { computed, onMounted, onUnmounted, ref, watch } from 'vue'
import { QAInfo, QuestionDisplayAlign, Setting_QuestionDisplay } from '@/api/api-models'
import { useDebounceFn, useScroll, useStorage } from '@vueuse/core'

const props = defineProps<{
  question: QAInfo | undefined
  setting: Setting_QuestionDisplay

  showGreenBorder?: boolean
  css?: string
}>()
defineExpose({ setScroll, setScrollTop })
const emit = defineEmits<{ scroll: [value: { clientHeight: number, scrollHeight: number, scrollTop: number }] }>()

let styleElement: HTMLStyleElement
const cssDebounce = useDebounceFn(() => {
  if (styleElement) {
    styleElement.textContent = props.css ?? ''
    console.log('已更新CSS')
  }
}, 1000)
watch(() => props.css, cssDebounce)

const contentRef = ref()
const { x, y, isScrolling, arrivedState, directions } = useScroll(contentRef)


const align = computed(() => {
  switch (props.setting.align) {
    case QuestionDisplayAlign.Left:
      return 'left'
    case QuestionDisplayAlign.Right:
      return 'right'
    case QuestionDisplayAlign.Center:
      return 'center'
  }
  return 'left'
})
function setScrollTop(top: number) {
  contentRef.value?.scrollTo({
    top: top,
    behavior: 'smooth',
  })
}
function setScroll(value: { clientHeight: number, scrollHeight: number, scrollTop: number }) {
  if (contentRef.value.clientHeight == contentRef.value.scrollHeight) {
    setScrollTop(value.scrollTop)
  } else {
    const scrollRatio1 = value.scrollTop / (value.scrollHeight - value.clientHeight);
    const scrollTop = scrollRatio1 * (contentRef.value.scrollHeight - contentRef.value.clientHeight);
    setScrollTop(scrollTop)
  }
}
function scrollCallback(e: Event) {
  emit('scroll', {
    clientHeight: contentRef.value?.clientHeight ?? 0,
    scrollHeight: contentRef.value?.scrollHeight ?? 0,
    scrollTop: contentRef.value?.scrollTop ?? 0
  })
}

onMounted(() => {
  // 创建<style>元素并添加到<head>中
  styleElement = document.createElement('style')
  // 可能需要对 userStyleString 做安全处理以避免XSS攻击
  styleElement.textContent = props.css ?? ''
  document.head.appendChild(styleElement)

  contentRef.value?.addEventListener('scroll', scrollCallback)
})
onUnmounted(() => {
  if (styleElement && styleElement.parentNode) {
    styleElement.parentNode.removeChild(styleElement)
  }
  contentRef.value?.removeEventListener('scroll', scrollCallback)
})
</script>

<template>
  <div
    class="question-display-root"
    :style="{
      backgroundColor: '#' + setting.borderColor,
      borderColor: setting.borderColor ? '#' + setting.borderColor : undefined,
      borderWidth: setting.borderWidth ? setting.borderWidth + 'px' : undefined,
      borderTopWidth: setting.showUserName && question ? 0 : setting.borderWidth,
    }"
    :display="question ? 1 : 0"
  >
    <Transition
      name="scale"
      mode="out-in"
    >
      <div
        v-if="setting.showUserName && question"
        class="question-display-user-name"
        :style="{
          color: '#' + setting.nameFontColor,
          fontSize: setting.nameFontSize + 'px',
          fontWeight: setting.nameFontWeight ? setting.nameFontWeight : undefined,
          fontFamily: setting.nameFont,
        }"
      >
        {{ question?.sender?.name ?? '匿名用户' }}
      </div>
    </Transition>
    <div
      ref="contentRef"
      class="question-display-content"
      :style="{
        color: '#' + setting.fontColor,
        backgroundColor: '#' + setting.backgroundColor,
        fontSize: setting.fontSize + 'px',
        fontWeight: setting.fontWeight ? setting.fontWeight : undefined,
        textAlign: align,
        fontFamily: setting.font,
      }"
      :is-empty="question ? 0 : 1"
      @scroll="scrollCallback"
    >
      <Transition
        name="fade"
        mode="out-in"
      >
        <template v-if="question">
          <div>
            <div class="question-display-text">
              {{ question?.question.message }}
            </div>
            <img
              v-if="setting.showImage && question?.question.image"
              class="question-display-image"
              :src="question?.question.image"
            >
          </div>
        </template>
        <div
          v-else
          class="question-display-loading loading"
          :style="{ color: '#' + setting.fontColor }"
        >
          <div :style="{ color: '#' + setting.fontColor }" />
          <div />
          <div />
          <div />
        </div>
      </Transition>
    </div>
  </div>
</template>

<style scoped>
.question-display-root {
  height: 100%;
  width: 100%;
  border-radius: 16px;
  border: 2 solid rgb(255, 255, 255);
  display: flex;
  flex-direction: column;
  border-style: solid;
  box-sizing: border-box;
  transition: all 0.3s ease;
}

.question-display-content {
  border-radius: 10px;
  display: flex;
  flex-direction: column;
  height: 100%;
  justify-content: space-evenly;
  padding: 24px;
  overflow: auto;
}

.question-display-user-name {
  text-align: center;
  margin: 5px;
  height: 32px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.question-display-text {
  min-height: 50px;
  white-space: pre-wrap;
}

.question-display-image {
  max-width: 40%;
  max-height: 40%;
  margin: 0 auto;
}

::-webkit-scrollbar {
  width: 10px;

  height: 10px;
}

::-webkit-scrollbar-thumb {
  background: hsla(0, 0%, 51%, 0.377);

  -webkit-box-shadow: none;

  border-radius: 10px;

  -webkit-box-shadow: none;
}

::-webkit-scrollbar-track {
  border-radius: 10px;

  background: #cccccc4b;

  -webkit-box-shadow: none;

  -webkit-box-shadow: none;
}
</style>

<style scoped>
.loading,
.loading>div {
  position: relative;
  box-sizing: border-box;
}

.loading {
  display: block;
  margin: 0 auto;
  font-size: 0;
}

.loading.la-dark {
  color: #333;
}

.loading>div {
  display: inline-block;
  float: none;
  background-color: currentColor;
  border: 0 solid currentColor;
}

.loading {
  width: 40px;
  height: 10px;
}

.loading>div {
  width: 10px;
  height: 10px;
  border-radius: 100%;
}

.loading>div:first-child {
  transform: translateX(0%);
  animation: ball-newton-cradle-left 1.5s 0s ease-out infinite;
}

.loading>div:last-child {
  transform: translateX(0%);
  animation: ball-newton-cradle-right 1.5s 0s ease-out infinite;
}

.loading.la-sm {
  width: 20px;
  height: 4px;
}

.loading.la-sm>div {
  width: 4px;
  height: 4px;
}

.loading.la-2x {
  width: 80px;
  height: 20px;
}

.loading.la-2x>div {
  width: 20px;
  height: 20px;
}

.loading.la-3x {
  width: 120px;
  height: 30px;
}

.loading.la-3x>div {
  width: 30px;
  height: 30px;
}

@keyframes ball-newton-cradle-left {
  25% {
    transform: translateX(-200%);
    animation-timing-function: ease-in;
  }

  50% {
    transform: translateX(0%);
  }
}

@keyframes ball-newton-cradle-right {
  50% {
    transform: translateX(0%);
  }

  75% {
    transform: translateX(200%);
    animation-timing-function: ease-in;
  }

  100% {
    transform: translateX(0%);
  }
}

.loading>div:first-child {
  animation: ball-newton-cradle-left 1.5s 0s ease-in-out infinite;
}

.loading>div:last-child {
  animation: ball-newton-cradle-right 1.5s 0s ease-in-out infinite;
}
</style>
