<template>
  <!-- <van-nav-bar v-if="!isback" :title="name" :border="isBorder" left-arrow @click-left="onClickLeft" :style="barStyle" />
  <van-nav-bar v-else :title="name" /> -->
  <van-nav-bar v-if="!isback" :title="name" :border="isBorder" left-arrow @click-left="onClickLeft" :style="barStyle">
    <!-- 右侧语言切换 -->
    <template #right>
      <div class="nav-language">
        <van-button round size="small" class="lang-trigger" @click="showPopover = true">
          <div class="current-lang">
            <img :src="currentLang.flag" class="current-flag" />
            <span class="lang-code">{{ currentLang.code.toUpperCase() }}</span>
          </div>
        </van-button>

        <van-popover v-model:show="showPopover" :offset="[0, 8]" placement="bottom-end" class="lang-popover">
          <van-cell-group>
            <van-cell v-for="lang in languages" :key="lang.code"
              :class="['lang-item', { active: lang.code === currentLang.code }]" @click="handleChangeLanguage(lang)">
              <template #icon>
                <img :src="lang.flag" class="flag" :alt="lang.code">
              </template>
              <div class="lang-content">
                <span class="lang-label">{{ lang.label }}</span>
                <span class="lang-code">{{ lang.code.toUpperCase() }}</span>
              </div>
            </van-cell>
          </van-cell-group>
        </van-popover>
      </div>
    </template>
  </van-nav-bar>
  <van-nav-bar v-else :title="name">
    <!-- 右侧语言切换 -->
    <template #right>
      <div class="nav-language">
        <van-button round size="small" class="lang-trigger" @click="showPopover = true">
          <div class="current-lang">
            <img :src="currentLang.flag" class="current-flag" />
            <span class="lang-code">{{ currentLang.code.toUpperCase() }}</span>
          </div>
        </van-button>

        <van-popover v-model:show="showPopover" :offset="[0, 8]" placement="bottom-end" class="lang-popover">
          <van-cell-group>
            <van-cell v-for="lang in languages" :key="lang.code"
              :class="['lang-item', { active: lang.code === currentLang.code }]" @click="handleChangeLanguage(lang)">
              <template #icon>
                <img :src="lang.flag" class="flag" :alt="lang.code">
              </template>
              <div class="lang-content">
                <span class="lang-label">{{ lang.label }}</span>
                <span class="lang-code">{{ lang.code.toUpperCase() }}</span>
              </div>
            </van-cell>
          </van-cell-group>
        </van-popover>
      </div>
    </template>
  </van-nav-bar>
</template>

<script>
import { ref } from 'vue'
import { useRouter } from 'vue-router'
import { useI18n } from 'vue-i18n';
import { Locale } from 'vant';
// 引入英文语言包
import enUS from "vant/es/locale/lang/en-US";
// 引入简体中文语言包
import zhCN from "vant/es/locale/lang/zh-CN";
import jaJP from "vant/es/locale/lang/ja-JP";
// 引入俄语语言包
import ruRU from "vant/es/locale/lang/ru-RU";
// 引入法语语言包
import frFR from "vant/es/locale/lang/fr-FR";
// 引入西班牙语语言包
import esES from "vant/es/locale/lang/es-ES";
// 引入葡萄牙语语言包
import ptBR from "vant/es/locale/lang/pt-BR";
// 引入乌克兰语语言包
import ukUA from "vant/es/locale/lang/uk-UA";
export default {
  props: {
    name: {
      type: String,
      default: ''
    },
    back: {
      type: String,
      default: ''
    },
    noback: {
      type: Boolean,
      default: false
    },
    // 是否固定在顶部
    isFixed: {
      type: Boolean,
      default: true
    },
    // 锁定要跳转的页面路径
    targetPath: {
      type: String,
      default: ''
    },
    // 是否显示下边框
    isBorder: {
      type: Boolean,
      default: true
    },
    barStyle: {
      type: Object,
      default: () => ({})
    }
  },
  emits: ['callback'],
  setup(props, ctx) {
    const isback = ref(props.noback)
    const router = useRouter()
    const goBack = () => {
      if (props.targetPath) {
        router.replace({ path: props.targetPath })
      } else if (!props.back) {
        router.go(-1)
      } else {
        router.push({ path: props.back })
      }
      ctx.emit('callback')
    }

    const { locale } = useI18n();
    // 可用语言列表
    const languages = ref([
      { code: 'zh', label: '简体中文', vant: zhCN, flag: 'https://flagcdn.com/cn.svg' },
      { code: 'en', label: 'English', vant: enUS, flag: 'https://flagcdn.com/us.svg' },
      { code: 'ja', label: '日本語', vant: jaJP, flag: 'https://flagcdn.com/jp.svg' },
      { code: 'ru', label: 'Русский', vant: ruRU, flag: 'https://flagcdn.com/ru.svg' },
      { code: 'fr', label: 'Français', vant: frFR, flag: 'https://flagcdn.com/fr.svg' },
      { code: 'es', label: 'Español', vant: esES, flag: 'https://flagcdn.com/es.svg' },
      { code: 'pt', label: 'Português', vant: ptBR, flag: 'https://flagcdn.com/pt.svg' },
      { code: 'uk', label: 'Українська', vant: ukUA, flag: 'https://flagcdn.com/ua.svg' }
    ]);

    // 当前语言
    const currentLang = ref(languages.value.find(l => l.code === locale.value) || languages.value[0]);
    const showPopover = ref(false);

    // 切换语言
    const handleChangeLanguage = async (lang) => {
      currentLang.value = lang;
      locale.value = lang.code;
      // 1. 切换应用语言
      locale.value = lang.code

      // 2. 切换 Vant 语言
      Locale.use(lang.code, lang.vant)
      showPopover.value = false;

      // 3. (可选) 持久化存储
      localStorage.setItem('curLang', lang.code)
    };

    const onClickLeft = () => history.back();
    return {
      goBack,
      isback,
      onClickLeft,
      handleChangeLanguage,
      showPopover,
      languages,
      currentLang
    }
  }
}
</script>

<style lang="less" scoped>
@import '../common/style/mixin';

.simple-header {
  // position: fixed;
  top: 0;
  left: 0;
  z-index: 999;
  .fj();
  .wh(100%, 44px);
  line-height: 44px;
  padding: 0 10px;
  .boxSizing();
  color: #404d74;
  background: #fff;

  .simple-header-name {
    white-space: nowrap;
    font-size: 15px;
    font-weight: 600;
  }
}


.block {
  width: 100%;
  height: 44px;
}

.moreIcon {
  visibility: hidden;
}

.current-lang {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 2px;
}

.current-flag {
  width: 20px;
  height: 15px;
  border-radius: 2px;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.lang-code {
  font-size: 14px;
  font-weight: 500;
  color: #333;
  margin-top: 1px;
}

.nav-language {
  margin-right: -8px;
}

.lang-trigger {
  padding: 4px 8px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid #eee;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  border: 1px solid #eee;
  /* 边框颜色 */
  color: #4d6add;
  /* 文字颜色 */

  &:hover {
    border-color: #3a52b3;
    color: #3a52b3;
    background: rgba(77, 106, 221, 0.05);
  }
}


/* 点击状态 */
.lang-trigger:active {
  border-color: #2e4096;
  color: #2e4096;
  background: rgba(77, 106, 221, 0.1);
}

.globe-icon {
  font-size: 16px;
  color: #666;
  margin-right: 6px;
}

.lang-text {
  font-size: 14px;
  font-weight: 500;
  color: #333;
}

.lang-popover {
  --van-popover-arrow-size: 8px;
}

.lang-item {
  padding: 10px 16px;

  &.active {
    background: #f5f8ff;

    .lang-label {
      color: var(--van-blue);
    }
  }
}

/* 调整后的样式 */
.van-cell {
  --cell-vertical-padding: 12px; /* 统一垂直间距 */
  display: flex;
  align-items: center; /* 主轴线居中 */
}

.flag {
  width: 22px;
  height: 16px;
  border-radius: 2px;
  margin-right: 12px;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
  vertical-align: middle; /* 行内元素垂直对齐 */
  position: relative;
  top: -1px; /* 微调视觉平衡 */
}

.lang-content {
  display: flex;
  align-items: center;
  gap: 8px;
}

.lang-label {
  line-height: 24px;
  font-size: 14px;
  color: #333;
  gap: 8px;
}

.lang-code {
  font-size: 12px;
  color: #4d6add;
  font-weight: 600;
  /* 增加字重提升可读性 */
  letter-spacing: 0.5px;
}

/* 国旗悬停动画 */
.lang-trigger:hover .current-flag {
  filter: brightness(0.9);
}
</style>
