<template>
  <div class="data-square">
    <!-- Header -->
    <header class="header">
      <div class="header-content">
        <div class="header-left" @click="goHome">
          <el-icon><ArrowLeft /></el-icon>
          <span>返回</span>
        </div>
        <div class="header-title">
          <h1>数据集广场</h1>
          <p>发现和分享高质量数据集</p>
        </div>
      </div>
    </header>

    <!-- Main -->
    <main class="main">
      <!-- Filters -->
      <div class="filters">
        <div class="search-box">
          <el-icon class="search-icon"><Search /></el-icon>
          <el-input v-model="searchQuery" placeholder="搜索数据集..." clearable class="search-input" />
        </div>
        <el-select v-model="filterType" placeholder="类型" clearable class="type-select">
          <el-option label="全部类型" value="" />
          <el-option label="问答对" value="qa" />
          <el-option label="多轮对话" value="conversation" />
          <el-option label="指令跟随" value="instruction" />
        </el-select>
      </div>

      <!-- Stats Bar -->
      <div class="stats-bar">
        <span class="stat">
          <strong>{{ datasets.length }}</strong> 个数据集可用
        </span>
      </div>

      <!-- Grid -->
      <div class="dataset-grid" v-loading="loading">
        <div v-if="!loading && datasets.length === 0" class="empty-state">
          <el-icon size="56"><Collection /></el-icon>
          <h3>未找到数据集</h3>
          <p>请尝试调整搜索条件或筛选器</p>
        </div>
        <div
          v-else
          v-for="(dataset, index) in datasets"
          :key="dataset.id"
          class="dataset-card"
          :style="{ '--delay': index * 0.08 + 's' }"
        >
          <div class="card-cover">
            <div class="cover-gradient"></div>
            <div class="cover-pattern"></div>
            <el-icon size="40" class="cover-icon"><Collection /></el-icon>
          </div>
          <div class="card-body">
            <div class="card-header">
              <h3 class="card-title">{{ dataset.name }}</h3>
              <el-tag size="small" effect="dark">{{ dataset.type || '问答' }}</el-tag>
            </div>
            <p class="card-desc">{{ dataset.description }}</p>
            <div class="card-stats">
              <div class="stat-item">
                <el-icon><Document /></el-icon>
                <span>{{ dataset.question_count }} 条</span>
              </div>
              <div class="stat-item">
                <el-icon><User /></el-icon>
                <span>{{ dataset.author }}</span>
              </div>
            </div>
            <div class="card-tags">
              <el-tag v-for="tag in dataset.tags" :key="tag" size="small" effect="plain">{{ tag }}</el-tag>
            </div>
            <div class="card-footer">
              <span class="card-date">{{ formatDate(dataset.created_at) }}</span>
              <div class="card-actions">
                <el-button type="primary" size="small" @click="viewDataset(dataset)">
                  <el-icon><View /></el-icon>
                  查看
                </el-button>
                <el-button size="small" @click="downloadDataset(dataset)">
                  <el-icon><Download /></el-icon>
                  下载
                </el-button>
              </div>
            </div>
          </div>
        </div>
      </div>
    </main>
  </div>
</template>

<script setup>
import { ref, onMounted } from 'vue'
import { useRouter } from 'vue-router'
import { ElMessage } from 'element-plus'

const router = useRouter()
const loading = ref(false)
const searchQuery = ref('')
const filterType = ref('')
const datasets = ref([])

const goHome = () => router.push('/')

const fetchDatasets = async () => {
  loading.value = true
  setTimeout(() => {
    datasets.value = [
      { id: '1', name: '通用知识问答', description: '涵盖科学、历史和地理的综合问答数据集', question_count: 10000, author: '数据集团队', created_at: '2024-01-15', tags: ['知识', '通用'], type: '问答' },
      { id: '2', name: '代码理解', description: '多语言代码理解和解释数据集', question_count: 5000, author: 'Code AI', created_at: '2024-02-20', tags: ['代码', '编程'], type: '指令' },
      { id: '3', name: '数学推理', description: '包含详细步骤解答的数学问题集', question_count: 8000, author: '数学实验室', created_at: '2024-03-10', tags: ['数学', '推理'], type: '问答' },
      { id: '4', name: '医学知识问答', description: '专业医学领域问答数据集', question_count: 3500, author: '医学 AI', created_at: '2024-04-05', tags: ['医学', '专业'], type: '问答' }
    ]
    loading.value = false
  }, 500)
}

const viewDataset = (d) => ElMessage.info('查看中: ' + d.name)
const downloadDataset = (d) => ElMessage.success('下载中: ' + d.name)
const formatDate = (d) => d ? d.split('-').slice(1).join('/') : ''

onMounted(() => fetchDatasets())
</script>

<style scoped>
.data-square { min-height: 100vh; }

/* Header */
.header {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-subtle);
  padding: 20px 24px;
}

.header-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 20px;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  padding: 8px 14px;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.header-left:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.header-title h1 {
  font-size: 22px;
  font-weight: 600;
  margin-bottom: 4px;
}

.header-title p {
  font-size: 14px;
  color: var(--text-tertiary);
}

/* Main */
.main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 28px 24px;
}

/* Filters */
.filters {
  display: flex;
  gap: 12px;
  margin-bottom: 16px;
}

.search-box {
  position: relative;
  flex: 1;
  max-width: 400px;
}

.search-icon {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  z-index: 1;
}

.search-input {
  width: 100%;
}

.search-input :deep(.el-input__wrapper) {
  padding-left: 40px;
}

.type-select {
  width: 160px;
}

/* Stats Bar */
.stats-bar {
  margin-bottom: 24px;
  font-size: 14px;
  color: var(--text-tertiary);
}

.stats-bar strong {
  color: var(--text-primary);
}

/* Dataset Grid */
.dataset-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 20px;
}

.dataset-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-base);
  animation: cardIn 0.5s ease backwards;
  animation-delay: var(--delay);
}

@keyframes cardIn {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.95);
  }
}

.dataset-card:hover {
  border-color: var(--accent-primary);
  transform: translateY(-4px);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.card-cover {
  height: 120px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.cover-gradient {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #22d3ee 0%, #7c3aed 50%, #06b6d4 100%);
  opacity: 0.85;
}

.cover-pattern {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle at 25% 25%, rgba(255,255,255,0.1) 1px, transparent 1px);
  background-size: 20px 20px;
}

.cover-icon {
  position: relative;
  z-index: 1;
  color: white;
  filter: drop-shadow(0 2px 8px rgba(0,0,0,0.3));
}

.card-body {
  padding: 20px;
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 10px;
}

.card-title {
  font-size: 16px;
  font-weight: 600;
  flex: 1;
}

.card-desc {
  font-size: 13px;
  color: var(--text-tertiary);
  line-height: 1.5;
  margin-bottom: 14px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card-stats {
  display: flex;
  gap: 20px;
  margin-bottom: 14px;
}

.stat-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--text-muted);
}

.card-tags {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 14px;
  border-top: 1px solid var(--border-subtle);
}

.card-date {
  font-size: 12px;
  color: var(--text-muted);
}

.card-actions {
  display: flex;
  gap: 8px;
}

/* Empty State */
.empty-state {
  grid-column: 1 / -1;
  text-align: center;
  padding: 80px 0;
  color: var(--text-tertiary);
}

.empty-state .el-icon {
  margin-bottom: 16px;
  opacity: 0.5;
}

.empty-state h3 {
  font-size: 18px;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.empty-state p {
  font-size: 14px;
}

/* Responsive */
@media (max-width: 768px) {
  .filters {
    flex-direction: column;
  }

  .search-box {
    max-width: 100%;
  }

  .type-select {
    width: 100%;
  }

  .dataset-grid {
    grid-template-columns: 1fr;
  }
}
</style>
