<template>
  <main class="article-page">
    <section class="article-hero" :style="heroStyle">
      <div class="article-hero-mask">
        <div class="mx-auto max-w-screen-xl px-4 py-8">
          <a-breadcrumb class="article-breadcrumb">
            <a-breadcrumb-item>
              <NuxtLink to="/">首页</NuxtLink>
            </a-breadcrumb-item>
            <a-breadcrumb-item v-if="parentName">{{ parentName }}</a-breadcrumb-item>
            <a-breadcrumb-item>{{ pageTitle }}</a-breadcrumb-item>
          </a-breadcrumb>

          <div class="article-hero-title">{{ pageTitle }}</div>

          <div class="article-hero-meta">
            <a-tag v-if="typeof total === 'number'" color="green">共 {{ total }} 篇</a-tag>
            <a-tag v-if="keywords" color="blue">关键词：{{ keywords }}</a-tag>
          </div>

          <div class="mt-4 flex flex-wrap items-center gap-2">
            <a-input
              v-model:value="keywordInput"
              allow-clear
              class="w-full sm:w-80"
              placeholder="搜索标题/关键词"
              @press-enter="applySearch"
            />
            <a-button type="primary" @click="applySearch">搜索</a-button>
            <a-button v-if="keywords" @click="clearSearch">清除</a-button>
          </div>
        </div>
      </div>
    </section>

    <section class="mx-auto max-w-screen-xl px-4 py-10">
      <a-card class="article-card" :bordered="false">
        <a-skeleton v-if="pending" active :paragraph="{ rows: 10 }" />

        <a-result
          v-else-if="!isValidNavigationId"
          status="404"
          title="栏目不存在"
          sub-title="navigationId 无效或缺失。"
        >
          <template #extra>
            <a-space>
              <a-button type="primary" @click="navigateTo('/')">返回首页</a-button>
            </a-space>
          </template>
        </a-result>

        <a-result
          v-else-if="loadError"
          status="error"
          title="文章加载失败"
          :sub-title="loadError.message"
        >
          <template #extra>
            <a-space>
              <a-button type="primary" @click="refresh()">重试</a-button>
              <a-button @click="navigateTo('/')">返回首页</a-button>
            </a-space>
          </template>
        </a-result>

        <template v-else>
          <a-empty v-if="!articles.length" description="暂无文章" />

          <a-list v-else item-layout="vertical" size="large" :data-source="articles">
            <template #renderItem="{ item, index }">
              <a-list-item
                :key="String(item.articleId ?? item.code ?? `${String(route.params.id)}-${index}`)"
                class="article-item"
              >
                <template #extra>
                  <img
                    v-if="resolveArticleImage(item)"
                    class="article-cover"
                    :src="resolveArticleImage(item)"
                    :alt="resolveArticleTitle(item)"
                    loading="lazy"
                    @error="onImgError"
                  />
                </template>

                <a-list-item-meta :description="resolveArticleOverview(item)">
                  <template #title>
                    <NuxtLink class="article-title" :to="resolveArticleLink(item)">
                      {{ resolveArticleTitle(item) }}
                    </NuxtLink>
                  </template>
                </a-list-item-meta>

                <div class="article-meta">
                  <a-tag v-if="item.categoryName" color="default">{{ item.categoryName }}</a-tag>
                  <a-tag v-if="item.author" color="blue">{{ item.author }}</a-tag>
                  <a-tag v-if="item.createTime" color="green">{{ item.createTime }}</a-tag>
                  <a-tag v-if="typeof item.actualViews === 'number'" color="default">
                    阅读 {{ item.actualViews }}
                  </a-tag>
                  <a-tag v-if="typeof item.virtualViews === 'number'" color="default">
                    热度 {{ item.virtualViews }}
                  </a-tag>
                </div>
              </a-list-item>
            </template>
          </a-list>

          <div v-if="total > 0" class="mt-6 flex items-center justify-end">
            <a-pagination
              :current="page"
              :page-size="limit"
              :total="total"
              show-size-changer
              :page-size-options="['10', '20', '50', '100']"
              @change="onPageChange"
              @show-size-change="onPageSizeChange"
            />
          </div>
        </template>
      </a-card>
    </section>
  </main>
</template>

<script setup lang="ts">
import type { LocationQueryRaw } from 'vue-router'
import { pageCmsArticle } from '@/api/cms/cmsArticle'
import type { CmsArticle } from '@/api/cms/cmsArticle/model'
import { getCmsNavigation } from '@/api/cms/cmsNavigation'
import type { CmsNavigation } from '@/api/cms/cmsNavigation/model'

const route = useRoute()
const router = useRouter()

function parseNumberParam(raw: unknown): number {
  const text = Array.isArray(raw) ? raw[0] : raw
  const n = Number(text)
  return Number.isFinite(n) ? n : NaN
}

function parsePositiveInt(raw: unknown, fallback: number) {
  const text = Array.isArray(raw) ? raw[0] : raw
  const n = Number(text)
  if (!Number.isFinite(n)) return fallback
  const i = Math.floor(n)
  return i > 0 ? i : fallback
}

function parseQueryString(raw: unknown) {
  const text = Array.isArray(raw) ? raw[0] : raw
  return typeof text === 'string' ? text.trim() : ''
}

const navigationId = computed(() => parseNumberParam(route.params.id))
const isValidNavigationId = computed(() => Number.isFinite(navigationId.value) && navigationId.value > 0)

const page = computed(() => parsePositiveInt(route.query.page, 1))
const limit = computed(() => parsePositiveInt(route.query.limit, 10))
const keywords = computed(() => parseQueryString(route.query.q))

const keywordInput = ref(keywords.value)
watch(
  () => keywords.value,
  (v) => {
    keywordInput.value = v
  }
)

function updateQuery(next: LocationQueryRaw) {
  // Keep list state shareable via URL.
  router.replace({
    path: route.path,
    query: {
      ...route.query,
      ...next
    }
  })
}

function applySearch() {
  updateQuery({ q: keywordInput.value?.trim() || undefined, page: 1 })
}

function clearSearch() {
  keywordInput.value = ''
  updateQuery({ q: undefined, page: 1 })
}

function onPageChange(nextPage: number) {
  updateQuery({ page: nextPage })
}

function onPageSizeChange(_current: number, nextSize: number) {
  updateQuery({ limit: nextSize, page: 1 })
}

const { data: navigation } = await useAsyncData<CmsNavigation | null>(
  () => `cms-navigation-${String(route.params.id)}`,
  async () => {
    if (!isValidNavigationId.value) return null
    return await getCmsNavigation(navigationId.value).catch(() => null)
  },
  { watch: [navigationId] }
)

const {
  data: articlePage,
  pending,
  error: loadError,
  refresh
} = await useAsyncData<{ list: CmsArticle[]; count: number } | null>(
  () => `cms-article-${String(route.params.id)}-${page.value}-${limit.value}-${keywords.value}`,
  async () => {
    if (!isValidNavigationId.value) return null
    return await pageCmsArticle({
      navigationId: navigationId.value,
      page: page.value,
      limit: limit.value,
      keywords: keywords.value || undefined
    })
  },
  { watch: [navigationId, page, limit, keywords] }
)

const articles = computed(() => articlePage.value?.list ?? [])
const total = computed(() => articlePage.value?.count ?? 0)

function pickString(obj: unknown, key: string) {
  if (!obj || typeof obj !== 'object') return ''
  const record = obj as Record<string, unknown>
  const value = record[key]
  return typeof value === 'string' ? value.trim() : ''
}

const pageTitle = computed(() => {
  const name = pickString(navigation.value, 'title') || pickString(navigation.value, 'label')
  if (name) return name
  if (isValidNavigationId.value) return `栏目 ${navigationId.value}`
  return '文章列表'
})

const parentName = computed(() => pickString(navigation.value, 'parentName'))

const heroStyle = computed(() => {
  const banner = pickString(navigation.value, 'banner')
  if (banner) return { backgroundImage: `url(${banner})` }
  return {}
})

function resolveArticleTitle(a: CmsArticle) {
  return String(a.title || a.code || '未命名文章').trim()
}

function resolveArticleLink(a: CmsArticle) {
  const articleId = typeof a.articleId === 'number' && Number.isFinite(a.articleId) ? a.articleId : NaN
  const code = String(a.code || '').trim()
  return {
    path: '/article-item',
    query: {
      id: Number.isFinite(articleId) ? String(articleId) : undefined,
      code: !Number.isFinite(articleId) && code ? code : undefined,
      navId: Number.isFinite(navigationId.value) ? String(navigationId.value) : undefined,
      page: String(page.value),
      limit: String(limit.value),
      q: keywords.value || undefined
    }
  }
}

function resolveArticleImage(a: CmsArticle) {
  const img = String(a.image || '').trim()
  return img || ''
}

function resolveArticleOverview(a: CmsArticle) {
  const text = String(a.overview || '').trim()
  if (text) return text
  const fallback = String(a.detail || '').trim()
  return fallback.length > 120 ? `${fallback.slice(0, 120)}...` : fallback
}

function onImgError(e: Event) {
  const el = e.target as HTMLImageElement | null
  if (!el) return
  el.style.display = 'none'
}

const seoTitle = computed(() => `${pageTitle.value} - 文章列表`)
const seoDescription = computed(() => {
  if (keywords.value) return `${pageTitle.value} - 关键词「${keywords.value}」的文章列表`
  return `${pageTitle.value} - 文章列表`
})

useSeoMeta({
  title: seoTitle,
  description: seoDescription,
  ogTitle: seoTitle,
  ogDescription: seoDescription,
  ogType: 'website'
})

const canonicalUrl = computed(() => {
  if (import.meta.client) return window.location.href
  try {
    return useRequestURL().href
  } catch {
    return ''
  }
})

useHead(() => ({
  link: canonicalUrl.value ? [{ rel: 'canonical', href: canonicalUrl.value }] : []
}))
</script>

<style scoped>
.article-page {
  background: #f4f6f8;
}

.article-hero {
  background:
    radial-gradient(circle at 15% 20%, rgba(22, 163, 74, 0.22), transparent 60%),
    radial-gradient(circle at 85% 10%, rgba(59, 130, 246, 0.18), transparent 55%),
    linear-gradient(180deg, #ffffff, #f8fafc);
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.article-hero-mask {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.88), rgba(255, 255, 255, 0.92));
}

.article-breadcrumb {
  color: rgba(0, 0, 0, 0.6);
}

.article-hero-title {
  margin-top: 10px;
  font-size: 30px;
  font-weight: 900;
  color: rgba(0, 0, 0, 0.88);
  line-height: 1.2;
}

.article-hero-meta {
  margin-top: 10px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.article-card {
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 10px 28px rgba(0, 0, 0, 0.06);
}

.article-item :deep(.ant-list-item-extra) {
  margin-inline-start: 24px;
}

.article-title {
  font-size: 18px;
  font-weight: 800;
  color: rgba(0, 0, 0, 0.88);
  text-decoration: none;
}

.article-meta {
  margin-top: 10px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.article-cover {
  width: 220px;
  height: 140px;
  object-fit: cover;
  border-radius: 10px;
  border: 1px solid rgba(0, 0, 0, 0.06);
}

@media (max-width: 640px) {
  .article-item :deep(.ant-list-item-extra) {
    margin-inline-start: 0;
    margin-top: 12px;
    width: 100%;
  }

  .article-cover {
    width: 100%;
    height: 200px;
  }
}
</style>
