import { renderToString } from 'vue/server-renderer'
import { createApp } from './main'
import { createSSRContext } from 'x/composables/ssrContext'
import { basename } from 'node:path'
import { createHead } from '@unhead/vue/server'

export async function render(url: string, manifest: any, init?: { cookies?: Record<string, string> }) {
  // 创建 SSR 上下文，包含数据缓存与 cookies
  const ssrContext = createSSRContext()
  if (init?.cookies) {
    ssrContext.cookies = { ...init.cookies }
  }

  // 将 SSR 上下文传递给应用创建函数
  const { app, pinia, router } = createApp(ssrContext)

  const unHead = createHead({
    disableDefaults: true
  })
  app.use(unHead)

  // https://github.com/antfu-collective/vitesse
  // https://github.com/unjs/unhead/blob/main/examples/vite-ssr-vue/src/entry-server.ts
  useSeoMeta({
    title: 'My Awesome Site',
    description: 'My awesome site description',
  }, { head: unHead })

  useHead({
    title: "aa",
    htmlAttrs: {
      lang: "zh-CN"
    },
    meta: [
      {
        charset: "UTF-8"
      },
      {
        name: "viewport",
        content: "width=device-width, initial-scale=1.0",
      },
      {
        name: "description",
        content: "Welcome to our website",
      },
    ],
    link: [
      {
        rel: "icon",
        type: "image/svg+xml",
        // href: () => (preferredDark.value ? "/favicon-dark.svg" : "/favicon.svg"),
        href: () => "/vite.svg",
      },
    ],
  }, { head: unHead })

  router.push(url); // 根据请求 URL 设置路由
  await router.isReady(); // 等待路由准备完成

  // passing SSR context object which will be available via useSSRContext()
  // @vitejs/plugin-vue injects code into a component's setup() that registers
  // itself on ctx.modules. After the render, ctx.modules would contain all the
  // components that have been instantiated during this render call.
  const ctx = { cache: ssrContext.cache }
  const html = await renderToString(app, ctx)

  // 将 SSR 上下文数据序列化到 HTML 中
  // 使用更安全的方式序列化 Map
  const cacheEntries = ssrContext.cache ? Array.from(ssrContext.cache.entries()) : []
  const ssrData = JSON.stringify(cacheEntries)

  // @ts-ignore
  const preloadLinks = renderPreloadLinks(ctx.modules, manifest)

  console.log('[SSR] 序列化缓存数据:', cacheEntries)

  const head = `
    <script>
      window.__SSR_CONTEXT__ = {
        cache: new Map(${ssrData}),
        piniaState: ${JSON.stringify(pinia.state.value || {})}
      };
    </script>
    ${preloadLinks}
  `

  return { html, head, unHead, setCookies: ssrContext.setCookies || [] }
}

function renderPreloadLinks(modules: any, manifest: any) {
  let links = ''
  const seen = new Set()
  modules.forEach((id: any) => {
    const files = manifest[id]
    if (files) {
      files.forEach((file: any) => {
        if (!seen.has(file)) {
          seen.add(file)
          const filename = basename(file)
          if (manifest[filename]) {
            for (const depFile of manifest[filename]) {
              links += renderPreloadLink(depFile)
              seen.add(depFile)
            }
          }
          links += renderPreloadLink(file)
        }
      })
    }
  })
  return links
}

function renderPreloadLink(file: string) {
  if (file.endsWith('.js')) {
    return `<link rel="modulepreload" crossorigin href="${file}">`
  } else if (file.endsWith('.css')) {
    return `<link rel="stylesheet" href="${file}">`
  } else if (file.endsWith('.woff')) {
    return ` <link rel="preload" href="${file}" as="font" type="font/woff" crossorigin>`
  } else if (file.endsWith('.woff2')) {
    return ` <link rel="preload" href="${file}" as="font" type="font/woff2" crossorigin>`
  } else if (file.endsWith('.gif')) {
    return ` <link rel="preload" href="${file}" as="image" type="image/gif">`
  } else if (file.endsWith('.jpg') || file.endsWith('.jpeg')) {
    return ` <link rel="preload" href="${file}" as="image" type="image/jpeg">`
  } else if (file.endsWith('.png')) {
    return ` <link rel="preload" href="${file}" as="image" type="image/png">`
  } else {
    return ''
  }
}