import { QuartzEmitterPlugin } from "../types"
import { QuartzComponentProps } from "../../components/types"
import HeaderConstructor from "../../components/Header"
import BodyConstructor from "../../components/Body"
import { pageResources, renderPage } from "../../components/renderPage"
import { ProcessedContent, defaultProcessedContent } from "../vfile"
import { FullPageLayout } from "../../cfg"
import path from "path"
import { CanonicalSlug, FilePath, ServerSlug, canonicalizeServer, joinSegments } from "../../path"

export const FolderPage: QuartzEmitterPlugin<FullPageLayout> = (opts) => {
  if (!opts) {
    throw new Error("ErrorPage must be initialized with options specifiying the components to use")
  }

  const { head: Head, header, beforeBody, pageBody: Content, left, right, footer: Footer } = opts
  const Header = HeaderConstructor()
  const Body = BodyConstructor()

  return {
    name: "FolderPage",
    getQuartzComponents() {
      return [Head, Header, Body, ...header, ...beforeBody, Content, ...left, ...right, Footer]
    },
    async emit(ctx, content, resources, emit): Promise<FilePath[]> {
      const fps: FilePath[] = []
      const allFiles = content.map((c) => c[1].data)
      const cfg = ctx.cfg.configuration

      const folders: Set<CanonicalSlug> = new Set(
        allFiles.flatMap((data) => {
          const slug = data.slug
          const folderName = path.dirname(slug ?? "") as CanonicalSlug
          if (slug && folderName !== "." && folderName !== "tags") {
            return [folderName]
          }
          return []
        }),
      )

      const folderDescriptions: Record<string, ProcessedContent> = Object.fromEntries(
        [...folders].map((folder) => [
          folder,
          defaultProcessedContent({
            slug: joinSegments(folder, "index") as ServerSlug,
            frontmatter: { title: `Folder: ${folder}`, tags: [] },
          }),
        ]),
      )

      for (const [tree, file] of content) {
        const slug = canonicalizeServer(file.data.slug!)
        if (folders.has(slug)) {
          folderDescriptions[slug] = [tree, file]
        }
      }

      for (const folder of folders) {
        const slug = folder
        const externalResources = pageResources(slug, resources)
        const [tree, file] = folderDescriptions[folder]
        const componentData: QuartzComponentProps = {
          fileData: file.data,
          externalResources,
          cfg,
          children: [],
          tree,
          allFiles,
        }

        const content = renderPage(slug, componentData, opts, externalResources)

        const fp = (file.data.slug! + ".html") as FilePath
        await emit({
          content,
          slug: file.data.slug!,
          ext: ".html",
        })

        fps.push(fp)
      }
      return fps
    },
  }
}