import { HandlerContext } from "$fresh/server.ts";
import {
  createDocument,
  getDocument,
  transformDocument,
} from "@lib/documents.ts";
import { fileExtension } from "https://deno.land/x/file_extension@v2.1.0/mod.ts";
import { type Movie, parseMovie } from "@lib/movies.ts";
import * as tmdb from "@lib/tmdb.ts";
import { parse, stringify } from "https://deno.land/std@0.194.0/yaml/mod.ts";
import { formatDate } from "@lib/string.ts";

function safeFileName(inputString: string): string {
  // Convert the string to lowercase
  let fileName = inputString.toLowerCase();

  // Replace spaces with underscores
  fileName = fileName.replace(/ /g, "_");

  // Remove characters that are not safe for file names
  fileName = fileName.replace(/[^\w.-]/g, "");

  return fileName;
}

export async function getMovie(name: string) {
  const document = await getDocument(`Media/movies/${name}.md`);

  const movie = parseMovie(document, name);

  return movie;
}

async function updateMovieMetadata(
  name: string,
  metadata: Partial<Movie["meta"]>,
) {
  const docId = `Media/movies/${name}.md`;

  const currentDoc = await getDocument(docId);
  if (!currentDoc) return;

  const newDoc = transformDocument(currentDoc, (root) => {
    const frontmatterNode = root.children.find((c) => c.type === "yaml");

    const frontmatter = frontmatterNode?.value as string;

    if (frontmatter) {
      const value = parse(frontmatter) as Movie["meta"];

      if (metadata.author && !value.author) {
        value.author = metadata.author;
      }

      if (metadata.image && !value.image) {
        value.image = metadata.image;
      }

      if (metadata.date && !value.date) {
        value.date = formatDate(metadata.date);
      }
      frontmatterNode.value = stringify(value);
    }

    return root;
  });

  const response = await createDocument(docId, newDoc);

  return response;
}

export const handler = async (
  _req: Request,
  _ctx: HandlerContext,
): Promise<Response> => {
  const headers = new Headers();
  headers.append("Content-Type", "application/json");

  const movie = await getMovie(_ctx.params.name);

  if (_req.method === "GET") {
    return new Response(JSON.stringify(movie));
  }

  if (_req.method === "POST") {
    const body = await _req.json();
    const name = _ctx.params.name;
    const { tmdbId } = body;
    if (!name || !tmdbId) {
      return new Response("Bad Request", {
        status: 400,
      });
    }

    const movieDetails = await tmdb.getMovie(tmdbId);
    const movieCredits = !movie.meta.author &&
      await tmdb.getMovieCredits(tmdbId);

    const releaseDate = movieDetails.release_date;
    const posterPath = movieDetails.poster_path;
    const director = movieCredits?.crew?.filter?.((person) =>
      person.job === "Director"
    )[0];

    let finalPath = "";
    if (posterPath && !movie.meta.image) {
      const poster = await tmdb.getMoviePoster(posterPath);
      const extension = fileExtension(posterPath);

      finalPath = `Media/movies/images/${
        safeFileName(name)
      }_cover.${extension}`;
      await createDocument(finalPath, poster);
    }

    const metadata = {} as Movie["meta"];
    if (releaseDate) {
      metadata.date = new Date(releaseDate);
    }
    if (finalPath) {
      metadata.image = finalPath;
    }
    if (director) {
      metadata.author = director.name;
    }

    await updateMovieMetadata(name, metadata);

    return new Response(JSON.stringify(movieCredits), {
      headers,
    });
  }

  return new Response();
};