import type { AstroIntegration, RouteOptions } from 'astro';
import fs from 'node:fs';
import path from 'node:path';
import url from 'node:url';
import type { Literal, Node, Parent } from 'unist';
import { selectAll } from 'unist-util-select';
import options from '../options';
import { urlJoin } from '../src/helpers/tools';

export const rootImages = (): AstroIntegration => ({
  name: 'Root Images',
  hooks: {
    'astro:build:generated': ({ dir }) => {
      fs.cpSync(path.join(process.cwd(), 'images'), path.join(url.fileURLToPath(dir), 'images'), { recursive: true });
    },
  },
});

export const openGraph = (): AstroIntegration => ({
  name: 'Open Graph Generator',
  hooks: {
    'astro:route:setup': (options: { route: RouteOptions }) => {
      if (options.route.component === 'src/pages/images/og/[slug].png.ts') {
        options.route.prerender = process.env.BUILD_OPEN_GRAPH === undefined || process.env.BUILD_OPEN_GRAPH === 'true';
      }
    },
  },
});

type LinkNode = Node & {
  url: string;
  children?: ImageNode[];
};

type ImageNode = Parent & {
  url: string;
  alt: string;
  name: string;
  width?: number;
  height?: number;
  attributes: (Literal & { name: string })[];
};

export const astroImage = () => {
  return (tree: Node) => {
    // Find all the image node.
    // Find all the image link nodes and replace the relative links.
    selectAll('image', tree)
      .map((node) => node as ImageNode)
      .filter((imageNode) => imageNode.url.startsWith('/'))
      .map((imageNode) => {
        imageNode.type = 'mdxJsxFlowElement';
        imageNode.name = 'Image';

        imageNode.attributes = [
          { type: 'mdxJsxAttribute', name: 'alt', value: imageNode.alt },
          { type: 'mdxJsxAttribute', name: 'src', value: imageNode.url },
          { type: 'mdxJsxAttribute', name: 'width', value: imageNode.width },
          { type: 'mdxJsxAttribute', name: 'height', value: imageNode.height },
        ];
      });

    for (const node of selectAll('link', tree)) {
      const link = node as LinkNode;
      if (link.children !== undefined && link.children.length !== 0) {
        const images = link.children.filter((child) => child.type === 'mdxJsxFlowElement' && child.name === 'Image');
        if (images.length > 0) {
          link.url = link.url.startsWith('/') ? urlJoin(options.assetsPrefix(), link.url) : link.url;
        }
      }
    }
    return tree;
  };
};