gatsby-node.ts

import path from 'path';
import type { GatsbyNode } from 'gatsby';

interface PageInput {
  path: string;
  component: string;
  context?: Record<string, any>;
}

interface MdxNode {
  id: string;
  frontmatter: {
    slug: string;
  };
  internal: {
    contentFilePath: string;
  };
}

// remove duplicate pages generated by Gatsby for keeping subfolder organization, but not affecting SEO
export const onCreatePage: GatsbyNode['onCreatePage'] = ({ page, actions }) => {
  const { deletePage } = actions;
  if (
    page.path.startsWith('/main/') ||
    page.path.startsWith('/posts/') ||
    page.path.startsWith('/extras/') ||
    page.path.startsWith('/freelance-subpages/')
  ) {
    deletePage(page);
  }
};

// avoid conflicting order for styles (removes warnings from console)
export const onCreateWebpackConfig: GatsbyNode['onCreateWebpackConfig'] = ({ actions, getConfig }) => {
  const config = getConfig();
  config.plugins.forEach((plugin: any) => {
    if (plugin.constructor.name === "MiniCssExtractPlugin") {
      plugin.options.ignoreOrder = true;
    }
  });
  actions.replaceWebpackConfig(config);
};

export const createPages: GatsbyNode['createPages'] = async ({ actions, graphql }) => {
  const { createPage } = actions;

  const result = await graphql<{ allMdx: { nodes: MdxNode[] } }>(`
    {
      allMdx {
        nodes {
          id
          frontmatter {
            slug
          }
          internal {
            contentFilePath
          }
        }
      }
    }
  `);

  if (result.errors) {
    throw new Error(result.errors.join('\n'));
  }

  const excludedFiles = [
    'adventures_template.mdx',
    'research_template.mdx',
    'thoughts_template.mdx'
  ];

  // process mdx files of posts by checking if the contentFilePath includes 'src/pages/posts', but not excludedFiles
  result.data?.allMdx.nodes.forEach((node) => {
    if (excludedFiles.some((templateName) => node.internal.contentFilePath.includes(templateName))) { 
      return;
    }

    if (node.internal.contentFilePath.includes('src/pages/posts')) {
      const PostTemplate = process.env.NODE_ENV === "development"
        ? path.resolve(`./src/templates/post_development.tsx`)
        : path.resolve(`./src/templates/post.tsx`);

      const slug = node.frontmatter.slug;
      const slugParts = slug.split('/').filter(part => part !== '');
      const section = slugParts[0];
      const postName = slugParts[1];
      const postsFilterRegex = `/${section}/`;
      
      createPage({
        path: node.frontmatter.slug, 
        component: `${PostTemplate}?__contentFilePath=${node.internal.contentFilePath}`,
        context: { 
          id: node.id,
          postsFilterRegex,
          imagePathRegex: `^posts/${section}/content/${postName}/`,
        },
      });
    }
  });

  // helper function to create pages with proper TypeScript typing
  const createTypedPage = (pageInput: PageInput) => {
    createPage(pageInput);
  };

  createTypedPage({path: "/frog", component: path.resolve(`src/components/NotFound/index.tsx`)});
  createTypedPage({path: "/adventures", component: path.resolve(`src/pages/main/adventures.tsx`)});
  createTypedPage({path: "/research", component: path.resolve(`src/pages/main/research.tsx`)});
  createTypedPage({path: "/thoughts", component: path.resolve(`src/pages/main/thoughts.tsx`)});
  createTypedPage({path: "/tags", component: path.resolve(`src/pages/main/tags.tsx`)});
  createTypedPage({path: "/handbook", component: path.resolve(`src/pages/main/travel_handbook.tsx`)});
  createTypedPage({path: "/publications", component: path.resolve(`src/pages/main/publications.tsx`)});
  createTypedPage({path: "/software", component: path.resolve(`src/pages/main/software.tsx`)});
  createTypedPage({path: "/music", component: path.resolve(`src/pages/main/music.tsx`)});
  createTypedPage({path: "/course", component: path.resolve(`src/pages/main/course.tsx`)});
  createTypedPage({path: "/talks", component: path.resolve(`src/pages/main/talks.tsx`)});
  createTypedPage({path: "/goals", component: path.resolve(`src/pages/main/goals.tsx`)});
  createTypedPage({path: "/exploration", component: path.resolve(`src/pages/main/exploration.tsx`)});
  createTypedPage({path: "/freelance", component: path.resolve(`src/pages/main/freelance.tsx`)});
  createTypedPage({path: "/freelance/ru", component: path.resolve(`src/pages/main/freelance_ru.tsx`)});
  createTypedPage({path: "/freelance/services", component: path.resolve(`src/pages/freelance-subpages/services.mdx`)});
  createTypedPage({path: "/freelance/ru/services", component: path.resolve(`src/pages/freelance-subpages/services_ru.mdx`)});
  createTypedPage({path: "/freelance/projects/machine_learning", component: path.resolve(`src/pages/freelance-subpages/machine_learning.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/machine_learning", component: path.resolve(`src/pages/freelance-subpages/machine_learning_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/data_analysis", component: path.resolve(`src/pages/freelance-subpages/data_analysis.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/data_analysis", component: path.resolve(`src/pages/freelance-subpages/data_analysis_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/data_visualization", component: path.resolve(`src/pages/freelance-subpages/data_visualization.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/data_visualization", component: path.resolve(`src/pages/freelance-subpages/data_visualization_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/data_collection", component: path.resolve(`src/pages/freelance-subpages/data_collection.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/data_collection", component: path.resolve(`src/pages/freelance-subpages/data_collection_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/python_apps", component: path.resolve(`src/pages/freelance-subpages/python_apps.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/python_apps", component: path.resolve(`src/pages/freelance-subpages/python_apps_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/web_development", component: path.resolve(`src/pages/freelance-subpages/web_development.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/web_development", component: path.resolve(`src/pages/freelance-subpages/web_development_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/research", component: path.resolve(`src/pages/freelance-subpages/research.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/research", component: path.resolve(`src/pages/freelance-subpages/research_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/technical_writing", component: path.resolve(`src/pages/freelance-subpages/technical_writing.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/technical_writing", component: path.resolve(`src/pages/freelance-subpages/technical_writing_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/post_production", component: path.resolve(`src/pages/freelance-subpages/post_production.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/post_production", component: path.resolve(`src/pages/freelance-subpages/post_production_ru.tsx`)});
  createTypedPage({path: "/freelance/projects/misc", component: path.resolve(`src/pages/freelance-subpages/misc.tsx`)});
  createTypedPage({path: "/freelance/ru/projects/misc", component: path.resolve(`src/pages/freelance-subpages/misc_ru.tsx`)});
  createTypedPage({path: "/cv", component: path.resolve(`src/pages/main/cv.tsx`)});
  createTypedPage({path: "/about", component: path.resolve(`src/pages/main/about.tsx`)});
  createTypedPage({path: "/gallery", component: path.resolve(`src/pages/main/gallery.tsx`)});
  createTypedPage({path: "/stories", component: path.resolve(`src/pages/main/stories.tsx`)});
  createTypedPage({path: "/zettelkasten", component: path.resolve(`src/pages/main/zettelkasten.tsx`)});
  createTypedPage({path: "/articles", component: path.resolve(`src/pages/main/articles.tsx`)});
  createTypedPage({path: "/websites", component: path.resolve(`src/pages/main/websites.tsx`)});
  createTypedPage({path: "/videos", component: path.resolve(`src/pages/main/videos.tsx`)});
  createTypedPage({path: "/feed", component: path.resolve(`src/pages/main/feed.tsx`)});
  createTypedPage({path: "/playlists", component: path.resolve(`src/pages/main/playlists.tsx`)});
  createTypedPage({path: "/albums", component: path.resolve(`src/pages/main/albums.tsx`)});
  createTypedPage({path: "/films", component: path.resolve(`src/pages/main/films.tsx`)});
  createTypedPage({path: "/bookshelf", component: path.resolve(`src/pages/main/bookshelf.tsx`)});
  createTypedPage({path: "/hall_of_fame", component: path.resolve(`src/pages/main/hall_of_fame.tsx`)});
  createTypedPage({path: "/gear", component: path.resolve(`src/pages/main/gear.tsx`)});
  createTypedPage({path: "/calisthenics", component: path.resolve(`src/pages/main/calisthenics.tsx`)});
  createTypedPage({path: "/friends", component: path.resolve(`src/pages/main/friends.tsx`)});
  createTypedPage({path: "/habits", component: path.resolve(`src/pages/main/habits.tsx`)});
  createTypedPage({path: "/faq", component: path.resolve(`src/pages/main/faq.tsx`)});
  createTypedPage({path: "/information_for_business_inquiries", component: path.resolve(`src/pages/extras/information_for_business_inquiries.tsx`)});
  createTypedPage({path: "/donate", component: path.resolve(`src/pages/extras/donate.tsx`)});
  createTypedPage({path: "/contact", component: path.resolve(`src/pages/extras/contact.tsx`)});
  createTypedPage({path: "/all", component: path.resolve(`src/pages/extras/all_posts.tsx`)});
  createTypedPage({path: "/dev", component: path.resolve(`src/pages/extras/dev.tsx`)});
  createTypedPage({path: "/dev/null", component: path.resolve(`src/pages/extras/dev_null.tsx`)});
  createTypedPage({path: "/dev/magnitoshakhtinsk", component: path.resolve(`src/pages/extras/dev_magnitoshakhtinsk.tsx`)});
  createTypedPage({path: "/null", component: path.resolve(`src/pages/extras/dev_null.tsx`)});
  createTypedPage({path: "/avrtt", component: path.resolve(`src/pages/extras/avrtt.tsx`)});
};