server.js

const express = require('express');
const axios = require('axios');
const fs = require('fs');
const path = require('path');
const app = express();

const port = 3005;

app.use(express.static('public'));
app.use(express.json());

app.get('/', (req, res) => {
  console.log('Received GET request for /');
  res.sendFile(path.join(__dirname, 'public', 'index.html'));
});

app.post('/convert', async (req, res) => {
  try {
    const { link } = req.body;
    console.log(`Received POST request to convert link: ${link}`);

    const url = `${link}.json`;
    console.log(`URL requested: ${url}`);

    const response = await axios.get(url);
    const data = response.data;
    console.log('Successfully fetched data from Reddit API');
    const responseJson = JSON.stringify(data, null, 4);

    // save responseJson to a file
    const linkFileName = link.replace(/[^a-zA-Z0-9]/g, '_');
    fs.writeFileSync(`response-${linkFileName}.json`, responseJson);


    console.log("Creating obsidian canvas");

    const obsidianCanvas = redditToObsidianCanvas(data);
    const obsidianCanvasJson = JSON.stringify(obsidianCanvas, null, 4);
    fs.writeFileSync(`canvas-${linkFileName}.canvas`, obsidianCanvasJson);
    console.log(`Created obsidian canvas: canvas-${linkFileName}.canvas`);

    let markdown = '';
    const post = data[0].data.children[0].data;

    markdown += `# ${post.title}\n\n`;
    markdown += `${post.selftext}\n\n`;

    const comments = data[1].data.children;
    for (const comment of comments) {
      if (comment.kind === 't1') {
        markdown += `## ${comment.data.author}\n\n${comment.data.body}\n\n`;
      }
    }

    console.log('Successfully converted data to markdown');
    res.json({ markdown });
  } catch (error) {
    console.error('Error during conversion:', error.message);
    res.status(500).json({ error: error.message });
  }
});


function redditToObsidianCanvas(redditJson) {
  let currentY = 0;  // Track the current Y position globally

  let nodes = [];
  let edges = [];
  let yOffset = 0;  // Global offset to manage Y positions

  function createNode(id, text, x, y) {

    const minHeight = 100;  // Minimum height of the node
    const lineHeight = 20;  // Approximate height per line of text

    // Calculate the number of lines (assuming ~50 characters per line for estimation)
    const numberOfLines = Math.ceil(text.length / 20); // this is duplicated with numberOfLines in processComment

    // Calculate the height based on the number of lines
    const calculatedHeight = Math.max(minHeight, numberOfLines * lineHeight);

    return {
      id: id,
      type: "text",
      x: x,
      y: y,
      width: 300,
      height: calculatedHeight,
      text: text,
      color: "#FFD700"
    };
  }

  function processComment(comment, parentId = null, x = 0, y = 0, depth = 0) {
    const commentId = uuidv4();
    const nodeText = `${comment.author}: ${comment.body}`;

    // Calculate the height of the current node
    const minHeight = 100;  // Minimum height of the node
    const lineHeight = 20;  // Approximate height per line of text
    const numberOfLines = Math.ceil(nodeText.length / 20); // changed 50 to 20 for more lines
    const nodeHeight = Math.max(minHeight, numberOfLines * lineHeight);

    // Create the node with the updated currentY position
    nodes.push(createNode(commentId, nodeText, x, currentY));

    // Update currentY for the next node to avoid overlap
    currentY += nodeHeight + 50;  // Add extra spacing of 50 pixels

    // Create an edge between the parent and this comment
    if (parentId !== null) {
      edges.push({
        id: uuidv4(),
        fromNode: parentId,
        toNode: commentId,
        fromSide: "right",
        toSide: "left"
      });
    }

    // Process replies if any
    if (comment.replies && comment.replies.data && comment.replies.data.children) {
      comment.replies.data.children.forEach(reply => {
        if (reply.kind === 't1') {  // It's a comment
          processComment(reply.data, commentId, x + 400, currentY, depth + 1);
        }
      });
    }
  }

  // Process the main post
  redditJson[0].data.children.forEach(child => {
    const post = child.data;
    const postId = uuidv4();
    const postText = `${post.author}: ${post.title}\n${post.selftext}`;
    nodes.push(createNode(postId, postText, 0, yOffset));  // Use yOffset to place the post

    // Process comments
    let commentY = yOffset + 150;
    redditJson[1].data.children.forEach(comment => {
      if (comment.kind === 't1') {  // It's a comment
        processComment(comment.data, postId, 400, commentY);
        commentY += 150;  // Increment Y for the next top-level comment
      }
    });

    // Update yOffset for the next post (if any)
    yOffset = commentY;
  });

  // Prepare the final canvas data
  return {
    nodes: nodes,
    edges: edges
  };
}

// Helper function to generate unique IDs
function uuidv4() {
  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function (c) {
    const r = Math.random() * 16 | 0, v = c == 'x' ? r : (r & 0x3 | 0x8);
    return v.toString(16);
  });
}

// Output the canvas JSON
// fs.writeFileSync('output_canvas.json', JSON.stringify(canvasJson, null, 4));

app.listen(port, () => {
  console.log(`Server running at http://localhost:${port}`);
});