import { Actor } from './actor.js';
import { Graph, Vertex } from './graph.js';
import params from './params.js';

class PostVertex extends Vertex {
  constructor(forum, authorId, postContent) {
    super();
    this.forum = forum;
    this.id = postContent.id;
    this.authorId = authorId;
    this.citations = postContent.citations;
    this.value = 0;
  }

  onValidate({ tokensMinted }) {
    this.value = params.initialPostValueFunction({ tokensMinted });
    this.forum.distributeReputation(this, this.value);
  }
}

/**
 * Purpose: Maintain a directed, acyclic, weighted graph of posts referencing other posts
 */
export class Forum extends Actor {
  constructor(bench, name, scene) {
    super(name, scene);
    this.bench = bench;
    this.posts = new Graph();
  }

  async addPost(authorId, postContent) {
    const post = new PostVertex(this, authorId, postContent);
    this.posts.addVertex(post.id, post);
    for (const { postId: citedPostId, weight } of postContent.citations) {
      this.posts.addEdge('citation', post.id, citedPostId, { weight });
    }
  }

  getPost(postId) {
    return this.posts.getVertexData(postId);
  }

  getPosts() {
    return this.posts.getVertices();
  }

  distributeReputation(post, amount, depth = 0) {
    console.log('distributeReputation', { post, amount, depth });
    // Add the given value to the current post
    post.value += amount;
    // Distribute a fraction of the added value among cited posts
    const distributeAmongCitations = amount * params.citationFraction;

    // Here we allow an arbitrary scale for the amount of the citations.
    // We normalize by dividing each by the total.
    const totalWeight = post.citations
      ?.map(({ weight }) => weight)
      .reduce((acc, cur) => (acc += cur), 0);

    for (const {
      to: citedPostId,
      data: { weight },
    } of post.getEdges('citation', true)) {
      const citedPost = this.getPost(citedPostId);
      if (!citedPost) {
        throw new Error(
          `Post ${post.postId} cites unknown post ${citedPostId}`,
        );
      }
      this.distributeReputation(
        citedPost,
        (weight / totalWeight) * distributeAmongCitations,
        depth + 1,
      );
    }
  }
}