atjson hir rewrite

tree.ts

class Tree {
  label: string;
  rank: number;
  start: number;
  end: number;
  private children: Tree[];

  constructor(params: {
    label: string,
    start: number,
    end: number,
    rank: number
  }) {
    this.children = [];
    this.label = params.label;
    this.start = params.start;
    this.end = params.end;
    this.rank = params.rank;
  }

  // Currently assumes that nodes are sorted by rank
  insert(node: Tree) {
    for (let i = 0, len = this.children.length; i < len; i++) {
      let child = this.children[i];
      if (node.start < child.start) {
        // Splice in the full node and return if it's wholly
        // before this child
        if (node.end <= child.start) {
          this.children.splice(i, 0, node);
          i++;
          return;
        }
        // Otherwise, we have a left branch to take care of
        let [leftBranch, rest] = node.split(child.start);

        // Insert the branch
        this.children.splice(i, 0, leftBranch);
        i++;

        // Continue with partial node (to the next statement,
        // since this may extend past this node)
        if (rest == null) break;
        node = rest;
      }

      if (node.start >= child.start && node.start < child.end) {
        if (node.end <= child.end) {
          child.insert(node);
          return;
        }
        let [rightBranch, rest] = node.split(child.end);
        // Insert the branch
        child.insert(rightBranch);

        if (rest == null) break;
        // Continue with partial node
        node = rest;
      }
    }

    this.children.push(node);
  }

  split(at: number): [Tree, Tree] {
    if (this.rank === Infinity) {
      return [
        new Tree({
          label: this.label.slice(0, at - this.start),
          start: this.start,
          end: at,
          rank: this.rank
        }),
        new Tree({
          label: this.label.slice(at - this.start),
          start: at,
          end: this.end,
          rank: this.rank
        })
      ];
    }
    return [
      new Tree({
        label: this.label,
        start: this.start,
        end: at,
        rank: this.rank
      }),
      new Tree({
        label: this.label,
        start: at,
        end: this.end,
        rank: this.rank
      })
    ];
  }

  toJSON(): any {
    return {
      label: this.label,
      start: this.start,
      end: this.end,
      children: this.children.map(child => child.toJSON())
    };
  }

  trace(indent=0): any {
    // @ts-ignore
    let spacing = '  '.repeat(indent);
    if (this.rank === Infinity) {
      return `${spacing}${JSON.stringify(this.label)}`;
    }
    let children = this.children.map(child => child.trace(indent + 1));
    if (children.length === 0) {
      return `${spacing}${this.label}[${this.start}, ${this.end}]()`;
    } else {
      return `${spacing}${this.label}[${this.start}, ${this.end}](\n${children.join('\n')}\n${spacing})`;
    }
  }
}

let tree = new Tree({ label: 'document', start: 0, end: 10, rank: 0 });
tree.insert(new Tree({ label: 'ol', start: 4, end: 8, rank: 10 }));
tree.insert(new Tree({ label: 'li', start: 4, end: 8, rank: 10 }));
tree.insert(new Tree({ label: 'paragraph', start: 0, end: 4, rank: 15 }));
tree.insert(new Tree({ label: 'paragraph', start: 8, end: 10, rank: 15 }));
tree.insert(new Tree({ label: 'paragraph', start: 4, end: 8, rank: 15 }));
tree.insert(new Tree({ label: 'ab\n\nli\n\ncd', start: 0, end: 10, rank: Infinity }));

console.log(tree.trace())