@graffy/common/esm/build/graph.js

Common libraries that used by various Graffy modules.

import { merge } from '../graph';
import { makePath } from '../path';
import { isRange } from '../node';
import { encodeKey } from '../encode';

function makeGraph(key, value, version) {
  if (typeof value === 'function') {
    // This is a page or a link waiting for a version.
    return value(key, version);
  } else if (Array.isArray(value)) {
    // Convert the KV-tuple format to a graph
    return {
      key,
      version,
      children: value.map(({
        key: k,
        name,
        value: v,
        children,
        path
      }) => makeGraph(name || encodeKey(k), children || path && link(path) || v && scalar(v), version)).sort((a, b) => a.key <= b.key ? -1 : 1)
    };
  } else if (value === null) {
    // This is a single key known to be missing.
    return {
      key,
      end: key,
      version
    };
  } else if (typeof value === 'object' && value) {
    return {
      key,
      version,
      children: Object.keys(value).sort().map(k => makeGraph(k, value[k], version))
    };
  } else {
    return {
      key,
      version,
      value
    };
  }
}

export function graph(obj, version = Date.now()) {
  // console.log('makeGraph called with', obj);
  if (!obj) return obj;
  return makeGraph('', obj, version).children;
}
export function page(obj, key = '', end = '\uffff') {
  return (outerKey, version) => {
    const nodes = graph(obj, version);
    const gaps = merge([{
      key,
      end,
      version
    }], Object.keys(obj).map(key => ({
      key,
      value: 1,
      version
    }))).filter(node => isRange(node));
    const children = merge(nodes, gaps);
    return {
      key: outerKey,
      version,
      children
    };
  };
}
export function link(rawPath) {
  const path = makePath(rawPath);
  return (key, version) => ({
    key,
    version,
    path
  });
}
export function scalar(value) {
  return (key, version) => ({
    key,
    version,
    value
  });
}