@pg-english/entity/index.js

Process text to entity tokens.

const token = require('@pg-english/token');
const T = token.type;

const TYPE = new Map([
  ['t', T.TABLE],
  ['c', T.COLUMN],
  ['r', T.ROW],
]);

async function blockScan(txts, fn, ths=null) {
  for(var i=0, I=txts.length, z=[]; i<I;) {
    var ans = await fn.call(ths, txts.slice(i, I));
    if(ans==null) { z.push(token(T.TEXT, txts[i++])); continue; }
    var typ = TYPE.get(ans.type[0].toLowerCase())||0;
    z.push(token(typ, ans.value, ans.hint||null)); i += ans.length;
  }
  return z;
};
async function process(tkns, fn, ths=null) {
  var z = [], blk = [], txts = [];
  for(var tkn of tkns) {
    if((tkn.type&0xF0)===T.TEXT) { txts.push(tkn.value); continue; }
    if(txts.length>0) { blk.push(blockScan(txts, fn, ths)); txts = []; }
    blk.push([tkn]);
  }
  if(txts.length>0) blk.push(blockScan(txts, fn, ths));
  var ans = await Promise.all(blk);
  for(var arr of ans)
    z.push.apply(z, arr);
  return z;
};

async function entity(txt, fn, ths=null) {
  return token.toString(await process(token.parse(txt), fn, ths));
};
entity.process = process;
module.exports = entity;