'use strict';

// Process ^superscript^

// same as UNESCAPE_MD_RE plus a space
const UNESCAPE_RE = /\\([ \\!"#$%&'()*+,./:;<=>?@[\]^_`{|}~-])/g;
function superscript(state, silent) {
  const max = state.posMax;
  const start = state.pos;
  if (state.src.charCodeAt(start) !== 0x5E /* ^ */) {
    return false;
  }
  if (silent) {
    return false;
  } // don't run any pairs in validation mode
  if (start + 2 >= max) {
    return false;
  }
  state.pos = start + 1;
  let found = false;
  while (state.pos < max) {
    if (state.src.charCodeAt(state.pos) === 0x5E /* ^ */) {
      found = true;
      break;
    }
    state.md.inline.skipToken(state);
  }
  if (!found || start + 1 === state.pos) {
    state.pos = start;
    return false;
  }
  const content = state.src.slice(start + 1, state.pos);

  // don't allow unescaped spaces/newlines inside
  if (content.match(/(^|[^\\])(\\\\)*\s/)) {
    state.pos = start;
    return false;
  }

  // found!
  state.posMax = state.pos;
  state.pos = start + 1;

  // Earlier we checked !silent, but this implementation does not need it
  const token_so = state.push('sup_open', 'sup', 1);
  token_so.markup = '^';
  const token_t = state.push('text', '', 0);
  token_t.content = content.replace(UNESCAPE_RE, '$1');
  const token_sc = state.push('sup_close', 'sup', -1);
  token_sc.markup = '^';
  state.pos = state.posMax + 1;
  state.posMax = max;
  return true;
}
function sup_plugin(md) {
  md.inline.ruler.after('emphasis', 'sup', superscript);
}

module.exports = sup_plugin;