import { DefinedInfo } from './util/defined-info.mjs';
import { Info } from './util/info.mjs';
import { normalize } from './normalize.mjs';

/**
 * @import {Schema} from 'property-information'
 */


const cap = /[A-Z]/g;
const dash = /-[a-z]/g;
const valid = /^data[-\w.:]+$/i;

/**
 * Look up info on a property.
 *
 * In most cases the given `schema` contains info on the property.
 * All standard,
 * most legacy,
 * and some non-standard properties are supported.
 * For these cases,
 * the returned `Info` has hints about the value of the property.
 *
 * `name` can also be a valid data attribute or property,
 * in which case an `Info` object with the correctly cased `attribute` and
 * `property` is returned.
 *
 * `name` can be an unknown attribute,
 * in which case an `Info` object with `attribute` and `property` set to the
 * given name is returned.
 * It is not recommended to provide unsupported legacy or recently specced
 * properties.
 *
 *
 * @param {Schema} schema
 *   Schema;
 *   either the `html` or `svg` export.
 * @param {string} value
 *   An attribute-like or property-like name;
 *   it will be passed through `normalize` to hopefully find the correct info.
 * @returns {Info}
 *   Info.
 */
function find(schema, value) {
  const normal = normalize(value);
  let property = value;
  let Type = Info;

  if (normal in schema.normal) {
    return schema.property[schema.normal[normal]]
  }

  if (normal.length > 4 && normal.slice(0, 4) === 'data' && valid.test(value)) {
    // Attribute or property.
    if (value.charAt(4) === '-') {
      // Turn it into a property.
      const rest = value.slice(5).replace(dash, camelcase);
      property = 'data' + rest.charAt(0).toUpperCase() + rest.slice(1);
    } else {
      // Turn it into an attribute.
      const rest = value.slice(4);

      if (!dash.test(rest)) {
        let dashes = rest.replace(cap, kebab);

        if (dashes.charAt(0) !== '-') {
          dashes = '-' + dashes;
        }

        value = 'data' + dashes;
      }
    }

    Type = DefinedInfo;
  }

  return new Type(property, value)
}

/**
 * @param {string} $0
 *   Value.
 * @returns {string}
 *   Kebab.
 */
function kebab($0) {
  return '-' + $0.toLowerCase()
}

/**
 * @param {string} $0
 *   Value.
 * @returns {string}
 *   Camel.
 */
function camelcase($0) {
  return $0.charAt(1).toUpperCase()
}

export { find };
