mekanika/skematic

/**
 * Import rules and type checker
 * @ignore
 */

const {isEmpty} = require('./rules')
const is = require('./is')

/**
 * Sets a default value if specified on empty fields
 *
 * Supports passing an object and complex model.
 *
 * @param {Mixed} v The value or object to default
 * @param {Model} model The associated model to check the default value on
 *
 * @returns Value or the default value
 * @memberof Format
 * @alias setDefault
*/

module.exports = function (v, model) {
  if (!model) return v

  const def = function (v, s) {
    // No default, return the value as is
    if (s.default === undefined) return v

    // Return the default if `v` is empty (ie. undefined or '')
    return isEmpty(v) || v === null ? s.default : v
  }

  // Parse objects (but NOT arrays)
  if (v && typeof v === 'object' && !Array.isArray(v)) {
    for (var k in model) {
      if (!is.undefined(model[k].default)) v[k] = def(v[k], model[k])
    }

    return v

  // Or simply return defaulted scalars
  } else return def(v, model)
}