var _curry1 = require('./internal/_curry1');
var apply = require('./apply');
var curryN = require('./curryN');
var map = require('./map');
var max = require('./max');
var pluck = require('./pluck');
var reduce = require('./reduce');
var values = require('./values');


/**
 * Given a spec object recursively mapping properties to functions, creates a
 * function producing an object of the same structure, by mapping each property
 * to the result of calling its associated function with the supplied arguments.
 *
 * @func
 * @memberOf R
 * @since v0.20.0
 * @category Function
 * @sig {k: ((a, b, ..., m) -> v)} -> ((a, b, ..., m) -> {k: v})
 * @param {Object} spec an object recursively mapping properties to functions for
 *        producing the values for these properties.
 * @return {Function} A function that returns an object of the same structure
 * as `spec', with each property set to the value returned by calling its
 * associated function with the supplied arguments.
 * @see R.converge, R.juxt
 * @example
 *
 *      var getMetrics = R.applySpec({
 *                                      sum: R.add,
 *                                      nested: { mul: R.multiply }
 *                                   });
 *      getMetrics(2, 4); // => { sum: 6, nested: { mul: 8 } }
 * @symb R.applySpec({ x: f, y: { z: g } })(a, b) = { x: f(a, b), y: { z: g(a, b) } }
 */
module.exports = _curry1(function applySpec(spec) {
  spec = map(function(v) { return typeof v == 'function' ? v : applySpec(v); },
             spec);
  return curryN(reduce(max, 0, pluck('length', values(spec))),
                function() {
                  var args = arguments;
                  return map(function(f) { return apply(f, args); }, spec);
                });
});