scitran/core

'use strict';

var _ = require('lodash');

/**
 * Deep-walk an object, invoking callback for each property.
 * Properties will be replaced with any value returned by callback.
 * @param obj The object to walk
 * @param {function} callback The callback function, that will be invoked with:
 *   `propertyValue, path, state`
 * @param {path} The current path array (default is empty array)
 * @param {state} An optional state parameter
 */
module.exports = function objWalk(obj, callback, path, state) {
    var i, idx;
    state = state || {};

    if( path ) {
        path = path.slice()
    } else {
        path = [];
    }
    idx = path.length;

    obj = callback(obj, path, state);

    if( _.isArray(obj) ) {
        for( i = 0; i < obj.length; i++ ) {
            path[idx] = '' + i;
            obj[i] = objWalk(obj[i], callback, path, _.cloneDeep(state));
        }
    } else if( _.isObjectLike(obj) ) {
        for( i in obj ) {
            if( obj.hasOwnProperty(i) ) {
                path[idx] = i;
                obj[i] = objWalk(obj[i], callback, path, _.cloneDeep(state));
            }
        }
    }

    return obj;
}