/* eslint-disable default-case */
import { DM_DERIVATIVES } from '../constants';
/**
* iterate the children and call the callback for each
*
* @param {DataModel} datamodel
* @param {function} callback
* @param {DM_DERIVATIVES} operation
*/
function childIterator (datamodel, callback, operation) {
const children = datamodel._children;
children.forEach((child) => {
if (child._derivation
&& child._derivation.length === 1) {
switch (operation) {
case DM_DERIVATIVES.SELECT:
if (child._derivation[0].op === DM_DERIVATIVES.SELECT) {
callback(child, child._derivation[0].criteria);
}
break;
case DM_DERIVATIVES.PROJECT:
if (child._derivation[0].op === DM_DERIVATIVES.PROJECT) {
callback(child, child._derivation[0].meta.actualProjField);
}
break;
case DM_DERIVATIVES.GROUPBY:
if (child._derivation[0].op === DM_DERIVATIVES.GROUPBY) {
callback(child,
{ groupByString: child._derivation[0].meta.groupByString,
reducer: child._derivation[0].criteria });
}
break;
case DM_DERIVATIVES.CAL_VAR:
if (child._derivation[0].op === DM_DERIVATIVES.CAL_VAR) {
let params = [child._derivation[0].meta.config, [child._derivation[0].meta.fields,
child._derivation[0].criteria]];
callback(child, ...params);
}
break;
}
}
});
}
/**
* Invokes a callback for every child created by a selection operation on a DataModel.
*
* @param {DataModel} datamodel - The input DataModel instance.
* @param {Function} callback - The callback to be invoked on each child. The parameters
* provided to the callback are the child DataModel instance and the selection
* function used to create it.
*/
export function selectIterator (datamodel, callback) {
childIterator(datamodel, callback, DM_DERIVATIVES.SELECT);
}
/**
* Invokes a callback for every measure child of a DataModel.
*
* @param {DataModel} datamodel - The input DataModel instance.
* @param {Function} callback - The callback to be invoked on each measure child. The parameters
* provided to the callback are the child DataModel instance and the child params.
*/
export function calculatedVariableIterator (datamodel, callback) {
childIterator(datamodel, callback, DM_DERIVATIVES.CAL_VAR);
}
/**
* Invokes a callback for every projected child of a DataModel.
*
* @param {DataModel} datamodel - The input DataModel instance.
* @param {Function} callback - The callback to be invoked on each projected child. The parameters
* provided to the callback are the child DataModel instance and the
* projection string.
*/
export function projectIterator (datamodel, callback) {
childIterator(datamodel, callback, DM_DERIVATIVES.PROJECT);
}
/**
* Invokes a callback over the children created by a groupBy
* operation on a DataModel.
*
* @param {DataModel} datamodel - The input DataModel instance.
* @param {Function} callback - The callback to be invoked. The parameters
* provided to the callback are the child DataModel instance and the groupBy string used to create it.
*/
export function groupByIterator (datamodel, callback) {
childIterator(datamodel, callback, DM_DERIVATIVES.GROUPBY);
}