var VisualMapping = require("../../visual/VisualMapping");

var zrUtil = require("@okfe/zrender/lib/core/util");

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements.  See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership.  The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License.  You may obtain a copy of the License at
*
*   http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied.  See the License for the
* specific language governing permissions and limitations
* under the License.
*/

/**
 * @file Visual encoding for sankey view
 * @author  Deqing Li(annong035@gmail.com)
 */
function _default(ecModel, payload) {
  ecModel.eachSeriesByType('sankey', function (seriesModel) {
    var graph = seriesModel.getGraph();
    var nodes = graph.nodes;

    if (nodes.length) {
      var minValue = Infinity;
      var maxValue = -Infinity;
      zrUtil.each(nodes, function (node) {
        var nodeValue = node.getLayout().value;

        if (nodeValue < minValue) {
          minValue = nodeValue;
        }

        if (nodeValue > maxValue) {
          maxValue = nodeValue;
        }
      });
      zrUtil.each(nodes, function (node) {
        var mapping = new VisualMapping({
          type: 'color',
          mappingMethod: 'linear',
          dataExtent: [minValue, maxValue],
          visual: seriesModel.get('color')
        });
        var mapValueToColor = mapping.mapValueToVisual(node.getLayout().value);
        node.setVisual('color', mapValueToColor); // If set itemStyle.normal.color

        var itemModel = node.getModel();
        var customColor = itemModel.get('itemStyle.color');

        if (customColor != null) {
          node.setVisual('color', customColor);
        }
      });
    }
  });
}

module.exports = _default;