//  Created by xudong wu on 02/03/2017.
//  Copyright © 2017 wuxudong. All rights reserved.
//

import Foundation
import DGCharts
import SwiftyJSON

open class DataExtract {
    func extract(_ data: JSON) -> ChartData?  {
        if data["dataSets"].array == nil {
            return nil;
        }

        let chartData = createData();


        let dataSets = data["dataSets"].arrayValue;

        for (_, dataSet) in dataSets.enumerated() {

            let values = dataSet["values"].arrayValue;
            let label = dataSet["label"].stringValue;

            if values != nil && label != nil {
                let entries = createEntries(values);

                let chartDataSet = createDataSet(entries, label: label);

                if dataSet["config"].dictionary != nil {
                    dataSetConfig(chartDataSet, config: dataSet["config"])
                }

                chartData.append(chartDataSet);
            }
        }

        if data["config"].dictionary != nil {
            dataConfig(chartData, config: data["config"])
        }


        return chartData

    }

    func createEntries(_ values: [JSON]) -> [ChartDataEntry] {
        var entries = [ChartDataEntry]();

        for (index, value) in values.enumerated() {
            if value.null == nil {
                entries.append(createEntry(values, index: index))
            }
        }

        return entries;

    }


    func createData() -> ChartData {
        fatalError("subclass should override this function")
    }

    func dataConfig(_ data: ChartData, config: JSON) {}

    func createDataSet(_ entries: [ChartDataEntry], label: String) -> ChartDataSetProtocol {
        fatalError("subclass should override this function")
    }

    func dataSetConfig(_ dataSet: ChartDataSetProtocol, config: JSON) {
        fatalError("subclass should override this function")
    }

    func createEntry(_ values: [JSON], index: Int) -> ChartDataEntry {
        fatalError("subclass should override this function")
    }


}