//
//  CSVUtils.swift
//  TournamentStats
//
//  Created by Laurent Morvillier on 03/06/2019.
//  Copyright © 2019 Stax River. All rights reserved.
//

import Foundation
import Charts

extension UIColor {
    
    static var paGreen: UIColor {
        return UIColor(red: 0/255, green: 255/255, blue: 196/255, alpha: 1)
    }
    
    static var paColor1: UIColor {
        return UIColor(red: 125/255, green: 155/255, blue: 255/255, alpha: 1)
    }
    
    static var paColor2: UIColor {
        return UIColor(red: 255/255, green: 125/255, blue: 196/255, alpha: 1)
    }

}

struct ColumnDescriptor {
    var header: String
    var number: Bool = false
    var widthWeight: CGFloat = 1.0
}

protocol ColumnRepresentable {
    static func columnDescriptors() -> [ColumnDescriptor]
    func cellValues() -> [String]
    var chartDataEntry: ChartDataEntry { get }
    var pieChartDataEntry: PieChartDataEntry { get }
}

extension ColumnRepresentable {
    var chartDataEntry: ChartDataEntry {
        return ChartDataEntry(x: 0, y: 0)
    }
    var pieChartDataEntry: PieChartDataEntry {
        return PieChartDataEntry(value: 0.0)
    }
}

class PercentageFormatter : IValueFormatter {
    
    var numberFormatter: NumberFormatter = NumberFormatter()
    
    init() {
        self.numberFormatter.maximumFractionDigits = 0
    }
    
    func stringForValue(_ value: Double, entry: ChartDataEntry, dataSetIndex: Int, viewPortHandler: ViewPortHandler?) -> String {
        return self.numberFormatter.string(from: NSNumber(value: value)) ?? ""
    }
    
}

extension Array where Element : ColumnRepresentable {
    
    var pieChartData: PieChartData {
        var dataEntries: [ChartDataEntry] = []
        self.forEach { representable in
            dataEntries.append(representable.pieChartDataEntry)
        }
        let dataSet = PieChartDataSet(entries: dataEntries, label: "")
        dataSet.entryLabelFont = UIFont.boldSystemFont(ofSize: 18.0)
        dataSet.colors = [UIColor.paGreen, UIColor.paColor1, UIColor.paColor2]
        dataSet.valueFormatter = PercentageFormatter()
        return PieChartData(dataSet: dataSet)
    }
    
    var chartData: ChartData {
        var dataEntries: [ChartDataEntry] = []
        self.forEach { representable in
            dataEntries.append(representable.chartDataEntry)
        }
        let dataSet = ChartDataSet(entries: dataEntries)
        return ChartData(dataSet: dataSet)
    }
    
}

protocol HTMLRepresentable : ColumnRepresentable {
    static func htmlHeaders() -> String
    func html() -> String
}

extension HTMLRepresentable {
    
    static func htmlHeaders() -> String {
        let all = self.columnDescriptors().map { $0.header }.joined(separator: "</td><td>")
        return "<tr class=\"table-header\"><td>\(all)</td></tr>"
    }
    
    func html() -> String {
        let all = self.cellValues().joined(separator: "</td><td>")
        return "<tr><td>\(all)</td></tr>"
    }
    
}

extension Array where Element : HTMLRepresentable {
    
    func writeHTML(fileName: String, limit: Int? = 10) {
        
        var html = "<table class=\"wp-block-table alignwide\">\n"
        html.append("<thead>")
        html.append(Element.htmlHeaders())
        html.append("</thead>\n<tbody>")
        let max = limit ?? Int.max
        for (index, rep) in self.enumerated() {
            html.append("\n")
            html.append(rep.html())
            
            if index + 1 >= max {
                break
            }
        }
        html.append("\n</tbody></table>")
        
        do {
            try FileWriter.writeToDocumentDirectory(content: html, fileName: fileName)
        } catch {
            print(error)
        }
        
    }
    
}


extension Array where Element : CSVRepresentable {
    
    func writeCSV(file: String, limit: Int? = 10) {
        
        var string = Element.csvHeaders()
        let max = limit ?? Int.max
        for (index, rep) in self.enumerated() {
            string.append("/n")
            string.append(rep.csv())
            
            if index >= max {
                break
            }
        }
        
        do {
            try FileWriter.writeToDocumentDirectory(content: string, fileName: file)
        } catch {
            print(error)
        }
        
    }
    
}

public protocol CSVRepresentable {
    static func csvHeaders() -> String
    func csv() -> String
}