//
//  LiquipediaMatchesAPI.swift
//  LiquipediaMenu
//
//This class scrapes the Liquipedia upcoming matches page. It extracts them and puts them into a [Match]? by, using the Match class as a data storage objet.
//  Created by Felix Förtsch on 08.10.18.
//  Copyright © 2018 Felix Förtsch. All rights reserved.
//

import Foundation
import SwiftSoup

class LiquipediaMatchesAPI {
    
    func fetchMatches(for game: String) -> [Match]? {
        let games = ["dota2", "starcraft", "starcraft2", "heroes", "counterstrike", "rocketleague", "rainbowsix", "overwatch"]
        if !games.contains(game) { return nil }
        if let data = fetchData(for: game) {
            return extractMatches(from: data)
        }
        return nil
    }
    
    private func fetchData(for game: String) -> String? {
        let url = constructURL(for: game)
        if let data = try? String(contentsOf: url) {
            return data
        }
        return nil
    }
    
    private func extractMatches(from data: String) -> [Match]? {
        var tmp = data.replacingOccurrences(of: "\\n", with: "")
        tmp = tmp.replacingOccurrences(of: "\\", with: "")
        
        do {
            let doc: Document = try SwiftSoup.parse(tmp)
            let ongoing: Element = try doc.getElementById("infobox_matches")!
            let matchString: Elements = try ongoing.getElementsByTag("table")
            
            var matches = [Match]()
            for match in matchString {
                
                let score = try match.getElementsByClass("versus").text()
                let split = score.split(separator: ":")
                let leftscore = String(split[0])
                let rightscore = String(split[1])

                let newMatch = Match()
                newMatch.ongoing = true
                // TODO: Handle what happens when there is no twitch page. Currently it just opens Twicht main page.
                newMatch.streamLink = try "https://twitch.tv/" + match.getElementsByClass("timer-object").attr("data-stream-twitch")
                newMatch.league = try match.select("tr > td > div > div > a").text()
                newMatch.team1name = try match.getElementsByClass("team-left").text()
                newMatch.team1score = leftscore
                newMatch.team2name = try match.getElementsByClass("team-right").text()
                newMatch.team2score = rightscore
                matches.append(newMatch)
            }
            if matches.count == 0 {
                return nil
            }
            return matches
        } catch Exception.Error(_, _) {
            print("")
            return nil
        } catch {
            print("")
            return nil
        }
    }
    
    private func constructURL(for game: String) -> URL {
        let baseURL = "https://liquipedia.net/"
        let query = "/api.php?action=parse&page=Liquipedia:Upcoming_and_ongoing_matches&format=json&prop=text"
        return URL(string: baseURL + game + query)!
    }
}