using System.Reflection.PortableExecutable;
using Splat;
using StarsAssistant.Model;

namespace StarsAssistant.Services;

public class Game
{
    /// <summary>
    /// Default constructor, initialize required fields manually, targeted
    /// for Initial DB creation.
    /// </summary>
    public Game() {}

    /// <summary>
    /// Init game state from database, targeted for CLI arg.
    /// </summary>
    /// <param name="dbGame">Record loaded from DB</param>
    public Game(Model.Game dbGame)
    {
        GamePath = dbGame.GamePath;
        BaseName = dbGame.BaseName;
    }

    /// <summary>
    /// Helper to construct the game from a command line.
    /// </summary>
    /// <param name="args">The command line to parse.</param>
    public Game(string[]? args)
    {
        GamePath = "/home/torben/Nextcloud/Documents/Stars!/Games/goingth/";
        BaseName = "GOINGTH";
        string dbPath = DatabaseFileName;

        using StarsDatabase starsDB = new(dbPath);
        if (Path.Exists(dbPath))
        {
            Model.Game dbGame = starsDB.Game.First();
        }
        else
        {
            starsDB.Database.EnsureCreated();
            SaveToDatabase(starsDB);
            __doCreateTestData = true;
        }
    }
    
    /// <summary>
    /// The base path in which all game files reside.
    /// </summary>
    public string GamePath { get; set; } = String.Empty;

    /// <summary>
    /// The base name without extensions of your game, inside the GamePath folder.
    /// All dependant files are resolved using this name.
    /// </summary>
    public string BaseName { get; set; } = String.Empty;

    /// <summary>
    /// Combine into the DatabaseName
    /// </summary>
    public string DatabaseFileName => Path.Combine(GamePath, $"{BaseName}.sqlite");

    /// <summary>
    /// Search for Planet files using this pattern, will give you all pxx files.
    /// </summary>
    public string PlanetFileSearchPattern => $"{BaseName}.p*";
    
    /// <summary>
    /// Internal helper to lazily load the current player from the DB.
    /// </summary>
    private readonly static Lazy<Race>LazyPlayer = new ( () => {
        using var db = Locator.Current.GetService<StarsDatabase>()!;
        Race result = db.Race
            .Where(r => r.PlayerRace == true)
            .First();
        return result;
    });

    /// <summary>
    /// Get the Race object for the current player, lazy initialized.
    /// </summary>
    public static Race Player => LazyPlayer.Value;

    /// <summary>
    /// Get the name of a planet file for a given race.
    /// </summary>
    /// <param name="r">The race to load.</param>
    /// <returns>Fully qualified file path.</returns>
    public string PlanetFileForRace (Race r) => Path.Combine(GamePath, $"{BaseName}.p{r.PlayerFileId}");

    /// <summary>
    /// Save this record in the database. Uses the service locator to access the 
    /// database unless you specify an instance. This is needed during initial
    /// game creation, where the services are not yet established.
    /// </summary>
    /// <param name="db">Optional DB instance if services are yet unavailable.</param>
    public void SaveToDatabase(StarsDatabase? db = null) 
    {
        db ??= Locator.Current.GetService<StarsDatabase>()!;
        
        Model.Game? dbGame = db.Game.FirstOrDefault();
        if (dbGame == null)
        {
            dbGame = new Model.Game();
            db.Add(dbGame);
            db.SaveChanges();
        }
        dbGame.GamePath = GamePath;
        dbGame.BaseName = BaseName; 
        db.Update(dbGame);
        db.SaveChanges();
    }

    /// <summary>
    /// Registers all services depending on this Game, in the order required.
    /// This is called once the framework is initialized but before the main 
    /// window is active and has its models.
    /// </summary>
    public void RegisterServicesForGame()
    {
        Locator.CurrentMutable.RegisterConstant(this, typeof(Services.Game));
        Locator.CurrentMutable.RegisterConstant(new CSVDataLoader(), typeof(CSVDataLoader));
        Locator.CurrentMutable.Register(() => new StarsDatabase(DatabaseFileName), typeof(StarsDatabase));

        // TESTING HELPER
        if (__doCreateTestData)
            __createTestData();
    }

    /// <summary>
    /// Starts all required background servies, so that we are in normal UI
    /// operation mode. This is called after the UI is up and running.
    /// </summary>
    public void StartBackgroundServices()
    {
        CSVDataLoader csvloader = Locator.Current.GetService<Services.CSVDataLoader>()!;
        csvloader.StartCSVWatcher();
    }


    private bool __doCreateTestData = false;

    /// <summary>
    /// TESTING HELPER
    /// </summary>
    private void __createTestData ()
    {
        using var db = Locator.Current.GetService<StarsDatabase>()!;

        // Note: This sample requires the database to be created before running.
        // Console.WriteLine($"Database path: {db.DbPath}.");

        Race r = new()
        {
            Name = "Atlantis",
            PlayerRace = true,
            PlayerFileId = 1,
            ColonistsPerResource = 1000,
            GrowthRatePercent = 19,
            PRT = PRT.Other,
            HasOBRM = true,
            FactoryCost3 = false,
            FactoryNumberPer10k = 8,
            FactoryResCost = 8,
            FactoryResPer10 = 15,
            MineResCost = 3,
            MineMineralsPer10 = 10,
            MineNumberPer10k = 10
        };
        db.Add(r);
        db.SaveChanges();

        var loader = new CSV.PlanetLoader();
        loader.ImportForRace(Services.Game.Player);
    }

}