global using System;
using System.Collections.Concurrent;
using System.IO;
using System.Linq;
using System.Net;
using System.Text.Json;
using System.Text.Json.Serialization;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;
using ParadoxSaveParser.Lib;

namespace ParadoxSaveParser.WebAPI;

public enum SaveFileProcessingStatus
{
    NotFound, Uploading, Parsing, SavingResults, Done, Error
}

public class SaveFileMetadata
{
    public required string guid;
    public required SaveFileProcessingStatus status { get; set; }
}

public class Program
{
    private const string DATA_DIR = "data";
    private static string SAVES_DIR = Path.Join(DATA_DIR, "saves");
    private static ConcurrentDictionary<string, SaveFileMetadata> _saveMetadataStorage = new();
    
    public static void Main(string[] args)
    {
        var builder = WebApplication.CreateBuilder(args);
        var app = builder.Build();

        foreach (var metaFilePath in Directory.GetFiles(SAVES_DIR, "*.meta.json", SearchOption.TopDirectoryOnly))
        {
            using var metaFile = File.Open(metaFilePath, FileMode.Open, FileAccess.Read);
            var meta = JsonSerializer.Deserialize<SaveFileMetadata>(metaFile) ?? throw new NullReferenceException(metaFilePath);
            if (meta.status != SaveFileProcessingStatus.Done)
            {
                app.Logger.Log(LogLevel.Warning, $"metadata file '{metaFilePath}' status has invalid status {meta.status}"));
            }

            if(!_saveMetadataStorage.TryAdd(meta.guid, meta))
                throw new Exception("Guid collision!");
        }
        
        app.UseHttpsRedirection();
        app.MapPost("/parse/eu4", async httpContext =>
        {
            var remoteFile = httpContext.Request.Form.Files.FirstOrDefault();
            if(remoteFile is null)
                return;
            string save_id = Guid.NewGuid().ToString();
            string meta_file_path = Path.Join(SAVES_DIR, save_id + ".meta.json");
            // string save_file_path = Path.Join(SAVES_DIR, save_id + ".eu4");
            // await using var metaFile = File.Open(meta_file_path, FileMode.CreateNew, FileAccess.Write);
            if (File.Exists(meta_file_path))
            {
                httpContext.Response.StatusCode = StatusCodes.Status500InternalServerError;
                throw new Exception($"Guid collision! file {meta_file_path} already exists.")
            }

            await using var saveFile = 
            await remoteFile.OpenReadStream().CopyToAsync();
            var parser = new ParserEU4(stream);
            
            
        });
        
        app.Run();
    }
}