using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Dapper;
using Wabbajack.DTOs;
using Wabbajack.DTOs.DownloadStates;
using Wabbajack.Hashing.xxHash64;
using Wabbajack.Server.DTOs;

namespace Wabbajack.Server.DataLayer;

public partial class SqlService
{
    public async Task<Guid> AddKnownDownload(Archive a, DateTime downloadFinished)
    {
        await using var conn = await Open();
        var Id = Guid.NewGuid();
        await conn.ExecuteAsync(
            "INSERT INTO ArchiveDownloads (Id, PrimaryKeyString, Size, Hash, DownloadState, Downloader, DownloadFinished, IsFailed) VALUES (@Id, @PrimaryKeyString, @Size, @Hash, @DownloadState, @Downloader, @DownloadFinished, @IsFailed)",
            new
            {
                Id,
                a.State.PrimaryKeyString,
                Size = a.Size == 0 ? null : (long?) a.Size,
                Hash = a.Hash == default ? null : (Hash?) a.Hash,
                DownloadState = a.State,
                Downloader = a.State.GetType().ToString(),
                DownloadFinished = downloadFinished,
                IsFailed = false
            });
        return Id;
    }

    public async Task<Guid> EnqueueDownload(Archive a)
    {
        await using var conn = await Open();
        var Id = Guid.NewGuid();
        await conn.ExecuteAsync(
            "INSERT INTO ArchiveDownloads (Id, PrimaryKeyString, Size, Hash, DownloadState, Downloader) VALUES (@Id, @PrimaryKeyString, @Size, @Hash, @DownloadState, @Downloader)",
            new
            {
                Id,
                a.State.PrimaryKeyString,
                Size = a.Size == 0 ? null : (long?) a.Size,
                Hash = a.Hash == default ? null : (Hash?) a.Hash,
                DownloadState = a.State,
                Downloader = a.State.GetType().ToString()
            });
        return Id;
    }

    public async Task<HashSet<(Hash Hash, string PrimaryKeyString)>> GetAllArchiveDownloads()
    {
        await using var conn = await Open();
        return (await conn.QueryAsync<(Hash, string)>("SELECT Hash, PrimaryKeyString FROM ArchiveDownloads"))
            .ToHashSet();
    }

    public async Task<HashSet<(Hash Hash, IDownloadState State)>> GetAllArchiveDownloadStates()
    {
        await using var conn = await Open();
        return (await conn.QueryAsync<(Hash, IDownloadState)>("SELECT Hash, DownloadState FROM ArchiveDownloads"))
            .ToHashSet();
    }


    public async Task<ArchiveDownload> GetArchiveDownload(Guid id)
    {
        await using var conn = await Open();
        var result = await conn.QueryFirstOrDefaultAsync<(Guid, long?, Hash?, bool?, IDownloadState, DateTime?)>(
            "SELECT Id, Size, Hash, IsFailed, DownloadState, DownloadFinished FROM dbo.ArchiveDownloads WHERE Id = @id",
            new {Id = id});
        if (result == default)
            return null;

        return new ArchiveDownload
        {
            Id = result.Item1,
            IsFailed = result.Item4,
            DownloadFinished = result.Item6,
            Archive = new Archive {State = result.Item5, Size = result.Item2 ?? 0, Hash = result.Item3 ?? default}
        };
    }

    public async Task<ArchiveDownload> GetArchiveDownload(string primaryKeyString)
    {
        await using var conn = await Open();
        var result = await conn.QueryFirstOrDefaultAsync<(Guid, long?, Hash?, bool?, IDownloadState, DateTime?)>(
            "SELECT Id, Size, Hash, IsFailed, DownloadState, DownloadFinished FROM dbo.ArchiveDownloads WHERE PrimaryKeyString = @PrimaryKeyString AND IsFailed = 0",
            new {PrimaryKeyString = primaryKeyString});
        if (result == default)
            return null;

        return new ArchiveDownload
        {
            Id = result.Item1,
            IsFailed = result.Item4,
            DownloadFinished = result.Item6,
            Archive = new Archive {State = result.Item5, Size = result.Item2 ?? 0, Hash = result.Item3 ?? default}
        };
    }

    public async Task<ArchiveDownload> GetArchiveDownload(string primaryKeyString, Hash hash, long size)
    {
        await using var conn = await Open();
        var result = await conn.QueryFirstOrDefaultAsync<(Guid, long?, Hash?, bool?, IDownloadState, DateTime?)>(
            "SELECT Id, Size, Hash, IsFailed, DownloadState, DownloadFinished FROM dbo.ArchiveDownloads WHERE PrimaryKeyString = @PrimaryKeyString AND Hash = @Hash AND Size = @Size",
            new
            {
                PrimaryKeyString = primaryKeyString,
                Hash = hash,
                Size = size
            });
        if (result == default)
            return null;

        return new ArchiveDownload
        {
            Id = result.Item1,
            IsFailed = result.Item4,
            DownloadFinished = result.Item6,
            Archive = new Archive {State = result.Item5, Size = result.Item2 ?? 0, Hash = result.Item3 ?? default}
        };
    }


    public async Task<ArchiveDownload> GetOrEnqueueArchive(Archive a)
    {
        await using var conn = await Open();
        await using var trans = await conn.BeginTransactionAsync();
        var result = await conn.QueryFirstOrDefaultAsync<(Guid, long?, Hash?, bool?, IDownloadState, DateTime?)>(
            "SELECT Id, Size, Hash, IsFailed, DownloadState, DownloadFinished FROM dbo.ArchiveDownloads WHERE PrimaryKeyString = @PrimaryKeyString AND Hash = @Hash AND Size = @Size",
            new
            {
                a.State.PrimaryKeyString,
                a.Hash,
                a.Size
            }, trans);
        if (result.Item1 != default)
            return new ArchiveDownload
            {
                Id = result.Item1,
                IsFailed = result.Item4,
                DownloadFinished = result.Item6,
                Archive = new Archive {State = result.Item5, Size = result.Item2 ?? 0, Hash = result.Item3 ?? default}
            };

        var id = Guid.NewGuid();
        await conn.ExecuteAsync(
            "INSERT INTO ArchiveDownloads (Id, PrimaryKeyString, Size, Hash, DownloadState, Downloader) VALUES (@Id, @PrimaryKeyString, @Size, @Hash, @DownloadState, @Downloader)",
            new
            {
                Id = id,
                a.State.PrimaryKeyString,
                Size = a.Size == 0 ? null : (long?) a.Size,
                Hash = a.Hash == default ? null : (Hash?) a.Hash,
                DownloadState = a.State,
                Downloader = ""
            }, trans);

        await trans.CommitAsync();

        return new ArchiveDownload {Id = id, Archive = a};
    }

    public async Task<ArchiveDownload> GetNextPendingDownload(bool ignoreNexus = false)
    {
        await using var conn = await Open();
        (Guid, long?, Hash?, IDownloadState) result;

        if (ignoreNexus)
            result = await conn.QueryFirstOrDefaultAsync<(Guid, long?, Hash?, IDownloadState)>(
                "SELECT TOP(1) Id, Size, Hash, DownloadState FROM dbo.ArchiveDownloads WHERE DownloadFinished is NULL AND Downloader != 'NexusDownloader+State'");
        else
            result = await conn.QueryFirstOrDefaultAsync<(Guid, long?, Hash?, IDownloadState)>(
                "SELECT TOP(1) Id, Size, Hash, DownloadState FROM dbo.ArchiveDownloads WHERE DownloadFinished is NULL");

        if (result == default)
            return null;

        return new ArchiveDownload
        {
            Id = result.Item1,
            Archive = new Archive {State = result.Item4, Size = result.Item2 ?? 0, Hash = result.Item3 ?? default}
        };
    }

    public async Task UpdatePendingDownload(ArchiveDownload ad)
    {
        await using var conn = await Open();
        await conn.ExecuteAsync(
            "UPDATE dbo.ArchiveDownloads SET IsFailed = @IsFailed, DownloadFinished = @DownloadFinished, Hash = @Hash, Size = @Size, FailMessage = @FailMessage WHERE Id = @Id",
            new
            {
                ad.Id,
                ad.IsFailed,
                ad.DownloadFinished,
                ad.Archive.Size,
                ad.Archive.Hash,
                ad.FailMessage
            });
    }

    public async Task<int> EnqueueModListFilesForIndexing()
    {
        await using var conn = await Open();
        return await conn.ExecuteAsync(@"
            INSERT INTO dbo.ArchiveDownloads (Id, PrimaryKeyString, Hash, DownloadState, Size, Downloader)
            SELECT DISTINCT NEWID(), mla.PrimaryKeyString, mla.Hash, mla.State, mla.Size, SUBSTRING(mla.PrimaryKeyString, 0, CHARINDEX('|', mla.PrimaryKeyString))
            FROM [dbo].[ModListArchives] mla
                LEFT JOIN dbo.ArchiveDownloads ad on mla.PrimaryKeyString = ad.PrimaryKeyString AND mla.Hash = ad.Hash
            WHERE ad.PrimaryKeyString is null");
    }

    public async Task<List<Archive>> GetGameFiles(Game game, string version)
    {
        await using var conn = await Open();
        var files = (await conn.QueryAsync<(Hash, long, IDownloadState)>(
                $"SELECT Hash, Size, DownloadState FROM dbo.ArchiveDownloads WHERE PrimaryKeyString like 'GameFileSourceDownloader+State|{game}|{version}|%'"))
            .Select(f => new Archive
            {
                State = f.Item3,
                Hash = f.Item1,
                Size = f.Item2
            }).ToList();
        return files;
    }

    public async Task<Archive[]> ResolveDownloadStatesByHash(Hash hash)
    {
        await using var conn = await Open();
        var files = (await conn.QueryAsync<(long, Hash, IDownloadState)>(
                @"SELECT Size, Hash,  DownloadState from dbo.ArchiveDownloads WHERE Hash = @Hash AND IsFailed = 0 AND DownloadFinished IS NOT NULL ORDER BY DownloadFinished DESC",
                new {Hash = hash})
            ).Select(e =>
                new Archive {State = e.Item3, Size = e.Item1, Hash = e.Item2}
            ).ToList();

        if (await HaveMirror(hash) && files.Count > 0)
        {
            var ffile = files.First();
            var host = _settings.TestMode ? "test-files" : "mirror";
            var url = new Uri($"https://{host}.wabbajack.org/{hash.ToHex()}");
            files.Add(new Archive
                {State = new WabbajackCDN {Url = url}, Hash = hash, Size = ffile.Size, Name = ffile.Name});
        }

        return files.ToArray();
    }

    public async Task<IEnumerable<(Game, string)>> GetAllRegisteredGames()
    {
        await using var conn = await Open();
        var pks = await conn.QueryAsync<string>(
            @"SELECT PrimaryKeyString FROM dbo.ArchiveDownloads WHERE PrimaryKeyString like 'GameFileSourceDownloader+State|%'");
        return pks.Select(p => p.Split("|"))
            .Select(t => (GameRegistry.GetByFuzzyName(t[1]).Game, t[2]))
            .Distinct();
    }
}