using System.Runtime.InteropServices;
using Dalamud.Game.Text.SeStringHandling;
using Dalamud.Game.Text.SeStringHandling.Payloads;
using Dalamud.Hooking;
using Dalamud.IoC;
using Dalamud.Plugin;
using Dalamud.Plugin.Services;
using Dalamud.Utility.Signatures;
using TimePasses.Model;
using YamlDotNet.Serialization;
using YamlDotNet.Serialization.NamingConventions;

namespace TimePasses;

public class Plugin : IDalamudPlugin {
    [PluginService]
    private IGameInteropProvider GameInterop { get; init; }

    [PluginService]
    internal static IPluginLog Log { get; set; }

    private HttpClient Client { get; } = new();

    private DataFile Data { get; set; }
    private Dictionary<(string, bool), nint> ReplacementPointers { get; } = [];
    private SemaphoreSlim Mutex { get; } = new(1, 1);

    internal static IDeserializer Deserializer { get; } = new DeserializerBuilder()
        .WithNamingConvention(UnderscoredNamingConvention.Instance)
        .WithNodeDeserializer(new WhenNodeDeserialiser())
        .Build();

    private static class Signatures {
        internal const string GetBalloonRow = "E8 ?? ?? ?? ?? 48 85 C0 74 4D 48 89 5C 24";
    }

    private delegate nint GetBalloonRowDelegate(uint rowId);

    [Signature(Signatures.GetBalloonRow, DetourName = nameof(GetBalloonRowDetour))]
    private Hook<GetBalloonRowDelegate>? GetBalloonRowHook { get; init; }

    public Plugin() {
        this.GameInterop!.InitializeFromAttributes(this);
        this.GetBalloonRowHook?.Enable();

        Task.Run(async () => {
            #if DEBUG
            var stream = typeof(Plugin).Assembly.GetManifestResourceStream("TimePasses.replacements.yaml");
            using var reader = new StreamReader(stream!);
            var yaml = await reader.ReadToEndAsync();
            #else
            using var resp = await this.Client.GetAsync("https://git.anna.lgbt/anna/TimePasses/raw/branch/main/replacements.yaml");
            var yaml = await resp.Content.ReadAsStringAsync();
            #endif

            await this.Mutex.WaitAsync();
            try {
                this.Data = Plugin.Deserializer.Deserialize<DataFile>(yaml);
                this.ReplacementPointers.Clear();
            } finally {
                this.Mutex.Release();
            }
        });
    }

    public void Dispose() {
        this.GetBalloonRowHook?.Dispose();
        this.Client.Dispose();
        this.Mutex.Dispose();
        foreach (var (_, ptr) in this.ReplacementPointers) {
            Marshal.FreeHGlobal(ptr);
        }

        this.ReplacementPointers.Clear();
    }

    private nint GetBalloonRowDetour(uint rowId) {
        try {
            var ptr = this.GetBalloonRowDetourInner(rowId);
            if (ptr != null) {
                return ptr.Value;
            }
        } catch (Exception ex) {
            Plugin.Log.Error(ex, "Error in GetBalloonRowDetour");
        }

        return this.GetBalloonRowHook!.Original(rowId);
    }

    private nint? GetBalloonRowDetourInner(uint rowId) {
        this.Mutex.Wait();
        using var release = new OnDispose(() => this.Mutex.Release());

        var rep = this.Data.Replacements.FirstOrDefault(rep => rep.Id == rowId);
        if (rep == null) {
            return null;
        }

        var when = rep.When.FirstOrDefault(when => when.IsValid(this));
        if (when == null) {
            if (rep.Text != null) {
                return this.GetOrCreateReplacementPointer(rep.Text, rep.Slowly);
            }

            return null;
        }

        return this.GetOrCreateReplacementPointer(when.Text, when.Slowly);
    }

    private nint GetOrCreateReplacementPointer(string text, bool slowly) {
        if (this.ReplacementPointers.TryGetValue((text, slowly), out var cached)) {
            return cached;
        }

        var lines = text
            .ReplaceLineEndings("\n")
            .Split('\n');
        var seStringBuilder = new SeStringBuilder();
        for (var i = 0; i < lines.Length; i++) {
            if (i != 0) {
                seStringBuilder.Add(NewLinePayload.Payload);
            }

            seStringBuilder.AddText(lines[i].TrimEnd());
        }

        var textBytes = seStringBuilder.Encode();

        unsafe {
            var ptr = (uint*) Marshal.AllocHGlobal(8 + textBytes.Length + 1);
            try {
                *ptr = 8;
                *(ptr + 1) = slowly ? 1u : 0u;

                var bytes = (byte*) (ptr + 2);
                bytes[textBytes.Length] = 0;
                Marshal.Copy(textBytes, 0, (nint) bytes, textBytes.Length);

                this.ReplacementPointers![(text, slowly)] = (nint) ptr;
                return (nint) ptr;
            } catch {
                Marshal.FreeHGlobal((nint) ptr);
                throw;
            }
        }
    }
}

[Serializable]
internal class DataFile {
    public Replacement[] Replacements { get; init; }
}