using System;
using System.Numerics;
using Dalamud.Bindings.ImGui;
using Dalamud.Configuration;
using Dalamud.Game.ClientState.Conditions;
using Dalamud.IoC;
using Dalamud.Plugin;
using Dalamud.Plugin.Services;
using FFXIVClientStructs.FFXIV.Client.Game.Event;
using FFXIVClientStructs.FFXIV.Client.System.String;
using FFXIVClientStructs.FFXIV.Client.UI;

namespace AutoFishingStool;

public sealed unsafe class Plugin : IDalamudPlugin
{
    private enum PostureAction
    {
        None,
        Sit,
        Stand,
    }

    private const int SitDelayMilliseconds = 2500;
    private const int ActionSettleMilliseconds = 500;
    private const uint FisherClassJobId = 18;

    [PluginService]
    internal static IDalamudPluginInterface PluginInterface { get; private set; } = null!;

    [PluginService]
    internal static ICondition Condition { get; private set; } = null!;

    [PluginService]
    internal static IFramework Framework { get; private set; } = null!;

    [PluginService]
    internal static IPlayerState PlayerState { get; private set; } = null!;

    [PluginService]
    internal static IPluginLog Log { get; private set; } = null!;

    private readonly Configuration configuration;
    private DateTime? postureAt;
    private PostureAction pendingPosture;
    private bool satByPlugin;
    private bool stoodForSpectral;
    private bool spectralCurrentActive;
    private bool waitingForActionToFinish;
    private bool configWindowOpen;

    public Plugin()
    {
        configuration = PluginInterface.GetPluginConfig() as Configuration ?? new Configuration();
        spectralCurrentActive = IsSpectralCurrentActive();

        Condition.ConditionChange += OnConditionChange;
        Framework.Update += OnFrameworkUpdate;
        PluginInterface.UiBuilder.Draw += DrawConfigWindow;
        PluginInterface.UiBuilder.OpenConfigUi += OpenConfigWindow;
        PluginInterface.UiBuilder.OpenMainUi += OpenConfigWindow;
        Log.Information("Auto Fishing Stool loaded");
    }

    private void OnConditionChange(ConditionFlag flag, bool value)
    {
        if (flag == ConditionFlag.Fishing)
        {
            Log.Information("Fishing condition changed to {Value}", value);

            if (value && Condition[ConditionFlag.Gathering] && IsFisher() && !satByPlugin && !ShouldStandForSpectral())
            {
                SchedulePosture(PostureAction.Sit, SitDelayMilliseconds);
                Log.Information("Fishing became active; stable Sit timer started");
            }
            else if (!value && !satByPlugin)
            {
                CancelPendingPosture();
                Log.Information("Fishing became inactive; stable Sit timer reset");
            }

            return;
        }

        if (flag != ConditionFlag.Gathering)
            return;

        Log.Information("Gathering condition changed to {Value}", value);

        if (value)
        {
            if (!IsFisher())
                return;

            satByPlugin = false;
            stoodForSpectral = false;
            CancelPendingPosture();
            Log.Information("Fisher gathering session started");
            return;
        }

        satByPlugin = false;
        stoodForSpectral = false;
        CancelPendingPosture();
    }

    private void OnFrameworkUpdate(IFramework framework)
    {
        UpdateSpectralCurrentState();

        if (pendingPosture == PostureAction.None || postureAt is null)
            return;

        if (!Condition[ConditionFlag.Gathering] || !Condition[ConditionFlag.Fishing] || !IsFisher())
        {
            CancelPendingPosture();
            return;
        }

        if (pendingPosture == PostureAction.Sit && ShouldStandForSpectral())
        {
            CancelPendingPosture();
            return;
        }

        if (pendingPosture == PostureAction.Stand && !ShouldStandForSpectral())
        {
            CancelPendingPosture();
            return;
        }

        if (DateTime.UtcNow < postureAt.Value)
            return;

        if (Condition[ConditionFlag.ExecutingGatheringAction])
        {
            if (!waitingForActionToFinish)
            {
                waitingForActionToFinish = true;
                Log.Information("Sit timer elapsed during a fishing action; waiting for it to finish");
            }

            return;
        }

        if (waitingForActionToFinish)
        {
            waitingForActionToFinish = false;
            postureAt = DateTime.UtcNow.AddMilliseconds(ActionSettleMilliseconds);
            Log.Information("Fishing action finished; posture command scheduled after settling");
            return;
        }

        var completedPosture = pendingPosture;

        var uiModule = UIModule.Instance();
        if (uiModule is null)
        {
            Log.Warning("Could not access the game's UI module");
            CancelPendingPosture();
            return;
        }

        var command = Utf8String.FromString("/sit");
        try
        {
            uiModule->ProcessChatBoxEntry(command);
            Log.Information("Submitted /sit to {Posture}", completedPosture);
        }
        finally
        {
            command->Dtor(true);
        }

        if (completedPosture == PostureAction.Sit)
        {
            satByPlugin = true;
            stoodForSpectral = false;
        }
        else
        {
            satByPlugin = false;
            stoodForSpectral = true;
        }

        CancelPendingPosture();
    }

    private void UpdateSpectralCurrentState()
    {
        var active = IsSpectralCurrentActive();
        if (active == spectralCurrentActive)
            return;

        spectralCurrentActive = active;
        Log.Information("Spectral Current changed to {Value}", active);

        if (!configuration.StandDuringSpectralCurrents)
            return;

        if (active)
        {
            if (pendingPosture == PostureAction.Sit)
                CancelPendingPosture();

            if (satByPlugin)
                SchedulePosture(PostureAction.Stand, 0);

            return;
        }

        if (stoodForSpectral && Condition[ConditionFlag.Gathering] && Condition[ConditionFlag.Fishing] && IsFisher())
            SchedulePosture(PostureAction.Sit, ActionSettleMilliseconds);
    }

    private static bool IsSpectralCurrentActive()
    {
        try
        {
            var eventFramework = EventFramework.Instance();
            var oceanFishing = eventFramework is null ? null : eventFramework->GetInstanceContentOceanFishing();
            return oceanFishing is not null && oceanFishing->SpectralCurrentActive;
        }
        catch (Exception exception)
        {
            Log.Warning(exception, "Could not read Ocean Fishing state");
            return false;
        }
    }

    private bool ShouldStandForSpectral()
    {
        return configuration.StandDuringSpectralCurrents && spectralCurrentActive;
    }

    private void SchedulePosture(PostureAction posture, int delayMilliseconds)
    {
        pendingPosture = posture;
        postureAt = DateTime.UtcNow.AddMilliseconds(delayMilliseconds);
        waitingForActionToFinish = false;
    }

    private void CancelPendingPosture()
    {
        pendingPosture = PostureAction.None;
        postureAt = null;
        waitingForActionToFinish = false;
    }

    private void OpenConfigWindow()
    {
        configWindowOpen = true;
    }

    private void DrawConfigWindow()
    {
        if (!configWindowOpen)
            return;

        ImGui.SetNextWindowSize(new Vector2(430, 0), ImGuiCond.FirstUseEver);
        if (!ImGui.Begin("Auto Fishing Stool Settings###AutoFishingStoolSettings", ref configWindowOpen, ImGuiWindowFlags.AlwaysAutoResize))
        {
            ImGui.End();
            return;
        }

        var standDuringSpectralCurrents = configuration.StandDuringSpectralCurrents;
        if (ImGui.Checkbox("Stand during Spectral Currents", ref standDuringSpectralCurrents))
        {
            configuration.StandDuringSpectralCurrents = standDuringSpectralCurrents;
            PluginInterface.SavePluginConfig(configuration);
            ApplySpectralSettingChange();
        }

        ImGui.TextWrapped("Stand while a Spectral Current is active, then sit again when it ends.");
        ImGui.Separator();
        ImGui.Text($"Spectral Current detected: {(spectralCurrentActive ? "Yes" : "No")}");
        ImGui.End();
    }

    private void ApplySpectralSettingChange()
    {
        if (!spectralCurrentActive)
            return;

        if (configuration.StandDuringSpectralCurrents)
        {
            if (pendingPosture == PostureAction.Sit)
                CancelPendingPosture();

            if (satByPlugin)
                SchedulePosture(PostureAction.Stand, 0);

            return;
        }

        if (pendingPosture == PostureAction.Stand)
            CancelPendingPosture();

        if (stoodForSpectral && Condition[ConditionFlag.Gathering] && Condition[ConditionFlag.Fishing] && IsFisher())
            SchedulePosture(PostureAction.Sit, ActionSettleMilliseconds);
    }

    private static bool IsFisher()
    {
        return PlayerState.IsLoaded && PlayerState.ClassJob.RowId == FisherClassJobId;
    }

    public void Dispose()
    {
        Condition.ConditionChange -= OnConditionChange;
        Framework.Update -= OnFrameworkUpdate;
        PluginInterface.UiBuilder.Draw -= DrawConfigWindow;
        PluginInterface.UiBuilder.OpenConfigUi -= OpenConfigWindow;
        PluginInterface.UiBuilder.OpenMainUi -= OpenConfigWindow;
    }
}