using System;
using System.Numerics;
using System.Runtime.InteropServices;
using Dalamud.Hooking;

namespace Tourist {
    public class GameFunctions : IDisposable {
        private delegate IntPtr VistaUnlockedDelegate(ushort index, int a2, int a3);

        private delegate IntPtr CreateVfxDelegate(string name);

        private delegate IntPtr PlayVfxDelegate(IntPtr vfx, float idk, int idk2);

        internal delegate IntPtr RemoveVfxDelegate(IntPtr vfx);

        private Plugin Plugin { get; }
        private IntPtr SightseeingMaskPointer { get; }

        private CreateVfxDelegate CreateVfx { get; }
        private PlayVfxDelegate PlayVfxInternal { get; }
        internal RemoveVfxDelegate RemoveVfx { get; }
        private Hook<VistaUnlockedDelegate> VistaUnlockedHook { get; }

        public GameFunctions(Plugin plugin) {
            this.Plugin = plugin;

            var vistaUnlockedPtr = this.Plugin.Interface.TargetModuleScanner.ScanText("E8 ?? ?? ?? ?? E9 ?? ?? ?? ?? 41 8B CD E8 ?? ?? ?? ??");
            this.VistaUnlockedHook = new Hook<VistaUnlockedDelegate>(vistaUnlockedPtr, new VistaUnlockedDelegate(this.OnVistaUnlock));
            this.VistaUnlockedHook.Enable();

            var maskPtr = this.Plugin.Interface.TargetModuleScanner.GetStaticAddressFromSig("8B F2 48 8D 0D ?? ?? ?? ?? 8B D3");
            this.SightseeingMaskPointer = maskPtr;

            var createVfxPtr = this.Plugin.Interface.TargetModuleScanner.ScanText("E8 ?? ?? ?? ?? F3 0F 10 35 ?? ?? ?? ?? 48 89 43 08");
            this.CreateVfx = Marshal.GetDelegateForFunctionPointer<CreateVfxDelegate>(createVfxPtr);

            var playVfxPtr = this.Plugin.Interface.TargetModuleScanner.ScanText("E8 ?? ?? ?? ?? 8B 4B 7C 85 C9");
            this.PlayVfxInternal = Marshal.GetDelegateForFunctionPointer<PlayVfxDelegate>(playVfxPtr);

            var removeVfxPtr = this.Plugin.Interface.TargetModuleScanner.ScanText("40 53 48 83 EC 20 48 8B D9 48 8B 89 ?? ?? ?? ?? 48 85 C9 74 28 33 D2");
            this.RemoveVfx = Marshal.GetDelegateForFunctionPointer<RemoveVfxDelegate>(removeVfxPtr);
        }

        public void Dispose() {
            this.VistaUnlockedHook.Dispose();
        }

        private IntPtr OnVistaUnlock(ushort index, int a2, int a3) {
            this.Plugin.Markers.RemoveVfx(index);

            return this.VistaUnlockedHook.Original(index, a2, a3);
        }

        public unsafe IntPtr SpawnVfx(string name, Vector3 position) {
            var vfx = this.CreateVfx(name);

            var pos = (float*) (vfx + 80);
            *pos = position.X;
            *(pos + 1) = position.Z;
            *(pos + 2) = position.Y;

            pos = (float*) (vfx + 640);
            *pos = 0;
            *(pos + 1) = 0;
            *(pos + 2) = 0;

            *(long*) (vfx + 56) |= 2;
            *(int*) (vfx + 652) = 0;

            return vfx;
        }

        internal bool PlayVfx(IntPtr vfx) {
            return this.PlayVfxInternal(vfx, 0.0f, -1) == IntPtr.Zero;
        }

        public bool HasVistaUnlocked(short index) {
            if (this.SightseeingMaskPointer == IntPtr.Zero) {
                return false;
            }

            var byteToCheck = index >> 3;
            var bitToCheck = 1 << (index - 8 * byteToCheck);

            var maskPart = Marshal.ReadByte(this.SightseeingMaskPointer + byteToCheck);

            return (maskPart & bitToCheck) != 0;
        }
    }
}