using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using Dalamud.Game;
using Dalamud.Game.ClientState.Objects.Enums;
using Dalamud.Game.ClientState.Objects.Types;
using Dalamud.Game.Text;
using Dalamud.Game.Text.SeStringHandling;
using XivCommon.Functions.NamePlates;

namespace NominaOcculta {
    internal class Obscurer : IDisposable {
        private Plugin Plugin { get; }

        private Stopwatch UpdateTimer { get; } = new();
        private IList<string> Friends { get; set; }

        internal Obscurer(Plugin plugin) {
            this.Plugin = plugin;

            this.UpdateTimer.Start();

            this.Friends = this.Plugin.Common.Functions.FriendList.List
                .Select(friend => friend.Name.TextValue)
                .ToList();

            this.Plugin.Framework.Update += this.OnFrameworkUpdate;
            this.Plugin.Functions.AtkTextNodeSetText += this.OnAtkTextNodeSetText;
            this.Plugin.Common.Functions.NamePlates.OnUpdate += this.OnNamePlateUpdate;
            this.Plugin.ChatGui.ChatMessage += this.OnChatMessage;
        }

        public void Dispose() {
            this.Plugin.ChatGui.ChatMessage -= this.OnChatMessage;
            this.Plugin.Common.Functions.NamePlates.OnUpdate -= this.OnNamePlateUpdate;
            this.Plugin.Functions.AtkTextNodeSetText -= this.OnAtkTextNodeSetText;
            this.Plugin.Framework.Update -= this.OnFrameworkUpdate;
        }

        private void OnFrameworkUpdate(Framework framework) {
            if (this.UpdateTimer.Elapsed < TimeSpan.FromSeconds(5)) {
                return;
            }

            this.Friends = this.Plugin.Common.Functions.FriendList.List
                .Select(friend => friend.Name.TextValue)
                .ToList();
            this.UpdateTimer.Restart();
        }

        private void OnAtkTextNodeSetText(IntPtr node, IntPtr textPtr, ref SeString? overwrite) {
            // A catch-all for UI text. This is slow, so specialised methods should be preferred.

            var text = Util.ReadRawSeString(textPtr);

            var changed = this.ChangeNames(text);
            if (changed) {
                overwrite = text;
            }
        }

        private void OnNamePlateUpdate(NamePlateUpdateEventArgs args) {
            this.ChangeNames(args.Name);
            this.ChangeNames(args.Title); // for minions
        }

        private void OnChatMessage(XivChatType type, uint senderId, ref SeString sender, ref SeString message, ref bool isHandled) {
            this.ChangeNames(sender);
            this.ChangeNames(message);
        }

        private bool ChangeNames(SeString text) {
            if (!this.Plugin.Config.Enabled || !this.Plugin.NameRepository.Initialised) {
                return false;
            }

            var changed = false;

            var player = this.Plugin.ClientState.LocalPlayer;

            if (this.Plugin.Config.SelfFull) {
                var playerName = player?.Name.TextValue;
                if (playerName != null && text.ContainsPlayerName(playerName) && this.Plugin.NameRepository.GetReplacement(playerName, GetInfo(player!)) is { } replacement) {
                    text.ReplacePlayerName(playerName, replacement);
                    changed = true;
                }
            }

            if (this.Plugin.Config.SelfFirst || this.Plugin.Config.SelfLast) {
                var playerName = player?.Name.TextValue;
                if (playerName != null && this.Plugin.NameRepository.GetReplacement(playerName, GetInfo(player!)) is { } replacement) {
                    var parts = playerName.Split(' ', 2);
                    var replacementParts = replacement.Split(' ', 2);

                    if (this.Plugin.Config.SelfFirst && text.ContainsPlayerName(parts[0])) {
                        text.ReplacePlayerName(parts[0], replacementParts[0]);
                        changed = true;
                    }

                    if (this.Plugin.Config.SelfLast && text.ContainsPlayerName(parts[1])) {
                        text.ReplacePlayerName(parts[1], replacementParts[1]);
                        changed = true;
                    }
                }
            }

            if (this.Plugin.Config.Party) {
                foreach (var member in this.Plugin.PartyList) {
                    var name = member.Name.TextValue;

                    var info = ((byte) 0xFF, (byte) 0xFF, member.Sex);
                    if (member.GameObject is Character chara) {
                        info = GetInfo(chara);
                    }

                    if (member.ObjectId == player?.ObjectId || !text.ContainsPlayerName(name) || this.Plugin.NameRepository.GetReplacement(name, info) is not { } replacement) {
                        continue;
                    }

                    if (this.Plugin.Config.ExcludeFriends && this.Friends.Contains(name)) {
                        continue;
                    }

                    text.ReplacePlayerName(name, replacement);
                    changed = true;
                }
            }

            if (this.Plugin.Config.Others) {
                var party = this.Plugin.PartyList.Select(member => member.ObjectId).ToList();

                foreach (var obj in this.Plugin.ObjectTable) {
                    if (obj.ObjectKind != ObjectKind.Player || obj is not Character chara || obj.ObjectId == player?.ObjectId || party.Contains(obj.ObjectId)) {
                        continue;
                    }

                    var name = chara.Name.TextValue;
                    if (this.Plugin.Config.ExcludeFriends && this.Friends.Contains(name)) {
                        continue;
                    }

                    var info = GetInfo(chara);
                    if (info.race == 0) {
                        continue;
                    }

                    if (this.Plugin.NameRepository.GetReplacement(name, GetInfo(chara)) is not { } replacement) {
                        continue;
                    }

                    text.ReplacePlayerName(name, replacement);
                    changed = true;
                }
            }

            return changed;
        }

        private static (byte race, byte clan, byte gender) GetInfo(Character chara) {
            return (
                chara.Customize[(byte) CustomizeIndex.Race],
                (byte) ((chara.Customize[(byte) CustomizeIndex.Tribe] - 1) % 2),
                chara.Customize[(byte) CustomizeIndex.Gender]
            );
        }
    }
}