using System;
using System.Collections.Generic;
using OTGIntegrated.Core;
using OTGIntegrated.Player;
using OTGIntegrated.Quests;
using OTGIntegrated.UI;
using UnityEngine;

namespace OTGIntegrated.Dialogue
{
    public sealed class DialogueManager : MonoBehaviour
    {
        public DialogueUI dialogueUI;

        private QuestManager questManager;
        private UIManager uiManager;
        private PlayerController playerController;
        private NPCInteract currentNpc;
        private DialogueNode currentNode;

        public bool IsDialogueActive { get; private set; }

        public void Initialize(QuestManager questManager, UIManager uiManager, PlayerController playerController)
        {
            this.questManager = questManager;
            this.uiManager = uiManager;
            this.playerController = playerController;
            if (dialogueUI == null)
            {
                dialogueUI = FindObjectOfType<DialogueUI>(true);
            }
        }

        private void Update()
        {
            if (IsDialogueActive && Input.GetKeyDown(KeyCode.Escape))
            {
                EndDialogue();
            }
        }

        public void StartDialogue(NPCInteract npc)
        {
            if (npc == null || npc.startNode == null)
            {
                return;
            }

            currentNpc = npc;
            IsDialogueActive = true;
            questManager?.NotifyNpcTalked(npc.npcId);

            if (uiManager != null)
            {
                uiManager.OpenDialogue();
            }
            else if (playerController != null)
            {
                playerController.SetInputEnabled(false);
            }

            Cursor.lockState = CursorLockMode.None;
            Cursor.visible = true;
            ShowNode(npc.startNode);
        }

        public void ShowNode(DialogueNode node)
        {
            if (node == null)
            {
                EndDialogue();
                return;
            }

            currentNode = node;
            string speaker = !string.IsNullOrWhiteSpace(node.speakerName)
                ? node.speakerName
                : currentNpc != null ? currentNpc.displayName : "NPC";

            List<DialogueChoice> choices = BuildChoices(node);
            dialogueUI?.Show(speaker, node.npcLine, choices);
        }

        public void EndDialogue()
        {
            if (!IsDialogueActive)
            {
                return;
            }

            IsDialogueActive = false;
            currentNpc = null;
            currentNode = null;
            dialogueUI?.Hide();

            if (uiManager != null)
            {
                uiManager.CloseDialogue();
            }
            else if (playerController != null)
            {
                playerController.SetInputEnabled(true);
                Cursor.lockState = CursorLockMode.Locked;
                Cursor.visible = false;
            }
        }

        private List<DialogueChoice> BuildChoices(DialogueNode node)
        {
            List<DialogueChoice> choices = new List<DialogueChoice>();

            if (currentNpc != null && currentNpc.offeredQuest != null && questManager != null)
            {
                QuestData quest = currentNpc.offeredQuest;
                if (!questManager.IsQuestActive(quest) && !questManager.IsQuestCompleted(quest))
                {
                    choices.Add(new DialogueChoice($"Взять квест: {quest.displayName}", () =>
                    {
                        questManager.StartQuest(quest);
                        EndDialogue();
                    }));
                }
            }

            if (currentNpc != null && currentNpc.completionQuest != null && questManager != null)
            {
                QuestData quest = currentNpc.completionQuest;
                if (questManager.IsQuestReady(quest))
                {
                    choices.Add(new DialogueChoice($"Завершить квест: {quest.displayName}", () =>
                    {
                        questManager.TryCompleteQuest(quest, currentNpc.npcId);
                        EndDialogue();
                    }));
                }
            }

            if (node.responses != null)
            {
                for (int i = 0; i < node.responses.Length; i++)
                {
                    DialogueResponse response = node.responses[i];
                    if (response == null || string.IsNullOrWhiteSpace(response.responseText))
                    {
                        continue;
                    }

                    choices.Add(new DialogueChoice(response.responseText, () => SelectResponse(response)));
                }
            }

            if (currentNpc != null && currentNpc.canOpenCrafting)
            {
                choices.Add(new DialogueChoice("Открыть крафт", () =>
                {
                    EndDialogue();
                    uiManager?.OpenCrafting();
                }));
            }

            choices.Add(new DialogueChoice("Закончить разговор", EndDialogue));
            return choices;
        }

        private void SelectResponse(DialogueResponse response)
        {
            if (response == null)
            {
                EndDialogue();
                return;
            }

            if (response.questToStart != null && questManager != null)
            {
                questManager.StartQuest(response.questToStart);
            }

            if (response.questToComplete != null && currentNpc != null && questManager != null)
            {
                questManager.TryCompleteQuest(response.questToComplete, currentNpc.npcId);
            }

            if (response.openCrafting)
            {
                EndDialogue();
                uiManager?.OpenCrafting();
                return;
            }

            if (!response.endsDialogue && response.nextNode == null)
            {
                ShowInformationalFollowUp();
                return;
            }

            if (response.endsDialogue || response.nextNode == null)
            {
                EndDialogue();
            }
            else
            {
                ShowNode(response.nextNode);
            }
        }

        private void ShowInformationalFollowUp()
        {
            string speaker = currentNpc != null ? currentNpc.displayName : currentNode != null ? currentNode.speakerName : "NPC";
            string text = GetInformationalText();
            List<DialogueChoice> choices = new List<DialogueChoice>
            {
                new DialogueChoice("Назад", () => ShowNode(currentNode)),
                new DialogueChoice("Закончить разговор", EndDialogue)
            };

            dialogueUI?.Show(speaker, text, choices);
        }

        private string GetInformationalText()
        {
            string npcId = currentNpc != null ? currentNpc.npcId : string.Empty;
            switch (npcId)
            {
                case "Elder":
                    return "Нужна обычная древесина из леса. Собери 5 Wood, затем вернись ко мне, чтобы завершить квест.";
                case "Guard":
                    return "Гоблины стоят в лагере на юго-востоке. Уничтожь 3 Goblin оружием или способностями и возвращайся за наградой.";
                case "Blacksmith":
                    return "Для Iron Axe нужны Wood x2, Stone x2 и Iron Ore x1. Открой верстак через E рядом со столом или клавишей C.";
                case "Mage":
                    return "Fireball на 1 тратит ману и наносит урон. Heal на 2 лечит. Blink на 3 переносит вперёд. Таланты открываются на K.";
                default:
                    return currentNode != null ? currentNode.npcLine : "Подробностей пока нет.";
            }
        }
    }

    public sealed class DialogueChoice
    {
        public string Text { get; }
        public Action Callback { get; }

        public DialogueChoice(string text, Action callback)
        {
            Text = text;
            Callback = callback;
        }
    }
}