using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using KairoEngine.Core;
using Ink.Runtime;
using UniRx;

namespace KairoEngine.StorySystem
{
    // Todo: Request events for getting and setting story variables

    public class StoryController
    {
	    private TextAsset inkJSONAsset = null;
	    private Story story;
        private string name;
        private bool logText = false;
        private bool started = false;
        private int lineInverval = 250;

        public bool wait = false;
        
        private CompositeDisposable disposables = new CompositeDisposable();
        private List<StoryObject> storyObjects;

        public StoryController(TextAsset inkJSONAsset, string storyName, bool logText = false)
        {
            this.inkJSONAsset = inkJSONAsset;
            this.name = storyName;
            this.story = new Story (inkJSONAsset.text);
            this.logText = logText;
        }

        public StoryController(TextAsset inkJSONAsset, string storyName, List<StoryObject> storyObjects, Transform parent = null, bool logText = false, int lineInverval = 250)
        {
            this.inkJSONAsset = inkJSONAsset;
            this.name = storyName;
            this.story = new Story (inkJSONAsset.text);
            this.logText = logText;
            this.lineInverval = lineInverval;
            this.storyObjects = storyObjects;
            foreach (var item in storyObjects) 
            {
                item.instance = GameObject.Instantiate(item.prefab, parent);
                item.instance.SetActive(false);
                item.instance.name = item.instance.name.Replace("(Clone)", "");
            }
        }

        public void Start()
        {
            if(started) return;
            started = true;
            GenericEvents.StartListening(name, JumpToPath);
            EventManager.broadcast.StartListening(name, SelectStoryBranch);
            EventManager.broadcast.StartListening(name, PublishStorylineToObservers);
            if(logText) Debug.Log($"Starting {name}");
            story.BindExternalFunction ("WaitForTime", (int time) => Wait(time), false);
            story.BindExternalFunction ("Enable", (string name) => EnableGameObject(name), false);
            story.BindExternalFunction ("Disable", (string name) => DisableGameObject(name), false); 
            story.BindExternalFunction ("TriggerEvent", (string name) => GenericEvents.Trigger(name), false);
            var storyStream = Observable.Interval(TimeSpan.FromMilliseconds(250))
                //.Where(_ => wait == false)
                .Subscribe(_ => StoryLoop())
                .AddTo(disposables);
        } 

        public void Stop()
        {
            GenericEvents.StopListening(name, JumpToPath);
            EventManager.broadcast.StopListening(name, SelectStoryBranch);
            EventManager.broadcast.StopListening(name, PublishStorylineToObservers);
            disposables.Clear();
            started = false;
            if(logText) Debug.Log($"{name} has stoped.");
        }

        private void StoryLoop()
        {
            //Debug.Log(wait);
            if(wait) return;
            // Read all the content until we can't continue any more
            if (story.canContinue) {
                // Continue gets the next line of the story
                string text = story.Continue ();
                // This removes any white space from the text.
                text = text.Trim();
                // Create StoryStepData
                StoryStepData storyStep = new StoryStepData(StoryStepType.Line, text, story.currentTags, null);
                EventManager.broadcast.Trigger(name, storyStep);
                // Display the text if log is enabled
                if(logText) Debug.Log(storyStep.text);
            }
            else if( story.currentChoices.Count > 0 ) 
            {
                List<string> choices = new List<string>();
                for (int i = 0; i < story.currentChoices.Count; ++i) 
                {
                    Choice choice = story.currentChoices [i];
                    choices.Add(choice.text);
                    if(logText) Debug.Log($"Choice {i + 1}. {choice.text}");
                }
                StoryStepData storyStep = new StoryStepData(StoryStepType.Branch, "", story.currentTags, choices);
                EventManager.broadcast.Trigger(name, storyStep);
                wait = true;
            }
            else Stop(); 
        }

        private void SelectStoryBranch(StoryStepData storyStep)
        {
            if(storyStep.category == StoryStepType.Path)
            {
                story.ChooseChoiceIndex (storyStep.path);
                wait = false;
                StoryLoop();
            }
        }

        static Subject<StoryStepData> subject;

        public static IObservable<StoryStepData> Lines()
        {
            if(subject == null) subject = new Subject<StoryStepData>();
            return subject.AsObservable();
        }

        private void PublishStorylineToObservers(StoryStepData storyStep)
        {
            if(subject != null) subject.OnNext(storyStep);
        }

        public void JumpToPath(string path)
        {
            if(story != null) 
            {
                if(logText) Debug.Log($"Jumping to story knot \"{path}\"");
                story.ChoosePathString(path);
                wait = false;
            }
        }

        #region ExternalStoryFunctions

        private void Wait(int time)
        {
            wait = true;
            Timer.Execute(time, () => wait = false);
        }

        private void EnableGameObject(string name)
        {
            for (int i = 0; i < storyObjects.Count; i++)
            {
                if(storyObjects[i].name == name) storyObjects[i].instance.SetActive(true);
            }
        }

        private void DisableGameObject(string name)
        {
            for (int i = 0; i < storyObjects.Count; i++)
            {
                if(storyObjects[i].name == name) storyObjects[i].instance.SetActive(false);
            }
        }

        #endregion
    }
}