using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.Events;
using UnityEngine.EventSystems;

namespace DuloGames.UI
{
    public class Demo_Chat : MonoBehaviour
    {
        [System.Serializable]
        public enum TextEffect
        {
            None,
            Shadow,
            Outline
        }

        [System.Serializable]
        public class SendMessageEvent : UnityEvent<int, string> { }

        [System.Serializable]
        public class TabInfo
        {
            public int id = 0;
            public UITab button;
            public Transform content;
            public ScrollRect scrollRect;
        }

        [SerializeField] private InputField m_InputField;
        [Header("Buttons")]
        [SerializeField] private Button m_Submit;
        [SerializeField] private Button m_ScrollTopButton;
        [SerializeField] private Button m_ScrollBottomButton;
        [SerializeField] private Button m_ScrollUpButton;
        [SerializeField] private Button m_ScrollDownButton;

        [Header("Tab Properties")]
        [SerializeField] private List<TabInfo> m_Tabs = new List<TabInfo>();

        [Header("Text Properties")]
        [SerializeField] private Font m_TextFont = FontData.defaultFontData.font;
        [SerializeField] private int m_TextFontSize = FontData.defaultFontData.fontSize;
        [SerializeField] private float m_TextLineSpacing = FontData.defaultFontData.lineSpacing;
        [SerializeField] private Color m_TextColor = Color.white;
        [SerializeField] private TextEffect m_TextEffect = TextEffect.None;
        [SerializeField] private Color m_TextEffectColor = Color.black;
        [SerializeField] private Vector2 m_TextEffectDistance = new Vector2(1f, -1f);

        [Header("Events")]
        /// <summary>
        /// Fired when the clients sends a chat message.
        /// First paramenter - int tabId.
        /// Second parameter - string messageText.
        /// </summary>
        public SendMessageEvent onSendMessage = new SendMessageEvent();

        private TabInfo m_ActiveTabInfo;

        protected void Awake()
        {
            // Find the active tab info
            this.m_ActiveTabInfo = this.FindActiveTab();

            // Clear the lines of text
            if (this.m_Tabs != null && this.m_Tabs.Count > 0)
            {
                foreach (TabInfo info in this.m_Tabs)
                {
                    // if we have a button
                    if (info.content != null)
                    {
                        foreach (Transform t in info.content)
                        {
                            Destroy(t.gameObject);
                        }
                    }
                }
            }
        }
        
        protected void OnEnable()
        {
            // Hook the submit button click event
            if (this.m_Submit != null)
            {
                this.m_Submit.onClick.AddListener(OnSubmitClick);
            }

            // Hook the scroll up button click event
            if (this.m_ScrollUpButton != null)
            {
                this.m_ScrollUpButton.onClick.AddListener(OnScrollUpClick);
            }

            // Hook the scroll down button click event
            if (this.m_ScrollDownButton != null)
            {
                this.m_ScrollDownButton.onClick.AddListener(OnScrollDownClick);
            }

            // Hook the scroll to top button click event
            if (this.m_ScrollTopButton != null)
            {
                this.m_ScrollTopButton.onClick.AddListener(OnScrollToTopClick);
            }

            // Hook the scroll to bottom button click event
            if (this.m_ScrollBottomButton != null)
            {
                this.m_ScrollBottomButton.onClick.AddListener(OnScrollToBottomClick);
            }

            // Hook the input field end edit event
            if (this.m_InputField != null)
            {
                this.m_InputField.onEndEdit.AddListener(OnInputEndEdit);
            }

            // Hook the tab toggle change events
            if (this.m_Tabs != null && this.m_Tabs.Count > 0)
            {
                foreach (TabInfo info in this.m_Tabs)
                {
                    // if we have a button
                    if (info.button != null)
                    {
                        info.button.onValueChanged.AddListener(OnTabStateChange);
                    }
                }
            }
        }

        protected void OnDisable()
        {
            // Unhook the submit button click event
            if (this.m_Submit != null)
            {
                this.m_Submit.onClick.RemoveListener(OnSubmitClick);
            }

            // Unhook the scroll up button click event
            if (this.m_ScrollUpButton != null)
            {
                this.m_ScrollUpButton.onClick.RemoveListener(OnScrollUpClick);
            }

            // Unhook the scroll down button click event
            if (this.m_ScrollDownButton != null)
            {
                this.m_ScrollDownButton.onClick.RemoveListener(OnScrollDownClick);
            }

            // Unhook the scroll to top button click event
            if (this.m_ScrollTopButton != null)
            {
                this.m_ScrollTopButton.onClick.RemoveListener(OnScrollToTopClick);
            }

            // Unhook the scroll to bottom button click event
            if (this.m_ScrollBottomButton != null)
            {
                this.m_ScrollBottomButton.onClick.RemoveListener(OnScrollToBottomClick);
            }

            // Unhook the tab toggle change events
            if (this.m_Tabs != null && this.m_Tabs.Count > 0)
            {
                foreach (TabInfo info in this.m_Tabs)
                {
                    // if we have a button
                    if (info.button != null)
                    {
                        info.button.onValueChanged.RemoveListener(OnTabStateChange);
                    }
                }
            }
        }

        /// <summary>
        /// Fired when the submit button is clicked.
        /// </summary>
        public void OnSubmitClick()
        {
            // Get the input text
            if (this.m_InputField != null)
            {
                string text = this.m_InputField.text;

                // Make sure we have input text
                if (!string.IsNullOrEmpty(text))
                {
                    // Send the message
                    this.SendChatMessage(text);
                }
            }
        }

        /// <summary>
        /// Fired when the scroll up button is pressed.
        /// </summary>
        public void OnScrollUpClick()
        {
            if (this.m_ActiveTabInfo == null || this.m_ActiveTabInfo.scrollRect == null)
                return;
            
            PointerEventData pointerEventData = new PointerEventData(EventSystem.current);
            pointerEventData.scrollDelta = new Vector2(0f, 1f);

            this.m_ActiveTabInfo.scrollRect.OnScroll(pointerEventData);
        }

        /// <summary>
        /// Fired when the scroll down button is pressed.
        /// </summary>
        public void OnScrollDownClick()
        {
            if (this.m_ActiveTabInfo == null || this.m_ActiveTabInfo.scrollRect == null)
                return;

            PointerEventData pointerEventData = new PointerEventData(EventSystem.current);
            pointerEventData.scrollDelta = new Vector2(0f, -1f);

            this.m_ActiveTabInfo.scrollRect.OnScroll(pointerEventData);
        }

        /// <summary>
        /// Fired when the scroll to top button is pressed.
        /// </summary>
        public void OnScrollToTopClick()
        {
            if (this.m_ActiveTabInfo == null || this.m_ActiveTabInfo.scrollRect == null)
                return;

            // Scroll to top
            this.m_ActiveTabInfo.scrollRect.verticalNormalizedPosition = 1f;
        }

        /// <summary>
        /// Fired when the scroll to bottom button is pressed.
        /// </summary>
        public void OnScrollToBottomClick()
        {
            if (this.m_ActiveTabInfo == null || this.m_ActiveTabInfo.scrollRect == null)
                return;

            // Scroll to bottom
            this.m_ActiveTabInfo.scrollRect.verticalNormalizedPosition = 0f;
        }

        /// <summary>
        /// Fired when the input field is submitted.
        /// </summary>
        /// <param name="text"></param>
        public void OnInputEndEdit(string text)
        {
            // Make sure we have input text
            if (!string.IsNullOrEmpty(text))
            {
                // Make sure the return key is pressed
                if (Input.GetKey(KeyCode.Return))
                {
                    // Send the message
                    this.SendChatMessage(text);
                }
            }
        }
        
        /// <summary>
        /// Fired when a tab button is toggled.
        /// </summary>
        /// <param name="state"></param>
        public void OnTabStateChange(bool state)
        {
            // If a tab was activated
            if (state)
            {
                // Find the active tab
                this.m_ActiveTabInfo = this.FindActiveTab();
            }
        }

        /// <summary>
        /// Finds the active tab based on the tab buttons toggle state.
        /// </summary>
        /// <returns>The active tab info.</returns>
        private TabInfo FindActiveTab()
        {
            // If we have tabs
            if (this.m_Tabs != null && this.m_Tabs.Count > 0)
            {
                foreach (TabInfo info in this.m_Tabs)
                {
                    // if we have a button
                    if (info.button != null)
                    {
                        // If this button is active
                        if (info.button.isOn)
                        {
                            return info;
                        }
                    }
                }
            }

            return null;
        }

        /// <summary>
        /// Gets the tab info for the specified tab by id.
        /// </summary>
        /// <param name="tabId">Tab id.</param>
        /// <returns></returns>
        public TabInfo GetTabInfo(int tabId)
        {
            // If we have tabs
            if (this.m_Tabs != null && this.m_Tabs.Count > 0)
            {
                foreach (TabInfo info in this.m_Tabs)
                {
                    // If this is the tab we are looking for
                    if (info.id == tabId)
                    {
                        return info;
                    }
                }
            }

            return null;
        }

        /// <summary>
        /// Sends a chat message.
        /// </summary>
        /// <param name="text">The message.</param>
        private void SendChatMessage(string text)
        {
            int tabId = (this.m_ActiveTabInfo != null ? this.m_ActiveTabInfo.id : 0);

            // Trigger the event
            if (this.onSendMessage != null)
            {
                this.onSendMessage.Invoke(tabId, text);
            }

            // Clear the input field
            if (this.m_InputField != null)
            {
                this.m_InputField.text = "";
            }
        }

        /// <summary>
        /// Adds a chat message to the specified tab.
        /// </summary>
        /// <param name="tabId">The tab id.</param>
        /// <param name="text">The message.</param>
        public void ReceiveChatMessage(int tabId, string text)
        {
            TabInfo tabInfo = this.GetTabInfo(tabId);

            // Make sure we have tab info
            if (tabInfo == null || tabInfo.content == null)
                return;

            // Create the text line
            GameObject obj = new GameObject("Text " + tabInfo.content.childCount.ToString(), typeof(RectTransform));

            // Prepare the game object
            obj.layer = this.gameObject.layer;

            // Get the rect transform
            RectTransform rectTransform = (obj.transform as RectTransform);

            // Prepare the rect transform
            rectTransform.localScale = new Vector3(1f, 1f, 1f);
            rectTransform.pivot = new Vector2(0f, 1f);
            rectTransform.anchorMin = new Vector2(0f, 1f);
            rectTransform.anchorMax = new Vector2(0f, 1f);

            // Set the parent
            rectTransform.SetParent(tabInfo.content, false);

            // Add the text component
            Text textComp = obj.AddComponent<Text>();

            // Prepare the text component
            textComp.font = this.m_TextFont;
            textComp.fontSize = this.m_TextFontSize;
            textComp.lineSpacing = this.m_TextLineSpacing;
            textComp.color = this.m_TextColor;
            textComp.text = text;

            // Prepare the text effect
            if (this.m_TextEffect != TextEffect.None)
            {
                switch (this.m_TextEffect)
                {
                    case TextEffect.Shadow:
                        Shadow shadow = obj.AddComponent<Shadow>();
                        shadow.effectColor = this.m_TextEffectColor;
                        shadow.effectDistance = this.m_TextEffectDistance;
                        break;
                    case TextEffect.Outline:
                        Outline outline = obj.AddComponent<Outline>();
                        outline.effectColor = this.m_TextEffectColor;
                        outline.effectDistance = this.m_TextEffectDistance;
                        break;
                }
            }

            // Rebuild the content layout
            LayoutRebuilder.ForceRebuildLayoutImmediate(tabInfo.content as RectTransform);

            // Scroll to bottom
            this.OnScrollToBottomClick();
        }
    }
}