using UnityEngine;
using UnityEngine.UI;

using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Text;

public class ImageInfo
{
    public int Left;
    public int Right;
    public SpriteInfo SpriteInfo;
}

public class TextPlus : Text
{
    #region 变量

    public ImagePlus ImagePlus
    {
        get
        {
            if (ImagePlus_ == null)
            {
                ImagePlus_ = GetComponentInChildren<ImagePlus>();
                
                if (ImagePlus_ == null)
                {
                    GameObject go = new GameObject("ImagePlus", typeof(ImagePlus));

                    RectTransform tra = go.GetComponent<RectTransform>();

                    tra.SetParent(rectTransform);
                }
            }

            return ImagePlus_;
        }
        set { ImagePlus_ = value; }
    }

    private ImagePlus ImagePlus_;

    public bool Draw;
    public bool SetY = false;
    public float Y = 0;
    public float LineHeight;
    public float MaxLineHeight = Mathf.Infinity;
    public VertexHelper ToFill;

    public List<int> RemovePos = new List<int>();
    public List<int> ImageIndex = new List<int>();
    public List<int> RemoveIndex = new List<int>();
    public List<int> NewTextIndex = new List<int>();

    public List<Vector3> NewTextPos = new List<Vector3>();

    public List<UIVertex> TextVertex = new List<UIVertex>();
    public List<UIVertex> ImageVertex = new List<UIVertex>();

    #endregion

    protected override void OnPopulateMesh(VertexHelper toFill)
    {
        base.OnPopulateMesh(toFill);

        List<ImageInfo> imageList = GetImageList();

        if (imageList.Count == 0)
        {
            Draw = false;
        }
        else
        {
            Draw = true;
        }
        
        if (Draw)
        {
            Draw = false;

            ToFill = toFill;

            Initialize();

            for (int i = 0; i < imageList.Count; i++)
            {
                for (int j = imageList[i].Left; j <= imageList[i].Right; j++)
                {
                    ClearChar(j);
                }

                RemoveChar(imageList[i]);

                CreateImage(imageList[i]);
            }

            for (int i = 0; i < RemovePos.Count; i++)
            {
                NewTextPos.RemoveAt(RemovePos[i] - i);
            }

            for (int i = 0; i < RemoveIndex.Count; i++)
            {
                NewTextIndex.RemoveAt(RemoveIndex[i] - i);
            }

            #region 调试

            //for (int i = 0; i < NewTextPos.Count; i+=6)
            //{
            //    Debug.Log(NewTextPos[i] + "   " + NewTextPos[i + 1] + "   " + NewTextPos[i + 2] + "   " + NewTextPos[i + 3] + "   " + NewTextPos[i + 4] + "   " + NewTextPos[i + 5]);
            //}

            //for (int i = 0; i < NewTextIndex.Count; i++)
            //{
            //    Debug.Log(NewTextIndex[i]);
            //}

            //for (int i = 0; i < ImageIndex.Count; i++)
            //{
            //    Debug.Log(ImageIndex[i]);
            //}

            #endregion
            
            Retract();

            for (int i = 0; i < ImageIndex.Count; i++)
            {
                UIVertex v0 = ImageVertex[0 + i*4];
                UIVertex v1 = ImageVertex[1 + i*4];
                UIVertex v2 = ImageVertex[2 + i*4];
                UIVertex v3 = ImageVertex[3 + i*4];

                v0.position = NewTextPos[0 + (ImageIndex[i] - i)*6];
                v1.position = NewTextPos[1 + (ImageIndex[i] - i)*6];
                v2.position = NewTextPos[2 + (ImageIndex[i] - i)*6];
                v3.position = NewTextPos[4 + (ImageIndex[i] - i)*6];

                ImageVertex[0 + i*4] = v0;
                ImageVertex[1 + i*4] = v1;
                ImageVertex[2 + i*4] = v2;
                ImageVertex[3 + i*4] = v3;

                NewTextPos.RemoveAt(0 + (ImageIndex[i] - i)*6);
                NewTextPos.RemoveAt(0 + (ImageIndex[i] - i)*6);
                NewTextPos.RemoveAt(0 + (ImageIndex[i] - i)*6);
                NewTextPos.RemoveAt(0 + (ImageIndex[i] - i)*6);
                NewTextPos.RemoveAt(0 + (ImageIndex[i] - i)*6);
                NewTextPos.RemoveAt(0 + (ImageIndex[i] - i)*6);

                NewTextIndex.RemoveAt(ImageIndex[i] - i);
            }

            for (int i = 0; i < NewTextIndex.Count; i++)
            {
                int index0 = 0 + NewTextIndex[i]*6;
                int index1 = 1 + NewTextIndex[i]*6;
                int index2 = 2 + NewTextIndex[i]*6;
                int index3 = 4 + NewTextIndex[i]*6;

                UIVertex v0 = TextVertex[index0];
                UIVertex v1 = TextVertex[index1];
                UIVertex v2 = TextVertex[index2];
                UIVertex v3 = TextVertex[index3];

                v0.position = NewTextPos[0 + i*6];
                v1.position = NewTextPos[1 + i*6];
                v2.position = NewTextPos[2 + i*6];
                v3.position = NewTextPos[4 + i*6];

                toFill.SetUIVertex(v0, 0 + NewTextIndex[i]*4);
                toFill.SetUIVertex(v1, 1 + NewTextIndex[i]*4);
                toFill.SetUIVertex(v2, 2 + NewTextIndex[i]*4);
                toFill.SetUIVertex(v3, 3 + NewTextIndex[i]*4);
            }

            ImagePlus.UpdateStatus(true, new VertexHelper(), ImageVertex);
        }
        else
        {
            ImagePlus.UpdateStatus(false, new VertexHelper(), null);
        }
    }


    protected void Initialize()
    {
        LineHeight = preferredHeight/cachedTextGenerator.lineCount;
        LineHeight = Mathf.Min(LineHeight, MaxLineHeight);
        //Debug.Log(transform.name + " " + LineHeight);

        ImageIndex = new List<int>();
        RemovePos = new List<int>();
        RemoveIndex = new List<int>();
        NewTextIndex = new List<int>();

        NewTextPos = new List<Vector3>();
        ImageVertex = new List<UIVertex>();
        
        ToFill.GetUIVertexStream(TextVertex);

        for (int i = 0; i < text.Length; i++)
        {
            NewTextIndex.Add(i);
        }

        for (int i = 0; i < TextVertex.Count; i++)
        {
            NewTextPos.Add(TextVertex[i].position);
        }
    }


    protected void Move(int index1, int index2, float x, float y)
    {
        Vector3 offset = new Vector3(x, y, 0);
        
        for (int i = index1; i <= index2; i++)
        {
            NewTextPos[0 + i * 6] += offset;
            NewTextPos[1 + i * 6] += offset;
            NewTextPos[2 + i * 6] += offset;
            NewTextPos[3 + i * 6] += offset;
            NewTextPos[4 + i * 6] += offset;
            NewTextPos[5 + i * 6] += offset;
        }
    }

    protected void Retract()
    {
        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < NewTextIndex.Count; i++)
        {
            sb.Append(text[NewTextIndex[i]]);
        }

        string newText = sb.ToString();


        List<int> endIndex = new List<int>();
        List<int> startIndex = new List<int>();
        List<List<int>> imageGroup = new List<List<int>>();

        imageGroup.Add(new List<int>());

        startIndex.Add(0);

        for (int i = 0; i < newText.Length; i++)
        {
            if (newText[i] == '\n')
            {
                endIndex.Add(i);
                startIndex.Add(i + 1);

                imageGroup.Add(new List<int>());
            }
            else if (newText[i] == '<')
            {
                ImageIndex.Add(i);
            }
        }

        endIndex.Add(-1);

        for (int i = 0; i < ImageIndex.Count; i++)
        {
            bool recycle = false;

            for (int j = 0; j < endIndex.Count; j++)
            {
                if (ImageIndex[i] < endIndex[j])
                {
                    imageGroup[j].Add(ImageIndex[i]);

                    recycle = true;

                    break;
                }
            }

            if (recycle)
            {
                continue;
            }

            imageGroup.Back(0).Add(ImageIndex[i]);
        }

        for (int i = 0; i < imageGroup.Count; i++)
        {
            RetractLine(endIndex[i], imageGroup[i]);
        }


        float offset;

        if (alignment == TextAnchor.LowerCenter || alignment == TextAnchor.MiddleCenter || alignment == TextAnchor.UpperCenter)
        {
            for (int i = 0; i < startIndex.Count; i++)
            {
                if (i == startIndex.Count - 1)
                {
                    offset = -GetWidth(startIndex[i], newText.Length - 1)/2;

                    offset -= NewTextPos[0 + startIndex[i] * 6].x;

                    Move(startIndex[i], newText.Length - 1, offset, 0);
                }
                else
                {
                    offset = -GetWidth(startIndex[i], endIndex[i]-1)/2;
                    
                    offset -= NewTextPos[0 + startIndex[i]*6].x;

                    Move(startIndex[i], endIndex[i]-1, offset, 0);
                }
            }
        }
        else if (alignment == TextAnchor.LowerRight || alignment == TextAnchor.MiddleRight || alignment == TextAnchor.UpperRight)
        {
            for (int i = 0; i < startIndex.Count; i++)
            {
                if (i == startIndex.Count - 1)
                {
                    offset = cachedTextGenerator.rectExtents.xMax / 2 - NewTextPos[1 + (newText.Length - 1) * 6].x;

                    Move(startIndex[i], newText.Length - 1, offset, 0);
                }
                else
                {
                    offset = cachedTextGenerator.rectExtents.xMax/2 - NewTextPos[1 + (endIndex[i] - 1)*6].x;

                    Move(startIndex[i], endIndex[i] - 1, offset, 0);
                }
            }
        }
        else if (alignment == TextAnchor.LowerLeft || alignment == TextAnchor.MiddleLeft || alignment == TextAnchor.UpperLeft)
        {

        }


        if (alignment == TextAnchor.LowerCenter || alignment == TextAnchor.LowerLeft || alignment == TextAnchor.LowerRight)
        {
            
        }
        else if (alignment == TextAnchor.MiddleCenter || alignment == TextAnchor.MiddleLeft || alignment == TextAnchor.MiddleRight)
        {
            
        }
        else if (alignment == TextAnchor.UpperCenter || alignment == TextAnchor.UpperLeft || alignment == TextAnchor.UpperRight)
        {
            
        }
    }

    protected void RetractLine(int endIndex, List<int> imageIndex)
    {
        if (imageIndex.Count == 0)
        {
            return;
        }

        int rear;
        int front;

        if (imageIndex.Count == 1)
        {
            rear = endIndex - 1;
            front = imageIndex[0] + 1;
            
            if (endIndex == -1)
            {
                rear = NewTextIndex.Count - 1;
            }

            if (rear < front)
            {
                return;
            }
            
            Move(front, rear, -GetSpan(imageIndex[0], front), 0);
        }
        else
        {
            for (int i = 0; i < imageIndex.Count; i++)
            {
                if (endIndex == -1)
                {
                    rear = NewTextIndex.Count - 1;
                }
                else
                {
                    rear = endIndex - 1;
                }

                front = imageIndex.Back(i) + 1;
                
                if (rear < front)
                {
                    continue;
                }
           
                Move(front, rear, -GetSpan(imageIndex.Back(i), front), 0);
            }
        }
    }


    protected void ClearChar(int index)
    {
        UIVertex v0 = TextVertex[0 + index*6];
        UIVertex v1 = TextVertex[1 + index*6];
        UIVertex v2 = TextVertex[2 + index*6];
        UIVertex v3 = TextVertex[4 + index*6];

        v0.uv0 = new Vector2();
        v1.uv0 = new Vector2();
        v2.uv0 = new Vector2();
        v3.uv0 = new Vector2();

        ToFill.SetUIVertex(v0, 0 + index * 4);
        ToFill.SetUIVertex(v1, 1 + index * 4);
        ToFill.SetUIVertex(v2, 2 + index * 4);
        ToFill.SetUIVertex(v3, 3 + index * 4);
    }

    protected void RemoveChar(ImageInfo imageInfo)
    {
        for (int i = imageInfo.Left + 1; i <= imageInfo.Right; i++)
        {
            RemoveIndex.Add(i);

            RemovePos.Add(0 + i*6);
            RemovePos.Add(1 + i*6);
            RemovePos.Add(2 + i*6);
            RemovePos.Add(3 + i*6);
            RemovePos.Add(4 + i*6);
            RemovePos.Add(5 + i*6);
        }
    }

    protected void CreateImage(ImageInfo imageInfo)
    {
        float height = LineHeight;

        float width = (height / imageInfo.SpriteInfo.Height) * imageInfo.SpriteInfo.Width;

        bool first = false;

        if (imageInfo.Left == 0)
        {
            first = true;
        }
        else if (!SameLine(imageInfo.Left-1, imageInfo.Left))
        {
            first = true;
        }
        
        UIVertex v0 = new UIVertex();
        UIVertex v1 = new UIVertex();
        UIVertex v2 = new UIVertex();
        UIVertex v3 = new UIVertex();

        v0.color = Color.white;
        v1.color = Color.white;
        v2.color = Color.white;
        v3.color = Color.white;

        v0.uv0 = imageInfo.SpriteInfo.UvList[0];
        v1.uv0 = imageInfo.SpriteInfo.UvList[1];
        v2.uv0 = imageInfo.SpriteInfo.UvList[2];
        v3.uv0 = imageInfo.SpriteInfo.UvList[3];

        if (first)
        {
            Vector3 middleLeft = (TextVertex[0 + imageInfo.Left*6].position + TextVertex[4 + imageInfo.Left*6].position)/2;

            v0.position = middleLeft + new Vector3(0, height/2);
            v1.position = middleLeft + new Vector3(width, height / 2);
            v2.position = middleLeft + new Vector3(width, -height / 2);
            v3.position = middleLeft + new Vector3(0, -height / 2);

            ImageVertex.Add(v0);
            ImageVertex.Add(v1);
            ImageVertex.Add(v2);
            ImageVertex.Add(v3);
        }
        else
        {
            Vector3 middleRight = (TextVertex[1 + (imageInfo.Left - 1) * 6].position + TextVertex[2 + (imageInfo.Left - 1) * 6].position) / 2;

            if (SetY)
            {
                middleRight.y = Y;
            }

            v0.position = middleRight + new Vector3(0, height / 2);
            v1.position = middleRight + new Vector3(width, height / 2);
            v2.position = middleRight + new Vector3(width, -height / 2);
            v3.position = middleRight + new Vector3(0, -height / 2);

            ImageVertex.Add(v0);
            ImageVertex.Add(v1);
            ImageVertex.Add(v2);
            ImageVertex.Add(v3);
        }

        NewTextPos[0 + imageInfo.Left*6] = v0.position;
        NewTextPos[1 + imageInfo.Left*6] = v1.position;
        NewTextPos[2 + imageInfo.Left*6] = v2.position;
        NewTextPos[3 + imageInfo.Left*6] = v2.position;
        NewTextPos[4 + imageInfo.Left*6] = v3.position;
        NewTextPos[5 + imageInfo.Left*6] = v0.position;
    }


    protected bool SameLine(int index1, int index2)
    {
        //if (text[index1] == '\n' || text[index2] == '\n')
        //{
        //    return false;
        //}

        if (Mathf.Abs(GetCenter(index1).y - GetCenter(index2).y) < LineHeight/4)
        {
            return true;
        }
        else
        {
            return false;
        }
    }


    protected float GetSpan(int index1, int index2)
    {
        return (NewTextPos[0 + index2*6].x - NewTextPos[1 + index1*6].x);
    }

    protected float GetWidth(int index1, int index2)
    {
        return (NewTextPos[1 + index2 * 6].x - NewTextPos[0 + index1 * 6].x);
    }

    protected float GetHeight(int index1, int index2)
    {
        return (NewTextPos[0 + index1 * 6].y - NewTextPos[2 + index2 * 6].y);
    }

    protected Vector3 GetCenter(int index)
    {
        return (TextVertex[0 + index*6].position + TextVertex[3 + index*6].position)/2;
    }

    protected List<ImageInfo> GetImageList()
    {
        List<ImageInfo> imageList = new List<ImageInfo>();

        ImageInfo imageInfo = new ImageInfo();

        for (int i = 0; i < text.Length; i++)
        {
            if (text[i] == '<')
            {
                if (i + 1 != text.Length)
                {
                    if (text[i + 1] == '(')
                    {
                        imageInfo = new ImageInfo();

                        imageInfo.Left = i;
                    }
                }
            }
            else if (text[i] == ')')
            {
                if (i + 1 != text.Length)
                {
                    if (text[i + 1] == '>')
                    {
                        imageInfo.Right = i + 1;

                        string imageName = text.Between(imageInfo.Left + 2, imageInfo.Right - 2);

                        if (SpriteAsset.SpriteInfoDic.TryGetValue(imageName, out imageInfo.SpriteInfo))
                        {
                            imageList.Add(imageInfo);
                        }
                    }
                }
            }
        }

        return imageList;
    }
}