/* ---------------------------------------
 * Author:          Martin Pane (martintayx@gmail.com) (@tayx94)
 * Collaborators:   Lars Aalbertsen (@Rockylars)
 * Project:         Graphy - Ultimate Stats Monitor
 * Date:            22-Nov-17
 * Studio:          Tayx
 * 
 * This project is released under the MIT license.
 * Attribution is not required, but it is always welcomed!
 * -------------------------------------*/

using UnityEngine;
using UnityEngine.UI;

namespace Tayx.Graphy
{
    /// <summary>
    /// This class communicates directly with the shader to draw the graphs. Performance here is of upmost importance
    /// to reduce as much overhead as possible, as we are updating hundreds of values every frame.
    /// </summary>
    public class G_GraphShader
    {
        /* ----- TODO: ----------------------------
         * Add summaries to the variables.
         * --------------------------------------*/

        #region Variables -> Array

        public const int    ArrayMaxSizeFull            = 512;
        public const int    ArrayMaxSizeLight           = 128;

        public int          ArrayMaxSize                = 128;

        public float[]      Array;                                              // The values

        #endregion

        #region Variables -> Image

        public Image        Image                       = null;

        #endregion

        #region Variables -> Name

        private string      Name                        = "GraphValues";        // The name of the array
        private string      Name_Length                 = "GraphValues_Length";

        #endregion

        #region Variables -> Average

        public float        Average                     = 0;
        private int         averagePropertyId           = 0;

        #endregion

        #region Variables -> Thresholds

        public float        GoodThreshold               = 0;
        public float        CautionThreshold            = 0;

        private int         goodThresholdPropertyId     = 0;
        private int         cautionThresholdPropertyId  = 0;

        #endregion

        #region Variables -> Color

        public Color        GoodColor                   = Color.white;
        public Color        CautionColor                = Color.white;
        public Color        CriticalColor               = Color.white;

        private int         goodColorPropertyId         = 0;
        private int         cautionColorPropertyId      = 0;
        private int         criticalColorPropertyId     = 0;

        #endregion

        #region Methods -> Public

        /// <summary>
        /// This is done to avoid a design problem that arrays in shaders have, 
        /// and should be called before initializing any shader graph.
        /// The first time that you use initialize an array, the size of the array in the shader is fixed.
        /// This is why sometimes you will get a warning saying that the array size will be capped.
        /// It shouldn't generate any issues, but in the worst case scenario just reset the Unity Editor
        /// (if for some reason the shaders reload).
        /// I also cache the Property IDs, that make access faster to modify shader parameters.
        /// </summary>
        public void InitializeShader()
        {
            Image.material.SetFloatArray(Name, new float[ArrayMaxSize]);

            averagePropertyId           = Shader.PropertyToID("Average");

            goodThresholdPropertyId     = Shader.PropertyToID("_GoodThreshold");
            cautionThresholdPropertyId  = Shader.PropertyToID("_CautionThreshold");

            goodColorPropertyId         = Shader.PropertyToID("_GoodColor");
            cautionColorPropertyId      = Shader.PropertyToID("_CautionColor");
            criticalColorPropertyId     = Shader.PropertyToID("_CriticalColor");
        }

        /// <summary>
        /// Updates the material linked with this shader graph  with the values in the float[] array.
        /// </summary>
        public void UpdateArray()
        {
            Image.material.SetInt(Name_Length, Array.Length);
        }

        /// <summary>
        /// Updates the average parameter in the material.
        /// </summary>
        public void UpdateAverage()
        {
            Image.material.SetFloat(averagePropertyId, Average);
        }
        
        /// <summary>
        /// Updates the thresholds in the material.
        /// </summary>
        public void UpdateThresholds()
        {
            Image.material.SetFloat(goodThresholdPropertyId, GoodThreshold);
            Image.material.SetFloat(cautionThresholdPropertyId, CautionThreshold);
        }
        
        /// <summary>
        /// Updates the colors in the material.
        /// </summary>
        public void UpdateColors()
        {
            Image.material.SetColor(goodColorPropertyId, GoodColor);
            Image.material.SetColor(cautionColorPropertyId, CautionColor);
            Image.material.SetColor(criticalColorPropertyId, CriticalColor);
        }

        /// <summary>
        /// Updates the points in the graph with the set array of values.
        /// </summary>
        public void UpdatePoints()
        {
            // Requires an array called "name"
            // and another one called "name_Length"

            Image.material.SetFloatArray(Name, Array);
         }

        #endregion
    }
}