using UnityEngine;
using System.Collections;

//constants used for equations defined in this class.
public static class Constant
{

    /** \brief Convert parsec to kilometre. */
    const double PC_TO_KM = 3.08567758129e13;

    /** \brief Seconds per year. */
    const double SEC_PER_YEAR = 365.25 * 86400;

    /** \brief Deg to radian conversion faktor. */
    const double DEG_TO_RAD = Mathf.PI / 180.0;

    /** \brief Radian to deg conversion faktor. */
    const double RAD_TO_DEG = 180.0 / Mathf.PI;
};

//galaxy basics defined in this equation.
public class Galaxy
{
    public static int starCount = 20000;
    int numberOfHIIDustClouds = 100;
    public static int armCount = 4;
    public static int guidePointsPerArm = 20;
    public static int angleIncrement = 360 / guidePointsPerArm;
    public static int startArmAngle = 0;
    public static int armAngleIncrement = 360 / armCount;
    public static int distanceIncreaseFromCore = 10;
    public static int verticalMaxChange = 10;
    public static int totalGuidePoints = guidePointsPerArm * armCount;
    public static int seventyFive = 50;
    public static int twentyFive = 70;
    public static GuidePoint[] guidePointsArray = new GuidePoint[totalGuidePoints];
    public bool starsMade = false;

    public static Vector3 center = new Vector3(0, 0, 0);
    public static float radius = (float)(distanceIncreaseFromCore + (distanceIncreaseFromCore * guidePointsPerArm) + 20);

}

public class Star
{
    float m_temp;     // star temperature (in kelvin)
    float m_mag;      // brigtness;
    Color color = new Color();
    Vector3 m_pos;      // current position in kartesion koordinates

    //default constructor
    public Star()
    {
        m_temp = Random.Range(3000, 9001);//temperature is a random value between 3000 and 9000.
        m_mag = 1; //brightness will be highest because star defaults to center of galaxy.
        m_pos = new Vector3(0, 0, 0); //star defaults to center of galaxy position.
        color = calculateColorFromTemp(m_temp); //color will be calculated based on temperature.

    }
    //now a constructor with the three vectors (x,y,z) defined
    public Star(float x, float y, float z)
    {
        m_temp = Random.Range(3000, 9001);//temperature is a random value between 3000 and 9000.
        color = calculateColorFromTemp(m_temp); //color will be calculated based on temperature.
        m_pos = new Vector3(x, y, z); //set the position vector of this star.
        float distance = Vector3.Distance(Galaxy.center, m_pos);
        m_mag = calculateBrightnessFromDistance(distance); //calculate brightness based on distance from galactic center.
     }

    //getters
    public float getM_temp()
    {
        return m_temp;
    }
    public Color getColor()
    {
        return color;
    }
    public Vector3 getM_pos()
    {
        return m_pos;
    }
    public float getM_mag()
    {
        return m_mag;
    }

    //setters
    public void setM_temp(float m_temp)
    {
        this.m_temp = m_temp;
        color = calculateColorFromTemp(m_temp);
    }
    public void setM_pos(Vector3 m_pos)
    {
        this.m_pos = m_pos;
        float distance = Vector3.Distance(Galaxy.center, m_pos);
        m_mag = calculateBrightnessFromDistance(distance); //calculate brightness based on distance from galactic center.
    }
    public void setM_pos(float x, float y, float z)
    {
        m_pos = new Vector3(x, y, z); //set the position vector of this star.
        float distance = Vector3.Distance(Galaxy.center, m_pos);
        m_mag = calculateBrightnessFromDistance(distance); //calculate brightness based on distance from galactic center.
    }


    //private functions
    private Color calculateColorFromTemp(float temp)
    {
        //caculate color from temp using http://www.tannerhelland.com/4435/convert-temperature-rgb-algorithm-code/

        float calc_temp = temp / 100;
        float Red;
        float Green;
        float Blue;

        //R
        if (calc_temp <= 66)
        {
            Red = 255;
        }
        else
        {
            Red = calc_temp - 60;
            Red = 329.698727446f * Mathf.Pow(Red, 0.1332047592f);
            if (Red < 0) { Red = 0; }
            if (Red > 255) { Red = 255; }
        }

        //G
        if (calc_temp <= 66)
        {
            Green = calc_temp;
            Green = 99.4708025861f * Mathf.Log(Green) - 161.1195681661f;
            if (Green < 0) { Green = 0; }
            if (Green > 255) { Green = 255; }
        }
        else
        {
            Green = calc_temp - 60;
            Green = 288.1221695283f * Mathf.Pow(Green, -0.0755148492f);
            if (Green < 0) { Green = 0; }
            if (Green > 255) { Green = 255; }
        }

        //B
        if (calc_temp >= 66)
        {
            Blue = 255;
        }
        else if (calc_temp <= 19)
        {
            Blue = 0;
        }
        else
        {
            Blue = calc_temp - 10;
            Blue = 138.5177312231f * Mathf.Log(Blue) - 305.0447927307f;
            if (Blue < 0) { Blue = 0; }
            if (Blue > 255) { Blue = 255; }
        }

        color = new Color(Red, Green, Blue); //finally, create the color and assign it to the variable.
        return color;

    }

    private float calculateBrightnessFromDistance(float distance) //with 1 being maximum, 0 being no brightness
    {

        float brightness;
        float percent_distance = distance / Galaxy.radius;
        float working_distance = percent_distance * 2;
        //this is an exponential decay curve, with brightness as y and working_distance as x.
        //at 0, brightness is 1, while at 2, brightness is a little over 0.
        brightness = (Mathf.Pow(working_distance, -2));
        return brightness;

    }
}

public class GuidePoint
{
    //attributes/properties
    private Vector3 m_pos = new Vector3();
    private int ID;
    private static int guide_point_count = -1; //minus 1, cause first guide point is galactic center and has id of -1.
    private static Color color = Color.yellow;

    //constructors
    //default constructor
    public GuidePoint()
    {
        m_pos = new Vector3(0, 0, 0);
        ID = -4;
    }
    //designated constructor
    public GuidePoint(float x_coordinate, float y_coordinate, float z_coordinate)
    {
        m_pos = new Vector3(x_coordinate, y_coordinate, z_coordinate);
        ID = guide_point_count;
        guide_point_count++;
    }

    //getters
    public Vector3 getM_pos()
    {
        return m_pos;
    }
    public int getID()
    {
        return ID;
    }
    public int getGuidePointCount()
    {
        return guide_point_count;
    }

    //setters
    public void setM_pos(Vector3 m_pos)
    {
        this.m_pos = m_pos;
    }

    //adders
    public void addID()
    {
        ID = guide_point_count;
        guide_point_count++;
    }
}


public class galaxygenerationstwo : MonoBehaviour {

	// Use this for initialization
	void Start () {

	}

	// Update is called once per frame
	void Update () {

	}
}