using System;

using UnityEngine;

namespace Framework.Support {

  /// <summary>Stores a range with a start value and an end value</summary>
  [Serializable]
  public struct Range {

    /// <summary>An empty range</summary>
    public static readonly Range Empty = new Range(0.0f, 0.0f);

    /// <summary>Position or time the interval begins at</summary>
    public float Start;
    /// <summary>Position or time the interval ends at</summary>
    public float End;

    /// <summary>Initializes a new interval from the specified end points</summary>
    /// <param name="start">Position or time at which the interval will begin</param>
    /// <param name="end">Position or time at which the interval will end</param>
    public Range(float start, float end) {
      this.Start = start;
      this.End = end;
    }

    /// <summary>Checks whether the interval contains the specified point</summary>
    /// <param name="point">Point the interval will be checked against</param>
    /// <returns>True if the interval contains the specified point</returns>
    public bool Contains(float point) {
      return (point >= this.Start) && (point < this.End);
    }

    /// <summary>Checks whether the interval intersects another interval</summary>
    /// <param name="other">Other interval to check for an intersection against</param>
    /// <returns>True if this interval intersects the other interval</returns>
    public bool Intersects(Range other) {
      return (this.End >= other.Start) && (other.End >= this.Start);
    }

    /// <summary>Whether the interval is flipped</summary>
    /// <returns>True if the interval is flipped, false otherwise</returns>
    public bool IsFlipped {
      get { return (this.End < this.Start); }
    }

    /// <summary>Locates the center of the range</summary>
    public float Center {
      get { return (this.Start + this.End) / 2.0f; }
    }

    /// <summary>Calculates the length of the range</summary>
    public float Length {
      get { return (this.End - this.Start); }
    }

    /// <summary>Returns a random point within the interval</summary>
    /// <returns>A random point within the interval</returns>
    public float Random() {
      return UnityEngine.Random.Range(this.Start, this.End);
    }

    /// <summary>Returns a hash code that will be match between identical instances</summary>
    /// <returns>A hash code for the instance</returns>
    public override int GetHashCode() {
      return this.Start.GetHashCode() ^ this.End.GetHashCode();
    }

    /// <summary>Provides a human-readable string representation of the interval</summary>
    /// <returns>The string representation of the interval</returns>
    public override string ToString() {
      return "{Interval " + this.Start.ToString() + " - " + this.End.ToString() + "}";
    }

  }

} // namespace Framework.Support