/*
 * Copyright 2016 The Cartographer Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using  RobotNet10.Shared.Numbers;

namespace CartographerSharp.Common.Math;

/// <summary>
/// 2D integer array (equivalent to Eigen::Array2i).
/// Optimized for performance with value type semantics.
/// </summary>
public struct Array2i : IEquatable<Array2i>
{
    public int X { get; set; }
    public int Y { get; set; }

    public Array2i(int x, int y)
    {
        X = x;
        Y = y;
    }

    public Array2i(Vector2 vector)
    {
        X = (int)vector.X;
        Y = (int)vector.Y;
    }

    /// <summary>
    /// Zero array (0, 0).
    /// </summary>
    public static Array2i Zero => new(0, 0);

    /// <summary>
    /// Creates from Vector2 by rounding.
    /// </summary>
    public static Array2i FromVector2(Vector2 vector)
    {
        return new Array2i((int)System.Math.Round(vector.X), (int)System.Math.Round(vector.Y));
    }

    /// <summary>
    /// Converts to Vector2.
    /// </summary>
    public readonly Vector2 ToVector2()
    {
        return new Vector2(X, Y);
    }

    /// <summary>
    /// Element-wise addition.
    /// </summary>
    public static Array2i operator +(Array2i left, Array2i right)
    {
        return new Array2i(left.X + right.X, left.Y + right.Y);
    }

    /// <summary>
    /// Element-wise subtraction.
    /// </summary>
    public static Array2i operator -(Array2i left, Array2i right)
    {
        return new Array2i(left.X - right.X, left.Y - right.Y);
    }

    /// <summary>
    /// Element-wise multiplication.
    /// </summary>
    public static Array2i operator *(Array2i left, int scalar)
    {
        return new Array2i(left.X * scalar, left.Y * scalar);
    }

    /// <summary>
    /// Element-wise division.
    /// </summary>
    public static Array2i operator /(Array2i left, int scalar)
    {
        return new Array2i(left.X / scalar, left.Y / scalar);
    }

    /// <summary>
    /// Element-wise comparison (all elements must be less than).
    /// </summary>
    public static bool operator <(Array2i left, Array2i right)
    {
        return left.X < right.X && left.Y < right.Y;
    }

    /// <summary>
    /// Element-wise comparison (all elements must be less than or equal).
    /// </summary>
    public static bool operator <=(Array2i left, Array2i right)
    {
        return left.X <= right.X && left.Y <= right.Y;
    }

    /// <summary>
    /// Element-wise comparison (all elements must be greater than).
    /// </summary>
    public static bool operator >(Array2i left, Array2i right)
    {
        return left.X > right.X && left.Y > right.Y;
    }

    /// <summary>
    /// Element-wise comparison (all elements must be greater than or equal).
    /// </summary>
    public static bool operator >=(Array2i left, Array2i right)
    {
        return left.X >= right.X && left.Y >= right.Y;
    }

    /// <summary>
    /// Equality comparison.
    /// </summary>
    public static bool operator ==(Array2i left, Array2i right)
    {
        return left.X == right.X && left.Y == right.Y;
    }

    /// <summary>
    /// Inequality comparison.
    /// </summary>
    public static bool operator !=(Array2i left, Array2i right)
    {
        return !(left == right);
    }

    public readonly bool Equals(Array2i other)
    {
        return X == other.X && Y == other.Y;
    }

    public override readonly bool Equals(object? obj)
    {
        return obj is Array2i other && Equals(other);
    }

    public override readonly int GetHashCode()
    {
        return HashCode.Combine(X, Y);
    }

    public override readonly string ToString()
    {
        return $"({X}, {Y})";
    }

    /// <summary>
    /// Deconstructs into x and y.
    /// </summary>
    public readonly void Deconstruct(out int x, out int y)
    {
        x = X;
        y = Y;
    }
}