/*******************************************************************************************
*
*   raylib [core] example - input virtual controls
*
*   Example complexity rating: [★★☆☆] 2/4
*
*   Example originally created with raylib 5.0, last time updated with raylib 5.0
*
*   Example contributed by GreenSnakeLinux (@GreenSnakeLinux),
*   reviewed by Ramon Santamaria (@raysan5), oblerion (@oblerion) and danilwhale (@danilwhale)
*
*   Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
*   BSD-like license that allows static linking with closed source software
*
*   Copyright (c) 2024-2025 GreenSnakeLinux (@GreenSnakeLinux) and Ramon Santamaria (@raysan5)
*
********************************************************************************************/

using System;
using System.Numerics;
using static Raylib_cs.Raylib;

namespace Examples.Core;

public enum PadButton
{
    BUTTON_NONE = -1,
    BUTTON_UP,
    BUTTON_LEFT,
    BUTTON_RIGHT,
    BUTTON_DOWN,
    BUTTON_MAX
}

public partial class InputVirtualControls : IExample
{
    private const int screenWidth = 800;
    private const int screenHeight = 450;

    public string Name => "Core / Input Virtual Controls";

    public string Title => "raylib [core] example - input virtual controls";

    private Vector2 padPosition;
    private float buttonRadius;
    private Vector2[] buttonPositions;
    private Vector2[][] arrowTris;
    private Color[] buttonLabelColors;
    private int pressedButton;
    private Vector2 inputPosition;
    private Vector2 playerPosition;
    private float playerSpeed;

    public void Init()
    {
        padPosition = new Vector2(100, 350);
        buttonRadius = 30;

        buttonPositions =
        [
            new Vector2(
                padPosition.X,padPosition.Y - buttonRadius * 1.5f
            ), // Up
            new Vector2(
                padPosition.X - buttonRadius * 1.5f, padPosition.Y
            ), // Left
            new Vector2(
                padPosition.X + buttonRadius * 1.5f, padPosition.Y
            ), // Right
            new Vector2(
                padPosition.X, padPosition.Y + buttonRadius * 1.5f
            ) // Down
        ];

        arrowTris = [
            // Up
            [
                new Vector2(
                    buttonPositions[0].X, buttonPositions[0].Y - 12
                ),
                new Vector2(
                    buttonPositions[0].X - 9, buttonPositions[0].Y + 9
                ),
                new Vector2(
                    buttonPositions[0].X + 9, buttonPositions[0].Y + 9
                )
            ],
            // Left
            [
                new Vector2(
                    buttonPositions[1].X + 9, buttonPositions[1].Y - 9
                ),
                new Vector2(
                    buttonPositions[1].X - 12, buttonPositions[1].Y
                ),
                new Vector2(
                    buttonPositions[1].X + 9, buttonPositions[1].Y + 9
                )
            ],
            // Right
            [
                new Vector2(
                    buttonPositions[2].X + 12, buttonPositions[2].Y
                ),
                new Vector2(
                    buttonPositions[2].X - 9, buttonPositions[2].Y - 9
                ),
                new Vector2(
                    buttonPositions[2].X - 9, buttonPositions[2].Y + 9
                )
            ],
            // Down
            [
                new Vector2(
                    buttonPositions[3].X - 9, buttonPositions[3].Y - 9
                ),
                new Vector2(
                    buttonPositions[3].X, buttonPositions[3].Y + 12
                ),
                new Vector2(
                    buttonPositions[3].X + 9, buttonPositions[3].Y - 9
                )
            ]
        ]
        ;

        buttonLabelColors = [
            Color.Yellow, // Up
            Color.Blue, // Left
            Color.Red, // Right
            Color.Green // Down
        ];

        pressedButton = (int)PadButton.BUTTON_NONE;
        inputPosition = new Vector2(0, 0);

        playerPosition = new Vector2((float)screenWidth / 2, (float)screenHeight / 2);
        playerSpeed = 75f;
    }

    public void Update()
    {
        // Update
        //--------------------------------------------------------------------------
        if ((GetTouchPointCount() > 0))
        {
            inputPosition = GetTouchPosition(0); // Use touch position
        }
        else
        {
            inputPosition = GetMousePosition(); // Use mouse position
        }

        // Reset pressed button to none
        pressedButton = (int)PadButton.BUTTON_NONE;

        // Make sure user is pressing left mouse button if they're from desktop
        if ((GetTouchPointCount() > 0) ||
            ((GetTouchPointCount() == 0) && IsMouseButtonDown(MouseButton.Left)))
        {
            // Find nearest D-Pad button to the input position
            for (var i = 0; i < (int)PadButton.BUTTON_MAX; i++)
            {
                var distX = MathF.Abs(buttonPositions[i].X - inputPosition.X);
                var distY = MathF.Abs(buttonPositions[i].Y - inputPosition.Y);

                if ((distX + distY < buttonRadius))
                {
                    pressedButton = i;
                    break;
                }
            }
        }

        // Move player according to pressed button
        switch ((PadButton)pressedButton)
        {
            case PadButton.BUTTON_UP:
                playerPosition.Y -= playerSpeed * GetFrameTime();
                break;
            case PadButton.BUTTON_LEFT:
                playerPosition.X -= playerSpeed * GetFrameTime();
                break;
            case PadButton.BUTTON_RIGHT:
                playerPosition.X += playerSpeed * GetFrameTime();
                break;
            case PadButton.BUTTON_DOWN:
                playerPosition.Y += playerSpeed * GetFrameTime();
                break;
            default:
                break;
        }
        //--------------------------------------------------------------------------

        // Draw
        //--------------------------------------------------------------------------
        BeginDrawing();

        ClearBackground(Color.RayWhite);

        // Draw world
        DrawCircleV(playerPosition, 50, Color.Maroon);

        // Draw GUI
        for (var i = 0; i < (int)PadButton.BUTTON_MAX; i++)
        {
            DrawCircleV(buttonPositions[i], buttonRadius, (i == pressedButton) ? Color.DarkGray : Color.Black);

            DrawTriangle(
                arrowTris[i][0],
                arrowTris[i][1],
                arrowTris[i][2],
                buttonLabelColors[i]
            );
        }

        DrawText("move the player with D-Pad buttons", 10, 10, 20, Color.DarkGray);

        EndDrawing();
        //--------------------------------------------------------------------------
    }

    public void Unload()
    {
    }

    public static int Main()
    {
        // Initialization
        //--------------------------------------------------------------------------------------
        InitWindow(screenWidth, screenHeight, "raylib [core] example - input virtual controls");

        SetTargetFPS(60);
        //--------------------------------------------------------------------------------------

        var game = new InputVirtualControls();
        game.Init();

        // Main game loop
        while (!WindowShouldClose()) // Detect window close button or ESC key
        {
            game.Update();
        }

        game.Unload();

        // De-Initialization
        //--------------------------------------------------------------------------------------
        CloseWindow(); // Close window and OpenGL context
        //--------------------------------------------------------------------------------------

        return 0;
    }
}