/*******************************************************************************************
*
*   raylib [textures] example - raw data
*
*   Example complexity rating: [★★★☆] 3/4
*
*   NOTE: Images are loaded in CPU memory (RAM); textures are loaded in GPU memory (VRAM)
*
*   Example originally created with raylib 1.3, last time updated with raylib 3.5
*
*   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) 2015-2025 Ramon Santamaria (@raysan5)
*
********************************************************************************************/

using static Raylib_cs.Raylib;

namespace Examples.Textures;

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

    public string Name => "Textures / Raw Data";

    public string Title => "raylib [textures] example - raw data";

    private Texture2D fudesumi;
    private Texture2D checkedTex;

    public unsafe void Init()
    {
        // NOTE: Textures MUST be loaded after Window initialization (OpenGL context is required)

        // Load RAW image data (512x512, 32bit RGBA, no file header)
        var fudesumiRaw = LoadImageRaw(
            "resources/fudesumi.raw",
            384,
            512,
            PixelFormat.UncompressedR8G8B8A8,
            0
        );
        fudesumi = LoadTextureFromImage(fudesumiRaw);   // Upload CPU (RAM) image to GPU (VRAM)
        UnloadImage(fudesumiRaw);                       // Unload CPU (RAM) image data

        // Generate a checked texture by code
        var imWidth = 960;
        var imHeight = 480;

        // Dynamic memory allocation to store pixels data (Color type)
        // WARNING: Using raylib provided MemAlloc() that uses default raylib
        // internal memory allocator, so this data can be freed using UnloadImage()
        // that also uses raylib internal memory de-allocator
        var pixels = (Color*)Raylib.MemAlloc((uint)(imWidth * imHeight * sizeof(Color)));

        for (var y = 0; y < imHeight; y++)
        {
            for (var x = 0; x < imWidth; x++)
            {
                if (((x / 32 + y / 32) / 1) % 2 == 0)
                {
                    pixels[y * imWidth + x] = Color.Orange;
                }
                else
                {
                    pixels[y * imWidth + x] = Color.Gold;
                }
            }
        }

        // Load pixels data into an image structure and create texture
        // NOTE: We can assign pixels directly to data because Color is R8G8B8A8
        // data structure defining that pixelformat, format must be set properly
        var checkedIm = new Image
        {
            Data = pixels,
            Width = imWidth,
            Height = imHeight,
            Format = PixelFormat.UncompressedR8G8B8A8,
            Mipmaps = 1,
        };

        checkedTex = LoadTextureFromImage(checkedIm);
        Raylib.MemFree(pixels);         // Unload CPU (RAM) image data (pixels)
    }

    public void Update()
    {
        // Draw
        //----------------------------------------------------------------------------------
        BeginDrawing();
        ClearBackground(Color.RayWhite);

        var x = screenWidth / 2 - checkedTex.Width / 2;
        var y = screenHeight / 2 - checkedTex.Height / 2;
        DrawTexture(checkedTex, x, y, Fade(Color.White, 0.5f));
        DrawTexture(fudesumi, 430, -30, Color.White);

        DrawText("CHECKED TEXTURE ", 84, 85, 30, Color.Brown);
        DrawText("GENERATED by CODE", 72, 148, 30, Color.Brown);
        DrawText("and RAW IMAGE LOADING", 46, 210, 30, Color.Brown);

        DrawText("(c) Fudesumi sprite by Eiden Marsal", 310, screenHeight - 20, 10, Color.Brown);

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

    public void Unload()
    {
        UnloadTexture(fudesumi);    // Texture unloading
        UnloadTexture(checkedTex);  // Texture unloading
    }

    public static int Main()
    {
        // Initialization
        //--------------------------------------------------------------------------------------
        InitWindow(screenWidth, screenHeight, "raylib [textures] example - raw data");

        SetTargetFPS(60);               // Set our game to run at 60 frames-per-second
        //---------------------------------------------------------------------------------------

        var game = new RawData();
        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;
    }
}