using VoxelEngine.World;
using VoxelEngine.World.Blocks;
using Xunit;

namespace VoxelEngine.Tests;

public class BlockRegistryTests
{
    [Fact]
    public void Get_ReturnsRegisteredBlockById()
    {
        var registry = new BlockRegistry();

        Assert.IsType<AirBlock>(registry.Get(0));
        Assert.IsType<StoneBlock>(registry.Get(1));
        Assert.IsType<DirtBlock>(registry.Get(2));
        Assert.IsType<GrassBlock>(registry.Get(3));
    }

    [Fact]
    public void Air_IsNotOpaqueOrSolid_OthersAre()
    {
        var registry = new BlockRegistry();

        Assert.False(registry.Get(0).IsOpaque);
        Assert.False(registry.Get(0).IsSolid);
        Assert.True(registry.Get(1).IsOpaque);
        Assert.True(registry.Get(1).IsSolid);
    }

    [Fact]
    public void Grass_HasDifferentTexturesPerFace()
    {
        var registry = new BlockRegistry();
        IBlock grass = registry.Get(3);

        Assert.Equal(new TileCoord(0, 1), grass.GetTextureTile(BlockFace.Top));
        Assert.Equal(new TileCoord(0, 0), grass.GetTextureTile(BlockFace.Bottom));
        Assert.Equal(new TileCoord(1, 1), grass.GetTextureTile(BlockFace.North));
    }

    [Fact]
    public void NamedAccessors_MatchIds()
    {
        var registry = new BlockRegistry();

        Assert.Equal((ushort)0, registry.Air.Id);
        Assert.Equal((ushort)1, registry.Stone.Id);
        Assert.Equal((ushort)2, registry.Dirt.Id);
        Assert.Equal((ushort)3, registry.Grass.Id);
    }

    [Fact]
    public void SandAndSnow_AreOpaque_WaterIsOpaque()
    {
        var registry = new BlockRegistry();
        Assert.True(registry.Get(4).IsOpaque);  // Sand
        Assert.True(registry.Get(5).IsOpaque);  // Snow
        Assert.True(registry.Get(6).IsOpaque);  // Water (single-pass renderer => opaque)
    }

    [Fact]
    public void Registry_ResolvesAllSevenBlocks()
    {
        var registry = new BlockRegistry();
        Assert.Equal("Air", registry.Get(0).Name);
        Assert.Equal("Stone", registry.Get(1).Name);
        Assert.Equal("Dirt", registry.Get(2).Name);
        Assert.Equal("Grass", registry.Get(3).Name);
        Assert.Equal("Sand", registry.Get(4).Name);
        Assert.Equal("Snow Block", registry.Get(5).Name);
        Assert.Equal("Water", registry.Get(6).Name);
    }

    [Fact]
    public void Registry_ResolvesOreBlocks_ByStableIds()
    {
        var registry = new BlockRegistry();

        Assert.Equal("Coal Ore",    registry.Get(7).Name);
        Assert.Equal("Iron Ore",    registry.Get(8).Name);
        Assert.Equal("Gold Ore",    registry.Get(9).Name);
        Assert.Equal("Diamond Ore", registry.Get(10).Name);
    }

    [Fact]
    public void Ores_AreOpaqueAndSolid()
    {
        var registry = new BlockRegistry();
        foreach (ushort id in new ushort[] { 7, 8, 9, 10 })
        {
            Assert.True(registry.Get(id).IsOpaque, $"ore id {id} should be opaque");
            Assert.True(registry.Get(id).IsSolid,  $"ore id {id} should be solid");
        }
    }

    [Fact]
    public void NamedOreAccessors_MatchIds()
    {
        var registry = new BlockRegistry();
        Assert.Equal((ushort)7,  registry.CoalOre.Id);
        Assert.Equal((ushort)8,  registry.IronOre.Id);
        Assert.Equal((ushort)9,  registry.GoldOre.Id);
        Assert.Equal((ushort)10, registry.DiamondOre.Id);
    }
}