#include <SDL2/SDL.h>
#include <GL/glew.h>
#include <SDL2/SDL_opengl.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>

#include <iostream>
#include <vector>
#include <cmath>
#include <cstring>
#include <unordered_map>
#include <memory>
#include <algorithm>
#include <climits>
#include <string>

// Build:
//   mkdir build && cd build && cmake .. && make -j$(nproc)
//   ./minicraft

// ─── Constants ───────────────────────────────────────────────────────────────
static const int   SCREEN_W    = 1280;
static const int   SCREEN_H    = 720;
static const int   CHUNK_SIZE  = 16;
static const int   WORLD_H     = 64;
static const int   RENDER_DIST = 6;
static const float MOVE_SPEED  = 6.0f;
static const float MOUSE_SENS  = 0.12f;
static const float GRAVITY     = -22.0f;
static const float JUMP_VEL    = 9.0f;
static const float HW          = 0.3f;
static const float PH          = 1.8f;
static const int   HOTBAR_SIZE = 8;

// ─── Block types ─────────────────────────────────────────────────────────────
enum BlockType : uint8_t { AIR=0, GRASS, DIRT, STONE, WOOD, LEAVES, SAND, SNOW, WATER };
static const int NUM_BLOCK_TYPES = 9;

struct BlockColor { float r,g,b; };
static const BlockColor BLOCK_COLORS[] = {
    {0,0,0},
    {0.40f,0.72f,0.24f}, // GRASS
    {0.55f,0.40f,0.22f}, // DIRT
    {0.50f,0.50f,0.50f}, // STONE
    {0.45f,0.30f,0.15f}, // WOOD
    {0.22f,0.55f,0.18f}, // LEAVES
    {0.88f,0.83f,0.52f}, // SAND
    {0.92f,0.95f,0.98f}, // SNOW
    {0.18f,0.42f,0.88f}, // WATER
};
static const char* BLOCK_NAMES[] = {
    "Air","Grass","Dirt","Stone","Wood","Leaves","Sand","Snow","Water"
};
static const float FACE_SHADE[] = {1.0f, 0.5f, 0.8f, 0.7f, 0.65f, 0.65f};

// ─── Perlin Noise ─────────────────────────────────────────────────────────────
static int P[512];
static void initNoise(int seed){
    int perm[256]; for(int i=0;i<256;i++) perm[i]=i;
    unsigned rng=(unsigned)seed;
    for(int i=255;i>0;i--){ rng=rng*1664525u+1013904223u; int j=(rng>>16)%(i+1); std::swap(perm[i],perm[j]); }
    for(int i=0;i<512;i++) P[i]=perm[i&255];
}
static float fade(float t){return t*t*t*(t*(t*6-15)+10);}
static float lerp(float a,float b,float t){return a+t*(b-a);}
static float grad(int h,float x,float y){h&=3;float u=(h<2)?x:y,v=(h<2)?y:x;return((h&1)?-u:u)+((h&2)?-v:v);}
static float noise2(float x,float y){
    int xi=(int)floorf(x)&255,yi=(int)floorf(y)&255;
    float xf=x-floorf(x),yf=y-floorf(y),u=fade(xf),v=fade(yf);
    int aa=P[P[xi]+yi],ab=P[P[xi]+yi+1],ba=P[P[xi+1]+yi],bb=P[P[xi+1]+yi+1];
    return lerp(lerp(grad(aa,xf,yf),grad(ba,xf-1,yf),u),lerp(grad(ab,xf,yf-1),grad(bb,xf-1,yf-1),u),v);
}
static float fbm(float x,float y,int oct=6){
    float val=0,amp=1,freq=1,max=0;
    for(int i=0;i<oct;i++){val+=noise2(x*freq,y*freq)*amp;max+=amp;amp*=0.5f;freq*=2.0f;}
    return val/max;
}

// ─── World chunk ─────────────────────────────────────────────────────────────
struct Chunk {
    int cx,cz;
    uint8_t blocks[CHUNK_SIZE][WORLD_H][CHUNK_SIZE];
    GLuint VAO=0,VBO=0,EBO=0;
    int indexCount=0;
    bool meshDirty=true,generated=false;
    Chunk(int cx,int cz):cx(cx),cz(cz){memset(blocks,AIR,sizeof(blocks));}
    ~Chunk(){if(VAO){glDeleteVertexArrays(1,&VAO);glDeleteBuffers(1,&VBO);glDeleteBuffers(1,&EBO);}}
};
struct ChunkKey{int x,z;bool operator==(const ChunkKey& o)const{return x==o.x&&z==o.z;}};
struct ChunkKeyHash{size_t operator()(const ChunkKey& k)const{return std::hash<long long>()((long long)k.x<<32|(unsigned)k.z);}};
using ChunkMap=std::unordered_map<ChunkKey,std::unique_ptr<Chunk>,ChunkKeyHash>;
static ChunkMap CHUNKS;

static void generateChunk(Chunk& c){
    int wx0=c.cx*CHUNK_SIZE,wz0=c.cz*CHUNK_SIZE;
    for(int x=0;x<CHUNK_SIZE;x++)
    for(int z=0;z<CHUNK_SIZE;z++){
        float wx=(wx0+x)*0.008f,wz=(wz0+z)*0.008f;
        float cont=fbm(wx*0.4f,wz*0.4f,4);
        float detail=fbm(wx*2.0f+5.3f,wz*2.0f+1.7f,5);
        float ridge=1.0f-fabsf(fbm(wx*0.8f+3.1f,wz*0.8f+8.9f,4));
        float h=12.0f+cont*18.0f+detail*6.0f+ridge*14.0f*std::max(0.0f,cont);
        int top=(int)h; top=std::max(2,std::min(WORLD_H-2,top));
        bool isSand=(top<16),isSnow=(top>38);
        for(int y=0;y<WORLD_H;y++){
            if(y==0)         c.blocks[x][y][z]=STONE;
            else if(y<top-4) c.blocks[x][y][z]=STONE;
            else if(y<top)   c.blocks[x][y][z]=isSand?SAND:DIRT;
            else if(y==top){ c.blocks[x][y][z]=isSand?SAND:(isSnow?SNOW:GRASS); }
            else if(y<=14)   c.blocks[x][y][z]=WATER;
            else             c.blocks[x][y][z]=AIR;
        }
        if(!isSand&&!isSnow&&top>=16&&top<36&&top+6<WORLD_H){
            unsigned col=(unsigned)((wx0+x)*73856093u^(unsigned)(wz0+z)*19349663u);
            if((col&0xFF)<18){
                int trunk=top+1;
                for(int t=trunk;t<trunk+4&&t<WORLD_H;t++) c.blocks[x][t][z]=WOOD;
                for(int dx=-2;dx<=2;dx++) for(int dz=-2;dz<=2;dz++) for(int dy=trunk+2;dy<=trunk+5;dy++){
                    int nx=x+dx,nz=z+dz;
                    if(nx>=0&&nx<CHUNK_SIZE&&nz>=0&&nz<CHUNK_SIZE&&dy<WORLD_H)
                        if(c.blocks[nx][dy][nz]==AIR) c.blocks[nx][dy][nz]=LEAVES;
                }
            }
        }
    }
    c.generated=true;
}

static uint8_t getBlock(int wx,int wy,int wz){
    if(wy<0) return STONE; if(wy>=WORLD_H) return AIR;
    int cx=(int)floorf((float)wx/CHUNK_SIZE),cz=(int)floorf((float)wz/CHUNK_SIZE);
    auto it=CHUNKS.find({cx,cz}); if(it==CHUNKS.end()) return STONE;
    return it->second->blocks[wx-cx*CHUNK_SIZE][wy][wz-cz*CHUNK_SIZE];
}
static void setBlock(int wx,int wy,int wz,uint8_t val){
    if(wy<0||wy>=WORLD_H) return;
    int cx=(int)floorf((float)wx/CHUNK_SIZE),cz=(int)floorf((float)wz/CHUNK_SIZE);
    auto it=CHUNKS.find({cx,cz}); if(it==CHUNKS.end()) return;
    int lx=wx-cx*CHUNK_SIZE,lz=wz-cz*CHUNK_SIZE;
    it->second->blocks[lx][wy][lz]=val; it->second->meshDirty=true;
    if(lx==0){auto n=CHUNKS.find({cx-1,cz});if(n!=CHUNKS.end())n->second->meshDirty=true;}
    if(lx==CHUNK_SIZE-1){auto n=CHUNKS.find({cx+1,cz});if(n!=CHUNKS.end())n->second->meshDirty=true;}
    if(lz==0){auto n=CHUNKS.find({cx,cz-1});if(n!=CHUNKS.end())n->second->meshDirty=true;}
    if(lz==CHUNK_SIZE-1){auto n=CHUNKS.find({cx,cz+1});if(n!=CHUNKS.end())n->second->meshDirty=true;}
}

// ─── World mesh ──────────────────────────────────────────────────────────────
struct Vertex{float x,y,z,r,g,b;};
static bool shouldDrawFace(uint8_t cur,int wx,int wy,int wz){
    uint8_t nb=getBlock(wx,wy,wz);
    if(nb==AIR) return true;
    if(nb==WATER||nb==LEAVES) return cur!=nb;
    return false;
}
static void addFace(std::vector<Vertex>& verts,std::vector<GLuint>& idx,
    glm::vec3 v0,glm::vec3 v1,glm::vec3 v2,glm::vec3 v3,float r,float g,float b,float shade){
    GLuint base=(GLuint)verts.size(); float sr=r*shade,sg=g*shade,sb=b*shade;
    verts.push_back({v0.x,v0.y,v0.z,sr,sg,sb}); verts.push_back({v1.x,v1.y,v1.z,sr,sg,sb});
    verts.push_back({v2.x,v2.y,v2.z,sr,sg,sb}); verts.push_back({v3.x,v3.y,v3.z,sr,sg,sb});
    idx.insert(idx.end(),{base,base+1,base+2,base,base+2,base+3});
}
static void buildChunkMesh(Chunk& c){
    std::vector<Vertex> verts; std::vector<GLuint> idx;
    int wx0=c.cx*CHUNK_SIZE,wz0=c.cz*CHUNK_SIZE;
    for(int x=0;x<CHUNK_SIZE;x++) for(int y=0;y<WORLD_H;y++) for(int z=0;z<CHUNK_SIZE;z++){
        uint8_t b=c.blocks[x][y][z]; if(b==AIR) continue;
        float r=BLOCK_COLORS[b].r,g=BLOCK_COLORS[b].g,bl=BLOCK_COLORS[b].b;
        float bx=wx0+x,by=y,bz=wz0+z; int wx=wx0+x,wz=wz0+z;
        if(shouldDrawFace(b,wx,y+1,wz)) addFace(verts,idx,{bx,by+1,bz+1},{bx+1,by+1,bz+1},{bx+1,by+1,bz},{bx,by+1,bz},r,g,bl,FACE_SHADE[0]);
        if(shouldDrawFace(b,wx,y-1,wz)) addFace(verts,idx,{bx,by,bz},{bx+1,by,bz},{bx+1,by,bz+1},{bx,by,bz+1},r,g,bl,FACE_SHADE[1]);
        if(shouldDrawFace(b,wx,y,wz+1)) addFace(verts,idx,{bx,by,bz+1},{bx+1,by,bz+1},{bx+1,by+1,bz+1},{bx,by+1,bz+1},r,g,bl,FACE_SHADE[2]);
        if(shouldDrawFace(b,wx,y,wz-1)) addFace(verts,idx,{bx+1,by,bz},{bx,by,bz},{bx,by+1,bz},{bx+1,by+1,bz},r,g,bl,FACE_SHADE[3]);
        if(shouldDrawFace(b,wx-1,y,wz)) addFace(verts,idx,{bx,by,bz},{bx,by,bz+1},{bx,by+1,bz+1},{bx,by+1,bz},r,g,bl,FACE_SHADE[4]);
        if(shouldDrawFace(b,wx+1,y,wz)) addFace(verts,idx,{bx+1,by,bz+1},{bx+1,by,bz},{bx+1,by+1,bz},{bx+1,by+1,bz+1},r,g,bl,FACE_SHADE[5]);
    }
    if(!c.VAO){glGenVertexArrays(1,&c.VAO);glGenBuffers(1,&c.VBO);glGenBuffers(1,&c.EBO);}
    glBindVertexArray(c.VAO);
    glBindBuffer(GL_ARRAY_BUFFER,c.VBO); glBufferData(GL_ARRAY_BUFFER,verts.size()*sizeof(Vertex),verts.data(),GL_DYNAMIC_DRAW);
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,c.EBO); glBufferData(GL_ELEMENT_ARRAY_BUFFER,idx.size()*sizeof(GLuint),idx.data(),GL_DYNAMIC_DRAW);
    glVertexAttribPointer(0,3,GL_FLOAT,GL_FALSE,sizeof(Vertex),(void*)0); glEnableVertexAttribArray(0);
    glVertexAttribPointer(1,3,GL_FLOAT,GL_FALSE,sizeof(Vertex),(void*)(3*sizeof(float))); glEnableVertexAttribArray(1);
    c.indexCount=(int)idx.size(); c.meshDirty=false;
}

// ─── Shaders ─────────────────────────────────────────────────────────────────
static const char* VS_SRC=R"(
#version 330 core
layout(location=0) in vec3 aPos;
layout(location=1) in vec3 aColor;
out vec3 vColor; out float vFog;
uniform mat4 uMVP; uniform vec3 uCamPos;
void main(){
    gl_Position=uMVP*vec4(aPos,1.0); vColor=aColor;
    float dist=length(aPos-uCamPos);
    vFog=clamp((dist-60.0)/40.0,0.0,1.0);
})";
static const char* FS_SRC=R"(
#version 330 core
in vec3 vColor; in float vFog; out vec4 fragColor;
void main(){
    vec3 fogColor=vec3(0.53,0.81,0.98);
    fragColor=vec4(mix(vColor,fogColor,vFog),1.0);
})";

static const char* VS_UI=R"(
#version 330 core
layout(location=0) in vec2 aPos;
layout(location=1) in vec3 aColor;
out vec3 vColor;
uniform mat4 uProj;
void main(){ gl_Position=uProj*vec4(aPos,0.0,1.0); vColor=aColor; })";
static const char* FS_UI=R"(
#version 330 core
in vec3 vColor; out vec4 fragColor;
uniform float uAlpha;
void main(){ fragColor=vec4(vColor,uAlpha); })";

static GLuint compileShader(GLenum type,const char* src){
    GLuint s=glCreateShader(type); glShaderSource(s,1,&src,nullptr); glCompileShader(s);
    GLint ok; glGetShaderiv(s,GL_COMPILE_STATUS,&ok);
    if(!ok){char buf[512];glGetShaderInfoLog(s,512,nullptr,buf);std::cerr<<"Shader err: "<<buf<<"\n";}
    return s;
}
static GLuint buildProg(const char* vs,const char* fs){
    GLuint v=compileShader(GL_VERTEX_SHADER,vs),f=compileShader(GL_FRAGMENT_SHADER,fs);
    GLuint p=glCreateProgram(); glAttachShader(p,v); glAttachShader(p,f); glLinkProgram(p);
    glDeleteShader(v); glDeleteShader(f); return p;
}

// ─── 2D UI Renderer ──────────────────────────────────────────────────────────
struct UIRenderer {
    GLuint prog=0,VAO=0,VBO=0;
    GLint projLoc=-1,alphaLoc=-1;
    glm::mat4 proj{1.0f};

    void init(){
        prog=buildProg(VS_UI,FS_UI);
        projLoc=glGetUniformLocation(prog,"uProj");
        alphaLoc=glGetUniformLocation(prog,"uAlpha");
        proj=glm::ortho(0.0f,(float)SCREEN_W,(float)SCREEN_H,0.0f);

        glGenVertexArrays(1,&VAO);
        glGenBuffers(1,&VBO);
        glBindVertexArray(VAO);
        glBindBuffer(GL_ARRAY_BUFFER,VBO);
        glBufferData(GL_ARRAY_BUFFER,1024*sizeof(float),nullptr,GL_DYNAMIC_DRAW);
        glVertexAttribPointer(0,2,GL_FLOAT,GL_FALSE,5*sizeof(float),(void*)0);
        glEnableVertexAttribArray(0);
        glVertexAttribPointer(1,3,GL_FLOAT,GL_FALSE,5*sizeof(float),(void*)(2*sizeof(float)));
        glEnableVertexAttribArray(1);
        glBindVertexArray(0);
    }

    void begin(){
        glDisable(GL_DEPTH_TEST);
        glDisable(GL_CULL_FACE);
        glEnable(GL_BLEND);
        glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
        glUseProgram(prog);
        glUniformMatrix4fv(projLoc,1,GL_FALSE,glm::value_ptr(proj));
        glBindVertexArray(VAO);
    }

    void end(){
        glDisable(GL_BLEND);
        glEnable(GL_DEPTH_TEST);
        glEnable(GL_CULL_FACE);
        glBindVertexArray(0);
    }

    void rect(float x,float y,float w,float h,float r,float g,float b,float a=1.0f){
        float verts[]={
            x,   y,   r,g,b,
            x+w, y,   r,g,b,
            x+w, y+h, r,g,b,
            x,   y,   r,g,b,
            x+w, y+h, r,g,b,
            x,   y+h, r,g,b
        };
        glUniform1f(alphaLoc,a);
        glBindBuffer(GL_ARRAY_BUFFER,VBO);
        glBufferSubData(GL_ARRAY_BUFFER,0,sizeof(verts),verts);
        glDrawArrays(GL_TRIANGLES,0,6);
    }

    void outline(float x,float y,float w,float h,float r,float g,float b,float t=2.0f){
        rect(x,y,w,t,r,g,b);
        rect(x,y+h-t,w,t,r,g,b);
        rect(x,y,t,h,r,g,b);
        rect(x+w-t,y,t,h,r,g,b);
    }
};

// ─── Global UI + PlayerModel forward declarations ────────────────────────────
// Declared here so drawText / drawHUD / drawInventory can use them.
static UIRenderer UI;

// ─── Tiny bitmap font (5×7 per glyph, ASCII 32–126) ─────────────────────────
static const uint8_t FONT5x7[][5] = {
    {0x00,0x00,0x00,0x00,0x00}, // space
    {0x00,0x00,0x5F,0x00,0x00}, // !
    {0x00,0x07,0x00,0x07,0x00}, // "
    {0x14,0x7F,0x14,0x7F,0x14}, // #
    {0x24,0x2A,0x7F,0x2A,0x12}, // $
    {0x23,0x13,0x08,0x64,0x62}, // %
    {0x36,0x49,0x55,0x22,0x50}, // &
    {0x00,0x05,0x03,0x00,0x00}, // '
    {0x00,0x1C,0x22,0x41,0x00}, // (
    {0x00,0x41,0x22,0x1C,0x00}, // )
    {0x14,0x08,0x3E,0x08,0x14}, // *
    {0x08,0x08,0x3E,0x08,0x08}, // +
    {0x00,0x50,0x30,0x00,0x00}, // ,
    {0x08,0x08,0x08,0x08,0x08}, // -
    {0x00,0x60,0x60,0x00,0x00}, // .
    {0x20,0x10,0x08,0x04,0x02}, // /
    {0x3E,0x51,0x49,0x45,0x3E}, // 0
    {0x00,0x42,0x7F,0x40,0x00}, // 1
    {0x42,0x61,0x51,0x49,0x46}, // 2
    {0x21,0x41,0x45,0x4B,0x31}, // 3
    {0x18,0x14,0x12,0x7F,0x10}, // 4
    {0x27,0x45,0x45,0x45,0x39}, // 5
    {0x3C,0x4A,0x49,0x49,0x30}, // 6
    {0x01,0x71,0x09,0x05,0x03}, // 7
    {0x36,0x49,0x49,0x49,0x36}, // 8
    {0x06,0x49,0x49,0x29,0x1E}, // 9
    {0x00,0x36,0x36,0x00,0x00}, // :
    {0x00,0x56,0x36,0x00,0x00}, // ;
    {0x08,0x14,0x22,0x41,0x00}, // <
    {0x14,0x14,0x14,0x14,0x14}, // =
    {0x00,0x41,0x22,0x14,0x08}, // >
    {0x02,0x01,0x51,0x09,0x06}, // ?
    {0x32,0x49,0x79,0x41,0x3E}, // @
    {0x7E,0x11,0x11,0x11,0x7E}, // A
    {0x7F,0x49,0x49,0x49,0x36}, // B
    {0x3E,0x41,0x41,0x41,0x22}, // C
    {0x7F,0x41,0x41,0x22,0x1C}, // D
    {0x7F,0x49,0x49,0x49,0x41}, // E
    {0x7F,0x09,0x09,0x09,0x01}, // F
    {0x3E,0x41,0x49,0x49,0x7A}, // G
    {0x7F,0x08,0x08,0x08,0x7F}, // H
    {0x00,0x41,0x7F,0x41,0x00}, // I
    {0x20,0x40,0x41,0x3F,0x01}, // J
    {0x7F,0x08,0x14,0x22,0x41}, // K
    {0x7F,0x40,0x40,0x40,0x40}, // L
    {0x7F,0x02,0x04,0x02,0x7F}, // M
    {0x7F,0x04,0x08,0x10,0x7F}, // N
    {0x3E,0x41,0x41,0x41,0x3E}, // O
    {0x7F,0x09,0x09,0x09,0x06}, // P
    {0x3E,0x41,0x51,0x21,0x5E}, // Q
    {0x7F,0x09,0x19,0x29,0x46}, // R
    {0x46,0x49,0x49,0x49,0x31}, // S
    {0x01,0x01,0x7F,0x01,0x01}, // T
    {0x3F,0x40,0x40,0x40,0x3F}, // U
    {0x1F,0x20,0x40,0x20,0x1F}, // V
    {0x3F,0x40,0x38,0x40,0x3F}, // W
    {0x63,0x14,0x08,0x14,0x63}, // X
    {0x07,0x08,0x70,0x08,0x07}, // Y
    {0x61,0x51,0x49,0x45,0x43}, // Z
    {0x00,0x7F,0x41,0x41,0x00}, // [
    {0x02,0x04,0x08,0x10,0x20}, // backslash
    {0x00,0x41,0x41,0x7F,0x00}, // ]
    {0x04,0x02,0x01,0x02,0x04}, // ^
    {0x40,0x40,0x40,0x40,0x40}, // _
    {0x00,0x01,0x02,0x04,0x00}, // `
    {0x20,0x54,0x54,0x54,0x78}, // a
    {0x7F,0x48,0x44,0x44,0x38}, // b
    {0x38,0x44,0x44,0x44,0x20}, // c
    {0x38,0x44,0x44,0x48,0x7F}, // d
    {0x38,0x54,0x54,0x54,0x18}, // e
    {0x08,0x7E,0x09,0x01,0x02}, // f
    {0x0C,0x52,0x52,0x52,0x3E}, // g
    {0x7F,0x08,0x04,0x04,0x78}, // h
    {0x00,0x44,0x7D,0x40,0x00}, // i
    {0x20,0x40,0x44,0x3D,0x00}, // j
    {0x7F,0x10,0x28,0x44,0x00}, // k
    {0x00,0x41,0x7F,0x40,0x00}, // l
    {0x7C,0x04,0x18,0x04,0x78}, // m
    {0x7C,0x08,0x04,0x04,0x78}, // n
    {0x38,0x44,0x44,0x44,0x38}, // o
    {0x7C,0x14,0x14,0x14,0x08}, // p
    {0x08,0x14,0x14,0x18,0x7C}, // q
    {0x7C,0x08,0x04,0x04,0x08}, // r
    {0x48,0x54,0x54,0x54,0x20}, // s
    {0x04,0x3F,0x44,0x40,0x20}, // t
    {0x3C,0x40,0x40,0x20,0x7C}, // u
    {0x1C,0x20,0x40,0x20,0x1C}, // v
    {0x3C,0x40,0x30,0x40,0x3C}, // w
    {0x44,0x28,0x10,0x28,0x44}, // x
    {0x0C,0x50,0x50,0x50,0x3C}, // y
    {0x44,0x64,0x54,0x4C,0x44}, // z
    {0x00,0x08,0x36,0x41,0x00}, // {
    {0x00,0x00,0x7F,0x00,0x00}, // |
    {0x00,0x41,0x36,0x08,0x00}, // }
    {0x10,0x08,0x08,0x10,0x08}, // ~
};

static void drawText(const char* text,float x,float y,float scale,
                     float r,float g,float b,float a=1.0f){
    float cx=x;
    for(int i=0;text[i];i++){
        int c=text[i]-32;
        if(c<0||c>=(int)(sizeof(FONT5x7)/sizeof(FONT5x7[0]))){cx+=(6*scale);continue;}
        for(int col=0;col<5;col++){
            uint8_t bits=FONT5x7[c][col];
            for(int row=0;row<7;row++){
                if(bits&(1<<row))
                    UI.rect(cx+col*scale,y+row*scale,scale,scale,r,g,b,a);
            }
        }
        cx+=6*scale;
    }
}

// ─── Inventory ───────────────────────────────────────────────────────────────
struct Inventory {
    uint8_t hotbar[HOTBAR_SIZE]={GRASS,DIRT,STONE,WOOD,LEAVES,SAND,SNOW,WATER};
    int selected=0;
    bool open=false;
    uint8_t selectedBlock()const{return hotbar[selected];}
};

static void drawInventory(Inventory& inv){
    const float SLOT=52.0f;
    const float GAP=6.0f;
    const float BORDER=4.0f;
    int n=HOTBAR_SIZE;
    float totalW=n*(SLOT+GAP)-GAP;
    float hx=(SCREEN_W-totalW)*0.5f;
    float hy=SCREEN_H-SLOT-16.0f;

    // Background bar
    UI.rect(hx-8,hy-8,totalW+16,SLOT+16,0.15f,0.15f,0.15f,0.75f);
    UI.outline(hx-8,hy-8,totalW+16,SLOT+16,0.0f,0.0f,0.0f);

    for(int i=0;i<n;i++){
        float sx=hx+i*(SLOT+GAP),sy=hy;
        bool sel=(i==inv.selected);
        UI.rect(sx,sy,SLOT,SLOT,sel?0.30f:0.20f,sel?0.30f:0.20f,sel?0.30f:0.20f,0.9f);
        uint8_t bt=inv.hotbar[i];
        if(bt!=AIR){
            auto& bc=BLOCK_COLORS[bt];
            UI.rect(sx+BORDER,sy+BORDER,SLOT-2*BORDER,SLOT-2*BORDER-10,bc.r,bc.g,bc.b,1.0f);
            UI.rect(sx+BORDER,sy+SLOT-BORDER-10-4,SLOT-2*BORDER,4,bc.r*0.65f,bc.g*0.65f,bc.b*0.65f,1.0f);
        }
        if(sel) UI.outline(sx,sy,SLOT,SLOT,1.0f,1.0f,1.0f,BORDER*0.5f);
        else    UI.outline(sx,sy,SLOT,SLOT,0.0f,0.0f,0.0f,2.0f);
        char num[3]; snprintf(num,3,"%d",i+1);
        drawText(num,sx+4,sy+SLOT-12,1.5f,0.8f,0.8f,0.8f);
    }

    {
        uint8_t bt=inv.selectedBlock();
        const char* name=BLOCK_NAMES[bt];
        float tw=strlen(name)*6*2.0f;
        drawText(name,(SCREEN_W-tw)*0.5f,hy-26,2.0f,1.0f,1.0f,1.0f,0.9f);
    }

    if(!inv.open) return;

    const int COLS=4;
    const int ROWS=(NUM_BLOCK_TYPES-1+COLS-1)/COLS;
    float iw=COLS*(SLOT+GAP)-GAP+32.0f;
    float ih=ROWS*(SLOT+GAP)-GAP+60.0f;
    float ix=(SCREEN_W-iw)*0.5f;
    float iy=(SCREEN_H-ih)*0.5f;

    UI.rect(0,0,(float)SCREEN_W,(float)SCREEN_H,0,0,0,0.45f);
    UI.rect(ix,iy,iw,ih,0.18f,0.18f,0.18f,0.95f);
    UI.outline(ix,iy,iw,ih,0.6f,0.6f,0.6f,2.0f);
    drawText("INVENTORY",ix+10,iy+10,2.0f,1.0f,1.0f,1.0f);

    for(int bi=1;bi<NUM_BLOCK_TYPES;bi++){
        int row=(bi-1)/COLS,col=(bi-1)%COLS;
        float sx=ix+16+col*(SLOT+GAP);
        float sy=iy+40+row*(SLOT+GAP);
        bool inHotbar=false;
        for(int h=0;h<HOTBAR_SIZE;h++) if(inv.hotbar[h]==bi) inHotbar=true;
        auto& bc=BLOCK_COLORS[bi];
        UI.rect(sx,sy,SLOT,SLOT,0.25f,0.25f,0.25f,0.9f);
        UI.rect(sx+BORDER,sy+BORDER,SLOT-2*BORDER,SLOT-2*BORDER-8,bc.r,bc.g,bc.b,1.0f);
        UI.rect(sx+BORDER,sy+SLOT-BORDER-8-4,SLOT-2*BORDER,4,bc.r*0.65f,bc.g*0.65f,bc.b*0.65f,1.0f);
        UI.outline(sx,sy,SLOT,SLOT,inHotbar?1.0f:0.4f,inHotbar?1.0f:0.4f,inHotbar?0.0f:0.4f,2.0f);
        float scale=1.5f;
        float tw=strlen(BLOCK_NAMES[bi])*6*scale;
        float tx=sx+(SLOT-tw)*0.5f;
        drawText(BLOCK_NAMES[bi],tx,sy+SLOT-10,scale,0.9f,0.9f,0.9f);
    }
    drawText("Click a slot (1-8) to select. E to close.",ix+10,iy+ih-18,1.5f,0.7f,0.7f,0.7f);
}

// ─── HUD ─────────────────────────────────────────────────────────────────────
static void drawHUD(const glm::vec3& pos,uint8_t /*selBlock*/,bool thirdPerson){
    float cx=(float)SCREEN_W/2,cy=(float)SCREEN_H/2;
    UI.rect(cx-1,cy-10,2,20,1,1,1,0.85f);
    UI.rect(cx-10,cy-1,20,2,1,1,1,0.85f);
    UI.rect(cx-1,cy-1,2,2,0,0,0,0.85f);

    char buf[64];
    snprintf(buf,64,"X:%.0f Y:%.0f Z:%.0f",pos.x,pos.y-PH,pos.z);
    UI.rect(6,6,strlen(buf)*6*1.5f+6,18,0,0,0,0.5f);
    drawText(buf,9,9,1.5f,1.0f,1.0f,1.0f);

    if(thirdPerson)
        drawText("F5: 3rd Person",9,28,1.5f,1.0f,1.0f,0.6f);
}

// ─── Camera / Player ─────────────────────────────────────────────────────────
struct Camera {
    glm::vec3 pos{0,40,0};
    float yaw=0,pitch=0;
    glm::vec3 vel{0,0,0};
    bool onGround=false;

    glm::vec3 forward()const{
        float y=glm::radians(yaw),p=glm::radians(pitch);
        return glm::normalize(glm::vec3(cosf(p)*cosf(y),sinf(p),cosf(p)*sinf(y)));
    }
    glm::vec3 right()const{return glm::normalize(glm::cross(forward(),{0,1,0}));}
    glm::mat4 firstPersonView()const{return glm::lookAt(pos,pos+forward(),{0,1,0});}
    glm::mat4 thirdPersonView()const{
        glm::vec3 fwd=forward();
        glm::vec3 eye=pos-fwd*6.0f+glm::vec3(0,2,0);
        return glm::lookAt(eye,pos,{0,1,0});
    }
};

static bool solidAt(float fx,float fy,float fz){
    int x=(int)floorf(fx),y=(int)floorf(fy),z=(int)floorf(fz);
    if(y<0) return true; if(y>=WORLD_H) return false;
    uint8_t b=getBlock(x,y,z); return b!=AIR&&b!=WATER&&b!=LEAVES;
}
static bool aabbSolid(float px,float py,float pz){
    int x0=(int)floorf(px-HW),x1=(int)floorf(px+HW);
    int y0=(int)floorf(py-PH),y1=(int)floorf(py+0.05f);
    int z0=(int)floorf(pz-HW),z1=(int)floorf(pz+HW);
    for(int x=x0;x<=x1;x++) for(int y=y0;y<=y1;y++) for(int z=z0;z<=z1;z++)
        if(solidAt((float)x,(float)y,(float)z)) return true;
    return false;
}
static void moveCamera(Camera& cam,const glm::vec3& move,float dt){
    cam.pos.x+=move.x*dt; if(aabbSolid(cam.pos.x,cam.pos.y,cam.pos.z)) cam.pos.x-=move.x*dt;
    cam.pos.z+=move.z*dt; if(aabbSolid(cam.pos.x,cam.pos.y,cam.pos.z)) cam.pos.z-=move.z*dt;
    cam.vel.y+=GRAVITY*dt; cam.pos.y+=cam.vel.y*dt;
    if(cam.vel.y<0){
        if(aabbSolid(cam.pos.x,cam.pos.y,cam.pos.z)){
            cam.pos.y=floorf(cam.pos.y-PH)+1.0f+PH+0.001f;
            cam.vel.y=0; cam.onGround=true;
        } else cam.onGround=false;
    } else {
        if(aabbSolid(cam.pos.x,cam.pos.y,cam.pos.z)){
            cam.pos.y=floorf(cam.pos.y+0.05f)-0.05f-0.001f; cam.vel.y=0;
        }
        cam.onGround=false;
    }
}

// ─── Player model (3rd person) ───────────────────────────────────────────────
struct PlayerModel {
    GLuint VAO=0,VBO=0,EBO=0;
    std::vector<Vertex> verts;
    std::vector<GLuint> idx;
    int indexCount=0;

    void addBox(float x0,float y0,float z0,float x1,float y1,float z1,
                float r,float g,float b){
        auto face=[&](glm::vec3 v0,glm::vec3 v1,glm::vec3 v2,glm::vec3 v3,float shade){
            GLuint base=(GLuint)verts.size();
            float sr=r*shade,sg=g*shade,sb=b*shade;
            verts.push_back({v0.x,v0.y,v0.z,sr,sg,sb}); verts.push_back({v1.x,v1.y,v1.z,sr,sg,sb});
            verts.push_back({v2.x,v2.y,v2.z,sr,sg,sb}); verts.push_back({v3.x,v3.y,v3.z,sr,sg,sb});
            idx.insert(idx.end(),{base,base+1,base+2,base,base+2,base+3});
        };
        face({x0,y1,z0},{x1,y1,z0},{x1,y1,z1},{x0,y1,z1},1.0f);   // Top
        face({x0,y0,z1},{x1,y0,z1},{x1,y0,z0},{x0,y0,z0},0.5f);   // Bottom
        face({x0,y0,z1},{x1,y0,z1},{x1,y1,z1},{x0,y1,z1},0.8f);   // Front
        face({x1,y0,z0},{x0,y0,z0},{x0,y1,z0},{x1,y1,z0},0.7f);   // Back
        face({x0,y0,z0},{x0,y0,z1},{x0,y1,z1},{x0,y1,z0},0.65f);  // Left
        face({x1,y0,z1},{x1,y0,z0},{x1,y1,z0},{x1,y1,z1},0.65f);  // Right
    }

    void build(){
        verts.clear(); idx.clear();
        float sk=0.90f,sg_=0.72f,sb_=0.55f;
        float tr=0.25f,tg=0.45f,tb=0.75f;
        float lr=0.20f,lg=0.20f,lb=0.60f;
        float hr=0.30f,hg=0.18f,hb=0.08f;

        addBox(-0.3f,1.55f,-0.3f, 0.3f,2.15f,0.3f, sk,sg_,sb_);   // Head
        addBox(-0.32f,1.9f,-0.32f, 0.32f,2.17f,0.32f, hr,hg,hb);  // Hair
        addBox(-0.3f,0.7f,-0.2f, 0.3f,1.5f,0.2f, tr,tg,tb);       // Body
        addBox(-0.55f,0.7f,-0.15f, -0.32f,1.45f,0.15f, sk,sg_,sb_);// Left arm
        addBox( 0.32f,0.7f,-0.15f,  0.55f,1.45f,0.15f, sk,sg_,sb_);// Right arm
        addBox(-0.28f,0.0f,-0.15f, -0.05f,0.7f,0.15f, lr,lg,lb);   // Left leg
        addBox( 0.05f,0.0f,-0.15f,  0.28f,0.7f,0.15f, lr,lg,lb);   // Right leg

        indexCount=(int)idx.size();

        if(!VAO){glGenVertexArrays(1,&VAO);glGenBuffers(1,&VBO);glGenBuffers(1,&EBO);}
        glBindVertexArray(VAO);
        glBindBuffer(GL_ARRAY_BUFFER,VBO);
        glBufferData(GL_ARRAY_BUFFER,verts.size()*sizeof(Vertex),verts.data(),GL_STATIC_DRAW);
        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,EBO);
        glBufferData(GL_ELEMENT_ARRAY_BUFFER,idx.size()*sizeof(GLuint),idx.data(),GL_STATIC_DRAW);
        glVertexAttribPointer(0,3,GL_FLOAT,GL_FALSE,sizeof(Vertex),(void*)0); glEnableVertexAttribArray(0);
        glVertexAttribPointer(1,3,GL_FLOAT,GL_FALSE,sizeof(Vertex),(void*)(3*sizeof(float))); glEnableVertexAttribArray(1);
        glBindVertexArray(0);
    }

    void draw(GLuint prog,GLint mvpLoc,GLint camLoc,
              const glm::mat4& proj,const glm::mat4& view,
              const Camera& cam) const {
        glm::vec3 feet=cam.pos-glm::vec3(0,PH,0);
        glm::mat4 model=glm::translate(glm::mat4(1),feet);
        model=glm::rotate(model,glm::radians(cam.yaw+180.0f),glm::vec3(0,1,0));
        glm::mat4 mvp=proj*view*model;
        glUseProgram(prog);
        glUniformMatrix4fv(mvpLoc,1,GL_FALSE,glm::value_ptr(mvp));
        glUniform3fv(camLoc,1,glm::value_ptr(cam.pos));
        glBindVertexArray(VAO);
        glDrawElements(GL_TRIANGLES,(GLsizei)indexCount,GL_UNSIGNED_INT,0);
        glBindVertexArray(0);
    }
};

static PlayerModel PLAYER_MODEL;

// ─── Raycast ─────────────────────────────────────────────────────────────────
static bool raycast(const Camera& cam,glm::ivec3& hit,glm::ivec3& prev){
    glm::vec3 dir=cam.forward(),p=cam.pos;
    glm::ivec3 last{(int)floorf(p.x),(int)floorf(p.y),(int)floorf(p.z)};
    for(float t=0;t<8.0f;t+=0.05f){
        glm::vec3 rp=p+dir*t;
        glm::ivec3 bp{(int)floorf(rp.x),(int)floorf(rp.y),(int)floorf(rp.z)};
        if(bp.y<0||bp.y>=WORLD_H){last=bp;continue;}
        uint8_t b=getBlock(bp.x,bp.y,bp.z);
        if(b!=AIR&&b!=WATER){hit=bp;prev=last;return true;}
        last=bp;
    }
    return false;
}

// ─── Chunk streaming ─────────────────────────────────────────────────────────
static void updateChunks(int pcx,int pcz){
    for(int dx=-RENDER_DIST;dx<=RENDER_DIST;dx++)
    for(int dz=-RENDER_DIST;dz<=RENDER_DIST;dz++){
        ChunkKey k{pcx+dx,pcz+dz};
        if(CHUNKS.find(k)==CHUNKS.end()){
            auto c=std::make_unique<Chunk>(k.x,k.z); generateChunk(*c);
            CHUNKS[k]=std::move(c);
            for(auto& [nk,nc]:CHUNKS) if(abs(nk.x-k.x)+abs(nk.z-k.z)==1) nc->meshDirty=true;
        }
    }
    std::vector<ChunkKey> toRemove;
    for(auto& [k,c]:CHUNKS) if(abs(k.x-pcx)>RENDER_DIST+1||abs(k.z-pcz)>RENDER_DIST+1) toRemove.push_back(k);
    for(auto& k:toRemove) CHUNKS.erase(k);
}

// ─── Main ────────────────────────────────────────────────────────────────────
int main(){
    SDL_Init(SDL_INIT_VIDEO);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION,3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION,3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK,SDL_GL_CONTEXT_PROFILE_CORE);
    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER,1);
    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE,24);

    SDL_Window* win=SDL_CreateWindow("MiniCraft",
        SDL_WINDOWPOS_CENTERED,SDL_WINDOWPOS_CENTERED,SCREEN_W,SCREEN_H,
        SDL_WINDOW_OPENGL|SDL_WINDOW_SHOWN);
    SDL_GLContext ctx=SDL_GL_CreateContext(win);
    SDL_GL_SetSwapInterval(1);
    glewExperimental=GL_TRUE; glewInit();

    glEnable(GL_DEPTH_TEST); glEnable(GL_CULL_FACE); glCullFace(GL_BACK);
    glClearColor(0.53f,0.81f,0.98f,1.0f);

    GLuint prog3d=buildProg(VS_SRC,FS_SRC);
    GLint mvpLoc=glGetUniformLocation(prog3d,"uMVP");
    GLint camLoc=glGetUniformLocation(prog3d,"uCamPos");

    UI.init();
    initNoise(12345);

    std::cout<<"Generating world...\n";
    updateChunks(0,0);
    for(auto& [k,c]:CHUNKS) if(c->generated) buildChunkMesh(*c);

    Camera cam;
    for(int y=WORLD_H-1;y>=0;y--){
        uint8_t b=getBlock(0,y,0);
        if(b!=AIR&&b!=WATER){cam.pos.y=(float)y+1+PH+0.1f;break;}
    }
    cam.pos.x=0.5f; cam.pos.z=0.5f;

    PLAYER_MODEL.build();

    glm::mat4 proj=glm::perspective(glm::radians(70.0f),(float)SCREEN_W/SCREEN_H,0.05f,500.0f);
    SDL_SetRelativeMouseMode(SDL_TRUE);

    Inventory inv;
    bool thirdPerson=false;
    bool running=true;
    Uint64 last=SDL_GetPerformanceCounter();
    int lastPcx=INT_MAX,lastPcz=INT_MAX;

    std::cout<<"=== MiniCraft ===\n"
             <<"WASD        Move\n"
             <<"Space       Jump\n"
             <<"Mouse       Look\n"
             <<"LMB         Break block\n"
             <<"RMB         Place block\n"
             <<"1-8         Hotbar slot\n"
             <<"E           Open/close inventory\n"
             <<"F5          Toggle 3rd person\n"
             <<"ESC         Quit\n";

    while(running){
        Uint64 now=SDL_GetPerformanceCounter();
        float dt=(float)(now-last)/SDL_GetPerformanceFrequency();
        if(dt>0.1f) dt=0.1f;
        last=now;

        SDL_Event e;
        while(SDL_PollEvent(&e)){
            if(e.type==SDL_QUIT) running=false;
            if(e.type==SDL_KEYDOWN){
                switch(e.key.keysym.sym){
                    case SDLK_ESCAPE: running=false; break;
                    case SDLK_e:
                        inv.open=!inv.open;
                        SDL_SetRelativeMouseMode(inv.open?SDL_FALSE:SDL_TRUE);
                        break;
                    case SDLK_F5: thirdPerson=!thirdPerson; break;
                    case SDLK_1: inv.selected=0; break;
                    case SDLK_2: inv.selected=1; break;
                    case SDLK_3: inv.selected=2; break;
                    case SDLK_4: inv.selected=3; break;
                    case SDLK_5: inv.selected=4; break;
                    case SDLK_6: inv.selected=5; break;
                    case SDLK_7: inv.selected=6; break;
                    case SDLK_8: inv.selected=7; break;
                }
            }
            if(e.type==SDL_MOUSEWHEEL){
                inv.selected=(inv.selected-e.wheel.y+HOTBAR_SIZE)%HOTBAR_SIZE;
            }
            if(!inv.open){
                if(e.type==SDL_MOUSEMOTION){
                    cam.yaw+=e.motion.xrel*MOUSE_SENS;
                    cam.pitch-=e.motion.yrel*MOUSE_SENS;
                    if(cam.pitch>89)cam.pitch=89; if(cam.pitch<-89)cam.pitch=-89;
                }
                if(e.type==SDL_MOUSEBUTTONDOWN){
                    glm::ivec3 hit,prev;
                    if(raycast(cam,hit,prev)){
                        if(e.button.button==SDL_BUTTON_LEFT)
                            setBlock(hit.x,hit.y,hit.z,AIR);
                        else if(e.button.button==SDL_BUTTON_RIGHT)
                            setBlock(prev.x,prev.y,prev.z,inv.selectedBlock());
                    }
                }
            } else {
                if(e.type==SDL_MOUSEBUTTONDOWN&&e.button.button==SDL_BUTTON_LEFT){
                    const int COLS=4; const float SLOT=52.0f,GAP=6.0f;
                    float iw=COLS*(SLOT+GAP)-GAP+32.0f;
                    float ih=((NUM_BLOCK_TYPES-1+COLS-1)/COLS)*(SLOT+GAP)-GAP+60.0f;
                    float ix=(SCREEN_W-iw)*0.5f,iy=(SCREEN_H-ih)*0.5f;
                    int mx=e.button.x,my=e.button.y;
                    for(int bi=1;bi<NUM_BLOCK_TYPES;bi++){
                        int row=(bi-1)/COLS,col=(bi-1)%COLS;
                        float sx=ix+16+col*(SLOT+GAP),sy=iy+40+row*(SLOT+GAP);
                        if(mx>=sx&&mx<=sx+SLOT&&my>=sy&&my<=sy+SLOT){
                            inv.hotbar[inv.selected]=(uint8_t)bi;
                        }
                    }
                }
            }
        }

        if(!inv.open){
            const Uint8* keys=SDL_GetKeyboardState(nullptr);
            glm::vec3 fwd=cam.forward(); fwd.y=0; if(glm::length(fwd)>0) fwd=glm::normalize(fwd);
            glm::vec3 rgt=cam.right();   rgt.y=0; if(glm::length(rgt)>0) rgt=glm::normalize(rgt);
            glm::vec3 move{0,0,0};
            if(keys[SDL_SCANCODE_W]) move+=fwd*MOVE_SPEED;
            if(keys[SDL_SCANCODE_S]) move-=fwd*MOVE_SPEED;
            if(keys[SDL_SCANCODE_D]) move+=rgt*MOVE_SPEED;
            if(keys[SDL_SCANCODE_A]) move-=rgt*MOVE_SPEED;
            if(keys[SDL_SCANCODE_SPACE]&&cam.onGround) cam.vel.y=JUMP_VEL;
            moveCamera(cam,move,dt);
        }

        int pcx=(int)floorf(cam.pos.x/CHUNK_SIZE);
        int pcz=(int)floorf(cam.pos.z/CHUNK_SIZE);
        if(pcx!=lastPcx||pcz!=lastPcz){ updateChunks(pcx,pcz); lastPcx=pcx; lastPcz=pcz; }
        int rebuilt=0;
        for(auto& [k,c]:CHUNKS)
            if(c->meshDirty&&c->generated){buildChunkMesh(*c);if(++rebuilt>=4)break;}

        // ── Render 3D world ──
        glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
        glm::mat4 view=thirdPerson?cam.thirdPersonView():cam.firstPersonView();
        glm::mat4 mvp=proj*view;

        glUseProgram(prog3d);
        glUniformMatrix4fv(mvpLoc,1,GL_FALSE,glm::value_ptr(mvp));
        glUniform3fv(camLoc,1,glm::value_ptr(cam.pos));
        for(auto& [k,c]:CHUNKS)
            if(c->indexCount>0){glBindVertexArray(c->VAO);glDrawElements(GL_TRIANGLES,c->indexCount,GL_UNSIGNED_INT,0);}

        // ── Player model (3rd person only) ──
        if(thirdPerson)
            PLAYER_MODEL.draw(prog3d,mvpLoc,camLoc,proj,view,cam);

        // ── 2D UI ──
        UI.begin();
        drawHUD(cam.pos,inv.selectedBlock(),thirdPerson);
        drawInventory(inv);
        UI.end();

        SDL_GL_SwapWindow(win);
    }

    CHUNKS.clear();
    glDeleteProgram(prog3d);
    glDeleteProgram(UI.prog);
    glDeleteVertexArrays(1,&UI.VAO); glDeleteBuffers(1,&UI.VBO);
    glDeleteVertexArrays(1,&PLAYER_MODEL.VAO);
    glDeleteBuffers(1,&PLAYER_MODEL.VBO); glDeleteBuffers(1,&PLAYER_MODEL.EBO);
    SDL_GL_DeleteContext(ctx);
    SDL_DestroyWindow(win);
    SDL_Quit();
    return 0;
}