#include "state.h"

techneck_s       tc_game_state_g;

#include <glad/glad.h>
#include <SDL2/SDL.h>
#include <linmath.h>

mat4x4                  projection_matrix;
mat4x4                  view_matrix;

float triangle_vertices[108] = {
    // Front
    -0.5f, -0.5f, -0.5f,
    -0.5f, 0.5f, -0.5f,
    0.5f, -0.5f, -0.5f,
    
    0.5f, 0.5f, -0.5f,
    0.5f, -0.5f, -0.5f,
    -0.5f, 0.5f, -0.5f,
    
    // Back
    -0.5f, -0.5f, 0.5f,
    -0.5f, 0.5f, 0.5f,
    0.5f, -0.5f, 0.5f,
    
    0.5f, 0.5f, 0.5f,
    0.5f, -0.5f, 0.5f,
    -0.5f, 0.5f, 0.5f,
    
    // Left
    -0.5f, 0.5f, -0.5f,
    -0.5f, -0.5f, -0.5f,
    -0.5f, -0.5f, 0.5f,
    
    -0.5f, -0.5f, -0.5f,
    -0.5f, 0.5f, 0.5f,
    -0.5f, -0.5f, 0.5f,
    
    // Right
    0.5f, 0.5f, -0.5f,
    0.5f, -0.5f, -0.5f,
    0.5f, -0.5f, 0.5f,
    
    0.5f, -0.5f, -0.5f,
    0.5f, 0.5f, 0.5f,
    0.5f, -0.5f, 0.5f,
    
    // Top
    -0.5f, 0.5f, -0.5f,
    -0.5f, 0.5f, 0.5f,
    0.5f, 0.5f, -0.5f,
    
    0.5f, 0.5f, 0.5f,
    -0.5f, 0.5f, 0.5f,
    0.5f, 0.5f, -0.5f,
    
    // Bottom
    -0.5f, -0.5f, -0.5f,
    -0.5f, -0.5f, 0.5f,
    0.5f, -0.5f, -0.5f,
    
    0.5f, -0.5f, 0.5f,
    -0.5f, -0.5f, 0.5f,
    0.5f, -0.5f, -0.5f,
    
    
};

tc_vec3_s               tc_camera_position = { 0.0f, 0.0f, 0.0f };
tc_vec3_s               tc_camera_rotation = { 0.0f, 0.0f, 0.0f };

tc_block_s block;

void render_block(tc_block_s block)
{
    mat4x4              model_matrix;
    mat4x4_translate(model_matrix, block.position.x, block.position.y, block.position.z);
    // mat4x4_rotate_X(view_matrix, model_matrix, block.rotation.x);
    // mat4x4_rotate_Y(view_matrix, model_matrix, block.rotation.y);
    // mat4x4_rotate_Z(view_matrix, model_matrix, block.rotation.z);
    
    int model_matrix_uniform_location = glGetUniformLocation(tc_game_state_g.renderer.draw_shader.program_id, "model_matrix");
    glUniformMatrix4fv(model_matrix_uniform_location, 1, GL_FALSE, &model_matrix[0][0]);
    
    glBindBuffer(GL_ARRAY_BUFFER, block.drawing.vbo);
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void *) 0);
    glEnableVertexAttribArray(0);
    glDrawArrays(GL_TRIANGLES, 0, 36);
}

tc_block_s tc_new_block_at_3f(float x, float y, float z)
{
    tc_block_s          block;
    block.position.x            = x;
    block.position.y            = y;
    block.position.z            = z;
    glGenBuffers(1, &block.drawing.vbo);
    glBindBuffer(GL_ARRAY_BUFFER, block.drawing.vbo);
    glBufferData(GL_ARRAY_BUFFER, sizeof(float) * 108, &triangle_vertices[0], GL_STATIC_DRAW);
    
    return block;
}

void render()
{
    float           color[4] = { 0.0f, 1.0f, 0.0f, 1.0f };
    glClearBufferfv(GL_COLOR, 0, color);
    float depth = 10000000.0f;
    glClearBufferfv(GL_DEPTH, 0, &depth);
    
    mat4x4_perspective(projection_matrix, 120, 1200 / 800, 0.0001f, 1000.0f);
    mat4x4_translate(view_matrix, -tc_camera_position.x, -tc_camera_position.y, tc_camera_position.z);
    // mat4x4_rotate_X(view_matrix, view_matrix, tc_camera_rotation.x);
    // mat4x4_rotate_Y(view_matrix, view_matrix, tc_camera_rotation.y);
    // mat4x4_rotate_Z(view_matrix, view_matrix, tc_camera_rotation.z);
    
    glUseProgram(tc_game_state_g.renderer.draw_shader.program_id);
    
    int projection_uniform_location = glGetUniformLocation(tc_game_state_g.renderer.draw_shader.program_id, "projection_matrix");
    glUniformMatrix4fv(projection_uniform_location, 1, GL_FALSE, &projection_matrix[0][0]);
    
    int view_uniform_location       = glGetUniformLocation(tc_game_state_g.renderer.draw_shader.program_id, "view_matrix");
    glUniformMatrix4fv(view_uniform_location, 1, GL_FALSE, &view_matrix[0][0]);
    // printf("%d\n", view_uniform_location);
    
    render_block(block);
    
    SDL_GL_SwapWindow(tc_game_state_g.renderer.window);
}

bool                    shift_pressed       = false;
bool                    go_up               = false;
bool                    go_left             = false;
bool                    go_right            = false;
bool                    go_forward          = false;
bool                    go_backwards        = false;

bool update()
{

    SDL_Event               event;
    while(SDL_PollEvent(&event))
    {
        switch(event.type)
        {
            case SDL_QUIT:
                SDL_HideWindow(tc_game_state_g.renderer.window);
                return false;
            break;
            
            case SDL_WINDOWEVENT:
            {
                if(event.window.event == SDL_WINDOWEVENT_RESIZED)
                {
                    puts("RESIZED");
                }
            } break;
            case SDL_KEYDOWN:
                
                if(event.key.keysym.scancode == SDL_SCANCODE_W)
                {
                    go_forward = true;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_S)
                {
                    go_backwards = true;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_A)
                {
                    go_left = true;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_D)
                {
                    go_right = true;;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_SPACE)
                {
                    go_up = true;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_LSHIFT)
                {
                    shift_pressed = true;
                }
                
            break;
            
            case SDL_KEYUP:
                
                if(event.key.keysym.scancode == SDL_SCANCODE_W)
                {
                    go_forward = false;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_S)
                {
                    go_backwards = false;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_A)
                {
                    go_left = false;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_D)
                {
                    go_right = false;;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_SPACE)
                {
                    go_up = false;
                }
                
                if(event.key.keysym.scancode == SDL_SCANCODE_LSHIFT)
                {
                    shift_pressed = false;
                }
                
            break;
        }
    }
    
    if(shift_pressed)
    {
        tc_camera_position.y -= 0.25;
    }
    
    if(go_up)
    {
        tc_camera_position.y += 0.25;
    }
    
    if(go_left)
    {
        tc_camera_position.x -= 0.25;
    }
    
    if(go_right)
    {
        tc_camera_position.x += 0.25;
    }
    
    if(go_forward)
    {
        tc_camera_position.z += 0.25;
    }
    
    if(go_backwards)
    {
        tc_camera_position.z -= 0.25;
    }
    return true;
}

void flushput(const char *message)
{
    puts(message);
    fflush(stdout);
}

int main(int argc, char **argv)
{
    tc_game_state_g         = tc_init();
    
    block    = tc_new_block_at_3f(0.0, 0.0, 0.0);
    
    int64_t                 frame_index         = 1;
    while(frame_index > 0)
    {
        if(!update())
        {
                frame_index = -1;
        }
        render();
        
        if(frame_index == 1)
        {
            SDL_ShowWindow(tc_game_state_g.renderer.window);
        }
        
        block.position.x += 0.005f;
        
        ++frame_index;
        SDL_Delay(1000/60);
    }
    
    tc_cleanup();
    SDL_Quit();
    
    return 0;
}